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991.
Possible role of mycobacteria in inflammatory bowel disease 总被引:32,自引:0,他引:32
Dr. Rodrick J. Chiodini PhD Herbert J. Van Kruiningen DVM PhD Walter R. Thayer MD Richard S. Merkal PhD Jessica A. Coutu BA 《Digestive diseases and sciences》1984,29(12):1073-1079
A previously unrecognizedMycobacterium species was isolated from two patients with Crohn's disease. The organism is an acid-fast, mycobactin-dependentMycobacterium that has characteristics which do not conform to any of the presently recognized species. It belongs to the Runyon group III mycobacteria and is most closely related toMycobacterium paratuberculosis. Animal inoculation revealed pathogenicity for mice when injected intravenously or intraperitoneally, but not for rats, guinea pigs, rabbits, or chickens. The mice developed hepatic and splenic granulomas which contained numerous acid-fast mycobacteria. A 7-day-old goat which was inoculated orally with 50 mg of the organism developed both humoral and cell-mediated immunologic responses in two to three weeks and granulomatous disease of the distal small intestine, with noncaseating tuberculoid granulomas in five months. Acid-fast bacilli were not demonstrable in sections of the intestine, but a single organism was seen in each of two microgranulomas of the mesenteric lymph node. TheMycobacterium species was reisolated from the lymph node but not from intestine. Our findings raise the possibility that aMycobacterium plays an etiologic role in at least some cases of Crohn's disease.Supported by a grant from the National Foundation for Ileitis and Colitis Inc. 相似文献
992.
993.
Effects of dihydropyridine calcium channel blocking drugs on rat brain muscarinic and alpha-adrenergic receptors 总被引:3,自引:0,他引:3
The dihydropyridine (DHP) Ca2+ channel blocking drugs nicardipine, nitrendipine, nimodipine, felodipine, nifedipine and nisoldipine were examined for activity in inhibiting specific (-)-[3H] QNB and [3H]WB4101 binding to the muscarinic and alpha-adrenergic receptors, respectively, of rat brain. Muscarinic receptor binding was affected most by nicardipine, with felodipine having less activity; the other DHP drugs were essentially inactive at 3 X 10(-5) M. The (+)-stereoisomer nicardipine (KI = 4.07 X 10(-7) M) was 27 times more potent than the (-)-isomer in inhibiting [3H]QNB binding, and this inhibition was found to be competitive. This inhibitory effect of nicardipine was not mediated via interaction with the high-affinity DHP binding site assumed to be associated with a Ca2+ channel. (+)-Nicardipine inhibited the binding of [3H]nitrendipine to this DHP binding site of brain, with a K1 of 9.01 X 10(-11) M, and was 10 times more potent than the (-)-isomer. Thus, the muscarinic receptor was 4200 times less sensitive to (+)-nicardipine than was this DHP binding site. Nicardipine was also the most potent DHP drug inhibiting [3H]WB4104 binding to the alpha-adrenergic receptor, although the other drugs were also somewhat active, in the rank order sequence listed above. This effect of nicardipine on the adrenergic receptor was also stereoselective, with (+)-nicardipine (KI = 3.46 X 10(-7) M) being about 3 times more potent than the (-)-isomer, in producing competitive inhibition of radioligand binding. These data suggest that the effects on brain receptors occur as a result of direct, stereospecific effects of DHP drugs on these receptors and are not due to Ca2+ channel blocking activity of these drugs. 相似文献
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996.
Maternally acquired immunity in newborns from women infected by the human immunodeficiency virus 总被引:2,自引:0,他引:2
MI de Moraes-Pinto CK Farhat SB Carbonare SP Curti MES Otsubo DS Lazarotti RC Campagnoli MMS Carneiro-Sampaio 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S385):1034-1038
Maternally acquired immunity was studied in 16 pairs of human immunodeficiency virus (H1V)-seropositive women and their newborns, and was compared to 18 control mother-newborn pairs. The HIV-infected women had higher IgG levels than the control subjects, but no difference was observed between newborn samples, presumably due to the limited placental IgC transfer in the HIV group. A poor type 2 poliovirus antibody transfer was also noted in this group. The population of newborns lacking demonstrable measles antibodies was higher in the HIV group than in the control group, probably because many of the HIV-infected mothers lacked measles antibodies also. These results show that maternally acquired immunity may be affected to newborns from HIV-infected women, either because of low maternal serum antibody levels or deficient transplacental transfer. If so, the measles vaccine schedule should be revised for these children and the same should be done for future passive immunization regarding fetus protection in pregnant HIV-seropositive women. 相似文献
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998.
山茱萸化学成分的研究 总被引:31,自引:1,他引:30
从山茱萸(Cornus officinalis Sieb.et Zucc.)的果实中分得一新的双环烯醚萜甙化合物,命名为山茱萸新甙(cornuside)。通过波谱分析(IR,MS,1HNMR和13CNMR)和理化常数测定,确定了它的结构。 相似文献
999.
C A Presant B Ardalan P Multhauf C Chan R Staples L Green S Browning B I Carr F F Chang W Thayer 《Medical and pediatric oncology》1983,11(3):162-163
In order to determine whether a simultaneous infusion of N-(phospho-n-acetyl)-L-aspartic acid (PALA) was able to increase the rate of antitumor response to 5-fluorouracil (5-FU), a pilot study was conducted. Of 10 evaluable patients with previously drug-untreated colorectal carcinoma, there were only two partial responses, lasting 2.3 and 1.6 months. No partial responses were observed in three evaluable patients with soft tissue sarcomas. The dose-limiting toxicity was dermatitis. The simultaneous infusion of PALA and 5-FU is not likely to produce a high number of antitumor responses of long duration in patients with colorectal carcinoma. 相似文献
1000.