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CONTEXT: Hormone therapy increases the risk of venous thromboembolism (VTE) among postmenopausal women. This effect may be modulated by the expression of cytochromes P450 3A5 (CYP3A5) and 1A2 (CYP1A2) which are involved in the hepatic metabolism of estrogens. OBJECTIVE: The objective was to investigate the impact of CYP3A5 and CYP1A2 genetic polymorphisms on the association of VTE with hormone therapy. DESIGN: We conducted a case-control study. SETTING: This study was conducted in eight French hospital centers and in the general population. PATIENTS: CYP3A5 and CYP1A2 genotypes were evaluated among 195 cases with a first documented episode of idiopathic VTE and 533 controls matched for center, age, and admission date. OUTCOME MEASURE: The outcome measure was hormone therapy by route of estrogen administration. RESULTS: Overall, oral but not transdermal estrogen increased VTE risk [odds ratio (OR) = 4.5, 95% confidence interval (CI) = 2.6-7.6, and OR = 1.2, 95% CI = 0.8-1.8, respectively]. The allele frequency of CYP3A5*1 was 9 and 10% among cases and controls (OR = 1.0; 95% CI = 0.6-1.5) and that of CYP1A2*1F was 72 and 71% among cases and controls (OR = 1.5; 95% CI = 0.8-2.8). Compared with nonusers, OR for VTE in users of oral estrogen was 3.8 (95% CI = 2.1-6.7) among patients without CYP3A5*1 allele and 30.0 (95% CI = 4.4-202.9) among patients with this allele (test for interaction P = 0.04). By contrast, there was no significant interaction between CYP3A5*1 allele and transdermal estrogen on VTE risk. There is no interaction between CYP1A2 genetic polymorphism and hormone therapy on VTE risk. CONCLUSIONS: Women with CYP3A5*1 allele using oral estrogen can define a subgroup at high VTE risk. Additional data are needed to assess the relevance of this genetic biomarker in the medical management of menopause.  相似文献   
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Objectives To report the feasibility and results of diagnostic hysteroscopy in women at risk of HNPCC. Methods Fifty-seven women with mismatch repair gene mutations (n = 11) or Amsterdam II criteria (n = 46) were followed-up prospectively from January 1999 to March 2005. Flexible hysteroscopy was performed once a year. The endometrium was sampled routinely. Results Of 91 attempted hysteroscopies, 10 failed. The endometrial mucosa appeared normal in 34 cases. Polyps were seen in 12 cases, atrophy in 11, hypertrophy in 10, and fibroids in 7; two hysteroscopies suspected malignancy. A micropolypoid appearance was visualized during five hysteroscopies (5/81, 6%). Of the 86 endometrial biopsy attempts, 64 were successful and showed atrophy (n = 14), proliferation (n = 12), secretion (n = 27), polyps (n = 6), simple hyperplasia without atypia (n = 3), or cancer (n = 2). Micropolypoid appearance was not associated with a specific histological pattern. Operative hysteroscopy was done in 24 cases; in two patients with apparently benign focal lesions the results showed simple hyperplasia without atypias. Five patients underwent hysterectomy (simple hyperplasia without atypias, n = 2; endometrioid adenocarcinoma, n = 2; or secretory mucosa, n = 1). This study led to diagnosis of endometrial simple hyperplasia in 6% of cases and of cancer in 3%. Conclusions In patients at risk of HNPCC, hysteroscopy appears feasible to screen endometrial pathology. Two cancers have been diagnosed over 91 patient-years at risk. Hysteroscopy should be compared to sonography as a screening tool in women at risk of HNPCC.  相似文献   
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Background  Behcet's disease (BD) is a chronic, inflammatory, multisystem vasculitic disorder. There is no reliable laboratory marker that indicates disease activity. Neopterin is an immunological marker of cellular immune activation, which is secreted by monocytes/macrophages as a result of interferon-gamma (IFN-γ) secretion by activated T lymphocytes.
Objective  We aimed to investigate serum and urine neopterin levels in BD patients.
Methods  Forty-five patients who were diagnosed according to the criteria of the International Study Group for BD and 45 age- and sex-matched healthy controls were enrolled in the study. Disease activity was considered by clinical findings. Serum and urine neopterin levels and serum IFN-γ levels were measured.
