首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   170篇
  免费   5篇
儿科学   5篇
基础医学   10篇
临床医学   17篇
内科学   24篇
神经病学   57篇
特种医学   1篇
外科学   4篇
综合类   2篇
预防医学   14篇
眼科学   2篇
药学   37篇
肿瘤学   2篇
  2023年   2篇
  2022年   8篇
  2021年   6篇
  2020年   2篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   4篇
  2014年   6篇
  2013年   6篇
  2012年   6篇
  2011年   11篇
  2010年   7篇
  2009年   7篇
  2008年   14篇
  2007年   13篇
  2006年   8篇
  2005年   7篇
  2004年   10篇
  2003年   9篇
  2002年   10篇
  2001年   3篇
  2000年   3篇
  1999年   1篇
  1998年   4篇
  1997年   1篇
  1996年   1篇
  1995年   2篇
  1994年   2篇
  1992年   2篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1985年   1篇
  1984年   3篇
  1983年   1篇
  1979年   1篇
  1978年   1篇
  1977年   3篇
  1976年   1篇
  1972年   1篇
  1968年   1篇
排序方式: 共有175条查询结果,搜索用时 0 毫秒
21.
ObjectiveTo compare the diagnostic accuracy of transesophageal echocardiography (TEE) and cardiac computed tomography (CCT) in diagnosing infective endocarditis (IE).BackgroundTEE is a mainstay imaging modality for IE, while the use of CCT is becoming increasingly prevalent. Data directly comparing the diagnostic performance of these two imaging modalities for IE are limited.MethodsWe conducted a systematic review and meta-analysis of published literature in Embase, PubMed and Cochrane databases through October 1, 2020 for studies comparing diagnostic performance of CCT and TEE for the diagnosis of IE in the same patient populations. A meta-analysis of diagnostic accuracy was performed using the bivariate model based on studies that used surgical pathology as a reference standard for defining endocarditis. From a total of 10 studies included in the meta-analysis, a total of 872 patients were evaluated.ResultsThe pooled sensitivities and specificities of TEE for detecting vegetations were 96% and 83% respectively, whereas for CCT, they were 85% and 84%, respectively. In the prosthetic valve sub-group, the pooled sensitivities and specificities of TEE for detecting vegetations were 89% and 74% respectively, whereas for CCT, they were 78% and 94%, with CCT being more specific than TEE (p < 0.05). The pooled sensitivities and specificities of TEE for detecting periannular complications were 70% and 96% respectively, whereas for CCT, they were 88% and 93%, respectively. CCT showed a trend (p = 0.06) towards higher sensitivity than TEE for detection of periannular complications. The pooled sensitivities and specificities of TEE for detecting leaflet perforation were 79% and 93% respectively, whereas for CCT, they were 48% and 93% respectively, with TEE being more sensitive (p < 0.05). The two modalities also showed comparable diagnostic performance for detecting fistulae, paravalvular leaks and prosthetic valve dehiscence.ConclusionIn a contemporary comparative meta-analysis, TEE and CCT demonstrated both good diagnostic accuracy for detecting valvular involvement and complications of IE. TEE performed better for detecting leaflet defects, whereas CCT performed better in cases of prosthetic valve involvement, and showed a trend towards improved detection of periannular complications. Appropriate, complementary use of both TEE and CCT in a multimodality imaging approach in clinical practice may achieve the highest diagnostic performance.  相似文献   
22.
23.
1. 1. Free inositol levels in occipital and parietal cortex of Alzheimer's Disease (AD) patients were reported to be significantly elevated by 10–35% compared with matched controls, studied by magnetic resonance spectroscopy (MRS) during life.
2. 2. An MRS study of post mortem samples failed to demonstrate a significant difference between AD and controls.
3. 3. The present study shows non-significant trends of 13% increase in frontal cortex and 5% and 21% decrease in occipital cortex and cerebellum respectively, in post mortem brain specimens of AD patients measured gas chromatographically (GC).
  相似文献   
24.
Summary CSF inositol was reported to be reduced in depression and inositol has been reported to be effective in treatment of depression. We studied CSF inositol in 18 drug-free depressed patients and 36 normal controls; the depressed patients then participated in an open trial of 18 gm daily inositol treatment for 4 weeks. There was no difference in pre-treatment CSF inositol between depressed patients and controls. CSF inositol levels did not predict response on the Hamilton Depression Scale to 4 weeks of inositol treatment.  相似文献   
25.
Plasma inositol levels of lithium-treated manic-depressives (LTMD), schizophrenics and healthy volunteers have been studied. In contrast with the findings of Allison and Stewart, that Li treatment raises rat plasma inositol while lowering brain inositol, but in agreement with a previous report of our group of no effect of lithium on CSF inositol levels, we now show no significant difference in plasma inositol concentrations of LTMD as compared with those of control subjects. Plasma inositol levels of the schizophrenics in the present study are slightly but significantly decreased from those of controls.  相似文献   
26.

