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51.
Michael M. Vanyukov Howard B. Moss Anthony E. Gioio Hugh B. Hughes Barry B. Kaplan Ralph E. Tarter 《Behavior genetics》1998,28(2):75-82
We have conducted a population-based association study of substance abuse and a microsatellite at the dopamine D5 receptor locus (DRD5) in a sample of European–American males and females with substance dependence (SA) or without any psychiatric disorder. Overrepresentation of the most frequent allele (148 bp) was found in males in the SA group (OR = 2.2, P= .02); this finding was reproduced in females (OR = 5.4, p< .001). The difference in the frequencies of this allele between SA males and SA females was statistically significant. The genotype coded in accordance with the dose of this allele correlated with substance abuse liability in males and females (stronger in females) and with novelty seeking in females. There was no evidence of correlation between the genotypes of spouses that could be induced by assortative mating for the liability to substance abuse. The data suggest that the DRD5 locus is involved in the variation and sex dimorphism of substance abuse liability.CEDAR is a consortium between St. Francis Medical Center and the University of Pittsburgh. 相似文献
52.
C Moss S Larkins M Stacey A Blight P A Farndon E V Davison 《Journal of medical genetics》1993,30(9):752-755
To test the hypothesis that epidermal rather than dermal mosaicism determines Blaschko's lines in hypomelanosis of Ito (HI), we studied the distribution of chromosomal mosaicism in four patients. In two, mosaicism had not been detected in lymphocytes or dermal fibroblasts, but was clearly shown in epidermal keratinocytes; furthermore, the abnormal cell line was confirmed to the hypopigmented epidermis and the normal epidermis contained only normal cells. Negative findings in the other two patients might be because of mosaicism which was undetected either because it was submicroscopic or because it was present in melanocytes, which have not yet been studied. These preliminary results support the ideas that (1) Blaschko's lines represent single clones of epidermal cells; (2) in patients with HI and severe neurological involvement mosaicism, if detectable, is best shown in keratinocytes; and (3) the cytogenetic defect in epidermal cells may be directly responsible for the failure of pigmentation in HI. 相似文献
53.
M. A. Livesley S. E. Tebbs H. A. Moss M. H. Faroqui P. A. Lambert T. S. J. Elliott 《European journal of clinical microbiology & infectious diseases》1998,17(2):108-112
Microorganisms detected in situ on the distal tip of central venous catheters (CVC) within 90 min of insertion were investigated using pulsed-field gel electrophoresis to analyse genomic fragments obtained with theSmaI restriction enzyme. Thirty patients received a triple lumen CVC, which was inserted directly through the skin using the Seldinger technique. In a further 30 patients a triple lumen CVC was inserted through a Swan sheath, thereby avoiding direct contact of the CVC with the skin. Staphylococci were isolated from the distal tips of the catheters in 6 patients (5 who had the CVC inserted directly through the skin and 1 who had the CVC inserted via a Swan sheath.) Twenty-three staphylococcal isolates were also isolated from the insertion equipment and the skin swabs surrounding the insertion site of these six patients. All the isolates were genotyped. In one of the patients the organisms isolated from the skin were identical to those on the CVC tip. In two further patients similar organisms were isolated from the insertion equipment and the patients' skin. These results, in addition to the reduced colonisation rates observed when catheters were introduced through a Swan sheath, support the hypothesis that microorganisms from the skin are impacted onto the CVC tip and the CVC insertion equipment at catheter insertion. 相似文献
54.
Inhibition of vaccinia virus late protein synthesis by isatin-beta-thiosemicarbazone: characterization and in vitro translation of viral mRNA. 总被引:4,自引:0,他引:4
Thespecific effect of istin-βthiosemicarbozone (IBT) was manifested after vaccinia virus late protein synthesis had commenced. At 6 hr after infection, viral protein synthesis was inhibited by about 9596. We confirmed that λ portion of the virus-specific RNA appears to be degraded (B. Woodson and W. K. Joklik, 1965, Proc. Nat. Acad. Sci. USA 54,946–953). Nevertheless, the amount of viral RNA that was capped, properly methylated, and polyadenylylated, was reduced by only about 50%. Moreover, RNA from IBT-treated cells stimulated cell-free protein synthesis to one-half the level obtained with RNA from control cells. Polyacrylamide gel electrophoretic analysis further demonstrated that RNA from IBT-treated cells was translated into late viral proteins in vitro. Thus, it seems possible that the inhibition of protein synthesis in IBT-treated cells does not result entirely or directly from either an inhibition of mRNA synthesis or from λ depletion of mRNA caused by accelerated degradation. An alternative possibility, that accelerated degradation is secondary to λ more immediate effect of the drug on protein synthesis, was considered. 相似文献
55.
