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971.

Background  

This study was designed to evaluate the possibility of avoiding small-for-size syndrome (SFSS) in living donor liver transplantation (LDLT) by increasing the donor’s body weight (BW) before liver donation.  相似文献   
972.
IntroductionErectile dysfunction (ED) is defined as the inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance. Although intuitively related, the link between erection hardness and erection maintenance has not been formally established and quantified.AimTo understand the components of erection maintenance through statistical modeling.MethodsData from a double-blind placebo-controlled trial of fixed-dose sildenafil (100 or 50 mg, 8 weeks) with open-label extension of flexible-dose sildenafil (100 and 50 mg, 4 weeks) were analyzed. Erection maintenance was assessed with item 4 (how often erection was maintained) or item 5 (difficulty in maintaining erection) of the International Index of Erectile Function (IIEF). Erection hardness was assessed with the Erection Hardness Score.Main Outcome MeasuresLongitudinal modeling estimated mean treatment differences averaged over the double-blind phase for sildenafil 100 mg vs. placebo and 50 mg vs. placebo. Statistical mediation analysis was applied to partition the effect of sildenafil (pooled into one treatment group) on erection maintenance directly and indirectly through erection hardness.ResultsLongitudinal mean differences for sildenafil 100 and 50 mg vs. placebo were high (P < 0.0001 for each), with large standardized effect sizes (>0.8). Mediation modeling showed that sildenafil treatment affected maintenance directly as well as indirectly via erection hardness, when measured by IIEF item 4 (direct effect, 44.6%; indirect effect, 55.4%) or IIEF item 5 (direct effect, 56.9%; indirect effect, 43.1%).ConclusionsSildenafil treatment significantly improved erection maintenance, a physiologic requirement for satisfactory sexual performance. According to our model, only approximately half of the effect of sildenafil on erection maintenance was estimated to be driven through direct effects. Rather, the effect of sildenafil on erection maintenance seems to be substantially driven by erection hardness. Therefore, achievement of optimal initial erection hardness appears to be an important treatment goal for enhancing erection maintenance and achieving successful ED treatment. Claes HIM, Goldstein I, Althof SE, Berner MM, Cappelleri JC, Bushmakin AG, Symonds T, and Schnetzler G. Understanding the effects of sildenafil treatment on erection maintenance and erection hardness.  相似文献   
973.
The effects of alcohol withdrawal on fibrinolysis were studied in 10 middle-aged male chronic alcoholics institutionalized for withdrawal therapy. All patients were sampled on admission [day 1 (D1)] and 21 days after alcohol withdrawal [day 22 (D22)]. The overall plasma fibrinolytic capacity (OFC) was assayed by measuring the ability of patient plasma to generate D-dimers from a standardized fibrin clot, and tissue-type plasminogen activator (t-PA) and t-PA inhibitor (PAI-1) levels were assayed together with serum cholesterol, triglyceride and cholesterol fractions. At D22, the OFC significantly increased in seven patients [D1 = 10 +/- 0.7 microg/h (mean +/- SD), D22 = 17 +/- 7.4 microg/h; P < 0.01], while t-PA and PAI-1 levels decreased in all patients but two (t-PA: D1 = 16.6 +/- 5 ng/ml, D22 = 10.2 +/- 3.8 ng/ml; P < 0.001; and PAI-1: D1 = 46 +/- 39 ng/ml, D22 = 21 +/- 28 ng/ml; P < 0.01). This study clearly demonstrates an increase in overall fibrinolytic activity after alcohol withdrawal, which is mainly due to a decrease in PAI-1 levels. These changes induced by alcohol abstinence might provide clear benefit by reducing the risk of thromboembolic events and particularly of stroke associated with elevated PAI-1 levels described in heavy drinkers.  相似文献   
974.
975.
Voltage-dependent anion channel (VDAC) is a mitochondrial porin also found in the neuronal membrane (pl-VDAC), where its function may be related to redox homeostasis and apoptosis. Murine models have evidenced pl-VDAC into caveolae in a complex with estrogen receptor alpha (mERα), which participates in neuroprotection against amyloid beta (Aβ), and whose integration into this hydrophobic domain remains unclear. Here, we have demonstrated in caveolae of human cortex and hippocampus the presence of pl-VDAC and mERα, in a complex with scaffolding caveolin-1 which likely provides mERα stability at the plasma membrane. In Alzheimer's disease (AD) brains, VDAC was accumulated in caveolae, and it was observed in dystrophic neurites of senile plaques, whereas ERα was expressed in astrocytes surrounding the plaques. Together with previous data in murine neurons demonstrating the participation of pl-VDAC in Aβ-induced neurotoxicity, these data suggest that the channel may be involved in membrane dysfunctioning observed in AD neuropathology.  相似文献   
976.
