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971.
972.
973.
The glycogen content of endometrial biopsy specimens obtained from 10 normally menstruating women was measured in the proliferative and in the secretory phase of the menstrual cycle. These measurements were repeated following 5–14 cycles with the Cu-T device in situ. In five of the ten subjects studied, the endometrial glycogen content was also estimated during the first to fourth cycles with the device in situ.

The glycogen content of the secretory endometrium was significantly higher than that of the proliferative endometrium both in the absence and in the presence of the device. The use of the Cu-T device for more than 5 cycles resulted in a significant increase in the glycogen content of the endometrium both in the proliferative and in the secretory phase. No such increase was found following a relatively short-term use of the device (1–4 cycles).

It is concluded that the prolonged use of the Cu-T device results in a marked accumulation of glycogen in the human endometrium.  相似文献   

974.
Zusammenfassung Es wird ein kurzer Überblick über die bei achondrodysplastischen Zwergen vorkommenden Wirbelsäulenveränderungen gegeben. Die häufig neurologischen Ausfälle beruhen in der Regel auf einer Kompression des Rückenmarkes und/oder der Cauda equina in dem verengten Wirbelkanal.Beschreibung eines eigenen Falles, bei dem das Bild einer Pseudo-Claudicatio intermittens durch eine abnorme Elongation der Kaudafasern um etwa 8 cm verursacht war. Nach operativer Dekompression bildeten sich die Störungen und Beschwerden zurück.
Summary A short review is presented of the spinal column changes which occur in achondroplastic dwarfs. The chief neurological results are, as a rule, due to compression of the spinal cord and/or of the cauda equina in the narrowed spinal canal.A personal case is described in whom the picture of intermittentpseudo-claudication was caused by an abnormal elongation of about 8 cm of the cauda equina roots. After decompressive operation the symptoms and signs regressed.

Resumen El autor presenta un estudio de las modificaciones del raquis en los enanos acondroplásticos. Los signos neurológicos importantes están por lo general unidos a la compresión de la medula o de la cola de caballo en el canal espinal.En una observación personal la pseudoclaudicación intermitente estaba en relación con una elogación anormal, de 8 cms., de las raices de la cola de caballo. Después de una operación descompresiva los síntomas regresaron.

Résumé L'auteur présente une étude des modifications du rachis chez les nains achondroplastiques. Les signes neurologiques importants sont en règle liés à la compression de la moelle ou de la queue de cheval dans l'étroit canal spinal.Dans une observation personnelle, la pseudo claudication intermittente était liée à une élongation anormale de 8 cm des racines de la queue de cheval. Après une intervention décompressive les symptômes ont régressé.

