888 resultados para Sex-related growth
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The present study was designed to elucidate sex-related differences in two basic auditory and one basic visual aspect of sensory functioning, namely sensory discrimination of pitch, loudness, and brightness. Although these three aspects of sensory functioning are of vital importance in everyday life, little is known about whether men and women differ from each other in these sensory functions. Participants were 100 male and 100 female volunteers ranging in age from 18 to 30 years. Since sensory sensitivity may be positively related to individual levels of intelligence and musical experience, measures of psychometric intelligence and musical background were also obtained. Reliably better performance for men compared to women was found for pitch and loudness, but not for brightness discrimination. Furthermore, performance on loudness discrimination was positively related to psychometric intelligence, while pitch discrimination was positively related to both psychometric intelligence and levels of musical training. Additional regression analyses revealed that each of three predictor variables (sex, psychometric intelligence, and musical training) accounted for a statistically significant portion of unique variance in pitch discrimination. With regard to loudness discrimination, regression analysis yielded a statistically significant portion of unique variance for sex as a predictor variable, whereas psychometric intelligence just failed to reach statistical significance. The potential influence of sex hormones on sex-related differences in sensory functions is discussed.
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BACKGROUND Access to care may be implicated in disparities between men and women in death after acute coronary syndrome, especially among younger adults. We aimed to assess sex-related differences in access to care among patients with premature acute coronary syndrome and to identify clinical and gender-related determinants of access to care. METHODS We studied 1123 patients (18-55 yr) admitted to hospital for acute coronary syndrome and enrolled in the GENESIS-PRAXY cohort study. Outcome measures were door-to-electrocardiography, door-to-needle and door-to-balloon times, as well as proportions of patients undergoing cardiac catheterization, reperfusion or nonprimary percutaneous coronary intervention. We performed univariable and multivariable logistic regression analyses to identify clinical and gender-related determinants of timely procedures and use of invasive procedures. RESULTS Women were less likely than men to receive care within benchmark times for electrocardiography (≤ 10 min: 29% v. 38%, p = 0.02) or fibrinolysis (≤ 30 min: 32% v. 57%, p = 0.01). Women with ST-segment elevation myocardial infarction (MI) were less likely than men to undergo reperfusion therapy (primary percutaneous coronary intervention or fibrinolysis) (83% v. 91%, p = 0.01), and women with non-ST-segment elevation MI or unstable angina were less likely to undergo nonprimary percutaneous coronary intervention (48% v. 66%, p < 0.001). Clinical determinants of poorer access to care included anxiety, increased number of risk factors and absence of chest pain. Gender-related determinants included feminine traits of personality and responsibility for housework. INTERPRETATION Among younger adults with acute coronary syndrome, women and men had different access to care. Moreover, fewer than half of men and women with ST-segment elevation MI received timely primary coronary intervention. Our results also highlight that men and women with no chest pain and those with anxiety, several traditional risk factors and feminine personality traits were at particularly increased risk of poorer access to care.
