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101.
Biogerontology - Increasing age has a major detrimental impact on female fertility, which, with an ageing population, has major sociological implications. This impact is primarily mediated through...  相似文献   
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Background

Bile leak following liver resection can be associated with significant morbidity. This systematic review and meta-analysis aims to evaluate the effect of intraoperative bile leak testing on postoperative bile leak rate and other complications after liver resection without biliary reconstruction for any cause.

Methods

PubMed, MEDLINE, Embase, Cochrane Library and grey literature databases were searched for articles between 1960 and 2017 comparing bile leak rates with or without bile leak testing. Standard meta-analysis methods were used. The primary outcome was bile leak rate, and secondary outcomes were overall morbidity, reintervention rate and length of stay.

Results

8 articles met inclusion criteria. Intraoperative bile leak testing after resection was associated with lower postoperative bile leak rate (4.1% vs 12.3%, OR 0.36, 95% CI 0.23–0.55, p < 0.001), overall morbidity (OR 0.67, 95% CI 0.47–0.96, p = 0.030), need for reintervention (OR 0.11, 95% CI 0.03–0.36, p < 0.001) and a shorter duration of hospital stay (2.21 days, 95% CI 0.69–3.73, p = 0.004).

Conclusion

The routine use of intraoperative bile leak testing during liver resection results in a significant reduction in postoperative bile leak rate, overall morbidity, length of hospital stay and need for re-intervention. Bile leak testing should be performed after liver resection without biliary reconstruction.  相似文献   
104.
Background : Viral kinetics suggests that daily administration of α‐interferon (IFN) will clear hepatitis C virus (HCV) RNA earlier and more frequently compared with standard t.i.w. To reduce the likelihood of viral replication, mutation and subsequent development of resistance, daily dosing with IFN may be appropriate. To determine the safety and efficacy of daily IFN with ribavirin in chronic HCV infection we performed a prospective study. Methods : Thirty‐five naïve adult HCV‐positive patients (25 male/10 female) were treated with IFN‐α2b; 5 MU daily for 2 weeks followed by 3 MU daily for 22 weeks and ribavirin 800–1200 mg/day depending on weight. Liver biopsy, performed in 25 patients, showed mild to moderate activity in 19 patients (76%) and severe activity in six patients (24%). Two patients showed staged IV fibrosis. Serotyping was performed in 29 patients by an enzyme immunoassay‐based Murex assay. Type 3 was the predominant serotype, present in 14 cases. Hepatitis C virus RNA was measured by the Chiron bDNA assay. Results : Mean baseline HCV‐RNA level was 14.2 ± 18.7 MEq/mL (median 6.09; range 0.2–92.5), which became undetectable in all but three patients at week 4. Normalization of alanine aminotransferase (ALT) at week 4 was seen in 27 patients. Three patients withdrew due to non‐compliance. Thirty‐two patients completed 24 weeks of therapy as per the protocol. At the end of treatment, the HCV‐RNA level was negative in 29 of 32 patients (90.6%) and ALT was normal in 31 of 32 patients (97%). Sustained viral response at 6 months follow up was seen in 28 of 32 patients (88%). The ALT level was normal in 28 of 32 patients (88%). Conclusion : Daily administration of IFN with ribavirin is well tolerated in the majority of patients. There is rapid elimination of virus with normalization of ALT and a significantly high sustained viral response. © 2002 Blackwell Publishing Asia Pty Ltd  相似文献   
105.
Abstract

