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排序方式: 共有1783条查询结果,搜索用时 15 毫秒
1.
Laparoscopic cholecystectomy for left-sided gallbladder (sinistroposition).   总被引:1,自引:0,他引:1  
Transposition of the gallbladder to the left side without situs inversus viscerum is rare. These gallbladders are situated under the left lobe of the liver between Segment III and IV or on Segment III to the left of the falciform ligament. Because routine preoperative studies may not detect the anomaly, it may provide the surgeons with an unusual surprise during laparoscopy. Awareness of the unpredictable confluence of the cystic duct into the common bile duct and selective use of intraoperative cholangiography aid in the safe laparoscopic management of this unusual problem.  相似文献   
2.
Lithium and memory: a review   总被引:1,自引:0,他引:1  
This paper reviews systematic clinical studies suggesting memory and cognitive impairment in patients suffering from unipolar and bipolar affective disorders treated with lithium. A number of studies failed, however, to demonstrate lithium induced memory deficits. Thus, the results of studies were equivocal. This lack of empirical consensus was in part due to the heterogeneity of samples and a variety of methodological and design problems. The definition of short- and long-term memory was often arbitrary and lacked standard criteria. Some studies revealed a stability of the memory test scores over time and showed that subjective complaints of memory impairment were correlated with depression. The authors also reviewed studies examining the effects of lithium on cognition and memory of healthy control subjects. In animal research it was difficult at times to distinguish between toxic and pharmacologic effects of lithium. There is a need for prospective studies of the effect of lithium in large samples of patients using refined memory tests.  相似文献   
3.
To identify tobacco recidivism among 86 heart transplant recipients who were smokers but demonstrated compliance with a smoking cessation program pre-transplant, we used a questionnaire and randomly tested urine for nicotine and its by-products. In 36 patients, we also evaluated circulating levels of HS-CRP, homocysteine and MPV. Twenty-eight (32.5%) of 86 patients met our definition for tobacco exposure. In this cohort, 28 (32.5%) of 86 patients met our definition for tobacco exposure. Of these 28, 12 patients self-reported tobacco use and demonstrated biochemical verification; 14 patients demonstrated only biochemical evidence of significant tobacco exposure; 2 patients self-reported tobacco use but did not demonstrate biochemical positivity. Smoking cessation within 6 months of transplantation (r = 0.52) and time post-transplantation (r = 0.43) were independent predictors for recidivism of tobacco use, p < 0.01. No differences in HS-CRP, homocysteine and MPV levels were noted among the groups. Our investigation demonstrates a high rate of tobacco recidivism among heart transplant recipients, yet few admit to it. The adverse effects of tobacco do not appear to be directly modulated by an effect on athero-thrombotic risk markers.  相似文献   
4.
The T cell response against myelin basic protein (MBP) has been extensively studied in humans because of its putative role in the pathophysiology of multiple sclerosis (MS). Higher concordance rates in monozygous twins as well as an increased risk in relatives suggest the role of genetic factors in MS susceptibility. Very little is known about the shaping of T cell repertoire towards self antigens in humans and their contribution to disease susceptibility in autoimmune disorders. Here we report the comparative T cell epitope recognition patterns towards the MBP auto-antigen in healthy identical twins. We have established MBP-specific T cell lines from eight sets of twins and characterized their fine epitope specificity. Intra-pair comparison showed the co-existence of shared as well as distinct epitopes in six of eight pairs and a complete absence of concordant epitope recognition within two other pairs. These findings indicate that important differences in T cell repertoires against a self antigen may be observed between genetically identical healthy individuals, rendering difficult the interpretation of the differences which may be observed between identical twins discordant for an autoimmune disease.  相似文献   
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Memory B cells of mice with Ig mu transgenes often carry transgene copies that have moved into the Igh locus via somatic translocation. This phenomenon has been attributed to a selection pressure for somatic hypermutations, which generally are observed at much higher frequencies in translocated copies than in ectopic copies. We tested this idea by immunizing Ig-mu transgenic mice in a manner designed to select B cells that required only one V(H) mutation for a switch in antigenic specificity and recruitment into the memory pool. Despite the minimal mutation requirement, hybridomas carrying somatic translocations to the Igh locus were obtained. Importantly, this occurred despite the fact that translocated and untranslocated mu-transgenes were mutated comparably. Evidently, a strong selection advantage was conferred upon B cells by the somatic translocations. Among the hybridomas, translocated mu-transgenes were active, while ectopic mu-transgenes were uniformly silent. The translocated copy that had conferred an affinity-based selection advantage was expressed at the highest level. Moreover, translocated copies were differentially expressed among hybridoma members, which belonged to a common post-mutational lineage. This suggests that adjustments in transgene expression levels had occurred during memory cell development. These results indicate that, apart from their potential influences on somatic hypermutagenesis and class switch recombination, elements in the Igh locus promote the selection of memory B cells in another way, possibly by regulating the level of Ig expression at various stages of antigen-driven differentiation.  相似文献   
7.
