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81.
Melatonin stimulates the activity of protective antioxidative enzymes in myocardial cells of rats in the course of doxorubicin intoxication 总被引:1,自引:0,他引:1
Dziegiel P Murawska-Ciałowicz E Jethon Z Januszewska L Podhorska-Okołów M Surowiak P Zawadzki M Rabczyński J Zabel M 《Journal of pineal research》2003,35(3):183-187
The study aimed at determining the effect of melatonin on the activity of protective antioxidative enzymes in the heart and of lipid peroxidation products in the course of intoxication with doxorubicin (DOX). The rats were categorized into four groups, receiving: 0.9% NaCl i.p. (NaCl control); melatonin [20 mg/kg body weight (b.w.)] s.c. (control Mel); DOX (2.5 mg/kg b.w.) i.p.; melatonin plus DOX in doses as above. All the substances were administered once in a week for four consecutive weeks. Homogenates of heart tissue were examined for activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), levels of reduced glutathione (GSH) and of lipid peroxidation indices (MDA + 4-HDA). Administration of melatonin alone did not induce alterations in levels of MDA + 4-HDA, GSH, or in activity of GPx, SOD or CAT, as compared to the group receiving 0.9% NaCl. GSH levels decreased following DOX but remained at normal levels following DOX and melatonin. The level of MDA + 4-HDA increased following DOX, as compared with the control, a change prevented by the combination of DOX + melatonin. Activities of GPx, SOD and CAT were higher in groups receiving DOX and/or DOX plus melatonin than in control groups. Activity of CAT and the level of GSH in the group receiving DOX plus melatonin were significantly higher than in the group intoxicated with DOX alone. The obtained results demonstrate that, when given in parallel with DOX, melatonin protects cardiomyocytes from damaging effects of the cytostatic drug (reflected by the levels of MDA + 4-HDA). The protective effect resulted, in part from the augmented levels of GSH and from stimulation of CAT activity by melatonin in cardiomyocytes subjected to the action of DOX. 相似文献
82.
BACKGROUND: Modern therapy of acute myocardial infarction (AMI) is aimed at rapid and persisting restoration of blood flow in an infarct-related artery (IRA). However, in some patients myocardial reperfusion is not achieved in spite of effective IRA recanalisation. Myocardial Blush Grade (MBG) is one of the angiographic markers useful for the detection of this phenomenon. AIM: To assess the prognostic value of MBG in patients with anterior AMI treated with primary angioplasty. METHODS: The study group consisted of 104 patients (74 males, 30 females, mean age 62+/-13 years) treated with primary angioplasty due to anterior ST-segment elevation AMI. MBG was assessed after the procedure. The mortality and major cardiovascular event (MACE) rates were analysed one and six months after AMI. RESULTS: Patients with preserved myocardial reperfusion following angioplasty (MBG 2-3, n=64 (61.5%)) had a trend towards lower one-month mortality and significantly reduced six-month mortality compared with 40 (38.5%) patients with an impaired (MBG 0-1) myocardial reperfusion (3% vs 12.5%, NS; and 6.25% vs 20%, p<0.05, respectively). The rate of MACE was significantly lower in patients with rather than without reperfusion both after one and six months of follow-up (9.4% vs 27.5%, p=0.027 and 12.5% vs 42.5%, p<0.001, respectively). Compared with patients with a high MBG score, patients with altered reperfusion more frequently had diabetes (30% vs 12.5%, p=0.04), hypertension (67.5% vs 45%, p=0.043), longer time from the onset of symptoms to balloon inflation (355.9+/-199 min vs 215.5+/-113 min, p<0.001) and lower left ventricular ejection fraction, measured 3 days after AMI (43.3%+/-8 vs 47.4%+/-9, p=0.02). CONCLUSIONS: MBG has a significant prognostic value in patients with anterior AMI treated with primary angioplasty. Diabetes, hypertension and long delay of treatment are associated with the impairment of myocardial reperfusion. 相似文献
83.