The aim of this study was to estimate the effect of ambient air pollutants on cardiovascular deaths in Tehran, Iran. In this time series study, air pollutant data were acquired from the Environmental Protection Agency. Meteorological data were acquired from the meteorological organization, and death data were acquired from the Tehran’s cemetery registration. Generalized Additive Models (GAM) were used for estimating the Rate Ratio. NO2, SO2 and PM10 were associated with total cardiovascular deaths. PM10 and NO2 showed stronger relations with deaths in the elder age group. The result of this study showed that NO2, SO2, PM10 and O3 are probably responsible for part of the cardiovascular deaths that happen daily in Tehran.  相似文献   
106.
Nanobodies for the first time were identified in the sera of Camelidae. Single-domain antibodies or nanobodies are a class of next-generation antibodies that have specific features: small size (in nanoscale), high penetration in various tissues, high stability in hard situations and ease production process in microbial systems. In fact single-domain antibodies are the smallest fragment of the antibody with binding ability. Unique characteristics and features of nanobodies make them an appropriate candidate for further evaluation as the development of novel antibody-based therapeutics. In this regard single-domain antibodies are in the interest of many researchers as well as biopharmaceutical companies for diagnostic and therapeutic applications. Nowadays several single domain antibodies have been developed and evaluated in different clinical trials. Because of many advantages of single-domain antibodies over other formats of antibodies, they could be good replacement for other formats of antibodies in near future. Here, we review the biology, engineering platforms and application of nanobodies.  相似文献   
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Hepatitis C Virus (HCV) is a major etiological agent of chronic hepatitis, cirrhosis and hepatocellular carcinoma. Fas-mediated apoptosis is the major cause of hepatocyte damage during liver disease. The present work was performed to study the fas system (Fas-FasL and soluble Fas) in chronic hepatitis C infection. Also, to correlate the degree of liver cell damage with the Fas system. The study was carried out on 45 patients positive for HCV RNA by nested RT-PCR in addition to 13 HCV negative control subjects. Wedge liver biopsies samples were obtained from patients and controls during abdominal operations for determination of cellular expression of Fas and Fas-L on hepatocytes and infiltrating lymphocytes respectively by flow cytometry. Histological activity index (HAI) was determined in chronic HCV patients. Also blood samples were taken from patients and controls for determination of sFas. There was statistically insignificant difference in Fas expression in hepatocytes of patients (P?=?0.34) in comparison to control. Meanwhile, there was a statistically significant decrease in FasL expression in patients compared to control (P< 0.001) and statistically significant increase in soluble Fas in patients compared to control (P < 0.001). The HAI of liver fibrosis for all patients were within mild score with mean ± SD 4 ± 0.5. From this study, we could conclude that Fas system is one of the important pathways regulating the response to HCV infection. Increased serum sFas in HCV patients is accompanied by down-regulation of Fas/Fas-L expression resulting in inhibition of apoptosis in liver cells as a process for elimination of virus infected cells and this may ultimately leads to chronicity of the disease.  相似文献   
110.
IntroductionEndothelin-1 (ET-1) is the most potent among all vasoconstrictors, and its association with cardiovascular diseases has been reported before. Our aim was to investigate the association of ET-1 plasma level and its gene polymorphisms (rs5370 and rs10478694) with hypertension and coronary atherosclerosis (CA).Material and methodsThis study was carried out on 128 women and 132 men, who were divided into 4 groups: hypertensive without atherosclerosis (H+A–); hypertensive with atherosclerosis (H+A+); non-hypertensive with atherosclerosis (H–A+); and non-hypertensive without atherosclerosis (control group). Endothelin-1 plasma levels were measured by ELISA, and gene polymorphisms were detected by polymerase chain reaction – restriction fragment length polymorphism (PCR-RFLP) methods. Coronary artery diseases (CAD) were then defined based on angiography data.ResultsThe ET-1 plasma level was significantly higher in the H+A+ group in comparison with the other groups, especially H+A–. Comparing people with CA and those without it, the highest frequency level of the T allele of rs5370 was found in people with CA. Significantly higher frequencies of the 3A allele were detected in hypertensive patients in comparison with non-hypertensive individuals, when analyzing rs10478694.ConclusionsEndothelin-1 plasma level shows a direct association with the risk of CA development. The T allele of rs5370 can be regarded as a risk factor for CA development. The 3A allele of rs10478694 can be associated with the risk of hypertension; therefore, it can be concluded that ET-1 and its gene polymorphisms play an important role in CA development and hypertension observed in the south-eastern populations of Iran.  相似文献   
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