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11.
The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%);  相似文献   
12.
李峰生  杨曌  江其生 《免疫学杂志》2005,21(Z1):103-105
机体受到一定剂量核辐射后会出现多个器官结构和功能的改变.本文综述了机体受到低剂量核辐射后出现的免疫细胞数量和功能变化,包括淋巴细胞总数和部分亚群数量、淋巴细胞转化率、血清免疫球蛋白含量以及单核细胞功能等变化.同时还综述了核辐射对内分泌及遗传的影响.  相似文献   
13.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
14.
A model of corrective gene transfer in X-linked ichthyosis   总被引:5,自引:0,他引:5  
Single gene recessive genetic skin disorders offer attractive prototypes for the development of therapeutic cutaneous gene delivery. We have utilized X-linked ichthyosis (XLI), characterized by loss of function of the steroid sulfatase arylsulfatase C (STS), to develop a model of corrective gene delivery to human skin in vivo. A new retroviral expression vector was produced and utilized to effect STS gene transfer to primary keratinocytes from XLI patients. Transduction was associated with restoration of full-length STS protein expression as well as steroid sulfatase enzymatic activity in proportion to the number of proviral integrations in XLI cells. Transduced and uncorrected XLI keratinocytes, along with normal controls, were then grafted onto immunodeficient mice to regenerate full thickness human epidermis. Unmodified XLI keratinocytes regenerated a hyperkeratotic epidermis lacking STS expression with defective skin barrier function, effectively recapitulating the human disease in vivo. Transduced XLI keratinocytes from the same patients, however, regenerated epidermis histologically indistinguishable from that formed by keratinocytes from patients with normal skin. Transduced XLI epidermis demonstrated STS expression in vivo by immunostaining as well as a normalization of histologic appearance at 5 weeks post-grafting. In addition, transduced XLI epidermis demonstrated a return of barrier function parameters to normal. These findings demonstrate corrective gene delivery in human XLI patient skin tissue at both molecular and functional levels and provide a model of human cutaneous gene therapy.   相似文献   
15.
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view.  相似文献   
16.
Internet网上细胞凋亡研究的信息资源及其利用   总被引:1,自引:0,他引:1  
杨连君  王文亮 《医学争鸣》2000,21(11):229-230
0 引言  Internet网上含有丰富的信息资源 ,科研人员可以通过 Internet网了解其所研究领域的最新发展动态 ,获取全面和系统的科研信息 ,有利于进行学术交流[1 ] .然而网上信息浩如烟海 ,当检索某一专门领域的资料时 ,有时无从下手 .我们在科研实践中对 Internet网上主要的细胞凋亡研究信息资源及其查找方法进行了归纳 .1 细胞凋亡专业网站1. 1  The Cell death society (http:/ / www.celldeath-apoptosis.org) 为美国细胞死亡学会主办 ,概括了细胞凋亡和程序性细胞死亡研究的各个领域 ,包括与细胞凋亡有关的各种疾病 .可以免费注册…  相似文献   
17.
18.
In impaction grafting of contained bone defects after revision joint arthroplasty the graft behaves as a friable aggregate and its resistance to complex forces depends on grading, normal load and compaction. Bone mills in current use produce a distribution of particle sizes more uniform than is desirable for maximising resistance to shear stresses. We have performed experiments in vitro using morsellised allograft bone from the femoral head which have shown that its mechanical properties improve with increasing normal load and with increasing shear strains (strain hardening). The mechanical strength also increases with increasing compaction energy, and with the addition of bioglass particles to make good the deficiency in small and very small fragments. Donor femoral heads may be milled while frozen without affecting the profile of the particle size. Osteoporotic femoral heads provide a similar grading of sizes, although fewer particles are obtained from each specimen. Our findings have implications for current practice and for the future development of materials and techniques.  相似文献   
19.
OBJECTIVE: To determine the validity of a clinical diagnosis of probable or possible dementia with Lewy bodies (DLB) made using International Consensus criteria. BACKGROUND: Validation studies based on retrospective chart reviews of autopsy-confirmed cases have suggested that diagnostic specificity for DLB is acceptable but case detection rates as low as 0.22 have been suggested. METHODS: We evaluated the first 50 cases reaching neuropathologic autopsy in a cohort to which Consensus clinical diagnostic criteria for DLB, National Institute for Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for AD, and National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences criteria for vascular dementia (VaD) had been prospectively applied. RESULTS: Twenty-six clinical diagnoses of DLB, 19 of AD, and 5 of VaD were made. At autopsy, 29 DLB cases, 15 AD, 5 VaD, and 1 progressive supranuclear palsy were identified. The sensitivity and specificity of a clinical diagnosis of probable DLB in this sample were 0.83 and 0.95. Of the five cases receiving a false-negative diagnosis of DLB, significant fluctuation was present in four but visual hallucinations and spontaneous motor features of parkinsonism were generally absent. Thirty-one percent of the DLB cases had additional vascular pathology and in two cases this contributed to a misdiagnosis of VaD. No correlations were found between the distribution of Lewy bodies and clinical features. CONCLUSION: The Consensus criteria for DLB performed as well in this prospective study as those for AD and VaD, with a diagnostic sensitivity substantially higher than that reported by previous retrospective studies. DLB occurs in the absence of extrapyramidal features and in the presence of comorbid cerebrovascular disease. Fluctuation is an important diagnostic indicator, reliable measures of which need to be developed further.  相似文献   
20.
BACKGROUND: Fibreoptic bronchoscopy (FOB) is the usual initial investigation of choice in patients with suspected endobronchial carcinoma, but it is often non-diagnostic. Once a positive diagnosis has been made, many patients undergo staging by computed tomographic (CT) scanning to assess the extent of the disease and its suitability for radical treatment. To determine whether initial CT scanning before FOB is a cost effective way of reducing subsequent unnecessary or unhelpful invasive diagnostic procedures, a study was undertaken in 171 patients with suspected endobronchial carcinoma. METHODS: A randomised two group study was performed with all patients undergoing an initial CT staging scan. In group A the CT scans were reviewed before FOB, allowing cancellation or a change to an alternative invasive procedure if considered appropriate. In group B all patients proceeded to FOB with the bronchoscopist blinded to the result of the CT scan until after the procedure. RESULTS: In group A six of 90 patients (7%) required no further investigations as the CT scan was either normal, consistent with benign disease, or consistent with widespread metastatic disease. Of the remainder, bronchoscopy was diagnostic in 50 of 68 (73%) in group A compared with 44 of 81 (54%) in group B (p = 0.015). Overall, a positive diagnosis was made after a single invasive investigation in 64 of 84 patients (76%) in group A compared with only 45 of 81 patients (55%) in group B (p = 0.005). Only seven of 90 patients (8%) in group A required more than one invasive investigation compared with 15 of 81 patients (18.5%) in group B. In patients with malignancy, bronchoscopy was more likely to be diagnostic in group A (50 of 56 patients (89%)) than in group B (44 of 62 (71%); p = 0. 012), and the diagnosis was more frequently made on the initial invasive investigation (group A, 63 of 70 (90%); group B, 44 of 62 (71%); p = 0.004). Because of the lower number of invasive procedures performed in group A than in group B, the cost of performing CT scans before FOB in all patients in group A would have equated to a projected cost of performing CT scans in 60% of patients after FOB in group B. CONCLUSIONS: Performing initial CT thoracic scans before bronchoscopy in patients with suspected endobronchial malignancy is a cost effective way of improving diagnostic yield from invasive diagnostic procedures and occasionally may obviate the need for any further investigation.  相似文献   
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