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781.

Background

Although every step in the in vitro fertilisation (IVF) procedure is important, the impact of embryo transfer (ET) on pregnancy rate (PR) is significant. Of all the crucial aspects of ET the type of catheter used and the technique of transfer on the PR has drawn the maximum attention and controversy. We aimed to compare the outcome of two different ET catheters on the PR.

Method

A prospective analysis comparing the classical Frydman (Laboratoire CCD, France) and the soft Cook (Cook Medical, Indiana, USA) ET catheters was performed. Primary end-point was clinical pregnancy rate (CPR); secondary end-points were rates of difficult transfer. A total of 1,446 ETs were performed in women undergoing IVF treatment, of which 723 cycles were randomised to the Cook catheter and 723 to the Frydman catheter.

Results

It was observed that, although the Cook catheter was related to a slightly higher PR, the overall comparison failed to indicate a significant difference in CPR. It was also seen that the ease of transfer did not significantly affect the PRs.

Conclusion

Individual variables during ET may not contribute significantly to the success of an IVF programme; however, a holistic approach encompassing all the factors is quintessential to improve the PR.  相似文献   
782.
Epidemiological studies demonstrated that even in the absence of other risk factors (e.g., diabetes, hypertension, hypercholesterolemia), vascular aging significantly increases cardiovascular morbidity. Previous studies revealed that vascular aging is characterized by an age-dependent decline in endothelial function due to a decreased bioavailability of NO and increased production of reactive oxygen species. Yet, the mechanisms underlying the process of vascular aging are still poorly understood. Many authors consider that aging is a mitochondrial disease. Indeed, there is evidence that aging is associated with an increase in mtDNA damage and a decline in expression/activity of mitochondrial enzymes in various organs. On the basis of recent observations we predict that similar changes in mitochondrial gene expression profile are present in the aged cardiovascular system as well. It is significant, that components of the electron transport chain (including cytochrome c oxidase) seem to be similarly down-regulated with age in many species. Because pharmacological inhibition of mitochondrial energy metabolism significantly impairs endothelium-dependent vascular relaxation and may increase the production of reactive oxygen species, we propose that alterations of mitochondrial energetic phenotype may contribute to endothelial dysfunction in aging.  相似文献   
783.
784.
785.
Are sirtuins viable targets for improving healthspan and lifespan?   总被引:1,自引:0,他引:1  
Although the increased lifespan of our populations illustrates the success of modern medicine, the risk of developing many diseases increases exponentially with old age. Caloric restriction is known to retard ageing and delay functional decline as well as the onset of disease in most organisms. Studies have implicated the sirtuins (SIRT1-SIRT7) as mediators of key effects of caloric restriction during ageing. Two unrelated molecules that have been shown to increase SIRT1 activity in some settings, resveratrol and SRT1720, are excellent protectors against metabolic stress in mammals, making SIRT1 a potentially appealing target for therapeutic interventions. This Review covers the current status and controversies surrounding the potential of sirtuins as novel pharmacological targets, with a focus on SIRT1.  相似文献   
786.
The aim of this study was to assess Chinese schizophrenia patients' quality of life (QOL) and identify its demographic and clinical correlates. A random sample of 540 community-dwelling schizophrenia patients was interviewed using standardized assessment instruments. The patients' basic sociodemographic and clinical data and QOL were collected. Compared with the general population, patients had significantly lower scores in the physical and psychological QOL domains. Multivariate analyses showed that better social support independently predicted higher QOL in all domains, whereas more severe positive symptoms predicted worse psychological and environmental domains. Overall psychopathology predicted both worse physical and psychological domains; depressive symptoms and being married predicted worse physical and social QOL, respectively. Our results suggest that therapeutic and psychosocial interventions alleviating positive and depressive symptoms and improving poor social support and marriage-related problems in Chinese patients with schizophrenia might be of considerable benefit in improving their QOL.  相似文献   
787.
788.

Background

This study retrospectively analyses the initial experience of liver transplantation (LT) in the Indian Armed Forces.

Methods

Fifty-three patients underwent LT at Army Hospital (R&R) Delhi Cantt. between March 2007 and March 2011. Of these 35 patients underwent deceased donor liver transplantation (DDLT) and living donor liver transplantation (LDLT) was carried out in 18 patients. The surgical techniques, complications and mortality were analysed.

Results

A high consent rate of 35.9% for organ donation was achieved by the Armed Forces Organ Retrieval and Transplantation Authority (AORTA). Biliary complications occurred in five patients (9.4%). However, most of them could be managed by endoscopic interventions. Hepatic artery thrombosis (HAT) occurred in five patients (9.4%). Of these, two DDLT grafts were revascularised following HAT, by creating extra-anatomic arterial conduits with excellent outcome. The overall mortality was 18.8% (n = 10). There was no significant difference in the overall complications or mortality in patients undergoing DDLT or LDLT.

Conclusion

The overall survival and morbidity in this study is comparable to those from other centres. Urgent revascularisation of grafts following HAT should be attempted as it can salvage grafts with satisfactory outcome. There is a reduction in the incidence of biliary complications with refinements in surgical techniques.  相似文献   
789.
以豚鼠离体回肠和结肠带为标本,观察蛇床子素(Ost)的作用与Ca~(2+)的关系。结果表明:Ost和钙拮抗剂Ver产生剂量依赖性抑制乙酰胆碱(ACh)、组胺及KCl所致回肠条或结肠带的收缩;非竞争性拮抗CaCl_2累积量—效曲线,pD_2分别为4.41±0.15,7.0±0.2。Ost 100μmol/L和Ver 1μmol/L均能对抗小剂量Ca~(2+)所致结肠带收缩,但被加入较大量Ca~(2+)所取消。Ost和Ver均能抑制ACh诱导的依内钙性收缩,不影响依外钙性收缩。结果提示Ost具有钙拮抗作用,其作用方式与Ver类似。  相似文献   
790.
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