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71.
BackgroundAsthma and chronic obstructive pulmonary disease (COPD) are airway diseases with similar clinical manifestations, despite differences in pathophysiology. Asthma-COPD overlap (ACO) is a condition characterized by overlapping clinical features of both diseases. There have been few reports regarding the prevalence of ACO in COPD and severe asthma cohorts. ACO is heterogeneous; patients can be classified on the basis of phenotype differences. This study was performed to analyze the prevalence of ACO in COPD and severe asthma cohorts. In addition, this study compared baseline characteristics among ACO patients according to phenotype.MethodsPatients with COPD were prospectively enrolled into the Korean COPD subgroup study (KOCOSS) cohort. Patients with severe asthma were prospectively enrolled into the Korean Severe Asthma Registry (KoSAR). ACO was defined in accordance with the updated Spanish criteria. In the COPD cohort, ACO was defined as bronchodilator response (BDR) ≥ 15% and ≥ 400 mL from baseline or blood eosinophil count (BEC) ≥ 300 cells/μL. In the severe asthma cohort, ACO was defined as age ≥ 35 years, smoking ≥ 10 pack-years, and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity < 0.7. Patients with ACO were divided into four groups according to smoking history (threshold: 20 pack-years) and BEC (threshold: 300 cells/μL).ResultsThe prevalence of ACO significantly differed between the COPD and severe asthma cohorts (19.8% [365/1,839] vs. 12.5% [104/832], respectively; P < 0.001). The percentage of patients in each group was as follows: group A (light smoker with high BEC) – 9.1%; group B (light smoker with low BEC) – 3.7%; group C (moderate to heavy smoker with high BEC) – 73.8%; and group D (moderate to heavy smoker with low BEC) – 13.4%. Moderate to heavy smoker with high BEC group was oldest, and showed weak BDR response. Age, sex, BDR, comorbidities, and medications significantly differed among the four groups.ConclusionThe prevalence of ACO differed between COPD and severe asthma cohorts. ACO patients can be classified into four phenotype groups, such that each phenotype exhibits distinct characteristics.  相似文献   
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Histone deacetylase (HDAC) inhibitors are currently being tested as anticancer agents in clinical trials. Chromatin remodeling, such as through histone acetylation, is a fundamental phenomenon in eukaryotic cell biology, bearing implications to numerous physiological and pathological phenomena. Here, we discuss recent data from our own laboratory and those of others demonstrating antifibrotic and renoprotective effect of HDAC inhibitors in diabetic kidneys, and the possible mechanisms including the role of reactive oxygen species. HDAC inhibitors may prove to be a novel class of multitarget agents in the treatment of diabetic nephropathy.  相似文献   
74.
Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.  相似文献   
75.
Parkinson??s disease (PD) is a progressive degenerative disorder of the central nervous system. Levodopa (L-dopa), dopamine precursor is the most effective therapeutic drug for PD patients. Levodopa (LDP) and its three metabolites in rat plasma were determined using high performance liquid chromatography coupled with tandem mass spectrometry (LC?CMS/MS). Method validation was conducted in terms of linearity, accuracy, precision, recovery, specificity, limit of detection, limit of quantification and stability. Correlation coefficients (r 2) were above 0.9965. The intra-day accuracy values at LLOQ (low limit of quantification), LQC (low quality control), MQC (medium quality control) and HQC (high quality control) levels were 85.7?C103.3, 96.5?C105.1, 90.7?C100.1 and 94.2?C101.3?%, respectively. The inter-day accuracy values at LLOQ, LQC, MQC and HQC levels were 77.6?C112.0, 91.1?C109.3, 84.3?C101.0 and 88.2?C103.9?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The recoveries (mean?±?%SD) for LLOQ, LQC, MQC and HQC were 82.7?±?3.7?C113?±?2.8?%, 86.6?±?5.7?C110.3±3.4?%, 90.9?±?3.6?C106?±?6.5 and 89.7?±?4.5?C97.4?±?6.7?%, respectively. The coefficient of variation (RSD) values of both intra- and inter-day results were within 6.7 and 8.5?%, respectively. The validated LC?CMS/MS method was applied successfully to the measurement of LDP and its metabolites in the rat plasma samples.  相似文献   
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77.
Although momilactone B has been studied as an allelochemical of rice (Oryza sativa L.), to date we have no report showing the effect of momilactone B on mammalian cells. This study was undertaken to examine whether this allelochemical has anticancer activity on cancer cells. We show here that momilactone B at micromolar doses has antitumor efficacy by inducing apoptosis in several blood cancer cells including human leukemic T cells. In addition, our study elucidated that anticancer activity of momilactone B on human leukemic T cells resulted from the induction of apoptosis via caspase and mitochondria. From these results, momilactone B can be considered as a novel therapeutic strategy for human leukemic T cells from its direct apoptosis-inducing activity.  相似文献   
78.
The effect of lycopene supplementation on the antioxidant system was investigated by analyzing lipid peroxide levels, glutathione contents, and antioxidant enzyme activities in Mongolian gerbils fed a high fat diet. Gerbils were fed on each experimental diet for 6 weeks; normal diet (NC), normal diet with 0.05% lycopene (NL), high fat diet (HF), and a high fat diet with 0.05% lycopene (HFL). Dietary supplementation of lycopene increased hepatic lycopene level in gerbils fed a normal or high fat diet (P < 0.05). Liver and erythrocyte concentrations of lipid peroxide increased in gerbils fed a high fat diet, whereas lycopene supplementation decreased liver and erythrocyte concentrations of lipid peroxide (P < 0.05). Hepatic total glutathione content was higher in the NL group than that in the NC group (P < 0.05). Total antioxidant status in plasma increased following lycopene supplementation compared with that of the non-lycopene supplemented groups (P < 0.05). Hepatic catalase activity increased following dietary lycopene supplementation (P < 0.05). Superoxide dismutase activity in liver remained unchanged with lycopene supplementation, but erythrocyte superoxide dismutase activity increased in NL group compared with NC group (P < 0.05). Glutathione-S-transferase activity increased in the NL group compared to NC group (P < 0.05). Liver and erythrocyte glutathione peroxidase activity increased significantly in the NL group compared to that in the HF group (P < 0.05). Liver glutathione reductase activity was higher in the NL group than that in the NC group (P < 0.05). These results suggest that lycopene supplementation may be efficient for preventing chronic diseases induced by oxidative stress related to high fat diet.  相似文献   
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The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.  相似文献   
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