BackgroundFractures of the proximal humerus represent approximately 4% of all fractures and 26% of humerus fractures. Proper reduction, stable internal fixation and early initiation of physiotherapy help to achieve a good functional outcome. Aim of this study was to evaluate varus fixation/malunion of proximal humerus fractures and its relation to functional outcome.Materials and MethodsWe retrospectively evaluated 32 patients with proximal humerus fractures who were surgically treated between 2015 and 2017 at tertiary care hospital. We divided the patients into three groups on the basis of the neck-shaft angle as valgus group, normal group and varus group to observe the influence of neck-shaft angle on efficacy. Patients were evaluated for functional outcome using the Constant–Murley score.ResultsTwo-part fractures had better functional outcome (Constant score = 75.15) compared to three parts with the moderate functional outcome (Constant score = 68.81) and the four-part fracture had poor functional outcome (Constant score = 52.66). After 6 months of follow-up, 13 patients had a neck-shaft angle of less than 126°. The functional outcome is significantly better among patients with normal neck-shaft angle and had a mean Constant score of 76.63 as compared to patients with varus deformity had a mean Constant score 60 (p = 0.001). 10 patients did not have medial support, in which 08 patients had neck-shaft angle less than 126° and 2 had a normal neck-shaft angle.ConclusionHigh fracture comminution, improper restoration of medial continuity causes varus deformity of the humeral head and it leads to poor functional outcome. The small sample size is the limitation of our study.  相似文献   
8.

The influence of fluctuating water temperature and dietary oxytetracycline (OTC) at 0 (0X), 80 (1X), 240 (3X), 400 (5X) and 800 mg (10X)/kg biomass/day for 30 consecutive days on the safety of monosex (all male) Nile tilapia Oreochromis niloticus fries in terms of feeding, growth, survival and histopathology of vital organs were assessed. A dose-dependent decline in feed intake and biomass was recorded. The OTC-dosed groups recorded higher mortalities than the control. The therapeutic OTC-dosing (1X) in conjunction with low temperature caused 75.56 ± 8.01% mortality and 25.75% reduced feed intake in 30 days. The mortalities increased with increasing OTC-doses from 85.19 ± 3.39% (1X) to 95.56 ± 2.22% (10X) and fluctuating temperature (12.00–21.50°C) even after the withdrawal of OTC. Relatively mild to moderate histopathological lesions were observed in the kidney, liver and intestine of OTC-dosed fries. These results suggested that dietary OTC and low water temperature may cause adverse effects on monosex O. niloticus fries.

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9.
Uterine cervical cancer is the most common malignancy among females in developing countries, including India. The success of cervical cancer screening programs in North America and Western Europe has been the result of centralized cervical-cytology screening. This is not possible in the villages (n=17,000) of Tamilnadu where 58 percent of females in rural areas are illiterate, health infrastructure is mediocre, and cervical cytology is unknow. The present study was undertaken to examine if the village health nurse (VHN) could be trained quickly to identify a cervical abnormality by visual inspection so that we could down stage the cancer to earlier stages, more amenable to treatment. VHNs also would be trained to take an adequate Pap smear. A total of 101 VHNs were trained in batches and returned to their villages. Within two years, 6,459 engible women in the study area were screened. The agreement between the gynecologists and the VHNs in identifying cancer among those with abnormal cervix was 95 percent, and 80 percent of the Pap smears taken by VHNs were adequate by WHO criteria, making the feasibility study highly successful.Authors are with The Cancer Institute (WIA), Adyar, Madras, Tamil Nadu,India. Address correspondence to Dr Gajalakshmi, Epidemiology Division and Cancer Registry, 18, Sardar Patel Road, Cancer Institute (WIA), Madras-600 036, Tamilnadu, India. This project was funded by the Indian Council of Medical Research, Government of India, New Delhi, India.520 Cancer Causes and Control. Vol 7. 1996  相似文献   
10.
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