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71.
报道了越南木樨科(Oleaceae)植物1 新记录种大果素馨(Jasminum macrocarpum Merr.).该种产自越南中南部嘉来省的K’Bang, Kon Ha Nung 地区, 凭证标本保存在 HN, IBSC.  相似文献   
72.

Background

The Centers for Disease Control recommend screening for asymptomatic sexually transmitted infection (STI) among HIV-infected men when there is self-report of unprotected anal-receptive exposure. The study goals were: (1) to estimate the validity and usefulness for screening policies of self-reported unprotected anal-receptive exposure as a risk indicator for asymptomatic anorectal infection with Neisseria gonorrhoeae (GC) and/or Chlamydia trachomatis (CT). (2) to estimate the number of infections that would be missed if anal diagnostic assays were not performed among patients who denied unprotected anorectal exposure in the preceding month.

Methods and Findings

Retrospective analysis in HIV primary care and high resolution anoscopy (HRA) clinics. HIV-infected adult men were screened for self-reported exposure during the previous month at all primary care and HRA appointments. Four sub-cohorts were defined based on microbiology methodology (GC culture and CT direct fluorescent antibody vs. GC/CT nucleic acid amplification test) and clinical setting (primary care vs. HRA). Screening question operating characteristics were estimated using contingency table methods and then pooled across subcohorts. Among 803 patients, the prevalence of anorectal GC/CT varied from 3.5–20.1% in the 4 sub-cohorts. The sensitivity of the screening question for self-reported exposure to predict anorectal STI was higher in the primary care than in the HRA clinic, 86–100% vs. 12–35%, respectively. The negative predictive value of the screening question to predict asymptomatic anorectal STI was ≥90% in all sub-cohorts. In sensitivity analyses, the probability of being an unidentified case among those denying exposure increased from 0.4–8.1% in the primary care setting, and from 0.9–18.8% in the HRA setting as the prevalence varied from 1–20%.

Conclusion

As STI prevalence increases, denial of unprotected anal-receptive exposure leads to an increasingly unacceptable proportion of unidentified asymptomatic anorectal STI if used as a criterion not to obtain microbiologic assays.  相似文献   
73.

Background

A recent randomized placebo-controlled trial of the effect of atorvastatin treatment on the progression of newly diagnosed type 1 diabetes suggested a slower decline of residual beta cell function with statin treatment. Aim of this secondary analysis was to identify patient subgroups which differ in the decline of beta cell function during treatment with atorvastatin.

Methodology/Principal Findings

The randomized placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and detectable islet autoantibodies (mean age 30 years, 40% females), in 12 centers in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. For this secondary analysis patients were stratified by single baseline characteristics which were considered to possibly be modified by atorvastatin treatment. Subgroups defined by age, sex or by baseline metabolic parameters like body mass index (BMI), total serum cholesterol or fasting C-peptide did not differ in C-peptide outcome after atorvastatin treatment. However, the subgroup defined by high (above median) baseline C-reactive protein (CRP) concentrations exhibited higher stimulated C-peptide secretion after statin treatment (p = 0.044). Individual baseline CRP levels correlated with C-peptide outcome in the statin group (r2 = 0.3079, p<0.004). The subgroup with baseline CRP concentrations above median differed from the corresponding subgroup with lower CRP levels by higher median values of BMI, IL-6, IL-1RA, sICAM-1 and E-selectin.

Conclusions/Significance

Atorvastatin treatment may be effective in slowing the decline of beta cell function in a patient subgroup defined by above median levels of CRP and other inflammation associated immune mediators.

