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961.
962.
Cystic breast lesions are caused by a wide spectrum of breast diseases and can range from simple cysts to malignant tumors. Ultrasonography is a good tool for evaluation of the morphology and vascularity of cystic breast lesions. We report three patients in whom contrast-enhanced ultrasonography (CEUS) was used to evaluate intracystic tumors. One of the three patients was diagnosed with intracystic papilloma. Compared with conventional ultrasonography alone, CEUS more clearly demonstrated that the solid component within the mass was lobulated with a narrow base. The other two patients were diagnosed with intracystic papillary carcinoma, and CEUS clearly revealed the presence of widely elevated solid components within both masses, suggesting malignancy. Therefore, CEUS simplified morphological evaluation by enhancing the solid components within the cystic masses.  相似文献   
963.
The effect of a new chemical agent, SG 75, on coronary blood flow of anesthetized dogs has been examined. Intravenous administrations of this agent in a dose of 10 microgram/Kg or over caused a significant increase in blood flow of non-constricted coronary artery. Percent increases in flow were 40 (10 microgram/Kg), 95 (50 microgram/Kg), 145 (100 microgram/Kg), and 195 (250 microgram/Kg). The increases were significantly larger than those caused by the same doses of diltiazem, verapamil, nitroglycerin, isosolbide dinitrate, and papaverine. The durations of the increase in flow were 12 (10 microgram/Kg), 23 (50 microgram/Kg), 28 (100 microgram/Kg), and 46 min (250 microgram/Kg), and they were longer than those caused by diltiazem and verapamil. A slight reduction in left ventricular tension and an increase in aortic blood flow were also observed following the administrations of SG 75 in a dose of over 50 microgram/Kg. A decrease in heart rate was produced with a dose of over 500 microgram/Kg. However, PQ interval of electrocardiogram became shorter. Intravenous administrations of SG 75 in doses of 50 and 150 microgram/Kg caused an increase in blood flow of the constricted coronary artery, while nitroglycerin (10 and 30 microgram/Kg) and nifedipine (1 and 3 microgram/Kg) reduced it. The results indicate that SG 75 is a potent and long-acting coronary vasodilating agent and it causes an increase in blood flow of constricted as well as non-constricted coronary artery.  相似文献   
964.
This report is a case study of a vagrant whose state of tuberculosis showed noteworthy improvement due to clinical treatment. A 54-year-old male, vagrant, was admitted to the hospital in a state of preshock because of a serious stage of lung tuberculosis. The clinical course was severe, but after three months of intensive care the patient recovered. It was noted that the echocardiogram taken after recovery revealed improvement when compared with the one taken upon admission, which showed remarkable right ventricular overload. Furthermore, anti-tuberculosis agents proved to be very effective in this case. The patients respiratory functions improved more markedly than had been expected. The reason for reporting this case study is to bring attention to the improvements in the patient's clinical course and echocardiographic findings. These suggest that tuberculosis in vagrants may differ from the usual stage of tuberculosis diagnosed in elderly persons in terms of response to anti-tuberculosis agents and potential recovery.  相似文献   
965.
On the mechanism of termination and perpetuation of atrial fibrillation.   总被引:6,自引:0,他引:6  
In an effort to further clarify the mechanism of termination and perpetuation of atrial fibrillation (AF), the intraatrial potentials during AF induced by programmable electrical stimulation were analyzed using the concept of wavelength which represents the size of a microreentrant circuit. Thirty patients with inducible AF were divided into 2 groups: 20 patients with AF that terminated spontaneously (group 1) and 10 patients with AF that did not terminate spontaneously (group 2). Wavelength is the product of refractory period and conduction velocity. During AF, the refractory period of the local atrial tissue was considered to correlate with the mean interval between each intraatrial potential (mean ff). An inverse relation was considered present between conduction velocity of the impulse and the width of intraatrial potentials (f width). Thus, the wavelength index was defined as (mean ff)/(mean f width). Ten intraatrial potentials at the high right atrium were sampled for measurement. Group 1 had higher wavelength indexes just after the induction of AF than did group 2 (1.33 +/- 0.31 vs 1.10 +/- 0.05, p less than 0.05). In group 1, the wavelength indexes were increased from the initial value to 1.49 +/- 0.36 just before termination of AF (p less than 0.001). In 3 group 2 patients, AF stopped after disopyramide was administered intravenously, whereas the wavelength indexes at the end of AF were higher than those before drug administration (1.27 +/- 0.08 vs 1.16 +/- 0.04, p less than 0.05). In conclusion, prolongation of the wavelength appears to be a major determinant for termination of AF, and shorter wavelengths are necessary for perpetuation of AF.  相似文献   
966.