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This study described the relationship of sexual maturation and blood pressure in a sample (n = 361) of white females, ages seven through 18, attending public schools in a defined area of Central Texas during October through December, 1984. Other correlates of blood pressure were also described for this sample.^ A survey was performed to obtain the data on height, weight, body mass, pulse rate, upper arm circumference and length, and blood pressure. Each subject self-assessed her secondary sex characteristics (breast and pubic hair) according to drawings of the Tanner stages of maturation. The subjects were interviewed to obtain data on personal health habits and menstrual status. Student age, ethnic group and place of residence were abstracted from school records. Parents or guardians of the subjects responded to a questionnaire pertaining to parental and subject health history and parents' occupation and educational attainment.^ In the simple linear regression analysis, sexual maturation and variables of body size were significantly (p < 0.001) and positively associated with systolic and fourth- and fifth-phase diastolic blood pressure. The demographic and socioeconomic variables were not sufficiently variant in this population to have differential effects on the relation between blood pressure and maturation. Stepwise multiple regression was used to assess the contribution of sexual maturation to the variance of blood pressure after accounting for the variables of body size. Sexual maturation (breast stage) along with weight, height and body mass remained in the multiple regression models for fourth- and fifth-phase diastolic blood pressure. Only height and body mass remained in the regression model for systolic blood pressure; sexual maturation did not contribute more to the explanation of the systolic blood pressure variance.^ The association of sexual maturation with blood pressure level was established in this sample of young white females. More research is needed first, to determine if this relationship prevails in other populations of young females, and second, to determine the relationship of sexual maturation sequence and change with the change of blood pressure during childhood and adolescence. ^
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Biological speciation ultimately results in prezygotic isolation—the inability of incipient species to mate with one another–but little is understood about the selection pressures and genetic changes that generate this outcome. The genus Chlamydomonas comprises numerous species of unicellular green algae, including numerous geographic isolates of the species C. reinhardtii. This diverse collection has allowed us to analyze the evolution of two sex-related genes: the mid gene of C. reinhardtii, which determines whether a gamete is mating-type plus or minus, and the fus1 gene, which dictates a cell surface glycoprotein utilized by C. reinhardtii plus gametes to recognize minus gametes. Low stringency Southern analyses failed to detect any fus1 homologs in other Chlamydomonas species and detected only one mid homolog, documenting that both genes have diverged extensively during the evolution of the lineage. The one mid homolog was found in C. incerta, the species in culture that is most closely related to C. reinhardtii. Its mid gene carries numerous nonsynonymous and synonymous codon changes compared with the C. reinhardtii mid gene. In contrast, very high sequence conservation of both the mid and fus1 sequences is found in natural isolates of C. reinhardtii, indicating that the genes are not free to drift within a species but do diverge dramatically between species. Striking divergence of sex determination and mate recognition genes also has been encountered in a number of other eukaryotic phyla, suggesting that unique, and as yet unidentified, selection pressures act on these classes of genes during the speciation process.
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Early neurogenesis progresses by an initial massive proliferation of neuroepithelial cells followed by a sequential differentiation of the various mature neural cell types. The regulation of these processes by growth factors is poorly understood. We intend to understand, in a well-defined biological system, the embryonic chicken retina, the role of the insulin-related growth factors in neurogenesis. We demonstrate the local presence of signaling elements together with a biological response to the factors. Neuroretina at days 6-8 of embryonic development (E6-E8) expressed proinsulin/insulin and insulin-like growth factor I (IGF-I) mRNAs as well as insulin receptor and IGF type I receptor mRNAs. In parallel with this in vivo gene expression, E5 cultured neuroretinas synthesized and released to the medium a metabolically radiolabeled immunoprecipitable insulin-related peptide. Furthermore, insulin-related immunoreactive material with a HPLC mobility close to that of proinsulin was found in the E6-E8 vitreous humor. Exogenous chicken IGF-I, human insulin, and human proinsulin added to E6 cultured neuroretinas showed relatively close potencies stimulating proliferation, as determined by [methyl-3H]thymidine incorporation, with a plateau reached at 10(-8) M. These factors also stimulated neuronal differentiation, indicated by the expression of the neuron-specific antigen G4. Thus, insulin-related growth factors, interestingly including proinsulin, are present in the developing chicken retina and appear to play an autocrine/paracrine stimulatory role in the progression of neurogenesis.