977.
The last decade has witnessed a growing interest in the neuropsychological study of bipolar disorder (BD). This chronic mood disorder is associated with persistent neurocognitive impairments even during periods of euthymia, particularly in the broad domains of attention, verbal memory and executive functions. More interestingly, cognitive dysfunction seems to predict a poorer functional outcome among BD patients and thus represents an important target for future therapies. The aetiology of cognitive dysfunction is probably multifactorial, including gene-environment interactions with potentially confounding variables as well. Drug-induced cognitive adverse effects represent an important and difficult to examine confounder. This review provides an overview of selected aspects of neurocognition in bipolar disorder with a focus on the relative contributions of medications as well as medical and psychiatric comorbid conditions to cognitive dysfunction. Finally, recommendations for future research in the field are provided including collaborative studies with larger samples, observational follow-up studies, as well as randomized clinical trials comparing head-to-head the neurocognitive impact of different medications.  相似文献   
978.
Magnetic resonance imaging of the kidney.   总被引:2,自引:0,他引:2  
High tissue contrast, multiplanar image capabilities, and tissue characterization render MR into an ideal imaging modality for effective evaluation of a wide range of renal disorders. It provides high details of anatomy and can suggest the composition of lesions. Improvements of MRI technology during the last years have made MRI increasingly attractive for body imaging. Fast imaging sequences and parallel imaging techniques have proved to be useful in minimizing artifacts from respiratory motion and magnetic susceptibility differences providing superior imaging quality. Additionally, the use of renally eliminated paramagnetic contrast agents permits assessment of parenchymal perfusion and visualization of the excretion of the contrast medium providing information on renal function.  相似文献   
979.
In this study we evaluated the endocrine, biochemical, and haematological derangements as well as pancreatic and histological changes of the bone-marrow in the primate following external fractionated subtotal marrow irradiation without bonemarrow reconstitution. The irradiation was administered in preparation for pancreatic transplantation. Two groups of animals (ten in each group) received 800 rad (8 Gy) and 1,000 rad (10 Gy) respectively over 4 to 5 weeks. A maximum of 200 rads (2 Gy) were administered weekly as photons from a 6 MV linear accelerator. During irradiation the animals remained normoglycaemic in the presence of transiently elevated liver enzymes and serum amylase values, which returned to normal on completion of the irradiation. Insulin release was significantly reduced in both groups during irradiation and was associated with minimally decreased K-values in the presence of mild glucose intolerance. Pancreatic light morphologic changes included structural changes of both exocrine and endocrine elements and included necrosis of the islet cells and acinar tissue. Islet histology demonstrated striking cytocavitary network changes of alpha and beta cells, including degranulation, vacuolization, mitochondrial destruction, and an increase in lysosomes. A hypoplastic bonemarrow ranging from moderate to severe was observed in all irradiated recipients. Near total fractionated body irradiation in the primate is therefore associated with elevated liver enzymes, pancytopenia, transient hyperamylasaemia, hypoinsulinaemia, a varying degree of pancreatitis, and bonemarrow hypoplasia.  相似文献   
980.
Studies were conducted to examine deficits in food intake regulation in MSG-treated rats that result from known or suspected damage to neurotransmitter systems involved in feeding. Male rats were injected with either MSG (4 mg/g) or sodium chloride on postnatal days 2 and 4 (MSG-Lo) or postnatal days 2, 4, 6 and 8 (MSG-Hi). As adults, MSG-treated and control rats (n = 12/group) were examined for deficits in pharmacologically elicited feeding and other measures of food intake regulation. A second group of MSG-treated (n = 9/group) and control rats (n = 12) were used to measure basal blood pressure and nociceptive reactivity in adulthood. Organ weights, body weight and neuropeptide Y (NPY) content in brain regions were determined at the end of the study. MSG-Hi rats consumed significantly less food than controls during the dark part of the light cycle. Both MSG-Hi and MSG-Lo groups ate significantly less food than controls after a 48-hour fast. MSG-Hi and MSG-Lo rats consumed significantly less food than controls in response to 1.0 mg/kg morphine. MSG-Hi rats consumed significantly less food than controls during the dark phase and significantly more food than controls during the light phase in response to naloxone (1.0 mg/kg). MSG-Lo ate significantly more than controls in response to 0.1 mg/kg guanfacine. MSG-Hi and MSG-Lo showed a significant attenuation in diazepam-stimulated feeding when compared to controls. Blood pressure was significantly lower in both MSG-Hi and MSG-Lo rats compared to controls. Tail flick latencies were not altered by MSG-treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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