30 years of campylobacters: biochemical characteristics and a biotyping proposal for Campylobacter jejuni. 总被引:14,自引:20,他引:14 下载免费PDF全文
G A Hbert D G Hollis R E Weaver M A Lambert M J Blaser C W Moss 《Journal of clinical microbiology》1982,15(6):1065-1073
Several biochemical test systems were studied for their potential usefulness for the examination of strains of Campylobacter species. Most (81%) of the C. jejuni strains hydrolyzed sodium hippurate, but strains of C. fetus, C. sputorum, and C. fecalis did not. Some (46%) of the C. jejuni strains and all of the C. sputorum subsp. sputorum, C. sputorum subsp. bubulus, and C. fecalis strains hydrolyzed DNA, but the C. fetus and C. sputorum subsp. mucosalis strains did not. Strains of all species of Campylobacter grew on charcoal-yeast extract agar, but 47% of the C. jejuni strains did not. Alkaline phosphatase activity was recorded for some strains of C. jejuni, but all other species were negative for this activity. Aryl sulfatase activity was detected in 7% of the C. jejuni, 15% of the C. fetus subsp. fetus, and all of the C. sputorum subsp. sputorum, C. sputorum subsp. bubulus, and C. fecalis strains, but it was not detected in the C. fetus subsp. venerealis and C. sputorum subsp. mucosalis strains. Most (93%) of the C. jejuni but none of the other Campylobacter strains contained lactobacillic acid when examined for cellular fatty acids. On the basis of results from three of these tests (hippurate hydrolysis, DNA hydrolysis, and growth on charcoal-yeast extract agar), clinical strains of C. jejuni were placed in eight biotypes. 相似文献
56.
57.
Comparison of biochemical, morphologic, and chemical characteristics of Centers for Disease Control fermentative coryneform groups 1, 2, and A-4. 总被引:3,自引:2,他引:3 下载免费PDF全文
A total of 24 strains of fermentative coryneform like bacteria isolated from clinical specimens form two distinct groups which have been designated Centers for Disease Control (CDC) fermentative coryneform groups 1 (13 strains) and 2 (11 strains). The phenotypic characteristics of group 1 were similar to those of a previously described CDC group designated A-4, with the major differentiating characteristic being the inability to hydrolyze esculin. Major differences in cellular fatty acid composition between CDC groups 1 and A-4 were also observed. The branched-chain fatty acids 14-methylhexadecanoate and 12-methyltetradecanoate, which account for more than 80% of the total acids of group A-4, were not detected in cells of group 1 strains. Groups 1 and 2, which have similar cellular fatty acid compositions, can be differentiated on the basis of fermentation of xylose, mannitol, lactose, sucrose, and melibiose by group 1 but not by group 2. The sources of isolation of the strains of both groups varied. Only group 1 strains were associated with eye infections. 相似文献
58.
Alison Severn Damo Xu Jacqueline Doyle Ludmila M. C. Leal Catherine A. O'Donnell Sara J. Brett David W. Moss Foo Y. Liew 《European journal of immunology》1993,23(7):1711-1714
Murine macrophages produce nitric oxide (NO) from L-arginine on stimulation with lipopolysaccharide (LPS), alone or with interferon-γ (IFN-γ). The effect of incubation of macrophages with low concentrations of LPS on NO synthesis on subsequent stimulation was investigated, using a murine macrophage cell line, J774, and peritoneal macrophages from CBA mice. Cells which had been incubated with LPS produced significantly lower amounts of NO, and expressed lower levels of NO synthase activity, following stimulation with IFN-γ and LPS, or with a high concentration of LPS. This effect was not reversed by tumor necrosis factor-α. The ability of CBA macrophages to kill the intracellular parasite Leishmania major was markedly reduced by pre-incubation with LPS. Reduced NO production by macrophages previously exposed to LPS is a manifestation of endotoxin tolerance, and may represent an important means of regulation of NO synthesis and thus a survival mechanism for intracellular parasites. 相似文献
59.
M. C. Barrett S. J. Cashman J. Moss 《International journal of experimental pathology》1983,64(4):425-436
The nephrotoxic properties of the chemical N-(3,5-dichlorophenyl)-succinimide were investigated in rats with a view to establishing the usefulness of this chemically-induced nephritis as a model of chronic interstitial renal fibrosis. The compound was synthesized and given daily by gastric intubation as a suspension in arachis oil B.P. to male WAG-strain rats, for periods of up to 108 days. Polydipsia and polyuria resulted rapidly in all treated animals and persisted for the duration of the experiment. There was a progressive increase in the extent of proteinuria in all treated animals and, by the end of the experiment, there was an increase in the plasma levels of urea and creatinine. Short term treatment (up to 3 days) resulted in focal areas of necrosis of some proximal convoluted tubules. Treatment for 28 days resulted in patchy but severe tubular interstitial nephritis with which was associated a moderate interstitial fibrosis. By 108 days, the nephritis was more widespread and the interstitial fibrosis was severe. The activity of proline hydroxylase, a part of the intracellular sequence of collagen synthesis, showed progressive increase in the renal cortex throughout the experiment and there was an associated increase in the cortical hydroxyproline content, a measure of the amount of collagen present. Associated with this biochemical evidence of an active, chronic fibrosis, was an increased water content of the cortical tissue. The results indicate that this chemically-induced, tubular interstitial nephritis is indeed a good and reliable model of interstitial renal fibrosis. 相似文献
60.
Richard Cooper Ivan Soltero Jeremiah Stamler Louise Mojonnier Yolanda Hall Dorothy Moss David M. Berkson Tom Tokich 《Journal of the National Medical Association》1982,74(4):349-355
Quit-rates for cigarette smokers in a lifestyle intervention program aimed at reducing coronary risk were 24 percent for all participants and 34 percent for non-dropouts. Recidivism remained very low during participation in the program. Half of the smokers who quit did so after being in the program more than two years. These data suggest that while engaging in an effort to make other changes in lifestyle, many smokers can be helped to quit. Sustained antismoking efforts in the clinical practice of medicine can be expected to share these same positive aspects. While mass public health programs to eliminate smoking and prevent young people from taking up the habit are being developed, health practitioners can make a significant contribution by including vigorous efforts at smoking cessation as part of routine practice. 相似文献