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Background: Although many studies have investigated sexual communication between parents and children in Kenya, none have focused singularly on grandparent and grandchild communication when grandparents are primary caregivers. Further, few studies have asked about specific topics related to sex, instead asking generally about “sex related topics” or focusing on HIV/AIDS. This research aims to investigate communication on ten specific sex- related topics between grandparents who are primary caregivers and their grandchildren. The primary research aim was to identify facilitators and barriers to grandparent-grandchild communication associated with frequency of communication. A secondary exploratory question was whether frequency of communication and youth satisfaction with communication were associated with youth’s desire for more communication in the future. Methods: The study was conducted in urban and peri-urban central Kenya. A convenience sample of 193 grandparents and 166 twelve to fifteen year old grandchildren were identified by community health workers. A cross sectional survey assessed nine potential barriers or facilitators to communication (e.g., frequency of communication, perceived grandparent knowledge, grandparent sense of responsibility to communication on a given topic) on ten specified sex- related topics (e.g., peer pressure on sex topics, romantic relationships, condoms). Bivariate and multivariable analyses identified significant associations between communication variables and the outcomes of interest. Results: Bivariate regression showed that higher grandchild age, grandchild gender, higher perceived grandparent knowledge, higher perceived grandparent comfort, higher grandparent-reported sense of responsibility, higher grandparent-reported belief that child should be aware of a given topic before initiating in sex, and higher youth’s own comfort during communication, were significantly associated with higher levels of communication frequency. In the multivariable model, higher grandchild age, gender, higher comfort during communication, and higher perceived grandparent knowledge remained significantly associated with higher levels communication frequency. For the secondary research question, higher communication frequency and higher levels of youth satisfaction were both significantly associated with higher levels of youth desire for more communication in bivariate regression, and higher levels of youth’s satisfaction with communication remained significantly associated with higher levels of youth’s desire for more in the adjusted analysis. Conclusions: This study found that several potential barriers and facilitators of communication are associated with both frequency of and youth’s desire for more communication. The association between grandchild age, gender and perceived grandparent knowledge and frequency of communication is similar to findings from other studies that have examined sex-related communication between parent primary caregivers and children. This finding has important implications for understanding grandparent and grandchild communication, and communication on specific topics in a population from Kenya. The positive association between youth satisfaction of and desire for more communication has important education policy and intervention implications, suggesting that if youth are satisfied with the communication with their caregivers, they may want to learn more.
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Sociedad Española de Cardiología. Proyecto de Registro Clínico de la Sección de Cardiología Clínica 2013
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The number of elderly people is growing in western populations, but only few maximal performance data exist for people >75 years, in particular for European octogenarians. This study was performed to characterize maximal performance of 55 independently living subjects (32 women, 81.1 +/- 3.4 years; 23 men, 81.7 +/- 2.9 years) with a focus on sex differences. Maximal performance was determined in a ramp test to exhaustion on a bicycle ergometer with ergospirometry, electrocardiogram and blood lactate measurements. Maximal isometric extension strength of the legs (MEL) was measured on a force platform in a seated position. Body composition was quantified by X-ray absorptiometry. In >25% of the subjects, serious cardiac abnormalities were detected during the ramp test with men more frequently being affected than women. Maximal oxygen consumption and power output were 18.2 +/- 3.2 versus 25.9 +/- 5.9 ml min(-1) kg(-1) and 66 +/- 12 versus 138 +/- 40 W for women versus men, with a significant sex difference for both parameters. Men outperformed women for MEL with 19.0 +/- 3.8 versus 13.6 +/- 3.3 N kg(-1). Concomitantly, we found a higher proportion of whole body fat in women (32.1 +/- 6.2%) compared to men (20.5 +/- 4.4%). Our study extends previously available maximal performance data for endurance and strength to independently living European octogenarians. As all sex-related differences were still apparent after normalization to lean body mass, it is concluded that it is essential to differentiate between female and male subjects when considering maximal performance parameters in the oldest segment of our population.
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Over the last few decades, there has been a marked increase in media and debate surrounding a specific group of offences in modern Democratic nations which bear the brunt of the label ‘crimes against morality’. Included within this group are offences related to prostitution and pornography, homosexuality and incest and child sexual abuse. This book examines the nexus between sex, crime and morality from a theoretical perspective. This is the first academic text to offer an examination and analysis of the philosophical underpinnings of sex-related crimes and social attitudes towards them and the historical, anthropological and moral reasons for differentiating these crimes in contemporary western culture. The book is divided into three sections corresponding to three theoretical frameworks: Part 1 examines the moral temporality of sex and taboo as a foundation for legislation governing sex crimes Part 2 focuses on the geography of sex and deviance, specifically notions of public morality and the public private divide Part 3 examines the moral economy of sex and harm, including the social construction of harm. Sex, Crime and Morality will be key reading for students of criminology, criminal justice, gender studies and ethics, and will also be of interest to justice professionals.