Results  The mean values of serum and urine neopterin levels were 12.68 ± 4.87 nmol/L and 167.53 ± 148.73 µmol/mol creatinine, respectively, in BD patients ( P =  0.000 and P  = 0.008, respectively), which were statistically significantly different from the control group. However, there was no significant statistical difference between serum and urine neopterin levels of the clinically active and inactive patients. It was also found that the mean value of serum IFN-γ levels was higher in healthy controls than in BD patients ( P =  0.000).
Conclusions  We conclude that serum and urinary neopterin measurement can not be used as a reliable laboratory marker as the BD patients' serum and urinary neopterin levels do not increase in the active stage even though these levels increase when compared to healthy controls.  相似文献   
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余晓林  程鹏远  刘红  陈万平  朱华锋 《医学争鸣》2005,26(18):1720-1721
目的:研究慢性肝炎患者HBV-DNA水平与病情变化的关系. 方法:采用荧光标记定量PCR的方法,测定慢性乙型肝炎急性发作患者(HBeAg阳性45例,抗HBe阳性30例)其活动期和恢复期的血清HBV-DNA含量. 结果:HBeAg阳性组血清HBV-DNA含量(Logarrithm copy/mL)在活动期显著高于恢复期[(10.2±1.6) vs (5.3±2.1), P<0.05],抗-HBe阳性组血清HBV-DNA含量(Logarrithm copy/mL)在活动期显著高于恢复期[(7.6±1.3) vs (4.0±2.0), P<0.05]. 另外,活动期血清HBV-DNA含量(Logarrithm copy/mL)在HBeAg阳性组显著高于抗HBe阳性组[(10.2±1.6) vs (7.6±1.3), P<0.05]. 血清HBV-DNA水平与丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)及总胆红素(T-BLLI)之间无相关性. 结论:HBV-DNA复制水平与慢性乙型病毒性肝炎的活动密切相关.  相似文献   
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Quantitative evaluation of brain MRI/SPECT fusion methods for normal and in particular pathological datasets is difficult, due to the frequent lack of relevant ground truth. We propose a methodology to generate MRI and SPECT datasets dedicated to the evaluation of MRI/SPECT fusion methods and illustrate the method when dealing with ictal SPECT. The method consists in generating normal or pathological SPECT data perfectly aligned with a high-resolution 3D T1-weighted MRI using realistic Monte Carlo simulations that closely reproduce the response of a SPECT imaging system. Anatomical input data for the SPECT simulations are obtained from this 3D T1-weighted MRI, while functional input data result from an inter-individual analysis of anatomically standardized SPECT data. The method makes it possible to control the 'brain perfusion' function by proposing a theoretical model of brain perfusion from measurements performed on real SPECT images. Our method provides an absolute gold standard for assessing MRI/SPECT registration method accuracy since, by construction, the SPECT data are perfectly registered with the MRI data. The proposed methodology has been applied to create a theoretical model of normal brain perfusion and ictal brain perfusion characteristic of mesial temporal lobe epilepsy. To approach realistic and unbiased perfusion models, real SPECT data were corrected for uniform attenuation, scatter and partial volume effect. An anatomic standardization was used to account for anatomic variability between subjects. Realistic simulations of normal and ictal SPECT deduced from these perfusion models are presented. The comparison of real and simulated SPECT images showed relative differences in regional activity concentration of less than 20% in most anatomical structures, for both normal and ictal data, suggesting realistic models of perfusion distributions for evaluation purposes. Inter-hemispheric asymmetry coefficients measured on simulated data were found within the range of asymmetry coefficients measured on corresponding real data. The features of the proposed approach are compared with those of other methods previously described to obtain datasets appropriate for the assessment of fusion methods.  相似文献   
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Reflex epileptic seizures of opercular origin have been described previously based on video-electroencephalographic monitoring, but very few patients have been explored with depth electrodes. We report a woman with late-onset epilepsy who had intractable seizures despite trials of several antiepileptic drugs. At the time of the depth-electrode recordings, seizures were usually continuous and occurred either spontaneously or were induced by movements of the jaw and mouth. The seizures originated in the deep central opercular cortex; localization was confirmed by a good surgical outcome.  相似文献   
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