Subacute stent thrombosis following coronary angioplasty: incidence and risk factors 总被引:1,自引:0,他引:1
Lesiak M Grajek S Pyda M Skorupski W Mitkowski P Grygier M Prech M Paradowski S Cieśliński A 《Kardiologia polska》2003,59(11):408-416
BACKGROUND: Subacute stent thrombosis was a significant complication in the early years of coronary stenting, often leading to myocardial infarction, need for urgent surgery or even death. The introduction of intracoronary ultrasound enabled the identification and proper treatment of the main causes of stent thrombosis, reducing the rate of this complication to 1%. AIM: To identify risk factors of subacute stent thrombosis. METHODS: Data concerning 845 procedures with a single stent implantation in patients with stable or unstable angina, undergoing this procedure between 1998 and 2000, were analysed. RESULTS: Subacute stent thrombosis occurred in 13 (1.54%) patients. Risk factors for this complication included urgent procedures (so-called bailout stenting), improper pre-treatment with drugs ("ad hoc" procedures), dissection uncovered by stent, and poor final result of procedure (higher degree of residual stenosis). The majority of these patients developed myocardial infarction in spite of the fact that the patency of stented vessel was quickly achieved in all but one patient. CONCLUSIONS: Urgent stenting, improper drug pre-treatment and suboptimal result of the procedure are the risk factors of subacute stent thrombosis. 相似文献
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Iwona Krela-Kazmierczak Aleksandra Szymczak-Tomczak Maciej Tomczak Liliana Lykowska-Szuber Piotr Eder Marcin A. Kucharski Kamila Stawczyk-Eder Katarzyna Waszak Jacek Karczewski Agnieszka Dobrowolska 《Archives of Medical Science》2021,17(3):662
IntroductionIn inflammatory bowel diseases (IBD), osteopenia and osteoporosis constitute a significant medical problem. Cytokines, especially IL-17, play an important role in the pathogenesis of IBD and osteoporosis. Vitamin D is a regulator of bone metabolism, and helps maintain immune system homeostasis.Material and methodsThe research sample consisted of 208 persons: 83 patients (age 35 ±11.99 years) with Crohn’s disease (CD); 86 patients (age 39.58 ±14.74 years) with ulcerative colitis (UC); and 39 persons (age 30.74 ±8.63 years) in the control group (CG). Clinical data on bone mineral density of the lumbar spine (L2-L4), bone mineral density of the femoral neck (FN), and body mass index (BMI) were collected. 25OHD and IL-17 serum concentrations were also measured.ResultsBody mass index (kg/m2) results: in CD, 21.51 ±3.68; in UC, 23.31 ±4.38; and in CG, 24.57 ±3.45 (p < 0.01). Densitometry results for L2–L4 T-score SD: in CD –0.83 ±1.45; in UC –0.47 ±1.15; in CG 0.09 ±0.70. Densitometry results for FN T-score SD: in CD –0.62 ±1.26; in UC –0.29±1.17; in CG 0.41 ±1.03 25OHD (ng/ml) serum concentrations: in CD, 21.33±12.50; in UC, 22.04±9.56; in CG, 21.56±9.11 (ns). IL-17 (pg/ml) serum concentrations: in CD, 8.55±10.99; in UC, 11.67±12.97; in CG, 5.16±9.11 (ns).ConclusionsInflammatory bowel diseases patients and persons from the CG did not differ in vitamin D or IL-17 levels. Patients with a mild course of the disease had a higher vitamin D concentration and bone mineral density. In UC, higher vitamin D concentrations were associated with lower IL-17 concentrations. The IBD patients with a severe course of the disease had a lower body mass than those in the CG and the patients with a mild course of the disease. 相似文献
88.
Joanna Lewek Izabela Jatczak-Pawlik Marek Maciejewski Piotr Jankowski Maciej Banach 《Archives of Medical Science》2021,17(3):818
IntroductionCoronavirus disease 2019 (COVID-19) may affect many organs and may be responsible for numerous complications including cardiovascular problems.MethodsWe analysed consecutive patients (n = 51) admitted to the cardiology department between 1st October 2020 and 31st January 2021 due to symptoms which might have reflected cardiovascular complications following COVID-19. We collected data concerning clinical characteristics, results of laboratory tests, echocardiography and 24-hour ambulatory ECG recording.ResultsThe post-COVID-19 complications appeared 1–4 months after disease recovery. Severe cardiovascular complications were observed in 27.5% of hospitalized patients. In comparison to those with mild complications, patients with severe complications had significantly higher prevalence of diabetes (36 vs. 8%; p = 0.01), decrease in ejection fraction (36% vs. 0%, p < 0.001), higher resting heart rate at admission (85 vs. 72 bpm; p < 0.001), and higher levels of C-reactive protein (p = 0.02) and troponin T (17.9 vs. 4.2 pg/ml; p = 0.01). Dyspnoea and exercise intolerance were also more frequent in patients with severe complications.ConclusionsDiabetes, elevated level of CRP and troponin, heart rate variability parameters and worsening of left ventricular ejection fraction are related to the severity of cardiovascular complications following COVID-19 infection. 相似文献
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