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Over the last few decades, there has been a marked increase in media and debate surrounding a specific group of offences in modern Democratic nations which bear the brunt of the label ‘crimes against morality’. Included within this group are offences related to prostitution and pornography, homosexuality and incest and child sexual abuse. This book examines the nexus between sex, crime and morality from a theoretical perspective. This is the first academic text to offer an examination and analysis of the philosophical underpinnings of sex-related crimes and social attitudes towards them and the historical, anthropological and moral reasons for differentiating these crimes in contemporary western culture. The book is divided into three sections corresponding to three theoretical frameworks: - Part 1 examines the moral temporality of sex and taboo as a foundation for legislation governing sex crimes - Part 2 focuses on the geography of sex and deviance, specifically notions of public morality and the public private divide - Part 3 examines the moral economy of sex and harm, including the social construction of harm. Sex, Crime and Morality will be key reading for students of criminology, criminal justice, gender studies and ethics, and will also be of interest to justice professionals.
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In the ovary, two new members of the large TGF-beta superfamily of growth factors were discovered in the 1990s. The oocyte was shown to express two closely related growth factors that were named growth differentiation factor 9 (GDF-9) and growth differentiation factor 9B (GDF-9B). Both of these proteins are required for normal ovarian follicle development although their individual significance varies between species. GDF-9 and GDF-9B mRNAs are expressed in the human oocytes from the primary follicle stage onwards. This thesis project was aimed to define the signalling mechanisms utilized by the oocyte secreted GDF-9. We used primary cultures of human granulosa luteal cells (hGL) as our cell model, and recombinant adenovirus-mediated gene transfer in manipulating the TGF-b family signalling cascade molecules in these cells. Overexpression of the constitutively active forms of the seven type I receptors, the activin receptor-like kinases 1-7 (ALK1-7), using recombinant adenoviruses caused a specific activation of either the Smad1 or Smad2 pathway proteins depending on the ALK used. Activation of both Smad1 and Smad2 proteins also stimulated the expression of dimeric inhibin B protein in hGL cells. Treatment with recombinant GDF-9 protein induced the specific activation of the Smad2 pathway and stimulated the expression of inhibin betaB subunit mRNA as well as inhibin B protein secretion in our cell model. Recombinant GDF-9 also activated the Smad3-responsive CAGA-luciferase reported construct, and the GDF-9 response in hGL cells was markedly potentiated upon the overexpression of Alk5 by adenoviral gene transduction. Alk5 overexpression also enhanced the GDF-9 induced inhibin B secretion by these cells. Similarly, in a mouse teratocarcinoma cell line P19, GDF-9 could activate the Smad2/3 pathway, and overexpression of ALK5 in COS7 cells rendered them responsive to GDF-9. Furthermore, transfection of rat granulosa cells with small interfering RNA for ALK5 or overexpression of the inhibitory Smad7 resulted in dose-dependent suppression of GDF-9 effects. In conclusion, this thesis shows that both Smad1 and Smad2 pathways are involved in controlling the regulation of inhibin B secretion. Therefore, in addition to endocrine control of inhibin production by the pituitary gonadotropins, also local paracrine factors within in the ovary, like the oocyte-derived growth factors, may contribute to controlling inhibin secretion. This thesis shows as well that like other TGF-beta family ligands, also GDF-9 signalling is mediated by the canonical type I and type II receptors with serine/threonine kinase activity, and the intracellular transcription factors, the Smads. Although GDF-9 binds to the BMP type II receptor, its downstream actions are specifically mediated by the type I receptor, ALK5, and the Smad2 and Smad3 proteins.
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The paper deals with sex-wise growth rate of different body parts in relation to total length in Rita paviinentata (Gunther). Growth rates calculated on pooled data by using the common regression coefficient 'b' reveals isometric and homogeneous nature in sexes.
