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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.
Calciphylaxis – a topical overview   总被引:3,自引:0,他引:3  
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.  相似文献   
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The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
5.
Administration of supraphysiological doses of testosterone to normal men causes inhibition of spermatogenesis, but while most become azoospermic, 30-55% maintain a low rate of spermatogenesis. We have investigated whether there are differences in endogenous androgen production, of testicular and adrenal origin, which may be related to the degree of suppression of spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m. injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic, while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a specific testicular product, was reduced to <10% of pretreatment values, with no differences between the groups. Similar results were obtained for other markers of testicular steroidogenesis. Urinary and plasma adrenal androgens were also reduced during TE treatment: a statistically significant decrease in both (P < 0.001 and P < 0.05 respectively) was seen in the azoospermic but not oligozoospermic responders. These results suggest that testicular steroidogenesis is decreased to <10% by the administration of supraphysiological doses of exogenous testosterone. Differences in the degree of ongoing steroidogenesis in the testis do not appear to account for incomplete suppression of spermatogenesis, thus differences in androgen metabolism may underlie this heterogeneous response. A small but significant reduction in secretion of adrenal androgens was also detectable, the relevance of which is unclear.   相似文献   
6.
A locus for autosomal dominant anterior polar cataract on chromosome 17p   总被引:6,自引:3,他引:6  
Inherited cataract is a clinically and genetically heterogeneous disease. Here we report the identification of a new locus for an autosomal dominant anterior polar cataract on the short arm of chromosome 17. To map this new locus we performed genetic linkage analysis with microsatellite markers in a four-generation pedigree. After exclusion of seven candidate loci for cataract, we obtained significant positive LOD scores for markers D17S849 (Z = 4.01 / theta = 0.05) and D17S796 (Z = 4.17 / theta = 0.05). Multipoint analysis gave a maximum LOD score of 5.2 (theta max = 0.06) between these two markers. From haplotype analysis, the cataract locus lies in the 13 cM interval between markers D17S849 and D17S796. This study provides the first genetic mapping of an autosomal dominant anterior polar cataract.   相似文献   
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8.
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   
9.
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   
10.

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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