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941.
The etiological complexity of the eating disorders has incited researchers to examine how personality characteristics and other variables operate jointly in the development of deviant eating patterns. OBJECTIVE: This study investigated the independent, interactive, and indirect prediction of dietary restraint by perfectionism and excessive commitment to exercise. METHOD: Multiple regression analyses designed to test moderating and mediating models were conducted on a sample of female university students (n = 269). RESULTS: Several dimensions of perfectionism, as well as excessive commitment to exercise, significantly and independently predicted dietary restraint in these women. There was no evidence for an interaction effect. Mediation analyses suggested that for selected dimensions of perfectionism, the direct relationship between perfectionism and dietary restraint is partially explained by excessive commitment to exercise. DISCUSSION: Interventions aimed at challenging perfectionistic standards in the context of dieting need to address not only one's self-standards, but one's perceptions of standards held by others. The mediating role of excessive exercise commitment pinpoints this variable as an alternative intervention target in the prevention of excessive dieting.  相似文献   
942.
943.
The aim of this study was to examine the prevalence of exercise limitation due to diastolic heart failure among patients felt to have cardiac breathlessness by their general medical practitioner but not referred to hospital. We found that 18% of patients had a simple investigated profile compatible with isolated diastolic dysfunction as a cause of their symptoms. Symptoms appeared to pre-date major cardiac events (infarction; stroke; arrhythmia) that dominated the subsequent clinical course. The patients in this group have adverse cardiovascular risk profiles. Obesity was a common co-morbidity which may impair detailed 2-D echocardiographic assessment.  相似文献   
944.
We have investigated the impact of neuromuscular activity on the expression of neurotrophins in the lumbar spinal cord region and innervating skeletal muscle of adult rats. Rats were exercised on a treadmill for 1 day or 5 consecutive days and euthanized at 0, 2 or 6 h after the last bout of exercise. By Day 1, there was no clear evidence of an increase in brain-derived neurotrophic factor (BDNF) mRNA in the spinal cord or the soleus muscle. By Day 5, there was a significant increase in BDNF mRNA in the spinal cord at 2 h post-training, and the soleus muscle showed a robust increase between 0 and 6 h post-training. Immunoassays showed significant increases in BDNF protein in the soleus muscle by training Day 5. Immunohistochemical analyses showed elevated BDNF levels in motoneuron cell bodies and axons in the ventral horn. Neurotrophin-3 (NT-3) mRNA was measured to determine whether selected neurotrophins respond with a selective pattern of induction to neuromuscular activity. In the spinal cord, there was a progressive post-training decrease in NT-3 mRNA following a single bout of training, while there was a significant increase in NT-3 mRNA at 2 h post-training by Day 5. The soleus muscle showed a progressive increase in NT-3 mRNA by Days 1 and 5 following training. These results show that neuromuscular activity has specific effects on the BDNF and NT-3 systems, and that repetitive exercise affects the magnitude and stability of these responses.  相似文献   
945.
1. The preventive effects of exercise and L-arginine intake on hypertension and thrombosis in stroke-prone spontaneously hypertensive rats (SHRSP) were studied. 2. Stroke-prone spontaneously hypertensive rats were divided into three groups: (i) the control, sedentary group; (ii) the exercise group, which was allowed to run voluntarily on running wheels; and (iii) the L-arginine intake group, which was given 2.25% L-arginine solution for 8 weeks from 4 to 12 weeks of age. In the control group, one rat died from stroke and symptoms of stroke were observed in the remaining animals. Similar symptoms were recorded in one rat of the exercise group, but not in the L-arginine group. 3. Blood pressure increased in the control group and this increase was suppressed significantly in the exercise and L-arginine groups. Thrombotic potential in cerebral vessels was the lowest at 4 weeks in all groups and was increased significantly at 12 weeks in the control group, but not in the exercise and L-arginine groups. Plasma concentrations of NO2/NO3 were lower in all animals at 12 weeks compared with those at 4 weeks. This reduction was significantly less marked in the L-arginine group. Cerebral arterioles in control rats at 12 weeks of age were significantly smaller in diameter than those at 4 weeks and these changes were less pronounced in the exercise and L-arginine groups. 4. The results provide clear evidence for the beneficial effects of L-arginine intake and voluntary exercise in mechanisms related to hypertension, thrombosis and stroke.  相似文献   
946.