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随着全球气候变暖和温室效应加剧,干旱和荒漠化成为威胁人类生存和发展的主要 灾害,许多被子植物对干旱胁迫的生理、生态和生化响应已逐步得以报道,但很少有开 展干旱胁迫对雌雄异株植物的影响方面的研究。由于这类植物在长期进化过程中已经在 生长、性比、生殖格局、空间分布、资源配置和生物量分配等方面形成了明显的性别差 异,因此,干旱胁迫必将对其雌雄植株产生不同的生理生态影响。本研究以青杨为模式 植物,采用植物生态、生理及生物化学等研究方法,系统研究青杨雌雄植株在常温、增 温以及喷施外源脱落酸的条件下对干旱胁迫的响应,揭示其在生长形态、生物量分配、 光合作用、用水效率和生理生化等方面的性别间差异。主要研究结果如下: 1. 青杨雌雄植株对干旱胁迫的综合响应。 与较好水分条件相比,干旱胁迫显著降低了青杨雌雄植株的光合作用和生长发育, 影响了许多生理生化过程,并导致雌雄植株在生长发育、气体交换、用水效率、膜脂抗 氧化和抗氧化系统酶活性方面表现出显著的性别间差异。在较好水分条件下,雌雄植株 之间在株高、基径、生物量、净光合速率、蒸腾速率、用水效率以及丙二醛、脱落酸和 游离脯氨酸等生化物质含量方面均无显著差异。但在干旱胁迫下,雄株在生长发育、气 体交换、水分利用效率、膜脂过氧化保护和抗氧化系统酶活性方面均显著高于雌株,表 现出比雌株更高的株高、基径、叶面积、总叶片数、总生物量、总色素含量、类胡萝卜 素含量、净光合速率、蒸腾速率、羧化效率、光系统II最大光化学效率、内在水分利用 效率、碳同位素组分、过氧化氢酶和过氧化物酶活性等,而在CO2补偿点、比叶面积、 叶绿素a/b、丙二醛、脱落酸和超氧化物歧化酶活性等指标上显著低于雌株。与雌株相比, 雄株表现出更高的干旱胁迫适应能力,而雌株的生长发育和生理生化过程更易遭受干旱 胁迫的影响。 2. 干旱胁迫下的青杨雌雄植株对增温处理的综合响应 与环境温度相比,增温在干旱胁迫前后均显著促进了雌雄植株的生长发育、气体交 换,降低水分利用效率,影响生化物质含量,并促使青杨雌雄植株之间在干旱胁迫下表 现出显著的差异。在较好水分条件下,增温导致雌株的株高、基径、叶面积、总叶片数、 总生物量和超氧化物歧化酶活性显著高于雄株,而用水效率、丙二醛、脱落酸和游离脯 氨酸、抗坏血酸过氧化物酶和过氧化物酶活性低于雄株。在干旱胁迫下,增温将导致雄 株的株高、基径、叶面积、总生物量、净光合速率、蒸腾速率、气孔导度、总色素含量、 相对含水量、过氧化氢酶和抗坏血酸过氧化物酶活性等显著高于雌株,而光系统II 最大 光化学效率、内在水分利用效率、碳同位素组分、丙二醛、脱落酸、游离脯氨酸和超氧 化物歧化酶活性显著低于雌株。与雄株相比,水分较好条件下的增温有利于促进雌株的 生长发育,并在生理生态特征上优于雄株。而干旱胁迫下的增温则加剧了水分胁迫强度, 致使雌株的生长发育遭受比雄株更多的负面影响。 3. 干旱胁迫下的青杨雌雄植株对喷施外源脱落酸处理的综合响应 与对照相比,在干旱胁迫下喷施外源脱落酸可显著增加青杨雌雄植株的生长发育、 气体交换、降低水分利用效率,影响了生化物质含量,并导致青杨雌雄植株之间在干旱 胁迫下表现出显著的生理生态差异。在干旱胁迫下,喷施外源脱落酸致使雌株的株高、 叶面积、叶干重、细根干重、总生物量、净光合速率、蒸腾速率、气孔导度、光系统II 最大光化学效率、非光化学淬灭系数、相对含水量、总光合色素、类胡萝卜素、脱落酸、 超氧化物歧化酶和过氧化物酶活性的增加量显著高于雄株,而根重比、根冠比、细根/ 总根、比叶面积、内在水分利用效率、碳同位素组分、丙二醛、脯氨酸、过氧化氢酶和 抗坏血酸过氧化物酶活性等指标的减少量上显著低于雄株。与对照相比,干旱胁迫下的 喷施外源脱落酸则一定程度能减缓植株遭受胁迫的压力,促进植株生长和气体交换,减 少了植株体内的过剩自由基数量,并促使雌株的生长发育和光合能力显著提高,增强其 抗干旱胁迫能力。 With development of global warming and greenhouse effect, drought and desertification have been became main natural disasteres in resent years. Studies on ecophysiological responses of most angiosperm species to environmental stress have been reported, but little is known about dioecious plant responses to drought stress. Since significant differences on growth, survival, reproductive patterns, spatial distribution, as well as resource allocation between males and females of dioecious plant have been formed during evolutionary process, sexual different ecophysiological responses should be caused by drought stress. In this experiment, Populus cathayana Rehd. was used as model plant to study the sex-related responses to drought by using the ecological, physiological and biochemical methods under normal atmospheric temperature, elevated temperatures and exogenous abscisic acid (ABA) application treatment respectively, and to expose the sexual differences in growth, biomass allocation, photosynthesis, water use efficiency and some biochemical material contents in the males and females of dioecious plant. The results are follows: 1. A large set of parallel responses of males and females of P. cathayana to drought stress Compared with well-watered treatment, drought significantly decreased growth and photosynthesis of P. cathayana individuals, affected some physiological and biochemical processes, and induced males and females to exhibit obvious sexual differences in growth, gas exchange, water use efficiency, lipid peroxidation protection and antioxidant defenses enzyme system. Under well-watered treatment, there were no significant sexual differences in height growth (HG), basal diameter (BD), dry matter accumulation (DMA), net photosynthesis rate (A), transpiration (E), water use efficiency (WUE), and malondialdehyde (MDA), abscisic acid (ABA) and praline (Pro). However, under drought stress, males were found to exhibit higher HG, BD, leaf area (LA), total leaf number (TLA), DMA, total chlorophyll contents (TC), carotenoids content (Caro), A, E, carboxylation efficiency (CE), the maximum efficiency of PSII (Fv/Fm), intrinsic water use efficiency (WUE ), carbon isotope composition (δ13C), catalase (CAT), peroxidase (POD) and lower CO2 compensation point (Γ), specific leaf area (SLA), chlorophyll a/b ratio (Chla/Chlb), MDA, ABA and superoxide dismutase (SOD) than females. The results suggest that males possess greater drought resistance than do females and females suffer more negative effect on growth and development, physiological and biochemical processes than males under drought stress. 2. A large set of parallel responses of drought-stressed males and females of P. cathayana to elevated temperatures Compared with environmental temperature, elevated temperature treatment significant increased growth and gas exchange, decreased water use efficiency, changed some biochemical material contents of P. cathayana individuals, and induced males and females to exhibit obvious differences under drought stress. Under good water condition, elevated temperature treatment caused females to show significant higher HG, BD, LA, TLN, DMA, SOD activity, and great lower WUE, MDA, ABA, Pro, ascorbate peroxidase (APX) and POD than do males. On contrary, under drought condition, elevated temperature treatment induced males to exhibit higher HG, BD, LA, DMA, A, E, stomatal conductance (gs), relative water content (RWC), CAT, APX activity but lower Fv/Fm, WUE, δ13C, MDA, ABA, Pro, SOD activity than do females. The results suggest that females will benefit from elevating temperature under good water condition by possessing better ecophysiological processes than that of males, but will suffer from greater negative effects than do males when grown under drought stress with elevated temperature treatment. 3. A large set of parallel responses of drought-stressed males and females of P. cathayana to exogenous ABA application Compared with controls, exogenous ABA application under drought greatly increased growth and gas exchange, decreased water use efficiency, changed some biochemical material contents in P. cathayana individuals, and induced males and females to exhibit obvious sexual differences under drought. Under drought stress, exogenous ABA application induced females to exhibit more increases in HG, LA, leaf weight (LW), fine root weight (FRW), DMA, A, E, g, Fv/Fm, non-photochemical quenching coefficient (qN), RWC, TC, Caro, ABA, SOD, POD s activity than males, but to show lower decreases in root/weight ratio (RWR), root mass/foliage area ratio (RF), fine root/total root ratio (FT), SLA, WUE, δ13C, MDA, Pro, CAT, APX than males. The results suggest that exogenous ABA application under drought stress will eliminate negative damages caused by drought stress at a certain extent,promote the growth and gas exchange of plant and decrease the number of superfluous 1O2 in plant cells of males and females of P. cathayana. Furthermore, exogenous ABA application promoted more drought resistance in females than in males by increasing more growth and photosynthetic capacity in females under drought stress.