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121.
Summary Urinary kallikrein excretion was studied in young, stroke-prone, spontaneously hypertensive rats (spSHR). Seven-week-old spSHR were found to excrete more kallikrein into the urine than normotensive Wistar Kyoto control rats (WKR). Chemical sympathectomy, induced by 6-hydroxydopamine (6-OHDA) immediately after birth, resulted in normotensive blood-pressure levels and in a reduction of kallikrein in spSHR. In normotensive WKR, blood pressure and urinary kallikrein excretion were only slightly diminished by 6-OHDA. The results suggest a relationship between sympathetic activity and kallikrein excretion, being especially pronounced in spSHR, which have an elevated sympathetic activity.Supported by the Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 90-Cardiovaskuläres System  相似文献   
122.
Summary Cystometric recordings were performed in pentobaribitone anaesthetized rats and the effects of gammaaminobutyric acid (GABA) mechanisms on urinary bladder function were evaluated as their influence on a bladder hyperactivity induced by 1-dihydroxyphenylalanine (l-DOPA) after peripheral decarboxylase inhibition. The bladder response was inhibited by intracerebroventricular (i.c.v., 4th ventricle) injections of GABA (250 g), muscimol (0.2 g) and glycine (1,000 g) as well as by systemically administered muscimol (4 mg/kg) and diazepam (2 mg/kg). Intravenous (i.v.) bicuculline, but not i.v. strychnine, antagonized the inhibitory actions of intraperitoneal (i.p.) and i.c.v. muscimol and i.v. diazepam while the opposite was true for the inhibitory action of i.c.v. glycine. In rats not pretreated with l-DOPA, i.p. administration of bicuculline (4 mg/kg) after 15 min caused prominent detrusor contractions that were prevented by an infracollicular brain transection.It is suggested that GABA synapses in the pontinemesencephalic brain region may be involved in the modulation of urinary bladder function.  相似文献   
123.
Summary Capillary gas chromatographic (GC) methods using sulphur and mass selective detection for the qualitative and quantitative determination of tetrahydrophtalimide (THPI) and 2-thiothiazolidine-4-carboxylic acid (TTCA), urinary metabolites of the fungicide captan in rat and humans, were developed. Urinary detection limits were 2.7 g/l for THPI and 110 g/l for TTCA. Intraperitoneal and oral administration of captan to rats resulted in a 48-h cumulative urinary excretion of THPI of 1%–2% and 3%–9% of the dose, respectively. Cumulative urinary excretion of TTCA over 48 h ranged from 2% to 5% of the captan dose for the respective routes of administration. In urine of non-exposed human subjects, neither THPI nor TTCA could be detected. In urine of fruit-growers who were occupationally exposed to captan, both THPI and TTCA could be detected. Based on these results, THPI and TTCA are proposed as promising parameters for the biological monitoring of occupational exposure to captan.  相似文献   
124.
The effect of deltamethrin pretreatment on the pharmacokinetics and metabolism of antipyrine was studied in male rats. The total plasma clearance of antipyrine was significantly decreased by deltamethrin pretreatment (20 mg/kg and 40 mg/kg daily for 6 days prior to antipyrine administration), while the elimination half-life at phase, the area under the concentration-time curve and the mean residence time of antipyrine were significantly increased. The magnitude of the observed changes was dose dependent. The urinary excretion of norantipyrine, 4-hydroxyantipyrine and 3-hydroxymethylantipyrine was decreased by 39%, 32% and 26%, respectively (p<0.001) in the presence of deltamethrin. In addition, the rate constants for formation of each of these metabolites were significantly decreased by an average of approximately 71%. These results suggest that deltamethrin is capable of inhibiting oxidative metabolism, a finding which could be of clinical and toxicological significance.  相似文献   
125.
Summary We have followed a large population of patients receiving radiation treatment for bladder carcinoma with respect to survival and recurrence-free survival. Bivariate and multivariate life table analyses have been performed using a set of independent variables. The most important were T class, grade (G), urinary carcinoembryonic antigen (U-CEA) taken before treatment and cytological analysis 4 months after treatment. We compared the usual way of classifying a patient (T+G) with the combination of U-CEA and cytology since the latter two variables seemed to have great prognostic importance. The analyses show that T+G gives the best significance for survival (P=0.0003) while U-CEA and cytology is better for recurrence-free survival (=0.0002). 0.0002).  相似文献   
126.
Summary The effects of the competitive angiotensin II antagonist saralasin (1-sarcosine-8-alanine-5-isoleucine-angiotensin II) on renal function in healthy rats and in rats with myohemoglobinuric acute renal failure were studied. Acute renal failure was induced by an intramuscular injection of 50% glycerol (10 ml ·kg–1). Functional impairment of the glycerol treated animals consisted in a decrease of renal blood flow (electromagnetic flowmeter) and GFR and in an increase of urine volume and arterial blood pressure.In healthy rats saralasin (6 g·kg–1·min–1 i.v.) had no renal effects by itself but antagonized the angiotensin II (200 ng·kg–1·min i.v.) induced fall of renal blood flow and GFR and the increase of arterial blood pressure. Given to glycerol treated animals saralasin did not induce any change of arterial blood pressure, renal blood flow, GFR or the urinary excretion of fluid and sodium.Supported by Deutsche Forschungsgemeinschaft  相似文献   
127.
