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981.
982.
An unusual case of neurofibrosarcoma of the cranio-orbital-maxillary region was resected by a combined neurosurgical and plastic surgical team. The resulting defect was reconstructed in one stage with a free rectus abdominis myocutaneous flap, obviating the need for subsequent prosthetic obturation of the maxillary defect. This reconstructive technique expedited the patient's convalescent period, allowing him to return to work 3 weeks following surgery. Wound healing was uneventful, and the cosmetic result was acceptable to the patient. 相似文献
983.
Aspartate, glutamate, or dicarboxylic acids did not inhibit the activity of a highly purified but not homogeneous preparation of pyruvate carboxylase fromThiobacillus novellus. The only effective inhibitors were end-products of the reaction and to a lesser degree hydroxypyruvate. The latter has not been shown previously to regulate the enzyme's activity. Lineweaver-Burk plots revealed that it was uncompetitive with respect to acetyl CoA with a Kii of 3.6 mM, and noncompetitive with respect to bicarbonate, magnesium ATP, and pyruvate with respective Kii values of 7.1, 5.5, and 6.47 mM. The corresponding Kis values were 7.02, 5.4, and 4.25 mM. A mathematical model is presented that supports the findings. 相似文献
984.
Murine retrovirus-induced spongiform encephalomyelopathy: host and viral factors which determine the length of the incubation period. 下载免费PDF全文
A molecular clone of wild mouse ecotropic retrovirus CasBrE (clone 15-1) causes a spongiform neurodegenerative disease with a long incubation period, greater than or equal to 6 months. This virus infects the central nervous system (CNS) at low levels. In contrast, a chimeric virus, FrCasE, containing env and 3' pol sequences of 15-1 in a Friend murine leukemia virus background, infects the CNS at high levels and causes a rapid neurodegenerative disease with an incubation period of only 16 days. With both viruses, the induction of neurologic disease is dependent on inoculation during the perinatal period. Since the length of the incubation period of this disease appears to be a function of the relative level of CNS infection, we have attempted to identify the viral and host factors which determine the relative level of virus infection of the CNS. It was previously shown that the CNS is susceptible to infection only during the perinatal period (M. Czub, S. Czub, F. J. McAtee, and J. L. Portis, J. Virol. 65:2539-2544, 1991). Here we have found that the susceptibility of the CNS wanes progressively or gradually as a function of the age of the host, this age-dependent resistance being complete by 12 to 14 days of age. Utilizing a group of chimeric viruses, we found that the relative level of CNS infection achieved after inoculation of mice at 1 day of age was a function of the kinetics of virus replication and spread in peripheral organs. Viruses which reached peak viremia titers early (5 to 7 days of age) infected the CNS at high levels, and viruses which reached peak titers later infected the CNS at lower levels. Among the group of viruses examined in the current study, the kinetics of peripheral virus replication and spread appeared to be influenced primarily by sequences within the R-U5-5' leader region of the viral genome. These results suggested that the relative level of CNS infection was determined very early in life and appeared to be a function of a dynamic balance between the kinetics of virus replication in the periphery and a progressively developing restriction of virus replication in the CNS. 相似文献
985.
Ronald L. Rutowski 《Animal behaviour》1982,30(1):108-112
Free-flying males of the checkered white butterfly, Pieris protodice, were presented with tethered females that varied with respect to both size (as measured by forewing length) and age (as measured by wing wear). