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991.
1期精原细胞瘤行睾丸切除术后的处理包括辅助放疗、化疗,或者进行随访观察。虽然随访的具体内容尚未明确,但是通常包括反复的胸片及腹部、盆腔CT(CT—AP)检查。为了评估胸片在随访中的价值,作者对玛嘉烈医院1982年至2005年间527例确诊为1期睾丸精原细胞瘤并获得随访的患者进行了分析。  相似文献   
992.
Sun JL, Sung MS, Huang MY, Cheng GC, Lin CC. Effectiveness of acupressure for residents of long‐term care facilities with insomnia: a randomized controlled trial. Int J Nurs Stud 2010; 47: 798–805.  相似文献   
993.

BACKGROUND AND PURPOSE

The cannabinoid CB1 receptor is primarily thought to be functionally coupled to the Gi form of G proteins, through which it negatively regulates cAMP accumulation. Here, we investigated the dual coupling properties of CB1 receptors and characterized the structural determinants that mediate selective coupling to Gs and Gi.

EXPERIMENTAL APPROACH

A cAMP-response element reporter gene system was employed to quantitatively analyze cAMP change. CB1/CB2 receptor chimeras and site-directed mutagenesis combined with functional assays and computer modelling were used to determine the structural determinants mediating selective coupling to Gs and Gi.

KEY RESULTS

CB1 receptors could couple to both Gs-mediated cAMP accumulation and Gi-induced activation of ERK1/2 and Ca2+ mobilization, whereas CB2 receptors selectively coupled to Gi and inhibited cAMP production. Using CB1/CB2 chimeric receptors, the second intracellular loop (ICL2) of the CB1 receptor was identified as primarily responsible for mediating Gs and Gi coupling specificity. Furthermore, mutation of Leu-222 in ICL2 to either Ala or Pro switched G protein coupling from Gs to Gi, while to Ile or Val led to balanced coupling of the mutant receptor with Gs and Gi.

CONCLUSIONS AND IMPLICATIONS

The ICL2 of CB1 receptors and in particular Leu-222, which resides within a highly conserved DRY(X)5PL motif, played a critical role in Gs and Gi protein coupling and specificity. Our studies provide new insight into the mechanisms governing the coupling of CB1 receptors to G proteins and cannabinoid-induced tolerance.  相似文献   
994.

Background and purpose:

Recent findings suggest that the noxious gas H2S is produced endogenously, and that physiological concentrations of H2S are able to modulate pain and inflammation in rodents. This study was undertaken to evaluate the ability of endogenous and exogenous H2S to modulate carrageenan-induced synovitis in the rat knee.

Experimental approach:

Synovitis was induced in Wistar rats by intra-articular injection of carrageenan into the knee joint. Sixty minutes prior to carrageenan injection, the rats were pretreated with indomethacin, an inhibitor of H2S formation (dl-propargylglycine) or an H2S donor [Lawesson''s reagent (LR)].

Key results:

Injection of carrageenan evoked knee inflammation, pain as characterized by impaired gait, secondary tactile allodynia of the ipsilateral hindpaw, joint swelling, histological changes, inflammatory cell infiltration, increased synovial myeloperoxidase, protein nitrotyrosine residues, inducible NOS (iNOS) activity and NO production. Pretreatment with LR or indomethacin significantly attenuated the pain responses, and all the inflammatory and biochemical changes, except for the increased iNOS activity, NO production and 3-NT. Propargylglycine pretreatment potentiated synovial iNOS activity (and NO production), and enhanced macrophage infiltration, but had no effect on other inflammatory parameters.

Conclusions and implications:

Whereas exogenous H2S delivered to the knee joint can produce a significant anti-inflammatory and anti-nociceptive effect, locally produced H2S exerts little immunomodulatory effect. These data further support the development and use of H2S donors as potential alternatives (or complementary therapies) to the available anti-inflammatory compounds used for treatment of joint inflammation or relief of its symptoms.  相似文献   
995.
996.
美国心脏协会卒中委员会发布了关于急性缺血性卒中的现行治疗指南,其中包括应用重组组织型纤溶酶原激活物(rt—PA)行静脉溶栓的建议。尽管该药对改善神经功能预后有一定的疗效,但由于患者通常在发病3h后方能到达医院,往往已经超过了用药的时间窗。因此,大部分缺血性卒中患者未能接受rt—PA治疗。目前研究认为,增加rt—PA治疗例数的最可能方法就是延长治疗时间窗。  相似文献   
997.

Background  

The purpose of this study was to explore women's views of the design of a large pragmatic cost-effectiveness randomised controlled trial of the policy of offering a health professional-delivered intervention to promote early presentation with breast symptoms in older women and thereby improve survival, with a view to informing protocol development. The trial will recruit over 100,000 healthy women aged 67+, and outcome data will be collected on those who develop breast cancer. The scale of the trial and the need for long-term follow-up presented a number of design challenges in relation to obtaining consent, ascertaining and contacting participants who developed breast cancer, and collecting outcome data.  相似文献   
998.
孕早期阴道B超引导下多胎妊娠胚胎抽吸减胎术5例   总被引:2,自引:0,他引:2  
1临床资料唐都医院妇产科在2003-09/2005-02间接受辅助生殖技术助孕后发生多胎妊娠的不孕症患者5例,年龄24~34岁,在孕6~8 wk进行减胎术.术前夫妇双方签署知情同意书.  相似文献   
999.
冠脉旁路移植术后康复1018例   总被引:1,自引:0,他引:1  
闫军兰 《医学争鸣》2005,26(10):933-933
1临床资料 1997-01/2004-12我院共完成冠脉旁路移植术(coronary artery bypass graft,CABG)1018(男888,女130)例,60岁以上582例(57.1%),70岁以上217例(21.3%),最大年龄86岁;非体外循环冠状动脉旁路移植术(OPCAB)510例,体外循环下冠状动脉旁路移植术(CCABG)508例;不稳定性心绞痛852例,术前同时合并其他疾病784例(77.1%),高血压病500例,  相似文献   
1000.
Worldwide, gastric cancer is one of the most common forms of cancer, with a high morbidity and mortality. Several environmental factors predispose to the development of gastric cancer, such as Helicobacter pylori infection, diet and smoking. Familial clustering of gastric cancer is seen in 10% of cases, and approximately 3% of gastric cancer cases arise in the setting of hereditary diffuse gastric cancer (HDGC). In families with HDGC, gastric cancer presents at relatively young age. Germline mutations in the CDH1 gene are the major cause of HDGC and are identified in approximately 25-50% of families which fulfill strict criteria. Prophylactic gastrectomy is the only option to prevent gastric cancer in individuals with a CDH1 mutation. However, in the majority of families with multiple cases of gastric cancer no germline genetic abnormality can be identified and therefore preventive measures are not available, except for general lifestyle advice. Future research should focus on identifying new genetic predisposing factors for all types of familial gastric cancer.  相似文献   
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