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61.
Exposure to wood preservatives containing pentachlorophenol (PCP) was detected in 65 women who consulted the Endocrinological Department of the University Hospital of Obstetrics and Gynecology, Heidelberg, Germany, because of gynecological problems. Blood PCP levels ranged from 20.7 to 133 microg per liter of serum. One hundred and six women with similar clinical conditions, corresponding age and body weight, no PCP exposure in history, and PCP levels below 20 microg per liter of serum served as control group. Significant associations were found between serum PCP concentrations, age, and different parameters of the endocrine system. PCP may act centrally on a hypothalamic or suprahypothalamic level which may result in mild ovarian and adrenal insufficiency. PCP may, therefore, play a role in the increasing infertility problem.  相似文献   
62.
Given the changes of gender roles in this century it is hardly justified to assume constant proportions of alcohol consumption for males and females. The purpose of the study was to reconstruct the consumption trends of males and females in Switzerland since the beginning of the 20th century. Cirrhosis mortality and survey data were used to disaggregate by sex the per capita alcohol consumption based on liver cirrhosis mortality suggests that the evolution of alcohol consumption in Switzerland followed a parallel course for both sexes only until the 1930 s. The low consumption during World War II and the evident increase until the beginning of the '60s seem to have resulted above all from the variations in consumption of beer by men. The decrease in total alcohol consumption observed since the '70s is also most probably due only to men; there is no indication of a decreasing consumption by women. The tendency of male and female consumption patterns to become more similar should be taken into account in the prevention of alcohol misuse.  相似文献   
63.
64.
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure - emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for90Y, with detection by positron emission tomography (PET). The study compared the properties of two different86Y complexes —86y-citrate and86Y -ethylene diamine tetramethylene phosphonate (EDTMP) — in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing90Y. In 1 cm3 of bone metastasis, doses of 26±11 mGy/MBq and 18±2 mGy/MBq were determined per MBq of injected90Y- citrate and90Y- EDTMP, respectively. The doses to the bone marrow were 2.5±0.4 mGy/MBq for90Y- citrate and 1.8±0.6 mGy/MBq for90Y-EDTMP.86Y and PET provide quantitative information applicable to the clinical use of90Y. This method may also be useful for the design of other90Y radiopharmaceuticals and for planning radiotherapy dosages.  相似文献   
65.
Summary The aim of the present study was to investigate the dose-dependent antiarrhythmic efficacy of lidocaine against electrically induced tachycardias in conscious, chronically instrumented postinfarction dogs. Programmed electrical stimulation (PES) was performed in 16 dogs 8 to 21 days after a 4 h occlusion of the left anterior descending coronary artery (LAD). Infusion of saline in 8 control animals with sustained ventricular tachycardia (SVT) inducible at baseline did not affect subsequent inducibility. In the treatment group 7 of 8 animals responded with SVT and one exhibited ventricular fibrillation at baseline. After an initial bolus of 1 mg/kg lidocaine intravenously (i.v.), the drug was infused at infusion rates of 40, 80 and 120 g/kg/min (i.v.). During 80 g/kg/min lidocaine (mean plasma level 3.5 g/ml) 7 out of 8 animals displayed an antiarrhythmic response; both the lower and the higher infusion rate were associated with a smaller antiarrhythmic efficacy (3 of 8 animals responded to 40 g/kg/min and 4 of 8 to 120 g/kg/min). Licocaine did not affect ventricular refractory periods, but induced an increase in intraventricular conduction time at all infusion rates, from 66.2 ms at baseline to 67.7 ms (p<0.05), 67.7 ms (p<0.05), 70.0 ms (p<0.01) respectively.In conclusion the present study demonstrates that lidocaine is of considerable value in the management of PES-induced ventricular arrhythmias in the postinfarction phase. However there is only a small optimal therapeutic plasma level range, where lidocaine exhibits its antiarrhythmic efficacy against this type of arrhythmia; this makes a carefully titration of the drug necessary both in the experimental and in the clinical setting. Send offprint requests to K. Krejcy at the above address  相似文献   
66.
Summary Oral MPA 1.5 g/day leads to plasma concentrations between 1 and 12 g/ml, with a broad intra-and interindividual variance. The plateau state is reached in between 4 and 16 days. Plasma concentrations in the plateau state are very sensitive to dose modifications. After cessation of administration, the decline in plasma levels seems to proceed in two phases, with half-times of about 20 h and 4 days. Extraction procedures reveal no benefit in discriminating between MPA and its metabolites.  相似文献   
67.
Because tyrosine and dopa can be regarded as precursors of adrenomedullary hormones and melanin, radioiodinated derivatives of these compounds were tested for their accumulation in the adrenal medulla and in melanomas of various animal species. The highest level of accumulation in the adrenal medulla was attained in mice and rats with iodinated -hydroxy--methyltyramine, and in melanomas of mice with iodinated -methyltyrosine. The results could not be reproduced to the same extent in other species.  相似文献   
68.
Zusammenfassung Es wird über die Kasuistik und die toxikologischen Untersuchungen im Fall einer Selbsttötung durch Trinken von Castrol®-Bremsflüssigkeit berichtet. Zum Nachweis und zur quantitativen Bestimmung des Giftes hat sich die Gaschromatographie als vorteilhaft erwiesen.  相似文献   
69.
Structural Elucidation of the Reaction Products from Benzonitrile Oxide and 1,4-Disubstituted Urazoles The reaction of benzonitrile oxide with 1,4-disubstituted urazoles 1 does not yield 1,4-disubstituted 3-(phenylcarbamyoloxy)--1,2,4-triazolin-5-ones 2 , as reported in the literature, but leads to N1′,N3′-disubstituted 3-phenyl-4-ureido--1,2,4-oxadiazolin-5-ones 4 .  相似文献   
70.
The aim of the present study was to quantify the distribution of the elastic fiber system within the wall of the anterior cerebral artery. The study is based on the works of Glynn (1940) and Stehbens (1989) concerning the incidence and origin of brain aneurysms and recent studies of the elastic fibers. The anterior cerebral artery was divided into three segments, S1, S2 and S3: S1 corresponds to the origin of the anterior cerebral artery, S2 is located at the junction of the anterior cerebral artery with the anterior communicating artery, and S3 at the junction of the rostrum and genu of the corpus callosum,which were submitted to routine histological procedures. A histomorphometrical study was undertaken using an estimation of the linear density (Ld) of the components of the fibrous elastic system which evaluates their full length in each segment. Data were analyzed using first order linear regression methods. The results show a decreasing quantity of elastic fibers in the three segments (S1>S2>S3). Study of the elastic fiber system may originate new concepts regarding the genesis of cerebral artery aneurysm.  相似文献   
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