Abstract. Henriksson, K. G. (Neuromuscular Unit, Department of Neurology, Clinical Neurophysiology and Pathology I, University of Linköping, Linköping, Sweden). Muscle histochemistry and muscle function. Acta Paediatr Scand, Suppl. 283: 15, 1980.—A short review of the histochemical characteristics of the different muscle fibre types is given. The possibility of changing contraction time, strength, and endurance by physical training is discussed.  相似文献   
947.
Abstract. Lauritzen, T., Binder, C. and Faber, O. K. (Steno Memorial Hospital, Gentofte, Denmark). Importance of insulin absorption, subcutaneous blood flow, and residual beta-cell function in insulin therapy. Acta Paediatr Scand, Suppl. 283: 81, 1980.—The interaction between variation in insulin absorption and beta-cell function was studied as well as the possible relation between subcutaneous blood flow through the region of injection and the variability in insulin absorption. The results indicate that the dose of insulin, the type of insulin preparation and the local blood flow influence the insulin absorption. Residual endogenous insulin secretion, governed by the blood glucose values, serves as a modulator.  相似文献   
948.
探讨慢性阻塞性肺病患者运动中生理死腔量及其与潮气量比值的变化与临床意义。方法无创性方法测定COPD和健康对照者静息与运动时潮气末二氧化碳分压、自动计算出VD及VD/VT比值,结果:COPD组运动能力与运动中最大通气量、最大摄氧量、最大潮气量、  相似文献   
949.
ResumeObjectifAugmenterl'exactitudedel'dpreuved'ellortsurtaxisroulant.MethodesDeuxmesuresoutdieprizespouraugmenterl'exactitudedel'dpreuve:(1)Seloniescaract,ristiquesdesdouleursthoraciquesdtabliesparuninterrogatoireddtalilld,distingueriespatientsendeuxgroupes:isch,miquesetnonischemiques,(2)AnalyserdelaConinderaleiesdilldrentsparamdtrestelsquedouleursthoraciques,d4PressiondusegmentST,raPPortSBP.S'ilyadeux(onplus)paramdtresanormaux,l'epreuveestconsiddrdecommepositive.acs"ltats(1)Dansiegroov…  相似文献   
950.
Gradual weight gain in modern people and a lowering onset age of metabolic disease are highly correlated with the intake of sugary drinks and sweets. Long-term excessive fructose consumption can lead to hyperglycemia, hyperlipidemia and accumulation of visceral fat. Abdominal obesity is more severe in females than in males. In this study, we used a high-fructose-diet-induced model of obesity in female mice. We investigated the effects of aquatic exercise training on body weight and body composition. After 1 week of acclimatization, female ICR mice were randomly divided into two groups: a normal group (n=8) fed standard diet (control), and a high-fructose diet (HFD) group (n=24) fed a HFD. After 4 weeks of induction followed by 4 weeks of aquatic exercise training, the 24 obese mice were divided into 3 groups (n=8 per group): HFD with sedentary control (HFD), HFD with aquatic strength exercise training (HFD+SE), and HFD with aquatic aerobic exercise training (HFD+AE). We conducted serum biochemical profile analysis, weighed the white adipose tissue, and performed organ histopathology. After 4 weeks of induction and 4 weeks of aquatic exercise training, there was no significant difference in body weight among the HFD, HFD+SE and HFD+AE groups. Serum triglyceride (TG), AST, ALT, and uric acid level were significantly lower in the HFD+SE and HFD+AE groups than in the HFD group. The weight of the perirenal fat pad was significantly lower in the HFD+AE group than in the HFD group. Hepatic TG and total cholesterol (TC) were significantly lower in the HFD+AE group than in the other groups. Long-term intake of a high-fructose diet can lead to obesity and increase the risk of metabolic disease. Based on our findings, we speculate that aquatic exercise training can effectively promote health and fitness. However, aquatic aerobic exercise training appears to have greater benefits than aquatic strength exercise training.  相似文献   
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