352 resultados para Tanshinone iia


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The regulation of human immunodeficiency virus type 1 (HIV-1) gene expression in response to Tat is dependent on an element downstream of the HIV-1 transcriptional initiation site designated the trans-activating region (TAR). TAR forms a stable stem-loop RNA structure in which a 3-nt bulge structure and a 6-nt loop structure are important for Tat activation. In the absence of Tat, the HIV-1 promoter generates so-called short or nonprocessive transcripts terminating at +60, while in the presence of Tat the synthesis of these short transcripts is markedly decreased and transcripts that extend through the 9.0-kb HIV-1 genome are synthesized. Tat effects on transcriptional elongation are likely due to alterations in the elongation properties of RNA polymerase II. In this study we demonstrated that a set of cellular cofactors that modulate the binding of the cellular protein TRP-185 to the TAR RNA loop sequences also functioned to markedly stimulate the specific binding of hypophosphorylated (IIa) and hyperphosphorylated (IIo) RNA polymerase II to TAR RNA. The concentrations of RNA polymerase II required for this interaction with TAR RNA were similar to those required to initiate in vitro transcription from the HIV-1 long terminal repeat. RNA gel retardation analysis with wild-type and mutant TAR RNAs indicated that the TAR RNA loop and bulge sequences were critical for the binding of RNA polymerase II. The addition of wild-type but not mutant Tat protein to gel retardation analysis with TAR RNA and RNA polymerase II resulted in the loss of binding of RNA polymerase II binding to TAR RNA. These results suggest that Tat may function to alter RNA polymerase II, which is paused due to its binding to HIV-1 TAR RNA with resultant stimulation of its transcriptional elongation properties.

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This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the diagnosis and management of nonvariceal upper gastrointestinal hemorrhage (NVUGIH). Main Recommendations MR1. ESGE recommends immediate assessment of hemodynamic status in patients who present with acute upper gastrointestinal hemorrhage (UGIH), with prompt intravascular volume replacement initially using crystalloid fluids if hemodynamic instability exists (strong recommendation, moderate quality evidence). MR2. ESGE recommends a restrictive red blood cell transfusion strategy that aims for a target hemoglobin between 7 g/dL and 9 g/dL. A higher target hemoglobin should be considered in patients with significant co-morbidity (e. g., ischemic cardiovascular disease) (strong recommendation, moderate quality evidence). MR3. ESGE recommends the use of the Glasgow-Blatchford Score (GBS) for pre-endoscopy risk stratification. Outpatients determined to be at very low risk, based upon a GBS score of 0 - 1, do not require early endoscopy nor hospital admission. Discharged patients should be informed of the risk of recurrent bleeding and be advised to maintain contact with the discharging hospital (strong recommendation, moderate quality evidence). MR4. ESGE recommends initiating high dose intravenous proton pump inhibitors (PPI), intravenous bolus followed by continuous infusion (80 mg then 8 mg/hour), in patients presenting with acute UGIH awaiting upper endoscopy. However, PPI infusion should not delay the performance of early endoscopy (strong recommendation, high quality evidence). MR5. ESGE does not recommend the routine use of nasogastric or orogastric aspiration/lavage in patients presenting with acute UGIH (strong recommendation, moderate quality evidence). MR6. ESGE recommends intravenous erythromycin (single dose, 250 mg given 30 - 120 minutes prior to upper gastrointestinal [GI] endoscopy) in patients with clinically severe or ongoing active UGIH. In selected patients, pre-endoscopic infusion of erythromycin significantly improves endoscopic visualization, reduces the need for second-look endoscopy, decreases the number of units of blood transfused, and reduces duration of hospital stay (strong recommendation, high quality evidence). MR7. Following hemodynamic resuscitation, ESGE recommends early (≤ 24 hours) upper GI endoscopy. Very early (< 12 hours) upper GI endoscopy may be considered in patients with high risk clinical features, namely: hemodynamic instability (tachycardia, hypotension) that persists despite ongoing attempts at volume resuscitation; in-hospital bloody emesis/nasogastric aspirate; or contraindication to the interruption of anticoagulation (strong recommendation, moderate quality evidence). MR8. ESGE recommends that peptic ulcers with spurting or oozing bleeding (Forrest classification Ia and Ib, respectively) or with a nonbleeding visible vessel (Forrest classification IIa) receive endoscopic hemostasis because these lesions are at high risk for persistent bleeding or rebleeding (strong recommendation, high quality evidence). MR9. ESGE recommends that peptic ulcers with an adherent clot (Forrest classification IIb) be considered for endoscopic clot removal. Once the clot is removed, any identified underlying active bleeding (Forrest classification Ia or Ib) or nonbleeding visible vessel (Forrest classification IIa) should receive endoscopic hemostasis (weak recommendation, moderate quality evidence). MR10. In patients with peptic ulcers having a flat pigmented spot (Forrest classification IIc) or clean base (Forrest classification III), ESGE does not recommend endoscopic hemostasis as these stigmata present a low risk of recurrent bleeding. In selected clinical settings, these patients may be discharged to home on standard PPI therapy, e. g., oral PPI once-daily (strong recommendation, moderate quality evidence). MR11. ESGE recommends that epinephrine injection therapy not be used as endoscopic monotherapy. If used, it should be combined with a second endoscopic hemostasis modality (strong recommendation, high quality evidence). MR12. ESGE recommends PPI therapy for patients who receive endoscopic hemostasis and for patients with adherent clot not receiving endoscopic hemostasis. PPI therapy should be high dose and administered as an intravenous bolus followed by continuous infusion (80 mg then 8 mg/hour) for 72 hours post endoscopy (strong recommendation, high quality evidence). MR13. ESGE does not recommend routine second-look endoscopy as part of the management of nonvariceal upper gastrointestinal hemorrhage (NVUGIH). However, in patients with clinical evidence of rebleeding following successful initial endoscopic hemostasis, ESGE recommends repeat upper endoscopy with hemostasis if indicated. In the case of failure of this second attempt at hemostasis, transcatheter angiographic embolization (TAE) or surgery should be considered (strong recommendation, high quality evidence). MR14. In patients with NVUGIH secondary to peptic ulcer, ESGE recommends investigating for the presence of Helicobacter pylori in the acute setting with initiation of appropriate antibiotic therapy when H. pylori is detected. Re-testing for H. pylori should be performed in those patients with a negative test in the acute setting. Documentation of successful H. pylori eradication is recommended (strong recommendation, high quality evidence). MR15. In patients receiving low dose aspirin for secondary cardiovascular prophylaxis who develop peptic ulcer bleeding, ESGE recommends aspirin be resumed immediately following index endoscopy if the risk of rebleeding is low (e. g., FIIc, FIII). In patients with high risk peptic ulcer (FIa, FIb, FIIa, FIIb), early reintroduction of aspirin by day 3 after index endoscopy is recommended, provided that adequate hemostasis has been established (strong recommendation, moderate quality evidence).

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The three hieroglyphic texts with transliteration and Italian translation.

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Some nos. have title: Annales littéraires de l'Université de Franche-Comté.

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Part of the illustrative matter is colored, part folded.

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Sometimes referred to as the Old series or first series.

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"Aus den Sitzungsberichten der Kaiserl. Akademie der Wissenschaften in Wien, Mathem.-naturw. Klasse, Abteilung IIa, 125. Band, 5. Heft."

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At head of title, 1916- : R. Università di Pisa.

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Mode of access: Internet.

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Editor: Flinders Petrie.

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Mode of access: Internet.

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Mode of access: Internet.

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Bibliographie: v. 5, v. 7.