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21.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
22.
National Salmonella & Escherichia Centre situated at Central Research Institute, Kasauli receives Salmonella strains from all over the country. Eight hundred and fourteen Salmonella strains belonging to 14 serotypes received during 1986 were studied for antibiotic resistance and Minimum Inhibitory concentration (MIC) with regard to ampicillin (A), chloramphenicol (C), furazolidone (Fz) and gentamicin (G). Resistance to ampicillin was found to be highest (80%) and furazolidone the least (0.1%). Similarly a large number of strains (31%) had very high MIC values greater than 640 mcg per ml for chloramphenicol, whereas only 3.4% strains were found to have MIC values greater than 640 mcg per ml for gentamicin. The present findings have been discussed in the light of similar data published from this Centre earlier and from other sources in India. 相似文献
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24.
Antoinette MaassenVanDenBrink MSc ; Monique N. Vergouwe MSc ; Roel A. Ophoff PhD ; Pramod R. Saxena MD PhD ; Michel D. Ferrari MD PhD ; Rune R. Frants PhD 《Headache》1998,38(4):288-291
The 5-HT1 receptor agonist, sumatriptan, is highly effective in the treatment of migraine. Some patients, however, do not respond or experience recurrence of the headache. In addition, some patients report chest symptoms after sumatriptan. We investigated whether these different responses could be attributed to genetic diversity of the 5-HT1B receptor, which most likely mediates the therapeutic action and the coronary side effects of sumatriptan. Allele frequencies of two polymorphisms in the 5-HT1B receptor gene ( G861C and T-261G ) were investigated in migraine patients with consistently good response to sumatriptan (n=14), with no response (n=12), with recurrence of the headache (n=12), with chest symptoms (n=13), and in patients without chest symptoms (n=27). Allele frequencies (G:0.74; C:0.26 at nt 861 and T:0.39; G:0.61 at nt -261) did not differ between patient groups, indicating that genetic diversity of the 5-HT1B receptor does not seem to be involved in the different clinical responses to sumatriptan. 相似文献
25.
Adsorption and movement of carbofuran (a systemic nematicide) were studied using two Indian soils (clay loam and silt loam) of alluvial origin. Equilibrium adsorption coefficient (K) values measured using a batch-slurry technique follows the order clay loam greater than silt loam soil. The distribution coefficients (Kd) for both the soils in batch adsorption as well as in columns were also calculated. Carbofuran movement in soil columns during water infiltration in both air-dried and water-saturated columns was estimated. The order was as anticipated from K and Kd values. A larger amount of water was needed for leaching the carbofuran to 152 cm in clay loam soil than in silt loam soil. Carbofuran appears to increase in drier soils and in finer textured soils. 相似文献
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Recently, AG-25086 and GR-43175 have been reported to be highly effective in aborting acute migraine attacks. These compounds seem selectively to stimulate a sub-population of 5-HT(1)-like receptors to inhibit noradrenaline release from certain sympathetic neurovascular terminals, to contract dog saphenous vein and dog, monkey and human basilar arteries, and to decrease the arteriovenous anastomotic component of carotid blood flow in the cat. GR-43175 neither has any antinociceptive effect nor crosses the blood-brain barrier. Pramod Saxena and Michel Ferrari review the clinical effectiveness of these 5-HT(1)-like receptor agonists and their selective pharmacology, both of which strongly suggest that excessive dilatation in the extracerebral cranial (scalp and/or dural) vasculature is an integral part of the pathophysiology of migraine. 相似文献
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Mannan composition of the hyphal form of two relatively avirulent mutants of Candida albicans. 总被引:1,自引:2,他引:1 下载免费PDF全文
We have previously reported the characteristics of mannans isolated from the yeast forms of two relatively avirulent Candida albicans strains, designated 4918-2 and 4918-10. Investigations have been expanded to include an analysis of mannans from the hyphal form of these strains as well as from the hyphal form of the parental strain, 4918. After extraction, mannans were further purified by high-pressure liquid chromatography on a Bio-gel TSK DEAE-5-PW column. Subsequent to either mild acid hydrolysis, alkali hydrolysis, or acetylation followed by acetolysis, the resulting products were fractionated by high-pressure liquid chromatography on an Aminex HPX-42A column. The results of acid hydrolysis showed only minor quantitative differences in the products released from each strain, with mannose constituting the vast majority of product liberated. The profiles of mannooligosaccharides obtained from either alkali hydrolysis or acetolysis for strain 4918-2 showed distinct quantitative differences compared with profiles of the other two strains. Finally, a general characteristic noted is a decrease in the average chain length of mannooligosaccharides in hyphal mannans compared with the yeast counterpart. 相似文献
30.
Tandon A Singh A Atrishi E Saxena SK Mathur A 《International journal of experimental pathology》2002,83(1):39-46
A unique factor, human T cell hypoglycaemic factor (hTCHF), has been shown to produce hypoglycaemia during the convalescent stage in the plasma of patients with Japanese encephalitis virus (JEV) infection. The present study was undertaken to investigate the ability of T cells from fresh peripheral blood mononuclear cells (PBMC) of such patients to produce hTCHF. The PBMC, as well as the individual subpopulations, were cultured for 24 h and the culture supernatants (CS) were assayed for hypoglycaemic activity. The activity was observed in the CD8+ T cells. The hypoglycaemia in JE-confirmed patients coincided with the gradual rise in circulating glucagon level, with no significant alterations in insulin, growth hormone and cortisol levels. The hTCHF was purified by ion exchange chromatography and the purified protein was observed as a approximately 25 kDa band on SDS-PAGE. Secretory hTCHF in the sera of patients and T cell CS was present in 88% of convalescent serum samples. We conclude that during the convalescent stage of JEV infection, a unique factor, hTCHF, is secreted by activated CD8+ T cells from patients and that this is responsible for the development of hypoglycaemia. 相似文献