Background  

Contaminated environmental surfaces may play an important role in transmission of some healthcare-associated pathogens. In this study, we assessed the adequacy of cleaning practices in rooms of patients with Clostridium difficile-associated diarrhea (CDAD) and vancomycin-resistant Enterococcus (VRE) colonization or infection and examined whether an intervention would result in improved decontamination of surfaces.  相似文献   
27.
Glycogen synthase kinase (GSK)-3beta, a serine/threonine kinase highly abundant in brain is a negative regulator of signal transduction cascades including the phosphatidylinositol-3-kinase (PI3-K)/Akt and the Wnt. GSK-3beta has recently been suggested to be an intracellular target of the mood stabilizers lithium and valproate and of the typical and atypical antipsychotic agents haloperidol and clozapine. We have previously shown that these agents do not alter frontal cortex GSK-3beta protein levels or activity. The current study was conducted to assess the effect of psychotropic drugs on phospho-Ser9-GSK-3beta levels in rodents. Chronic administration of haloperidol to rats resulted in a significant reduction in frontal cortex phospho-Ser9-GSK-3beta protein levels and no change in those of GSK-3alpha, while chronic administration of clozapine or subchronic administration of valproate caused significant elevation of GSK-3beta protein levels. Mice treated chronically with lithium exhibited the most prominent elevation in phospho-Ser9-GSK-3beta. The results support the notion that GSK-3beta may be a common target for mood stabilizers and neuroleptics.  相似文献   
28.
Vincristine is considered as a backbone of therapy in the induction and consolidation phases of pediatric malignancies. Neurotoxicity is a principal side effect of its use. This study is a randomized single-blinded placebo-controlled clinical trial to evaluate the role of glutamic acid in ameliorating neurotoxicity in pediatric patients with hematologic and solid tumors receiving vincristine during induction course. Fifty-four patients in the glutamic acid group received glutamic acid 1.5 grams daily orally in 3 divided doses during the 4-week induction with vincristine in a dose of 1.5 mg/m2 IV weekly. Placebo group (40 patients) received oral placebo 3 times daily in the same way as the glutamic acid group. The onset of neurotoxicity was significantly earlier in placebo group than in glutamic acid group regarding tendon Achilles reflex, Patellar reflex, parasthesia, and increased frequency of constipation. This was statistically significant mostly in third and fourth visits, no severe cases of strength and mental alteration side effects in both groups. Glutamic acid was well tolerated with no gastrointestinal side effects in patients. This study suggests that the coadministration of oral glutamic acid with repetitive intravenous bolus injections of vincristine resulted in a reduction of its neurotoxicity.  相似文献   
29.
HIV has classically been a wasting disease. However, in the United States, obesity is increasingly common among HIV-infected individuals receiving effective antiviral treatment. The risks of obesity are unclear in HIV, although the increased prevalence of diabetes and cardiovascular disease in the presence or absence of obesity causes growing concern. This study aimed to assess the effects of weight loss (through energy restriction combined with aerobic and resistance exercise) on body composition, body fat distribution, resting energy expenditure, quality of life (QOL), strength and fitness, and metabolic risk factors in obese, HIV-infected women. Eighteen HIV-infected women with a body mass index of 30 or more completed a 12-week weight loss program. Before and after the intervention, body composition and fat distribution by dual energy x-ray absorptiometry and whole-body magnetic resonance imaging, resting energy expenditure by indirect calorimetry, QOL, strength, and fitness were measured. Insulin sensitivity by intravenous glucose tolerance test and circulating cardiovascular risk factors (including lipids, tissue plasminogen activator, and plasminogen activator inhibitor 1) were measured in a subset (n = 9). Daily food intake and total body weight decreased (mean ± SD) by 3195 ± 477 kJ and 6.7 ± 4.2 kg, respectively. Weight lost was 95.5% fat by dual energy x-ray absorptiometry or 6.2 L of subcutaneous adipose tissue, 0.7 L visceral adipose tissue, and 0.8 L skeletal muscle by magnetic resonance imaging. Resting energy expenditure fell approximately 419 kJ, strength and fitness increased by 28.9% ± 18.5% and 36.8% ± 41.6%, respectively, and QOL improved in 11 of 13 dimensions. There was significant insulin resistance in the subset with metabolic measurements at baseline, and at follow-up there was no improvement in fasting glucose, insulin, or insulin sensitivity, nor was there any change in fasting lipids, tissue plasminogen activator, or plasminogen activator inhibitor 1. There was no significant change in CD4 count or HIV viral load. In conclusion, moderate weight loss achieved by a short-term program of diet and exercise in obese HIV-positive women appears safe and induces loss of adiposity in both the subcutaneous adipose tissue and visceral adipose tissue regions. Despite reduced food intake, weight and fat loss, as well as improvements in strength, fitness, and QOL, the lack of improvement in metabolic parameters suggests that additional interventions may be necessary to reduce the risk of diabetes and cardiovascular disease in this population.  相似文献   
30.

Rationale

Lithium has been a standard pharmacological treatment for bipolar disorder over the last 60 years; however, the molecular targets through which lithium exerts its therapeutic effects are still not defined. Attenuation of the phosphatidylinositol signal transduction pathway as a consequence of inhibition of inositol monophosphatase (IMPase) has been proposed as one of the possible mechanisms for lithium-induced mood stabilization.

Objectives

The objective was to study the behavioral effect of the specific competitive IMPase inhibitor L-690,330 in mice in the lithium-sensitive pilocarpine-induced seizures paradigm and the forced swim test (FST).

Methods

The inhibitor was administered intracerebroventricularly in liposomes.

Results

L-690,330 increased the sensitivity to subconvulsive doses of pilocarpine and decreased immobility time in the FST.

Conclusions

It is possible that the behavioral effects of lithium in the pilocarpine-induced seizures and in the FST are mediated through the inhibition of IMPase, but reversal of the inhibitor’s effect with intracerebroventricular inositol would be an important further step in proof.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号