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991.
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《Diagnostic Histopathology》2014,20(10):392-397
Lung neuroendocrine (NE) tumors consist of four histologic subtypes, which are usually classified based on a three-tiered prognostic scheme. They are typical carcinoid (TC) as low-grade malignant tumors, atypical carcinoid (AD) as intermediate-grade malignant tumors, and large cell NE carcinoma (LCNEC) and small cell lung carcinoma (SCLC), both of which are high-grade malignant tumors. This three-tiered classification is based solely on histologic grounds and is a source of controversy especially when dealing with borderline or “gray zone” categories (TC vs. AC, AC vs. LCNEC, LCNEC and SCLC). In this review, controversial issues regarding the histologic classification will be discussed, and an innovative grading system that incorporates Ki-67 labeling index will be described. In addition, the recently discovered molecular alterations involved in TC/AC, as well as pathways involved in high-grade NE carcinomas, will be discussed in order to elucidate the differences in pathogenesis and biology between carcinoid tumors and high-grade NE carcinomas.  相似文献   
993.
BackgroundAdenoid hypertrophy may cause sleep-disordered breathing and altered craniofacial growth. The authors conducted a study to gauge the accuracy of alternative tests compared with nasoendoscopy (reference standard) for screening adenoid hypertrophy.MethodsThe authors conducted a systematic review that included searches of electronic databases, hand searches of bibliographies of relevant articles and gray literature searches. They included all articles in which an alternative test was compared with nasoendoscopy in children with suspected nasal or nasopharyngeal airway obstruction.ResultsThe authors identified seven articles that were of poor to good quality. They identified the following alternative tests: multirow detector computed tomography (sensitivity, 92 percent; specificity, 97 percent), videofluoroscopy (sensitivity, 100 percent; specificity, 90 percent), rhinomanometry with decongestant (sensitivity, 83 percent; specificity, 83 percent) and clinical examination (sensitivity, 22 percent; specificity, 88 percent). Lateral cephalograms tended to have good to fair sensitivity (typically 61-75 percent) and poor specificity (41-55 percent) when adenoid size was evaluated but excellent to good specificity when airway patency was evaluated (68-96 percent).ConclusionsNo ideal tool exists for dentists to screen adenoid hypertrophy, owing to access constraints, radiation concerns and suboptimal diagnostic accuracy. Research is needed to identify a low-risk, easily acceptable, highly valid diagnostic screening tool.Practical ImplicationsAlthough lateral cephalograms (which have good to fair sensitivity) and a thorough medical history (which has good specificity) are imperfect individually, when they are used together, they can compensate for each other's weaknesses. This combined approach is the best tool available to dentists for screening adenoid hypertrophy.  相似文献   
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996.
ObjectiveTo identify predictors of the ovarian response to clomiphene citrate (CC) in infertile patients with polycystic ovary syndrome (PCOS).MethodsWe performed a prospective cohort study of infertile patients with PCOS. The participants underwent assessments of their physical, endocrine, and metabolic characteristics, and treatment with CC at an initial dose of 50 mg/day and a maximum of 100 mg/day between days 3 and 7 of their menstrual cycles. Participants who ovulated were identified as responders and those who did not as non-responders.ResultsOf the 72 participants, 48 (66.7%) were identified as responders and 24 as non-responders. Sex hormone-binding globulin (SHBG) (odds ratio 1.022, 95% confidence interval: 1.000–1.045) was found to be associated with the ovarian response to CC using logistic multivariate regression analysis. Receiver operating characteristic analysis also showed that SHBG was a significant predictor of the response to CC (area under the curve 0.799).ConclusionWe have shown that SHBG is the best prognostic indicator of an ovulatory response to CC. However, larger prospective studies, in which more variables are assessed, are required to confirm this finding and to identify appropriate cut-off values.  相似文献   
997.
