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991.
992.
The cognitive and motor deficits associated with human immunodeficiency virus-1 (HIV-1) infection have been studied using neurological examination and neuropsychological tests. However, drug users with HIV-1 infection generally have been excluded from such studies. Forty-four well-characterized drug users stratified by Centers for Disease Control staging were administered a standardized neurological examination and a battery of neuropsychological tests under single-blind conditions designed to minimize the acute effects of psychoactive substances. The results of the blind neurological examination were consistent with the previously ascertained clinical staging of HIV-1 infection. The pattern of neuropsychological deficits across HIV-1 states was similar to those found in cohorts of homosexual men.  相似文献   
993.
The metacognitive skills or monitoring, analyzing, predicting, planning, evaluating, regulating, and revising frame the nursing process and support clinical reasoning. Nurse educators who encourage metacognitive skill acquisition are likely to accelerate student comprehension, understanding, and mastery or nursing diagnosis, nursing process, and clinical reasoning. The models presented in this article have implications for teaching and learning clinical/ diagnostic reasoning.  相似文献   
994.
This study determined the dose-response relationship among three doses of betaxolol compared with placebo in patients with mild-to-moderate hypertension. In this double-blind, placebo-controlled trial, 317 hypertensive patients were randomly assigned to receive placebo or betaxolol 5, 10, or 20 mg once daily for 4 weeks. A significant (P less than .05) decrease in supine diastolic blood pressure (BP) compared with concurrent placebo was evident with all three doses of betaxolol after 1 week of active treatment. Each dose of betaxolol maintained a significant reduction in diastolic and systolic BP and heart rate responses throughout the 4-week treatment period. At the fourth week (final treatment evaluation), BP and heart rate were significantly (P less than .05) reduced by all three doses of betaxolol compared with placebo. For supine systolic and diastolic BP, the decreases with betaxolol 20 mg were significantly (P less than .05) greater than with the 5 mg dose, but there was no statistically significant difference between the 10-mg and either the 5- or 20-mg doses. For standing diastolic BP, the effect of betaxolol 5 mg once daily was significantly (P less than .05) less than that of 10 and 20 mg. The overall supine diastolic BP response to betaxolol was dose dependent, and more patients responded to the 10- and 20-mg doses of betaxolol (66% and 76%, respectively) than to the 5-mg dose (59%). For each efficacy variable, the absolute magnitude of the reduction was greater with increasing dose. In subgroup analyses, BP responses were analyzed by race, age, baseline BP, and age combined with baseline BP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
996.
AIMS: To develop and validate an empirical equation to screen for dysglycaemia [impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and undiagnosed diabetes]. METHODS: A predictive equation was developed using multiple logistic regression analysis and data collected from 1032 Egyptian subjects with no history of diabetes. The equation incorporated age, sex, body mass index (BMI), post-prandial time (self-reported number of hours since last food or drink other than water), systolic blood pressure, high-density lipoprotein (HDL) cholesterol and random capillary plasma glucose as independent covariates for prediction of dysglycaemia based on fasting plasma glucose (FPG)>or=6.1 mmol/l and/or plasma glucose 2 h after a 75-g oral glucose load (2-h PG)>or=7.8 mmol/l. The equation was validated using a cross-validation procedure. Its performance was also compared with static plasma glucose cut-points for dysglycaemia screening. RESULTS: The predictive equation was calculated with the following logistic regression parameters: P=1+1/(1+e-X)=where X=-8.3390+0.0214 (age in years)+0.6764 (if female)+0.0335 (BMI in kg/m2)+0.0934 (post-prandial time in hours)+0.0141 (systolic blood pressure in mmHg)-0.0110 (HDL in mmol/l)+0.0243 (random capillary plasma glucose in mmol/l). The cut-point for the prediction of dysglycaemia was defined as a probability>or=0.38. The equation's sensitivity was 55%, specificity 90% and positive predictive value (PPV) 65%. When applied to a new sample, the equation's sensitivity was 53%, specificity 89% and PPV 63%. CONCLUSIONS: This multivariate logistic equation improves on currently recommended methods of screening for dysglycaemia and can be easily implemented in a clinical setting using readily available clinical and non-fasting laboratory data and an inexpensive hand-held programmable calculator.  相似文献   
997.
In inbred miniature swine, semi-identical liver allograft recipients survive up to 3 months without immunosuppression, whereas similarly mismatched kidney allografts are uniformly rejected within 2 weeks. The early biological and immunological events were assessed in this unique model. SLA(d/d) pigs (MGH, Harvard Medical School, Boston, MA, USA) received liver or kidney allograft from heterozygous SLA(c/d) miniature swine. Survival, graft function, histology, intragraft cytokines, peripheral lymphocyte and platelet count, plasma cortisol level and cellular/humoral anti-donor immune response were assessed. Kidney allografts were uniformly rejected within 2 weeks, whereas liver allografts survived for up to 87 days. After both liver and kidney transplantation, the peripheral lymphocyte count decreased during the first week concomitantly to a significant elevation of plasma cortisol level. Early decrease of peripheral platelet count was observed after liver but not renal transplantation. Up-regulation of transforming growth factor beta1 (TGF-beta1) and interferon-gamma (IFN-gamma) was observed during the first postoperative week in semi-identical liver allografts and IFN-gamma as well as IL-10 in kidney allografts. In liver recipients, labelled autologous lymphocytes accumulated in the liver graft and native spleen, whereas after renal allograft, lymphocytes accumulated in the native spleen and liver but never in the kidney allograft. Specific cellular anti-donor unresponsiveness was observed from the first post-transplant day in both liver and kidney recipients, while the humoral anti-donor response remained intact. In semi-identical liver allograft, recipient rejection is milder and slower than in similarly matched kidney allograft. The intragraft up-regulation of TGF-beta1 in semi-identical liver allograft might be one mediator to explain the modulation of rejection after liver transplant. The rapid, nonspecific accumulation of recipient lymphocytes in the liver allograft but not in kidney allograft might also play a role in the different survival time in this model.  相似文献   
998.

Background  

Pyrethroid insecticides are widely used for insect pest control in Cameroon. In certain insect species, particularly the malaria vector Anopheles gambiae, resistance to this class of insecticides is a source of great concern and needs to be monitored in order to sustain the efficacy of vector control operations in the fields. This study highlights trends in DDT and pyrethroid resistance in wild An. gambiae populations from South Cameroon.  相似文献   
999.
Ohne ZusammenfassungDie Arbeit wurde durchgeführt mit Unterstützung des Kuratoriums der Freiburger Wissenschaftlichen Gesellschaft, der auch an dieser Stelle gedankt sei.  相似文献   
1000.
BACKGROUND: Bilateral removal of the olfactory bulbs (OBX) in rats results in a complex constellation of behavioral, neurochemical, neuroendocrine, and neuroimmune alterations, many of which are also reported in patients with major depressive disorder (MDD). Drawing on clinical findings, there has been considerable interest in the role of serotonin in the mechanism of action of OBX. However, to date, there has been no report of direct measurement of serotonergic functioning of bulbectomized animals using microdialysis. The present study describes the effects of olfactory bulbectomy on functioning of the serotonergic system. METHODS: In vivo microdialysis was performed in conscious rats that underwent OBX or sham surgery. Alterations in the functioning of the serotonergic system were assessed by administration of fluvoxamine, fenfluramine, and 3-hydroxybenzylhydrazine (NSD-1015). Animals were also repeatedly tested in an open field. RESULTS: Bilateral removal of the olfactory bulbs decreased basal extracellular levels by decreasing the releasable pool of serotonin (5-HT) in the basolateral amygdala 2 weeks after surgery and in the dorsal hippocampus 2 weeks and 5 months after surgery. Olfactory bulbectomized animals showed a lower rate of 5-HT synthesis under basal conditions. However, the capacity of the system to synthesize 5-HT was not affected. Olfactory bulbectomized rats were hyperactive in the open field. This hyperactivity remained after successive testing, indicating permanent behavioral changes. CONCLUSIONS: This microdialysis study shows that OBX has profound and long-lasting effects on serotonergic functioning and on activity levels and is therefore considered an intriguing and promising animal model for affective processes in the brain.  相似文献   
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