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31.
Neurosurgical Review - The surgical injury of the intracranial portion of the facial nerve (FN) is a severe complication of many skull base procedures, and it represents a relevant issue in terms...  相似文献   
32.
Livers from donors after circulatory death (DCD) are a promising option to increase the donor pool, but their use is associated with higher complication rate and inferior graft survival. Normothermic machine perfusion (NMP) keeps the graft at 37°C, providing nutrients and oxygen supply. Human liver stem cell-derived extracellular vesicles (HLSC-EVs) are able to reduce liver injury and promote regeneration. We investigated the efficacy of a reconditioning strategy with HLSC-EVs in an experimental model of NMP. Following total hepatectomy, rat livers were divided into 4 groups: (i) healthy livers, (ii) warm ischemic livers (60 min of warm ischemia), (iii) warm ischemic livers treated with 5 × 108 HLSC-EVs/g-liver, and (iv) warm ischemic livers treated with a 25 × 108 HLSC-EVs/g-liver. NMP lasted 6 h and HLSC-EVs (Unicyte AG, Germany) were administered within the first 15 min. Compared to controls, HLSC-EV treatment significantly reduced transaminases release. Moreover, HLSC-EVs enhanced liver metabolism by promoting phosphate utilization and pH self-regulation. As compared to controls, the higher dose of HLSC-EV was associated with significantly higher bile production and lower intrahepatic resistance. Histologically, this group showed reduced necrosis and enhanced proliferation. In conclusion, HLSC-EV treatment during NMP was feasible and effective in reducing injury in a DCD model with prolonged warm ischemia.  相似文献   
33.
This paper investigates the relationship between social participation and subjective health. Using individual-level data from the British Household Panel Survey, we show that being an active member of a social or sport organisation increases self-rated physical and psychological health. For men, the benefits of social interaction work primarily via physical pathways, while women report a more psychosocial channel. We separate the main results by occupation and document some heterogeneity. Manual workers find more physical and psychological relief via social involvement, whereas non-manual workers are more likely to take relief from sport participation. Interestingly, as the number of associations in which the individual is active increases, the incremental increase in social benefits diminishes. Our findings point to the importance of promoting social and sport activities in health communication and policy making.  相似文献   
34.
Summary To investigate whether 5-HT1-like receptor-mediated inhibition of adenosine 3 : 5-cyclic monophosphate (cyclic AMP) accumulation occurs in nerves or smooth muscle of saphenous vein, infusions of 6-hydroxydopamine (6-OHDA) were administered to dogs with the aim of inducing sympathetic nerve damage. The effects of 6-OHDA on other 5-HT1-like receptor-mediated responses at the pre- and post-junctional level were investigated for comparison by studying 5-hydroxytryptamine (5-HT)-induced inhibition of 3H-noradrenaline release and contraction of smooth muscle respectively.Disruption of nerve function by 6-OHDA was revealed by the lack of catecholaminergic fluorescence and neurogenic contractile responses in saphenous veins from dogs treated with 6-OHDA. In addition, severe impairment of neuronal uptake mechanisms were apparent since basal efflux of 3H-noradrenaline, electrically-evoked release of 3H-noradrenaline and remaining 3H-noradrenaline content were considerably reduced. Some 3H-noradrenaline was taken up and released in 6-OHDA treated tissues which is consistent with the existence of nerve varicosities resistant to the present dosing regime of 6-OHDA, an observation substantiated by electron microscopy studies showing inconsistent lesions of nerve terminals.6-OHDA pre-treatment potentiated the smooth muscle contractile responses mediated by 5-HT1-like receptors as well as potentiating 5-HT-evoked inhibition of prostaglandin E2-stimulated cyclic AMP accumulation. It did not, however, affect 5-HT-induced inhibition of 3H-noradrenaline release. The present results suggest that inhibition of cyclic AMP accumulation by 5-HT occurs predominantly in smooth muscle. Correspondence to A. J. Kaumann at the above address  相似文献   
35.
Pregnancies in an 18-Year Follow-up after Biliopancreatic Diversion   总被引:4,自引:0,他引:4  
Background: 239 pregnancies occurred in 1136 women who had undergone biliopancreatic diversion (BPD). Methods: There were 73 abortions, and 14 pregnancies are presently in their course. The 152 term pregnancies (six twins) occurred in 129 women 2-173 months (mean 42.7) after BPD. Mean age and current excess weight were 31.4 years (20-42) and 29.1% (-6.9-78.2), and mean excess weight loss was 72.9% (30.4-110.5). Results: Mean weight gain during pregnancy was 6.2 kg (-21-25). In 32 patients (21%), parenteral nutritional support was needed. In all the other patients (79%), the usual supplementations were given. Of the newborns, 122 were delivered at term (84.7%) with a mean weight of 2842.4 g (1760-4600 g) and a mean length of 48.5 cm (43-59 cm), while the 22 preterm babies (15.3%) weighed 2151.1 g (1400-3850 g) and had a length of 44.6 cm (33-56 cm). Forty infants (27.8%) were small for gestational age but 17 of them weighed more than 2500 g. Eleven twins (one abortion at 26th week) were also delivered, with a mean weight of 2088.6 g (1200-3100 g) and a mean length of 45.6 cm (35-50 cm). Delivery was spontaneous in 85 instances (56%), while vacuum extractor was used in one, and 66 cesarean sections were performed. There were two birth malformations, one infant died after surgery for meconium obstruction and two died from unknown causes. Of the 129 women, 35 had been infertile before BPD. Conclusions: Disappearance of infertility and decrease of pregnancy risk are to be considered among the beneficial effects of weight reduction following BPD.  相似文献   
36.
