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151.
Hyaluronidase activity of human endometrial tissues and uterine fluids was investigated. Endometrial tissue and uterine fluid specimens were obtained from normal human subjects, and different cases of uterine dysfunction induced by steroidal contraceptives, copper IUD, lactational amenorrhea, and in early pregnancy. Hyaluronidase activity was found to increase from Cycle Days 8 to 10 and reach the maximum value during the secretory phase. Hyaluronidase activity was reduced in both endometrial tissue and uterine fluid during lactational amenorrhea and early pregnancy, and was drastically reduced in copper-IUD and steroidal contraceptive users. The low hyaluronidase activity in the early phase of the cycle may be due to rapid growth of endometrial tissue. In the secretory phase, the corresponding activities were found to increase because of high secretory activity and enhanced catabolic processes. In early pregnancy, the low lysosomal enzyme activity may also be explained on the basis of increased endometrium tissue growth. Low hyaluronidase activity of amenorrhic subjects may be due to the absence of ovarian steroids.  相似文献   
152.
A potential enzymic mechanism for the degradation of glycosaminogly cans was characterised using enzymes found in rheumatoid synovial fluid from the knee joint. This mechanism involves a true hyluronidase together with the concerted action of beta-glucuronidase and beta-N-acetylhexosaminidase. The contribution of the exopolysaccharidases to hyaluronate degradation was demonstrated by the use of specific inhibitors, while the distinct identity of a true hyaluronidase was shown by ammonium sulphate and agarose gel column fractionations. Only the hyluronidase fraction was capable of degrading high molecular weight hyaluronate. The exopolysaccharidase activities were shown to be markedly elevated in rheumatoid as compared to osteoarthritic synovial fluid and also normal serum. On the other hand, hyluronidase was similarly active in rheumatoid and osteoarthritic synovial fluids; both these levels were lower than that of normal human serum. Hyaluronidase in synovial fluid may thus be derived by diffusion from serum, since it is of relatively low molecular weight (60 000). The pH requirements of this enzyme system and the strong inhibition of hyaluronidase by synovial fluid make it unlikely that the mechanism operates extracellularly. It is proposed that as a lysosomal mechanism, however, it is an important contributing factor in the chronic erosion process characteristic of rheumatoid arthritis.  相似文献   
153.
Very low density and high density lipoproteins have been isolated from human plasma and their interaction with 1-anilin0-8-naphthalene sulfonate has been studied under different conditions of pH and added salt. Intrinsic fluorescence of bound 1-anilino-8-naphthalene sulfonate was higher for high density lipoproteins then for very low density lipoproteins, but was unaffected by salt in both systems. Binding of 1-anilino-8-naphthalene sulfonate by both these lipoproteins was saturable and was higher in the presence of added NaCl or CaCl2, Ca2+ having a greater effect than Na+ in enhancing fluorescence. The binding data were analyzed by Scatchard plots; the number of binding sites and the affinity of 1-anilino-8-naphthalene sulfonate for the site increased with increasing salt concentration. Fluorescence pH curves were similar to those published for phospholipids. From these and previous observations it is suggested that the phospholipids probably represent the major binding sites for 1-anilino-8-naphthalene sulfonate.  相似文献   
154.
The effect of 3-(3,4-dihydro-6-methoxy-2-naphthyl)-2,2-dimethyl-pentanoic acid, a potent nonsteroidal antifertility compound, on the uptake of estradiol-17beta-6, 7-tritiated in vitro in the rat uterus was studied. The estradiol uptake of estrogen-primed and compound-treated groups were the same. When estradiol and the compound were present in medium at the same time, estradiol uptake was significantly (p less than .01) increased. The results indicate that the compound synergizes the effect of estradiol.  相似文献   
155.
Two locally-produced seasonal vegetables, carrot and patol, were preserved in brine, with and without radiation, with marked changes in their properties as foods and their microbiology. The treated vegetables could be preserved, at optimum salt and irradiation levels, for up to 60 days without becoming unacceptable in terms of appearance, texture, flavour and taste. The optimum salt concentrations for preservation of carrot and patol were 2% (w/v) and 3% (w/v), respectively. The microbial load initially showed an upward trend and then declined after 5 to 10 days of storage. Lactic acid bacteria predominated in treated vegetables.  相似文献   
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158.
The lipopolysaccharide isolated from the cells of Shigella boydii type 8 bacteria gave precipitin bands against homologous antisera on Ouchterlony plates, whereas the carbohydrate-containing fractions obtained from it did not. One of the fractions was obtained in major proportion and contained 23.5% of sugars. A structure was assigned to the carbohydrate chain in this material by using the results of methylation, periodate oxidation, and deamination studies.  相似文献   
159.
160.
Summary The Gymnoascaceae have long been regarded by many as the perfect stages of certain imperfect dermatophytic fungi. In recent years increasing numbers of reports have been published in which the Gymnosacaceae have been isolated from pathological conditions and have often been regarded as at least potential pathogens. This paper reviews previous reports and presents certain new isolation data which should lead to a better understanding and appreciation of the role of these fungi in clinical investigations. Evidence supporting pathogencity of the Gymnoascaceae is suggestive but inconclusive.
Zusammenfassung Manche Verfasser haben die Gymnoascaceae schon lange als die perfekten Formen von gewissen imperfekten Dermatophyten betrachtet. In den letzten Jahren ist eine wachsende Anzahl von Berichten veröffentlich worden bezüglich Gymnoascaceae, die vom pathologischen Material gezüchtet und mindestens als bedingt pathogen betrachtet worden sind. Dieser Bericht gibt eine Übersicht von früheren Befunden und bringt manche neuen Tatsachen von neuen Isolationen. Sie sollen zu einem besseren Verständnis und zu einer besseren Auswertung der Rolle dieser Hyphomyceten in der klinischen Untersuchung führen. Die Beweise betreffs der Pathogenität der Gymnoascaceae sind lediglich mutmasslich und nicht konklusiv.
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