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OBJECTIVE--To compare the ability of angiotensin converting enzyme inhibitors and beta blockers to slow the development of end stage renal failure in non-diabetic patients with chronic renal failure. DESIGN--Open randomised multicentre trial with three year follow up. SETTING--Outpatient departments of six French hospitals. PATIENTS--100 hypertensive patients with chronic renal failure (initial serum creatinine 200-400 mumol/l. 52 randomised to enalapril and 48 to beta blockers (conventional treatment). INTERVENTIONS--Enalapril or beta blocker was combined with frusemide and, if necessary, a calcium blocker or centrally acting drug in patients whose diastolic pressure remained above 90 mm Hg. RESULTS--17 patients receiving conventional treatment and 10 receiving enalapril developed end stage renal failure. The cumulative renal survival rate was significantly better in the enalapril group than in the conventional group (P < 0.05). The slope of the reciprocal serum creatinine concentration was steeper in the conventionally treated patients (-6.89 x 10(-5)l/mumol/month) than in the enalapril group (-4.17 x 10(-5)l/mumol/month; P < 0.05). No difference in blood pressure was found between groups. CONCLUSION--In hypertensive patients with chronic renal failure enalapril slows progression towards end stage renal failure compared with beta blockers. This effect was probably not mediated through controlling blood pressure.  相似文献   
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中水技术开发既可缓解水资源的紧缺,又能改善城市环境。本文报道用石英粉吸附/洗脱和浓缩棒脱水的二步浓集水病毒技术(回收率为25.4~37.3%),研究中水技术不同处理工艺去除病毒的效果。结果,二级处理可去除掺入病毒的98.9%,结合三级处理的混凝沉淀和过滤,可去除99.976%,再加活性炭吸附或加氯消毒,所得中水分别去除掺入病毒的99.986%和99.991%。经首都机场中水道试验厂水样检测表明,中水中未检测到病毒(<0.23PFU/L)。  相似文献   
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本文在首次报告二例肺结核、糖尿病患者合并感染肺微小根毛霉的基础上,进一步探讨免疫功能受损与微小根毛霉感染关系。本文采用不同剂量~(60)Co-γ全身辐照小鼠,然后以不同途径注射同剂量的微小根毛霉的孢囊孢子,观察动物的感染情况和感染后的真菌检出率,结果发现各种辐射剂量均在辐射后7-14日感染菌的检出率最高;各种脏器感染菌的检出率以脾脏最高(66.7—81.8%);淋巴结最低(0.0—25.0%);其他脏器的感染菌检出率也有不同程度的差异。  相似文献   
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Applied Microbiology and Biotechnology - Butyric acid fermentation by Clostridium couples with the synthesis of acetic acid. But the presence of acetic acid reduces butyric acid yield and increases...  相似文献   
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Sorghum is largely grown for food, fodder and for biofuel production in semi-arid regions where the drought or high temperature or their combination co-occur. Plant microRNAs (miRNAs) are integral to the gene regulatory networks that control almost all biological processes including adaptation to stress conditions. Thus far, plant miRNA profiles under separate drought or heat stresses have been reported but not under combined drought and heat. In this study, we report miRNA profiles in leaves of sorghum exposed to individual drought or heat or their combination. Approximately 29 conserved miRNA families represented by 80 individual miRNAs, 26 families represented by 47 members of less conserved or sorghum-specific miRNA families as well as 8 novel miRNA families have been identified. Of these, 25 miRNAs were found to be differentially regulated in response to stress treatments. The comparative profiling revealed that the miRNA regulation was stronger under heat or combination of heat and drought compared to the drought alone. Furthermore, using degradome sequencing, 48 genes were confirmed as targets for the miRNAs in sorghum. Overall, this study provides a framework for understanding of the miRNA-guided gene regulations under combined stresses.

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Ptk2b has been found playing critical roles in oocyte maturation and subsequent fertilization in vitro. But what is the exact in vivo function in reproduction still elusive. Here, by constructing Ptk2b mutant mice, we found Ptk2b was not essential for mice fertility, unexpectedly, contrary to previously reported in vitro findings, we found Ptk2b ablation significantly improved female fecundity. Follicle counting indicated that the number of primordial follicles and growing follicles in matured mice was significantly increased in the absence of Ptk2b, whereas the primordial follicle formation showed no defects. We also found this regulation was in an autophosphorylation independent pathway, as autophosphorylation site mutant mice (PTK2BY402F) show no phenotype in female fertility. Further biochemistry studies revealed that Ptk2b ablation promotes folliculogenesis via Erk pathway mediate follicle survival. Together, we found a novel biological function of Ptk2b in folliculogenesis, which could be potentially used as a therapeutic target for corresponding infertility.  相似文献   
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To minimize the side effect of chemotherapy, a novel reduction/pH dual-sensitive drug nanocarrier, based on PEGylated dithiodipropionate dihydrazide (TPH)-modified hyaluronic acid (PEG-SS-HA copolymer), was developed for targeted delivery of doxorubicin (DOX) to hepatocellular carcinoma. The copolymer was synthesized by reductive amination via Schiff's base formation between TPH-modified HA and galactosamine-conjugated poly(ethylene glycol) aldehyde/methoxy poly(ethylene glycol) aldehyde. Conjugation of DOX to PEG-SS-HA copolymer was accomplished through the hydrazone linkage formed between DOX and PEG-SS-HA, and confirmed by FTIR and 1H NMR spectra. The polymer–DOX conjugate could self-assemble into spherical nanoparticles (∼150 nm), as indicated by TEM and DLS. In vitro release studies showed that the DOX-loaded nanoparticles could release DOX rapidly under the intracellular levels of pH and glutathiose. Cellular uptake experiments demonstrated that the nanoparticles could be efficiently internalized by HepG2 cells. These results indicate that the PEG-SS-HA copolymer holds great potential for targeted intracellular delivery of DOX.  相似文献   
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