A multifactorial etiology underlies the majority of cases of Alzheimer's disease (AD). Both ill-defined environmental and genetic factors contribute to the development of the disease. Allele epsilon 4 of ApoE is a genetic risk factor. Its presence increases the risk of developing AD. However, presence of e4 is neither necessary nor sufficient for the disease to arise. Apart from the common multifactorial forms of the disease, there are rare variants which are inherited as Mendelian traits. To date three genes are known that can be mutated in these rare forms of AD. Of these, mutations in the gene presenilin 1 on chromosome 14 are most frequent. In addition, mutations in the gene presenilin 2 on chromosome 1 and in the amyloid precursor protein gene (APP on chromosome 21) occur in autosomal dominant AD. This article reviews our present knowledge of the genetics of AD and discusses its relevance for patients with AD and their relatives.  相似文献   
37.
38.
The acute effects of cyclosporin (CsA, 20 mg(kg i.v.) and rapamycin (RAPA, 5 mg(kg i.v.) on glomerular dynamics were separately investigated by renal micropuncture in two groups of intact rats (group CsA and RAPA, respectively) and compared with vehicle-treated rats, used as controls (group CON). Left kidney glomerular filtration rate (GFR) was decreased by CSA (-35% vs. CON, P<0.05), but was not affected by RAPA (-14% vs. CON, NS), whereas the single-nephron GFR (SNGFR) was significantly decreased in both groups (-40% in CsA, P<0.01 and -26% in RAPA, P<0.05 vs. CON). In both groups glomerular plasma flow (GPF) was significantly reduced vs. CON (CsA: -48%, and RAPA: -25%) due to the increase in both afferent (Ra) and efferent (Re) glomerular resistances: group CSA showed a prevalent rise in Re (+98% vs. CON, P<0.001) than in Ra (+66%, P<0.001); in group RAPA the increment was modest and similar in Ra and Re (+33 and +32%, respectively, NS versus CON). A further group of rats was studied in which L-Arginine (ARG), the precursor of nitric oxide (NO), was administered (2.5 mg/Kg/min iv) with RAPA (group ARG). ARG limited the rise in Ra and Re, thereby preserving GPF; nevertheless, SNGFR remained low (-26% vs. CON, P<0.05) due to the decrease in the effective filtration pressure (-26% vs. CON). These data demonstrate that: (1) CsA is nephrotoxic at immunosuppressive doses; (2) RAPA, even at huge doses, has marginal effects on renal and glomerular dynamics; (3) the ARG-NO pathway is only partially involved in the vasoconstriction of superficial nephrons after RAPA administration.  相似文献   
39.
Prognostic value of CD40 in adult soft tissue sarcomas.   总被引:4,自引:0,他引:4  
PURPOSE: The purpose is to evaluate the expression of CD40, a membrane protein predominantly expressed on B cells, dendritic cells, and macrophages, in a series of adult soft tissue sarcomas and to test its possible prognostic value. EXPERIMENTAL DESIGN: CD40 expression was studied by immunohistochemistry. Correlations with other baseline characteristics of patients and tumors were analyzed with chi(2) test. The prognostic value was studied with univariable and multivariable analysis adjusted by age, sex, tumor size, grade, location, and distant metastases. RESULTS: Eighty-two patients, between January 1994 and May 2001, were analyzed. Membrane or cytoplasmic staining for CD40 protein was absent in 30% of the tumors but present in <10% of cells in 22 (27%), in 10% to 50% in 23 (28%), and in >50% of cells in 12 (15%) tumors. There was no correlation between CD40 expression and age, sex, size, grade, and location of the primary tumor and distant metastases. With 61 patients (74.4%) progressed and 31 (37.8%) dead, CD40 expression was a significant prognostic factor for disease-free and overall survival at univariable and multivariable analysis. Patients with tumors expressing CD40 in >50% of cells had a dramatically unfavorable prognosis with median disease-free and overall survival of 7 and 17 months, respectively, and hazard ratios of relapse and death as compared with patients with CD40-negative tumors of 2.89 (95% confidence interval: 1.26-6.60) and 6.92 (95% confidence interval: 2.18-22.0), respectively. CONCLUSIONS: These data suggest that expression of CD40 protein in >50% of cells might indicate an unfavorable prognosis in adult soft tissue sarcomas.  相似文献   
40.
BACKGROUND AND PURPOSE: Interstitial implants for brachytherapy boost in the breast conserving therapy of breast cancer can be performed in two ways; implants during the tumor excision (per-operative implants) or after the external beam therapy (delayed interstitial implants). Differences in cosmetic outcome were investigated. PATIENTS AND METHODS: Cosmetic results in 47 patients having a per-operative implant were compared to 123 patients having a delayed interstitial implant in a matched case-control study. Cosmesis was scored on a four-point-scale varying from 0 (excellent) to 3 (poor). RESULTS: After mean follow-up of 63 months, three observers found no difference in cosmetic outcome between the two groups after adjustment for variables found to be related with cosmesis (difference in mean score 0.50, P=0.26). Implant volume at 100% isodose was not found to differ (P=0.084) between the per-operative group (mean 102 cm3, S.D. 34 cm3) and the delayed group (mean 93 cm3, S.D. 29 cm3). CONCLUSIONS: Performing per-operative implants has not led to smaller implants. The method of performing brachytherapy does not result in marked differences in cosmetic outcome.  相似文献   
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