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21.
OBJECTIVE: To report the occurrence of a transient ischemic attack (TIA) temporally related to the initiation of paroxetine. CASE SUMMARY: A 57-year-old white man with a history of intermittent atrial fibrillation and hypercholesterolemia developed slurred speech and a facial droop 3 days after starting paroxetine. He was diagnosed with a TIA, hospitalized, and given anticoagulation treatment. The presenting symptoms resolved, but recurred when paroxetine was restarted 2 days later. DISCUSSION: Platelets secrete serotonin, which mediates vasoconstriction through stimulation of 5-HT2a receptors. This is counterbalanced by the release of the vasodilator nitric oxide upon serotonin stimulation of endothelial 5-HT1 receptors. In conditions such as atherosclerosis, the damage to the endothelium leads to a greater vasoconstrictive response. Paroxetine has been reported to weakly inhibit norepinephrine reuptake and nitric oxide production in addition to increasing serotonergic activity, potentially compounding the vasoconstrictive response. An objective causality assessment revealed that the TIA was probably an adverse event resulting from use of paroxetine. CONCLUSIONS: Use of paroxetine and other selective serotonin-reuptake inhibitors may result in changes of the vasculature and subsequent ischemic events in predisposed patients.  相似文献   
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OBJECTIVE: The purpose of this study was to examine the efficacy of psychostimulant medication in a naturalistic sample of preschoolers. Benefits and side effects for methylphenidate and mixed amphetamine salts (Adderall) were examined. METHOD: Twenty-eight preschoolers (ages 4.0 - 5.9) participated in the present investigation. They were obtained consecutively from a large sample of suburban children assessed for attention-deficit/hyperactivity disorder. After having received various dosing levels of a stimulant in a placebo-controlled crossover design, best dose was assigned based on the lowest Abbreviated Symptoms Questionnaire T score received in a given week. All analyses compared best dose ratings to placebo ratings. RESULTS: Preschoolers' behavioral ratings by parents and teachers were improved as a function of stimulant medication. More than 82% of the medicated sample improved their behavioral rating by at least 1 SD as demonstrated by receiver operating characteristic (ROC) analyses, with more than 50% of medicated preschoolers improving by more than 2 SD. Side effects were infrequent at best dose of medication. CONCLUSIONS: Clinically significant changes in behavioral ratings of preschoolers were noted in response to stimulant medication. Both stimulants were well tolerated. ROC curves were useful for clearly depicting on a case-by-case basis how much improvement was derived from psychopharmacological treatment.  相似文献   
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We are reporting a series of eight patients ranging in age from 3 to 10 years who sustained plantar-flexion injuries of the foot, resulting in injuries to the tarsometatarsal (TMT) interval. All injuries were identified within 3 days and treated with molded short leg immobilization. We evaluated all patients an average of 32 months after injury with physical examination and the Midfoot Functional Rating (MFR) score. Seven patients had no limitations in their activities of daily living or athletic endeavors. These seven patients had MFR scores of 100. One patient had complaints of midfoot pain with running for >5 min and radiographic evidence of degenerative changes across the TMT interval at 3-year follow-up. These results suggest that although indirect pediatric TMT injuries have a generally favorable prognosis, early degenerative changes can occur and may be responsible for chronic pain and activity limitation. Degenerative changes in this weight-bearing region in a young patient can have lifelong implications. Patients and parents may benefit from discussion of the potential for future midfoot compromise following this injury.  相似文献   
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OBJECTIVE: Although obstructive sleep apnoea syndrome (OSAS) is accompanied by an increased atherosclerotic cardiovascular disease burden, its relationship with arterial stiffness is not yet well determined. We investigated whether essential hypertensive individuals with OSAS are characterized by increased arterial stiffness. METHODS: Our study population consisted of 46 consecutive patients with newly diagnosed untreated stage I-II essential hypertension suffering from OSAS (35 men, aged 49 +/- 8 years) and 53 hypertensive individuals without OSAS, matched for age, sex, and smoking status. All subjects underwent polysomnography, echocardiography and aortic stiffness evaluation by means of carotid-femoral pulse wave velocity (c-fPWV) measurements. RESULTS: Hypertensive subjects with OSAS [apnoea/hypopnoea index (AHI)>or =5] compared with hypertensive subjects without OSAS (AHI < 5) demonstrated increased levels of body mass index (31.4 +/- 4 versus 29.3 +/- 4 kg/m2, P = 0.015), office systolic/diastolic blood pressure (151/99 versus 145/94 mmHg, respectively, P < 0.05, for both cases) and relative wall thickness (RWT; 0.46 +/- 0.06 versus 0.42 +/- 0.07, P=0.010). Hypertensive subjects with OSAS compared with those without OSAS had significantly increased c-fPWV by 9% (8.56 +/- 0.49 versus 7.85 +/- 0.93 m/s, P=0.001) and this difference remained significant even after adjustment for confounders (P=0.04). In the total study population, c-fPWV was correlated with age (r=0.35, P=0.015), office systolic blood pressure (r=0.30, P=0.007), RWT (r=0.30, P=0.03), logAHI (r=0.389, P=0.0001) and minimum oxygen saturation (r=-0.418, P=0.0001). CONCLUSIONS: OSAS has a significant incremental effect on aortic stiffening in the setting of middle-aged essential hypertensive subjects. This finding suggests that the presence of OSAS in a hypertensive patient accelerates vascular damage, increasing cardiovascular risk.  相似文献   
27.