Trial Registration

ClinicalTrials.gov NCT00974740  相似文献   
74.
Dinocrocuta gigantea头骨的发现   总被引:3,自引:2,他引:3  
本文记述了甘肃和政县晚中新世地层中发现的一个完整的巨鬣狗头骨;讨论了它的分类地位,修正了 Schlosser 1903年建种时的一些鉴定错误.巨鬣狗是鬣狗科中一个十分特化的成员,应代表一个独立的属.根据命名规则,我们采用 N. schmidt-Kittler 1976年所创的 Dinocrocuta. 因此,这个种应订正为 Dinocrocuta gigantea (schlosser, 1903).  相似文献   
75.
Further analyses of the Medical Research Council''s trial of drug treatment of mild hypertension were carried out to provide more detailed information on the benefits associated with treatment in various subgroups. The four main considerations in establishing a rational treatment policy were, firstly, the significant reduction in the stroke rate with active treatment; secondly, the absence of a significant overall treatment effect on myocardial infarction; thirdly, the knowledge that of 100 untreated men in the highest risk group (those aged 55-64 with high systolic pressure at entry who smoked), five would be expected to suffer a stroke and 10 a coronary event within five years; and, fourthly, the cost, in clinical and financial terms, of prolonged treatment. In the high risk group of 100 men treatment with bendrofluazide would result in the prevention of three or four of the five strokes but would have little effect on the expected numbers of myocardial infarctions. Treatment with propranolol in non-smoking men in the highest age and blood pressure categories would lead to a reduction in the number having strokes from three to one or two and might possibly reduce the number experiencing myocardial infarction from seven to four. Smokers treated with propranolol would not be expected to benefit. In women avoiding smoking was particularly important. The considerations for preventing stroke were similar to those in men, but no clear guideline was possible on the effect of lowering blood pressure for preventing myocardial infarction in women.Drug treatment reduces the attack rate of certain events in mild hypertension but should not be prescribed routinely for all patients with the disorder.  相似文献   
76.
Lipopolysaccharide (LPS) is the major pathogen-associated molecular pattern of Gram-negative bacterial infections, and includes smooth (S-LPS) and rough (R-LPS) chemotypes. Upon activation by LPS through CD14, TLR4/MD-2 heterodimers sequentially induce two waves of intracellular signaling for macrophage activation: the MyD88-dependent pathway from the plasma membrane and, following internalization, the TRIF-dependent pathway from endosomes. We sought to better define the role of scavenger receptors CD36 and CD204/SR-A as accessory LPS receptors that can contribute to pro-inflammatory and microbicidal activation of macrophages. We have found that CD36 differently regulates activation of mouse macrophages by S-LPS versus R-LPS. The ability of CD36 to substitute for CD14 in loading R-LPS, but not S-LPS onto TLR4/MD-2 allows CD14-independent macrophage responses to R-LPS. Conversely, S-LPS, but not R-LPS effectively stimulates CD14 binding to CD36, which favors S-LPS transfer from CD14 onto TLR4/MD-2 under conditions of low CD14 occupancy with S-LPS in serum-free medium. In contrast, in the presence of serum, CD36 reduces S-LPS binding to TLR4/MD-2 and the subsequent MyD88-dependent signaling, by mediating internalization of S-LPS/CD14 complexes. Additionally, CD36 positively regulates activation of TRIF-dependent signaling by both S-LPS and R-LPS, by promoting TLR4/MD-2 endocytosis. In contrast, we have found that SR-A does not function as a S-LPS receptor. Thus, by co-operating with CD14 in both R- and S-LPS loading onto TLR4/MD-2, CD36 can enhance the sensitivity of tissue-resident macrophages in detecting infections by Gram-negative bacteria. However, in later phases, following influx of serum to the infection site, the CD36-mediated negative regulation of MyD88-dependent branch of S-LPS-induced TLR4 signaling might constitute a mechanism to prevent an excessive inflammatory response, while preserving the adjuvant effect of S-LPS for adaptive immunity.  相似文献   
77.

Background  

The guanine nucleotide exchange factor C3G (RapGEF1) along with its effector proteins participates in signaling pathways that regulate eukaryotic cell proliferation, adhesion, apoptosis and embryonic development. It activates Rap1, Rap2 and R-Ras members of the Ras family of GTPases. C3G is activated upon phosphorylation at tyrosine 504 and therefore, determining the localization of phosphorylated C3G would provide an insight into its site of action in the cellular context.  相似文献   
78.
79.

Introduction

Information about sepsis in mainland China remains scarce and incomplete. The purpose of this study was to describe the epidemiology and outcome of severe sepsis and septic shock in mixed ICU in mainland China, as well as the independent predictors of mortality.

Methods

We performed a 2-month prospective, observational cohort study in 22 closed multi-disciplinary intensive care units (ICUs). All admissions into those ICUs during the study period were screened and patients with severe sepsis or septic shock were included.

Results

A total of 484 patients, 37.3 per 100 ICU admissions were diagnosed with severe sepsis (n = 365) or septic shock (n = 119) according to clinical criteria and included into this study. The most frequent sites of infection were the lung and abdomen. The overall ICU and hospital mortality rates were 28.7% (n = 139) and 33.5% (n = 162), respectively. In multivariate analyses, APACHE II score (odds ratio[OR], 1.068; 95% confidential interval[CI], 1.027–1.109), presence of ARDS (OR, 2.676; 95%CI, 1.691–4.235), bloodstream infection (OR, 2.520; 95%CI, 1.142–5.564) and comorbidity of cancer (OR, 2.246; 95%CI, 1.141–4.420) were significantly associated with mortality.

Conclusions

Our results indicated that severe sepsis and septic shock were common complications in ICU patients and with high mortality in China, and can be of help to know more about severe sepsis and septic shock in China and to improve characterization and risk stratification in these patients.  相似文献   
80.
A precondition for the chemotherapeutic treatment of a variety of virally-induced human diseases and malignant conditions is a highly selective interaction of the drug molecule to be used with it's biological target. To ensure the development of novel, effective drugs, it is essential that the biological target is well characterised with regard to it's structure and activity. Such characterisation relies upon adequate amounts of pure target being available. One of the most important enzymatic importers for antimetabolites is the enzyme thymidine kinase. In this article an in vitro protein expression system is described which facilitates the production of milligram amounts of pure and biologically active thymidine kinase, from a number of important biological sources. Results have shown that the in vitro produced enzyme has the exact biochemical propeties of the in vivo enzyme. Thus the in vitro protein expression system is an ideal vechicle to facilitate an in depth investigation of the enzyme's biological properties.  相似文献   
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