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981.
F Schr?der F Poley 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(7):191-192
In the fine needle aspiration cytology of the thyroid gland by the moistening of cannule and syringe with heparin or citric sodium rather disadvantages for the evaluation are the result. Artificial changes are most clearly to be seen in heparin. ACD-buffer does indeed not bring about any artefacts, does, however, also not show any provable advantages. In the fine needle biopsy the additives mentioned are entirely avoidable. 相似文献
982.
Michael J. Eckardt PhD Robert R. Rawlings MS Barry I. Graubard MA Vivian Faden PhD Peter R. Martin MD Louis A. Gottschalk MD PhD 《Alcoholism, clinical and experimental research》1988,12(1):88-93
Commonly used neuropsychological tests were administered to 91 detoxified alcoholics at the beginning of treatment. Statistically significant relationships were observed between test scores and post treatment consumption determined 8 months after completing treatment for 72 patients. The results varied depending upon the particular measure of posttreatment consumption evaluated and the type of statistical analysis used. The most consistent relationships were often counter to the notion that increased neuropsychological performance is correlated with a more favorable treatment outcome. Neuropsychological evaluation is of limited clinical utility in predicting posttreatment alcohol consumption. 相似文献
983.
The effects of dopamine administered in graded intravenous bolus injections (0.1 to 51.2 micrograms.kg-1) were studied simultaneously in a number of splanchnic vessels at organ level in anesthetized dogs with and without preceding administration of phenoxybenzamine. Hemodynamic data are presented for each artery as conductance, which were obtained by dividing mean flow by mean arterial pressure. The data were analyzed by two different means: 1) the response to 12.8 micrograms of dopamine during one minute, and 2) by dose-response curves. Early and late effects during the one minute post injection measurement time could be distinguished after the administration of dopamine. In the superior pancreaticoduodenal, the superior mesenteric, the inferior mesenteric, the left gastric, and the hepatic arteries an early reduction in conductance was seen, while in the femoral artery an increase in conductance was observed. Early reduction was often followed by an increase in conductance above the preinjection level. This early reduction in conductance was absent when dopamine was administered after phenoxybenzamine, while a more pronounced increase was observed during the late phase. There was a slight reduction in renal artery flow, probably caused by a slight reduction in arterial pressure. Because there was no increase in the conductance of the hepatic artery--both with and without phenoxybenzamine--it may be concluded that no specific dopamine receptors are present in this vascular bed in dogs. 相似文献
984.
The significance of an isolated central nervous system relapse, occurring as first relapse in children with acute lymphoblastic leukemia 总被引:1,自引:0,他引:1
H Behrendt E F van Leeuwen C Schuwirth R J Verkes J Hermans A van der Does-van den Berg E R van Wering 《Cancer》1989,63(10):2066-2072
In a retrospective study, which comprised the whole Dutch childhood population of approximately 3 million children, the authors assessed the influence of an isolated meningeal relapse, occurring as first relapse, together with some patient and treatment characteristics on prognosis in 142 children with acute lymphoblastic leukemia (ALL). Until their first relapse, patients were initially treated according to standard protocols, whereas the treatment for relapse was heterogeneous. Concerning the probability of achieving a second complete remission (CR) it appears that the duration of the first CR is the single most important prognostic factor. The duration of the first CR is also the most important factor with regard to the duration of the second CR, upon which also age and sex have a significant influence. Concerning the survival from the time of central nervous system (CNS) relapse, again the duration of the first CR appears to be the most important prognostic factor, followed by age and the institution of systemic reinduction treatment. Other factors, such as initial leukocyte count, attainment of first CR within 48 days, type of reinduction treatment, and the cerebral spinal fluid (CSF) blast count at the time of relapse, have a less important, but nevertheless significant influence on survival. The median survival from the time of CNS relapse is 25 months, the 5-year survival is 25%, whereas the ultimate survival will be less than 20%. From 90 patients who developed second or subsequent relapses, 75% experienced a bone marrow relapse during the follow-up period. From this study the authors conclude that CNS relapse in children with ALL carries a grave prognosis, which requires the institution of intensive retreatment programs. 相似文献
985.
986.
Genetic ablation of the t-SNARE SNAP-25 distinguishes mechanisms of neuroexocytosis. 总被引:12,自引:0,他引:12
Philip Washbourne Peter M Thompson Mario Carta Edmar T Costa James R Mathews Guillermina Lopez-Benditó Zoltán Molnár Mark W Becher C Fernando Valenzuela L Donald Partridge Michael C Wilson 《Nature neuroscience》2002,5(1):19-26
Axon outgrowth during development and neurotransmitter release depends on exocytotic mechanisms, although what protein machinery is common to or differentiates these processes remains unclear. Here we show that the neural t-SNARE (target-membrane-associated-soluble N-ethylmaleimide fusion protein attachment protein (SNAP) receptor) SNAP-25 is not required for nerve growth or stimulus-independent neurotransmitter release, but is essential for evoked synaptic transmission at neuromuscular junctions and central synapses. These results demonstrate that the development of neurotransmission requires the recruitment of a specialized SNARE core complex to meet the demands of regulated exocytosis. 相似文献
987.
988.
Mari-Ann Flyvholm Barbara M. Hall Tove Agner Eva Tiedemann Peter Greenhill Walter Vanderveken Fred E. Freeberg Torkil Menné 《Contact dermatitis》1997,36(1):26-33
Our purpose was to investigate the eliciting threshold concentration of formaldehyde in formaldehyde-sensitive individuals in the occluded and non-occluded patch teat and to evaluate the relationship in repeated open application test (ROAT) with a product containing a formaldehyde releaser. 20 formaldehyde-sensitive patients and a control group of 20 healthy volunteer were included in the study. Occluded and non-occluded patch tests with formaldehyde solutions form 25 to 10,000 ppm. and ROAT for I week with a leave-on cosmetic product containing on average 300 ppm formaldehyde. Were carried out simultaneously on each subject. In the occluded patch test. 1/2 of the 20 patients only reacted to 10,000 ppm formaldehyde. 9 reacted to 5,000 ppm. 3 reacted to 1.000 ppm. 2 reacted to 500 ppm and I reacted to 25 ppm. No definite positive reactions were observed in the non-occluded patch test or in the ROAT No positive reactions were observed in the control group to any of the test procedures. We concluded that the threshold concentration for occluded patch test to formaldehyde in formaldehyde-sensitive patients was 250 ppm. The threshold in occluded patch test corresponded to the degree of sensitivity Definite positive reactions in the ROAT were not seen, either indicating that they are unlikely to happen with the type of product used or that the exposure time was too short. 相似文献
989.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献
990.
Mark F. Cotton Peter R. Donald Johan F. Schoeman Lana E. Van Zyl Cor Aalbers Carl J. Lombard 《Child's nervous system》1993,9(1):10-15
Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia. 相似文献