Correction     
The online version of the original article can be found at  相似文献   
967.
Androgen receptors (AR) were assayed for cirrhotic liver, adenomatous hyperplastic nodule (AHN), and hepatocellular carcinoma (HCC) which were removed by partial hepatic resection from five patients. There were three men and two women. Age ranged from 59 to 68 years. Underlying cirrhosis was macronodular in three and micronodular in two. AHN was present within HCC in two patients, but these two lesions were found in different lobes of the same liver in another two patients. Only AHN was seen in the last patient. ARs in the cytosol of cirrhotic liver ranged from nil to 12.8 fmol/mg of protein with the dissociation constant (Kd) of 3.2-20.3 x 10(-10) M. AHNs possessed ARs ranging from 4.0 to 27.6 fmol/mg of protein (Kd values, 7.4-21.0 x 10(-10) M. All HCC nodules had ARs ranging from 11.8 to 72.8 fml/mg of protein with Kd values of 5.3-27.1 x 10(-10) M. Thus, cytosolic AR concentrations were highest in HCC, lowest in cirrhotic liver, and intermediate in AHN. The present study seems to indicate that AHN may be a precancerous lesion and that androgen and its receptor play an important role in human hepatocarcinogenesis.  相似文献   
968.
Background: The warm‐up phenomenon observed after the second of two sequential exercise tests is characterized by an increased time to ischemia and ischemic threshold, and the latter is related to ischemic preconditioning. Previous studies have demonstrated that a single dose of glibenclamide, a cardiac ATP‐sensitive K (KATP) channel blocker, prevents ischemic preconditioning. This study aimed to investigate the effects of chronic treatment with glibenclamide during two sequential exercise tests. Methods: Forty patients with angina pectoris were divided into three groups: 20 nondiabetics (NDM), 10 patients with diabetes in treatment with glibenclamide (DMG) and 10 diabetic patients with other treatments (DMO). All patients underwent two consecutive exercise tests. Results: Heart rate and rate‐pressure product at 1.0 mm ST‐segment depression significantly increased during the second exercise test in NDM group (121.3 ± 16.5 vs 127.3 ± 15.3 beats/min, P < 0.001, and 216.7 + 43.1 vs 232.1 ± 43.0 beats·min?1·mmHg·102, P < 0.001), and in DMO group (114.1 ± 19.6 vs 119.6 ± 18.1 beats/min, P = 0.001, and 199.8 ± 36.6 vs 222.2 ± 29.2 beats·min?1·mmHg·102, P = 0.019), but it did not change in patients in DMG group (130.7 ± 14.5 vs 132.1 ±14.7 beats/min, P = ns, and 251.7 ± 47.2 vs 250.3 ± 42.8 beats·min?1·mmHg·102, P = ns). In the three groups, NDM, DMO, and DMG, the time to 1.0 mm ST‐segment depression during the second exercise test was greater than during the first (225.0 ± 112.5 vs 267.0 ± 122.3 seconds, P = 0.006; 187.5 ± 54.0 vs 226.5 ± 74.6 seconds, P = 0.029 and 150.0 ± 78.7 vs 186.0 ± 81.9 seconds, P < 0.001). Conclusion: The chronic use of glibenclamide may have mediated the loss of preconditioning benefits in the warm‐up phenomenon, probably through its KATP channel‐blocker activity, but without acting upon the tolerance to exercise.  相似文献   
969.
No consensus about the antigenicity of monocomponent insulin has yet been reached. We have therefore administered different insulin preparations to rabbits and rats to determine IgG and IgE antibody production. The preparations used were porcine monocomponent insulin, conventional bovine and porcine insulin powders, porcine b-component and synthesized porcine mono-desamido-insulin and hexa-desamido-insulin. In rabbits, porcine b-component was the most antigenic preparation, followed by conventional bovine and porcine insulins. No antibody production was observed with the other preparations. In rats the 60 h passive cutaneous anaphylaxis test showed virtually no insulin IgE antibody production in response to porcine monocomponent insulin. However, if porcine b-component or porcine hexa-desamido-insulin was employed both for sensitisation and as the challenging antigen, positive skin reactions were observed with demonstration of insulin IgE antibodies. Our results confirm the low antigenicity of the pharmaceutical preparation of porcine monocomponent insulin and suggest that porcine hexa-desamido-insulin and porcine b-component administration may result in the production of reagin-type antibodies.  相似文献   
970.
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