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71.
皮肤穿支血管的解剖学研究   总被引:18,自引:6,他引:18  
目的:对全身皮肤血管区域进行定性和定量分析,确定全身皮肤穿支血管的位置、数量、口径、穿支蒂的长度、类型、来源血管以及穿支所供应皮肤的面积,为穿支皮瓣提供血管解剖基础。方法:选用10具新鲜尸体,采用改良氧化铅一明胶灌注技术进行动脉灌注。将每个口径大于0.5mm的穿支血管进行解剖并记录。拍摄X线片以显示皮肤内血管的形态和分布。定量数据分析包括全身各部位的穿支血管的数量、口径、类型及其供应区域的面积。结果:发现全身128支起源血管发出440支穿支供应皮肤。其中肌皮穿支与肌间隔穿支之比为3:2。穿支平均直径为0.7mm。穿支血管的分布规律如下:①躯干皮肤的血供主要来自肌皮穿支,这些穿支在皮肤内的走行距离和分布范围大于肢体皮肤的穿支。②肢体皮肤的血供主要来自肌间隙穿支血管,主要分布在深筋膜表面,皮神经和浅静脉周围穿支之间形成链式血管吻合。③单位面积的穿支数量与皮肤的移动程度成反比,穿支的口径大小和穿支在皮肤内走行距离与皮肤移动度成正比,与穿支的供应面积成正比。结论:本研究提供详细的皮肤穿支血管解剖数据,为临床设计应用穿支皮瓣提供解剖学依据。  相似文献   
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Handedness is a basic property of spirals. In many cases it is possible to determine whether spiral fractures are right or left handed by analysis of radiographs. Spiral fractures of the tibia show striking bilateral symmetry, with right-handed spirals predominating on the left side of the body, and left-handed spirals on the right.  相似文献   
75.
AimRates of simultaneous liver and kidney transplantation (SLKT) have increased, but indications for SLKT remain poorly defined. Additional data are needed to determine which patients benefit from SLKT to best direct use of scarce donor kidneys.MethodsData were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) database for all SLKT performed until the end of 2017. Patients were divided by pretransplant dialysis status into no dialysis before SLKT (preemptive kidney transplant) and any dialysis before SLKT (nonpreemptive). Baseline characteristics and outcomes were compared.ResultsBetween 1989 and 2017, inclusive, 84 SLKT procedures were performed in Australia, of which 24% were preemptive. Preemptive and nonpreemptive SLKT recipients did not significantly differ in age (P = .267), sex (P = .526), or ethnicity (P = .870). Over a median follow-up time of 4.5 years, preemptively transplanted patients had a statistically equivalent risk of kidney graft failure (hazard ratio (HR) 1.83, 95% confidence interval [CI]: 0.36-12.86, P = .474) and all-cause mortality (HR 1.69, 95% CI: 0.51-5.6, P = .226) compared to nonpreemptive patients. Overall, 1- and 5-year survival rates for all SLKTs were 92% (95% CI: 86-96) and 60% (95% CI: 45-75), respectively.ConclusionKidney graft and overall patient survival were similar between patients with preemptive kidney transplant and those who were dialysis dependent.  相似文献   
76.
Skeletal homeostasis critically depends on the proper anabolic functioning of osteolineage cells. Proliferation and matrix synthesis are highly demanding in terms of biosynthesis and bioenergetics, but the nutritional requirements that support these processes in bone-forming cells are not fully understood. Here, we show that glutamine metabolism is a major determinant of osteoprogenitor function during bone mass accrual. Genetic inactivation of the rate-limiting enzyme glutaminase 1 (GLS1) results in decreased postnatal bone mass, caused by impaired biosynthesis and cell survival. Mechanistically, we uncovered that GLS1-mediated glutamine catabolism supports nucleotide and amino acid synthesis, required for proliferation and matrix production. In addition, glutamine-derived glutathione prevents accumulation of reactive oxygen species and thereby safeguards cell viability. The pro-anabolic role of glutamine metabolism was further underscored in a model of parathyroid hormone (PTH)-induced bone formation. PTH administration increases glutamine uptake and catabolism, and GLS1 deletion fully blunts the PTH-induced osteoanabolic response. Taken together, our findings indicate that glutamine metabolism in osteoprogenitors is indispensable for bone formation. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Sociosexuality and sexual compulsivity predict sex differences in voyeuristic interest in the population. In this study, we used a sample of 1113 participants from the UK (46% men) to consider whether sociosexuality and sexual compulsivity interacted to explain these sex differences and whether this relationship extended to the related domain of exhibitionism. In doing so, we tested novel predictions derived from an evolutionary perspective which views voyeuristic and exhibitionistic interest as manifestations of a short-term mating strategy. Participants reported their levels of repulsion toward voyeurism and exhibitionism and their interest in performing such acts under different levels of risk. There were clear sex differences in voyeuristic and exhibitionistic repulsion that were partially mediated by the serial combination of sociosexuality and sexual compulsivity. Examining the sexes separately revealed qualitatively different relationships between sociosexuality and sexual compulsivity when predicting exhibitionistic, but not voyeuristic, repulsion. Combined, sociosexuality and sexual compulsivity also mediated the sex difference in willingness to commit acts of voyeurism, but not exhibitionism, which was equally low for both sexes. The results highlight the role sociosexuality plays in voyeuristic and exhibitionistic interest, which coupled with an evolutionary perspective, may have implications for how we view courtship disorders.