Although hepatitis C virus (HCV) infection has been shown to be associated with development of non-Hodgkin's lymphoma (NHL), few studies have investigated the association between chronic HBV infection and NHL. The purpose of this study was to compare the incidence of NHL between patients with and without chronic hepatitis B virus (HBV) infection. Using automated laboratory result and clinical data from two United States health systems, we identified individuals with chronic HBV infection from January 1, 1995 through December 31, 2001. Using each health system's population-based tumor registry, we identified all cases of NHL diagnosed through December 31, 2002. We excluded any individual with a history of NHL or human immunodeficiency virus (HIV). We fit Cox proportional hazards models to calculate hazard ratios comparing the incidence of NHL between chronic HBV-infected patients (N = 3,888) and patients without HBV (N = 205,203) drawn from the source populations. We identified 8 NHL cases in the chronic HBV infection cohort and 111 cases in the comparison cohort. Patients with chronic HBV infection were 2.8 times more likely to develop NHL than matched comparison patients (adjusted hazard ratio = 2.80, 95% confidence interval = 1.16-6.75), after controlling for age, race, sex, income, Charlson comorbidity index, study site, and HCV infection. CONCLUSION: chronic HBV-infected patients were nearly 3 times more likely to develop NHL than comparison patients.  相似文献   
28.
Pulmonary hemorrhage is a relatively common complication of blunt chest trauma. Occasionally, it may result from pulmonary barotrauma after scuba diving or from sports activities not associated with barotrauma such as long breath-hold diving. We report a case of symmetric diffuse upper lobe hemorrhage resulting from a bungee jump in a previously healthy man. Bungee jumping is an increasingly popular sport with relatively few reported injuries. To our knowledge pulmonary hemorrhage in this setting has not yet been described.  相似文献   
29.
RATIONALE AND OBJECTIVES: The capability of wavelet transforms to separate signals into frequency bands is the basis for its use in image compression and storage, data management and transmission, and, recently, extraction of latent images of tissue components from noisy medical images. Analysis of temporal variations of radiofrequency backscatter of intravascular ultrasound with one-dimensional wavelets can detect lipid-laden plaque in coronary arteries with a sensitivity and specificity of >80%. In this study we evaluate the capability of a novel, 3-dimensional isotropic wavelet analysis to perform high resolution, non-directionally biased, statistically reliable, non-invasive discrimination between components of human coronary atherosclerotic plaques in micro-CT. MATERIALS AND METHODS: Coronary artery segments (5-15 mm) were excised at necropsy from 18 individuals with advanced coronary atherosclerosis. Specimens were imaged using a GE Locus SP ex vivo micro-CT scanner and processed for histological correlation (833 sections). The isotropic wavelet constructs were applied to the entire volume of CT data of each arterial segment to distinguish tissue textures of varying scales and intensities. Voxels were classified and plaque characterization achieved by comparing the relative magnitudes of these wavelet constituents to that of several reference plaque tissue components. RESULTS: Processing of micro-CT images via these isotropic wavelet algorithms permitted 3-D, color-coded, high resolution, digital discrimination between lumen, calcific deposits, lipid-rich deposits, and fibromuscular tissue providing detail not possible with conventional thresholding based on Hounsfield intensity units. Using the isotropic wavelets (with histology as the gold standard), lipid-rich pools approaching the size of the filter for the isotropic wavelet algorithm (0.25 mm [250 microns] in length) were identified with 81% sensitivity and 86% specificity. Calcific deposits, fibromuscular tissue, and lumen equal to or larger than the wavelet filter size were detected without error (100% sensitivity and specificity). CONCLUSION: Isotropic wavelet analysis permits high resolution, multi-dimensional identification of coronary atherosclerotic plaque components in micro-CT with sensitivity and specificity similar to that achieved with data obtained invasively (from IVUS in vivo) using one-dimensional wavelets. Further studies are necessary to test the applicability of this technology to clinical, multi-detector scanners.  相似文献   
30.
Microvascular endothelial cells express a variety of cell-surface integrins in vivo and in vitro with varying affinities for matrix proteins. The vitronectin receptor (VnR), a complex of the alpha v and beta 3 integrin chains, is capable of binding to a variety of matrix proteins that are deposited in injured tissues, including vitronectin, fibrinogen, and thrombin. Staining of frozen sections of human skin with antibodies recognizing the VnR and examination by immunofluorescence microscopy demonstrates staining in a vascular pattern suggesting in vivo expression of the vitronectin receptor on endothelial cells. Examination of pure cultures of human dermal microvascular endothelial cells (HDMEC) by flow-cytometric analysis and enzyme-linked immunosorbent assay confirmed that HDMEC also express cell surface VnR complex in vitro. Stimulation of human dermal microvascular endothelial cells in vitro with agents that stimulate protein kinase C resulted in dose- and time-dependent increases in expression of alpha v and beta 3 integrin chains. Additionally, stimulation with basic fibroblast growth factor induced similar increases, but stimulation with transforming growth factor-beta or interleukin-1 alpha failed to increase VnR expression. Increases in cell-surface VnR expression also correlated with an increased ability of microvascular endothelial cells to bind to vitronectin, but not fibronectin-coated surfaces. Although increases in cell-surface expression of beta 3 paralleled increases in expression of cell-surface alpha v, regulation of mRNA expression was distinct for each chain. These data suggests that microvascular endothelial cells express the VnR complex in vivo, that the cell-surface expression of this integrin on dermal microvascular endothelial cells can be regulated, and that this regulation may be important in cell adherence, cell migration, and wound healing.  相似文献   
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