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21.
Pregnancies after in vitro fertilization and transfer of human blastocysts   总被引:10,自引:0,他引:10  
In a study of 29 cycles of IVF, ET was performed on day 5 after oocyte recovery when embryos had developed to the morula/blastocyst stage. Three preclinical pregnancies and three live births resulted (2 singleton and 1 twin), giving a viable PR per ET of 10%. It is concluded that while day 5 ET may well be important in terms of embryo biopsy for the preimplantation diagnosis of genetic disease, day 2 ET remains preferable for therapeutic IVF. Although these data would not support the introduction of day 5 ET into routine therapeutic IVF, delayed ET should be considered as an alternative approach to preimplantation diagnosis. Indeed, because the latter will generally involve the treatment of normal, fertile couples, it might be predicted that embryo survival rates, and thus the rate of pregnancy after day 5 ET, would be better than those presented here.  相似文献   
22.
The role of time in performance on many neuropsychological tests has been relatively neglected in the literature to date. Neuropsychological functioning in 90 male and female alcoholics and 65 peer controls was examined using both accuracy and time measures for four basic types of neuropsychological functioning: verbal skills, learning and memory, problem-solving and abstracting, and perceptual-motor skills. Alcoholics had significantly lower efficiency ratios (accuracy/time) than controls in each of the four areas, and had significantly lower overall accuracy and time scores. There were no significant Group x Gender interactions for efficiency, speed or accuracy scores, indicating that male and female alcoholics have similar deficits as a result of chronic alcoholism. The study is the first to apply systematically an empirical measure of neuropsychological efficiency to different areas of cognitive function; the results have implications for neuropsychological testing procedures.  相似文献   
23.
24.
Semantic (verbal) and figural memory impairment in alcoholics   总被引:1,自引:0,他引:1  
In two separate studies, episodic semantic (verbal) and figural-memory abilities as measured by the Wechsler Memory Scale (Russell Method) are compared in middle-aged detoxified male alcoholics and controls. Both studies gave rise to similar findings. Alcoholics recalled significantly less verbal and figural material at both immediate recall and 30-min delayed recall than did the controls. Contrary to expectation, compared to controls, alcoholics did not have a greater differential deficit for the figural material as compared with the verbal or a greater differential deficit on delayed than on immediate memory. The percentage of material recalled at the delayed testing, when taken as a function of the amount of material recalled immediately, did not differ for the two groups on the semantic or figural tasks in either study. Thus, rates of forgetting were equivalent in alcoholics and controls suggesting that the alcoholics' deficit lies in the initial acquisition process. Whether that deficit is in encoding or initial retrieval processes remains to be investigated. Implications for future research are given.  相似文献   
25.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
26.
The contribution of adrenoceptors and purine receptors in mediating neurogenic vasoconstriction was investigated in the autoperfused intestinal circulation of anaesthetised cats treated with atropine and propranolol. Prazosin (0.5 mg/kg) and yohimbine (1.5 mg/kg) reduced but did not abolish the vasoconstrictor responses to stimulation of the efferent sympathetic nerves. The inhibitory actions of the two antagonists were additive but even after alpha 1- and alpha 2-adrenoceptor blockade nerve stimulation still elicited a residual, frequency-related vasoconstriction. The initial, rapid, phase of this response was completely abolished after desensitisation of P2x-purinoceptors with a high dose (1.5 mg i.a.) of alpha,beta-methylene ATP. In the absence of alpha-adrenoceptor antagonists, alpha,beta-methylene ATP reduced neurogenic vasoconstriction particularly at low frequency (1 Hz) nerve stimulation, but also caused a short-lasting decrease in noradrenaline and methoxamine responses which indicates that the drug may have some non-specific effects on arterial smooth muscle. The results suggest that neurotransmission in arterial resistance vessels of the cat intestinal circulation is predominantly under adrenergic control mediated by postsynaptic alpha 1- and alpha 2-adrenoceptors, with a possible purine involvement in the initial rapid response of the blood vessels, particularly to low frequency nerve stimulation.  相似文献   
27.
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.  相似文献   
28.
The role of neutrophils (PMN) in acute renal failure (ARF) is controversial. Although the development of acute renal failure (ARF) frequently occurs in situations where there is partial activation of PMN (primed PMN) and mild renal ischemia, the interaction between primed PMN and ischemic organs has not been studied in any biological system. To define the interaction between primed PMN and mild renal ischemia, kidneys were made ischemic for 10 minutes in situ and reperfused by the isolated kidney technique with untreated PMN or PMN primed with low concentrations of lipopolysaccharide (LPS) or phorbol myristate acetate (PMA). We found that primed PMN had no effect on control (non-ischemic) kidneys and that untreated PMN did not cause injury to kidneys previously subjected to mild ischemia. However, addition of primed PMN to mildly ischemic kidneys caused severe injury. To determine the nature of renal injury, ischemic kidneys were reperfused with primed PMN and catalase (CAT) or the elastase inhibitor, Eglin C. In ischemic kidneys reperfused with LPS-primed PMN, Eglin C (but not CAT) was partially protective while in ischemic kidneys reperfused with PMA-primed PMN, CAT (but not Eglin C) was partially protective. Reperfusion with both CAT and Eglin C completely prevented the damaging effects of either LPS- or PMA-primed PMN. In conclusion, addition of primed but not untreated PMN causes ARF in mildly ischemic kidneys by PMN oxidant- and/or protease-mediated mechanisms. This synergism could account for the high frequency of ARF in conditions associated with prerenal azotemia and primed PMN.  相似文献   
29.
The synthesis and Class III antiarrhythmic activity of a series of 4-[(methylsulfonyl)amino]benzamides and sulfonamides are described. Selected compounds show a potent Class III activity and are devoid of effects on conduction both in vitro (dog Purkinje fibers) and in vivo (anesthetized dogs). Compounds having a 2-aminobenzimidazole group were found to be the most potent, and one compound having this heterocycle (5, WAY-123,398) was selected for further characterization. Compound 5 was shown to have good oral bioavailability and a favorable hemodynamic profile to produce a 3-fold increase of the ventricular fibrillation threshold and to terminate ventricular fibrillation, restoring sinus rhythm in anesthetized dogs. Voltage-clamp studies in isolated myocytes show that 5 is a potent and specific blocker of the delayed rectifier potassium current (IK) at concentrations that cause significant prolongation of action potential duration.  相似文献   
30.

1. 1. Acute effects of alcohol and diazepam on reaction time (RT) and event-related potential (ERP) measures were examined in 108 healthy male volunteers.

2. 2. The subjects engaged in a simple RT task at two levels of stimulus intensity during baseline and treatment sessions.

3. 3. Lower stimulus intensity produced increased RTs, increased ERP peak latencies, and suppression of peak amplitudes.

4. 4. Moderate and high doses of alcohol, and high doses of diazepam produced increased RTs. Alcohol suppressed P100 and N100 amplitudes, while diazepam suppressed P100 amplitudes only. P100 amplitudes were correlated to RTs under baseline and treatment conditions.

5. 5. These results were taken as evidence for impaired stimulus detection during alcohol and diazepam intoxication, with both drugs influencing sensory-perceptual processes and alcohol alone influencing the degree of attentiveness.

Author Keywords: alcohol; diazepam; event-related potentials; simple reaction time  相似文献   

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