Riassunto Gli AA. fanno una breve esposizione delle modificazioni delle colonna vertebrale che si riscontrano nel nanismo acondroplasico.Le frequenti alterazioni neurologiche sono determinate di regola da una compressione del midollo spinale e/o delle cauda equina nel canale vertebrale ristretto.Gli AA. descrivono un caso personale, nel quale il quadro di una pseudoclaudicatio intermittens era causato da un allungamento delle fibre delle cauda di circa 8 cm.In seguito a decompressione operatoria i disturbi ed i dolori scomparvero.
  相似文献   
975.
976.
We describe an outbreak of necrotizing enterocolitis (NEC) that occurred in the neonatal intensive care unit of our hospital. A total of 12 neonates developed NEC in June-July 1998. For two of them, twin brothers, the NEC turned out to be fatal. Enterobacter sakazakii, a known contaminant of powdered milk formula, was isolated from a stomach aspirate, anal swab, and/or blood sample for 6 of the 12 neonates. A review of feeding procedures revealed that 10 of the 12 patients were fed orally with the same brand of powdered milk formula. E. sakazakii was isolated from the implicated prepared formula milk as well as from several unopened cans of a single batch. Molecular typing by arbitrarily primed PCR (AP-PCR) confirmed, although partially, strain similarity between milk and patient isolates. No further cases of NEC were observed after the use of the contaminated milk formula was stopped. With this outbreak we show that intrinsic microbiological contamination of powdered milk formula can be a possible contributive factor in the development of NEC, a condition encountered almost exclusively in formula-fed premature infants. The use of sterilized liquid milk formula in neonatal care could prevent problems with intrinsic and extrinsic contamination of powdered milk formula.  相似文献   
977.
Comparison of spontaneous mutation spectra derived from different transgenic constructs can provide valuable insights for interpreting the mechanisms of spontaneous mutation. In this study, spontaneous mutation frequencies and spectra of the lacI transgene are compared in the liver of C57BL/6, B6C3F1, and BC-1 mice and F344 rats. Before correction for clonal expansion, the mutant frequency varied from 2.6 +/- 0.45 to 5.0 +/- 2.4 x 10(-5). Correction for potential clonal expansion reduced the range in mutation frequency to between 2.3 +/- 0.45 and 3.5 +/- 2.0 x 10(-5). There is thus no statistical difference in spontaneous mutation frequency between the different strains and species. G:C --> A:T transitions and to a lesser extent, G:C --> T:A transversions dominate the mutational spectra in all of these animals. In three strains of mice, G:C --> A:T transitions account for 50.7-53.3% of mutation, 81.7-83.8% of which involve CpG sites, whereas G:C --> T:A transversions account for 17.8-32.9% of mutations with 43.2-50.0% found at CpG sites. In rats, G:C --> A:T transitions account for 38.0% of the spectra, 70.0% of which involve CpG sites, whereas G:C --> T:A transversions account for 23.0% of the spectra, 70.0% of which involve CpG sites. The distribution of other classes of mutations is also very similar. We conclude that, despite reports about species and strain differences in induced mutation, spontaneous mutations in the lacI transgene appear to be similar, regardless of genomic location, rodent strain, or species. In addition to insights into spontaneous mutation, this study also provides essential data for comparison with and interpretation of induced mutations.  相似文献   
978.
The author gives a synthesis of original and specific characteristics of inter-tropical zones, abiotic (climate, soils) and especially biotic data: biodiversity originality, adaptations, ecosystems. He concludes his review by considering the richness of biological interactions (with two or three partners) as well as the biotic systems with parasites and hosts and the struggle against parasites of ecological (via bioindication) or biological nature.  相似文献   
979.
Recent studies have suggested the use of lipoproteins as an adjuvant treatment of lethal gram-negative infections. However, other important microorganisms for the etiology of sepsis, such as Candida species, grow better in lipid-rich environments. We investigated the effect of hyperlipoproteinemia on systemic candidiasis in low-density-lipoprotein-receptor-deficient (LDLR-/-) mice, in which the loss of the receptor results in a seven- to ninefold-higher plasma LDL level than that in their wild-type littermates (C57BL/6J). LDLR-/- mice died earlier, and the outgrowth of Candida albicans in the kidneys and livers of LDLR-/- mice was significantly higher compared with that of controls. After infection, circulating cytokine concentrations were significantly higher in LDLR-/- mice. In vitro, C. albicans grew better in plasma samples of LDLR-/- mice than in control plasma samples and peritoneal macrophages of LDLR-/- mice challenged with heat-killed C. albicans produced more cytokines than did those of controls. This latter phenomenon was probably due to increased binding of yeast cells to macrophages of LDLR-/- mice. These data suggest that hyperlipoproteinemia is deleterious in systemic candidiasis.  相似文献   
980.
Trypanosoma cruzi (epimastigotes), Crithidia fasciculata and Leishmania mexicana (promastigotes) were grown in a brain-heart-tryptose medium supplemented with heat-inactivated fetal calf serum. T. cruzi and C. fasciculata utilized glucose completely during the log phase of growth, whereas L. mexicana used significant amounts of the carbohydrate only at the end of the log phase and at the beginning of the stationary phase. In all cases glucose consumption resulted in excretion of succinate, and much smaller amounts of acetate. C. fasciculata and L. mexicana produced very small amounts of pyruvate. C. fasciculata produced ethanol, which was taken up again and metabolysed after glucose was exhausted. Lactate and malate were not produced. The cells were disrupted by sonic disintegration, and the activities of some key enzymes of carbohydrate and amino acid catabolism were assayed in the whole homogenates. Phosphoenolpyruvate carboxykinase was present in the three organisms; L. mexicana presented the highest specific activity. The activity of this enzyme was maximal during glucose consumption, and slightly decreased after glucose was exhausted. This suggests that the role played by the enzyme is glycolytic and not gluconeogenic; the latter is the case in most higher organisms. Hexokinase and pyruvate kinase presented their highest levels in C. fasciculata and T. cruzi during glucose consumption. L. mexicana, which was in active glycolysis during the whole experimental period, presented the highest specific activities of both enzymes. Citrate synthase, on the other hand, increased in C. fasciculata and, to a lesser extent, in T. cruzi, after glucose was exhausted; the enzyme could not be detected in L. mexicana. The NAD-linked glutamate dehydrogenase increased considerably in C. fasciculata and T. cruzi after glucose was exhausted, suggesting a catabolic role for the enzyme. This increase coincided with an increase in NH3 production by both organisms after glucose consumption. The NADP-linked glutamate dehydrogenase, on the other hand, presented a maximum about the time when glucose was exhausted, and then decreased again, which suggests a catabolic role for the enzyme. Both glutamate dehydrogenases had low activities in L. mexicana; this fits in well with the low NH3 production throughout the culture of this organism. The results are in good agreement with current ideas on the mechanism of aerobic glucose fermentation by trypanosomatids, and suggest that, under the experimental conditions used, both T. cruzi and C. fasciculata used glucose perferentially over amino acids for growth.  相似文献   
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