To better characterize the role of the lipoprotein lipase (LPL) gene in the determination of triglyceride levels in healthy subjects, a study was performed in 193 nuclear families (384 parents, means age = 42.0 ± 5.2 years; 399 offspring, mean age = 14.6 ± 4.3 years) volunteering to have a free health checkup examination. The pattern of familial resemblance was compatible with a zero correlation between spouses, a weak father-offspring correlation (0.099 ± 0.054; P < 0.07), and significant mother-offspring (0.235 ± 0.053; P < 10−4) and sib-sib (0.294 ± 0.064; P < 10−4) correlations. Associations of triglyceride levels with the LPL HindIII and PvuII polymorphisms were investigated by a familial measured genotype analysis, specifying sex- and age-dependent polymorphism effects. The effects associated with both polymorphisms were significant only in fathers, the H+ and P+ alleles being associated with raised triglyceride levels. The HindIII and PvuII polymorphisms explained 3.5% and 3%, respectively, of the variability of triglycerides in fathers. The relationship was weakened after prior adjustment on body mass index, but remained significant for PvuII. Because of the lack of effect in mothers and offspring, the polymorphisms did not contribute to the covariance of triglyceride levels in relatives. In conclusion, this family study showed a weak relationship of the HindIII and PvuII polymorphisms to plasma triglyceride levels in young healthy male subjects. The effects detectable only in fathers suggest a possible modulation of the LPL expression by hormonal or lifestyle factors. © 1996 Wiley-Liss, Inc.  相似文献   
998.
Objective. We examined ethnic differences in self-reported functional status in a rural, population-based sample in North Carolina. Methods. Data from 1,197 African-American and Caucasian participants, aged 45 and older, in the Johnston County Osteoarthritis Project were analyzed using multiple logistic regression to examine ethnic differences in difficulty performing tasks of the Health Assessment Questionnaire (HAQ) and in risk factor profiles associated with difficulty. Results. Forty-three percent reported difficulty in one or more HAQ tasks. African-Americans were more likely than Caucasians to report difficulty performing 3 tasks (P < 0.04); these differences were minimal after adjustment for confounders. For some tasks, risk factor profiles included body mass index in African-Americans only, and age and female gender more often in Caucasians. Low educational attainment was part of the risk factor profile for walking in African-Americans. Conclusions. Differences in proportions of African-Americans and Caucasians reporting difficulty in performance of HAQ tasks were minimal, but risk factor profiles for difficulty appeared to vary by ethnicity.  相似文献   
999.
Background:Sarcoidosis, a multisystemic disease of unknown etiology, is characterized by non-caseating granulomatous inflammation. This study aimed to investigate the efficiency of atherogenic indices and ultrasonographic evaluation of carotid artery on predicting atherosclerosis in patients with sarcoidosis.Methods:The study included 44 subjects followed with diagnosis of sarcoidosis and 53 age and gender matched healthy subjects as controls. Laboratory findings, pulmonary function tests and carotid artery ultrasonography of all participants were evaluated.Results:Of the participants with sarcoidosis 70.5% was female and the mean age was 35.36±7.18 years, while 64.2% of the control group were female and the mean age was 33.58±8.13 years (P=0.511 and P=0.191, respectively). High-density-lipoprotein cholesterol level in the sarcoidosis group was significantly lower than that of the control group (P=0.017), while other cholesterol levels were higher than those of the controls (P<0.05). Intima-media thickness (IMT) and peak systolic velocity (PSV) of carotid artery were higher in patients with sarcoidosis (P<0.001 and P=0.009, respectively). Atherogenic indices (Atherogenic Index (AI), Atherogenic Coefficient (AC) and Cardiogenic Risk Ratio (CRR)) were higher in sarcoidosis group compared to the controls (P<0.001, for all parameters). IMT was positively correlated with PSV, AI, AC, and CRR. A positive correlation between PSV and atherogenic indices was also detected.Conclusions:Sarcoidosis may be a predisposing factor for atherosclerosis. Atherogenic indices, IMT of carotid artery and PSV might be considered predictors for atherosclerosis and cardiovascular diseases in asymptomatic sarcoidosis patients.  相似文献   
1000.
A relationship between vitamin D deficiency (VDD) and gestational diabetes mellitus (GDM) has been described. Considering that GDM prevalence depends on body mass index (BMI), our main objective was to determine if VDD is associated with GDM, independent of BMI. A cross-sectional study with 886 pregnant women was conducted in Elda (Spain) from September 2019 to June 2020. To assess the association, Poisson regression models with robust variance were used to estimate the prevalence ratio (PR). The observed GDM prevalence was 10.5%, while the VDD prevalence was 55.5%. In the crude model, both VDD and obesity were associated with GDM, but in the adjusted model, only VDD was statistically significant (PR = 1.635, p = 0.038). A secondary event analysis did not detect differences in VDD, but BMI yielded a higher frequency of births by cesarean section and newborns with a >90 percentile weight in the obesity group. In conclusion, VDD is associated with GDM, independent of BMI. Future longitudinal studies could provide information on causality.  相似文献   
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