Summary Five healthy male volunteers received 500 mg Aldactone® orally together with 100 Ci 3H-20-21-spironolactone; one elderly patient received 1 mCi 3H-spironolactone without additional cold drug. For 6 days the disposition kinetics of the drug were studied in plasma, urine and feces. The tritium concentrations in plasma reached a peak between 25–40 min after administration amounting to 2–3% of the dose/1. Up to the 12th h, they fell rapidly and showed a monoexponential decline (t 1/2 : 2.57±0.27 days) between the 36th and 96th h. Later, a striking increase in the speed of elimination of radioactivity from plasma (t 1/2 : 1.66±0.21 days) was observed. The biological half-life of labeled material in plasma was longer than that of fluorigenic compounds. 47–57% of the dose were excreted in urine and the remaining amount culd be detected in feces (total recovery 90%). The half-life of the urinary excretion rate was distinctly shorter (t 1/2 : 0.9±0.11 days) than that of total radioactivity in plasma. This, together with an observed increase of the polar fraction in urine from 35 up to 85%, which was accompanied by a decrease in plasma from 55 to 35%, suggests either tubular reabsorption or enterohepatic recirculation of lipophilic compounds. TLC-separation of the lipophilic fraction in urine revealed two previously unknown compounds of which the main congener was identified as 3-(3-oxo-7-methylsulfonyl-6, 17-dihydroxy-4-androsten-17-yl) propionic acid -lactone, as well as canrenone and the metabolites which have already been described (Karim and Brown, 1972; Karim et al., 1975). This metabolite represents the main lipophilic degradation product in urine within the first hours, whereas the 6-OH-7-methylsulfinylspirolactone leveled off and seemed to be an endexcretion product. For further characterisation, the polar fraction was subjected to acidic hydrolysis. The known metabolic pathways of spironolactone degradation are discussed.The paper includes parts of the thesis of G. Luszpinski  相似文献   
128.
m-Dinitrobenzene intoxication due to skin absorption   总被引:1,自引:0,他引:1  
Summary A case of m-dinitrobenzene intoxication is described. Clinical picture of the patient who was exposed to an industrial material containing m-dinitrobenzene, methaemoglobinemia and excretion of urinary metabolites observed in a volunteer who experimentally worked with the same material, absence of m-dinitrobenzene in the ambient air during the exposure, and penetration of m-dinitrobenzene through the protective gloves which were used by the patient indicate that m-dinitrobenzene was the toxic agent and that the main route of the invasion was skin absorption.  相似文献   
129.
目的 探讨尿激酶型纤溶酶原激活剂及其抑制剂在喉癌中的表达及与临床病理各参数及预后的关系。方法 采取免疫组化链霉卵白素生物素过氧化酶法 (labeled streptoavidin biotin peroxidase,SAB)法 ,对 10 4例喉鳞状细胞癌标本中的尿激酶型纤溶酶原激活剂 (urokinase typeplasminogenactivator,uPA)、抑制剂 (plasminogenactivatorinhibitors ,PAI)PAI 1和PAI 2表达情况进行检测。结合临床随访 ,经Kaplan Meier生存曲线、log rank检验及Cox比例风险模型分析其与临床病理参数及患者生存预后的关系。结果 uPA、PAI 1、PAI 2在喉癌组织中的表达分别为 66 3 %、70 2 %、5 0 0 %。uPA、PAI 1、PAI 2的阳性表达在颈部淋巴结转移组与非转移组中差异有显著性 ,经半定量分析P值分别为 0 0 10、0 0 2 7、0 0 3 8。单因素分析显示 :淋巴结转移及复发、肿瘤细胞分化程度、uPA和PAI 2表达是影响患者预后的因素。多因素分析提示 :淋巴结转移及复发、临床分期、uPA和PAI 2是影响患者预后的独立因素。结论 uPA在喉癌转移中起着重要的作用 ;PAI 1的作用复杂 ,可能不单纯是uPA的抑制剂 ;PAI 2可能是uPA主要抑制剂 ,由于其表达不足尚不能抑制uPA的活性  相似文献   
130.
The aim of the present study was to examine subpreputial bacteriology and to compare it with the urine cultures of healthy male children. Seventy-two male children were divided into two groups as A and B according to age. In both groups preputial sac and urine cultures were taken simultaneously. Gram (+) enteric cocci were the most common isolated pathogens from the preputial sac in group B. Enterobacter, E. coli and staphylococci species were isolated from the urine cultures of three patients in group B. We could not find any difference between the preputial sac swabs of group A and B patients, but the isolation rate of urine cultures of group A patients was significantly higher than group B (p < 0.05). The findings of the present study support a potential role of the prepuce acting as a reservoir of faecal bacteria in the pathogenesis of UTI in male infants, especially in the first year of life. Improved penile hygiene after the first year of life does not alter the subpreputial bacteriology, but significantly decreases the contamination of urine. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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