Seed germination and seedling morphology of the seagrass, Halophila engelmannii (Hydrocharitaceae)

Seeds of Halophila engelmannii Aschers., that were collected in Redfish Bay, Texas, at weekly intervals from mid-May to mid-June 1986, began to germinate 3–4 weeks after collection. Most of the collections subsequently showed an increase in the rate of germination under increased light intensity and all had a stoppage of germination after transfer to darkness, indicating a light requirement to break endogenous seed dormancy. During the 5 weeks after seeds germinated, seedlings in soil culture produced a rosette of six leaves before the appearance of a rhizome bud in the axil of the third leaf. The first node of the rhizome produced a root and an upright shoot with a pseudowhorl of three to five leaves.

土壤干旱胁迫下沙棘休眠、萌芽期内源激素变化及外源GA_3的调节

研究了２年生中国沙棘（Ｈｉｐｐｏｐｈａｅ ｒｈａｍｎｏｉｄｓ）在土壤干旱胁迫下苗木含水量、内源激素水平与萌芽率关系以及萌芽关键期喷施外源ＧＡ３的作用。结果表明：土壤干旱胁迫使冬季休眠与春季萌芽期苗木含水量、内源ＧＡ１／３降低，内源ＡＢＡ明显提高，ＧＡ１／３ＡＢＡ下降，达到萌动所需的调控阈值的时间延迟，重度干旱下苗木萌芽延迟约２５ｄ，且萌芽后的枝生长十分缓慢；中度干旱下苗木萌芽延迟１０ｄ，萌芽后生长亦有所抑制。喷施８０ｍｇ／Ｌ外源ＧＡ３溶液可有效提高重度干旱下苗木内源ＧＡ１／３，降低ＡＢＡ含量，使ＧＡ１／３／ＡＢＡ提高，促进苗木提早萌芽及萌芽后生长；在适宜水分及中度干旱下，沙棘苗木外施ＧＡ３对萌芽及其生长作用不明显。

干旱对沙棘休眠、萌芽期内源激素及萌芽特性的影响

以 2a生中国沙棘为试验材料 ,研究了土壤干旱胁迫下沙棘苗木水分生理状况 ,内源GA1 3 及ABA水平与萌芽率的关系 ,结果表明 :土壤干旱胁迫导致苗体含水量、水势、自由水含量下降 ,显著提高冬季休眠与春季萌动期的内源ABA水平而降低内源GA1 3 含量 ,GA1 3 ABA降低 ,较晚达到萌动所需的调控阈值 ,萌芽延迟。重度胁迫下苗木延迟达 2 5d且萌芽后生长缓慢。长期土壤中度干旱条件下沙棘苗萌芽期亦略有延迟 ,萌芽后生长略有抑制

赤霉素、硫脲处理对黄精根状茎和须根发生的影响

为诱导无芽黄精根状茎产生不定芽,选择不同的化学物质进行诱导处理。结果表明,GA3处理效果明显,选用0.4 mg/L的GA3浸泡25 min对黄精根状茎不定芽的产生和须根生长有明显促进作用,高浓度抑制其生长;1%硫脲浸泡处理对黄精无顶芽根状茎萌发新芽和须根有明显的抑制作用。

容器苗质量评定指标的研究

In this paper,the assessing indices of container seedlings quality were synthesized in accordance with growth and physiological factors. The results showed that the seedling quality might be determined by the dormancy state of terminal bud,nutrient condition of plant,and the state of root system. The critical quality indices should include stem diameter at soil surface,dry weight of terminal bud,and soluble sugar content. Moreover,some indices such as root system vitality and dry weight of plant were also important.

Variation of active constituents of an important Tibet folk medicine Swertia mussotii Franch. (Gentianaceae) between artificially cultivated and naturally distributed

Concentrations of seven phytochemical constituents (swertiamarin, mangiferin, swertisin, oleanolic acid, 1,5,8-trihydroxy-3methoxyxanthone, 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethoxyxanthone) of "ZangYinChen" (Swertia mussotii, a herb used in Tibetan folk medicine) were determined and compared in plants collected from naturally distributed high-altitude populations and counterparts that had been artificially cultivated at low altitudes. Levels of mangiferin, the most abundant active compound in this herb, were significantly lower in cultivated samples and showed a negative correlation with altitude. The other constituents were neither positively nor negatively correlated with cultivation at low altitude. Concentrations of all of the constituents varied substantially with growth stage and were highest at the bud stage in the cultivars, but there were no distinct differences between flowering and fruiting stages in this respect. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

语前聋小儿人工耳蜗植入术后的言语康复

An Approach to the Rehabilitation of Prelingually Deaf Children After Cochlear Implantation Zheng Xiujin(Medical Psychology) Directed by Professor Yin WenGang Abstract Objective: To sum up the acquirement rule of speech and language capability which is for the prelingually deaf children after cochlear implantation by listening and language rehabilitation training and to investigate the factors that affect rehabilitation speed. Method: Sixty-four children received a cochlear implant at the age of 2 to 5 years from 2001 to 2005. They begin to be trained under group pattern after switch on 1 month. The whole training program lasted more than 7 months; after that, according to the teacher’s plan the training program was to be continued at home. Result: The period is 108±7.7 days that they can pronounce correctly 50 percent of all of simple-finals and compound-finals, the period is 115.0±7.8 days that they begin auditory repeating, the period is 135.3±10.9 days that they can speech the first specific word independently and the period is 200.3±13.9 days that they can speak 70 words and come into tri-gamut-word and two-word sentence period. The patient that is the group at the age of 2-3 years can take part in normal kindergarten after switch on about 10 months. There are no significant differences in various grades of speech-language development with different age groups and so do with different sex groups. There are significant differences in various grade of speech-language development with various IQ group (P<0.01) and so do with using and not using hearing aids before implantation. Conclusion: From the research we find that the speech and language development sequence is the same level between the prelingually deaf children of 2 to 5 years who received cochlear implant after speech training and normal children and which are stages of uncomplicated sound production, continuous syllabic (babbling), speech sprout, single-word utterances and two-word utterances in proper order. The time is short significantly and the reason is that cognition capability is enhanced along with the increase of age. The intelligence is main factor that affect rehabilitation speed and the speed in the group of high IQ is faster than common IQ. It is not because of the dominance cognition of the senior group that makes the increasing of the rehabilitation, it even makes slowly. The reason of which is that the senior group are exposed the language environment too late to achieve speech and language development. So we should perform an operation and training early. The effectiveness of rehabilitation after cochlear implantation is improved by using hearing aids before implantation. The reason is auditory stimulate can be benefit of to deaf children. The rehabilitation speeds in the children at the age of 2 to 5 years have nothing to do with sex. Key words: cochlear implant; speech therapy; paediatric rehabilitation