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79.
Dexniguldipine-HCl (DNIG) — a prospective clinical modulator of p170-glycoprotein (pgp170)-mediated multidrug resistance (MRD) — was evaluated in a drug-accumulation assay in MDR murine leukemia cell strain F4-6RADR expressing pgp170. The compound elevated low accumulation of either doxorubicin (DOX), daunorubicin (DNR), or mitoxantrone (MITO) in resistant F4-6RADR cells to the very levels observed in drug-sensitive F4-6 precursor cells. In parallel with the increase in DNR content (F4-6RADR, solvent: 303±27 pmol/mg protein; DNIG (3.3 mol/l): 1,067±174 pmol/mg protein; F4-6P, solvent: 948±110 pmol/mg protein;n=8–9, SEM), the amount of DNR tightly bound to the acid precipitate pellet obtained from F4-6RADR (i.e., protein, DNA, RNA) increased 3.9-times to the levels observed in sensitive F4-6 cells. The main pyridine metabolite of DNIG displayed similar activity. Concentration-response analysis revealed that DNIG and R,S-verapamil (VER) induced 100% reversal of the DNR accumulation shortage associated with the MDR phenotype but DNIG was 8 times more potent than VER (50% inhibitory concentration (IC50), 0.73 vs 5.4 mol/l). In keeping with the accumulation assay, DNIG was about 10 times more potent than VER in sensitizing F4-6RADR cells to the cytostatic and cytotoxic effects of DNR in proliferation assays. In conclusion, DNIG is a potent in vitro modulator, improving (a) the accumulation of anthracycline-like cytostatics, (B) drug access to cellular binding sites, and (c) the cytostatic action of DNR in F4-6RADR leukemia cells of the MDR phenotype.Abbreviations DOX doxorubicin - CSA cyclosporin A - DMSO dimethylsulfoxide - DNIG dexniguldipine-HCl - DNR daunorubicin - MDR multidrug resistance - MITO mitoxantrone - pgp170 permease glycoprotein 170 - VER R.S.-verapamil Dexniguldipine-HCl is the proposed INN for compound B859-35, the R-enantiomer of niguldipine. Segments of this work have been reported in the abstract form  相似文献   
80.
Rationale: A novel scheme for the synthesis of cocaine analogs from vinylcarbenoid precursors has made available compounds that have a diverse range of affinities for the DA and 5-HT transporters. These compounds were used to explore the relationship between their biochemical properties and their reinforcing effects. Objectives: The objective was to assess the reinforcing efficacy of selected cocaine analogs and compare the results with their selectivity in binding to DA and 5-HT transporters. Methods: Rats were prepared with chronically indwelling intravenous cannulae and trained to self-administer cocaine on a progressive ratio (PR) schedule. A range of doses of seven cocaine analogs were substituted for cocaine in separate groups of animals. Results: The results demonstrate a wide range of reinforcing efficacies and potencies among the seven selected drugs. Four tropane analogs (WF-11, WF-23, WF-24, WF-55) were found to support self-administration behavior on a PR schedule while three did not (WF-31, WF-54 and WF-60). The DA/5-HT selectivity ratio was found to be a better predictor of self-administration behavior than affinity at the DA transporter alone. Conclusion: These data suggest that drugs with a higher affinity for the DA versus the 5-HT transporter are more likely to be self-administered. Received: 29 October 1998 / Final version: 5 February 1999  相似文献   
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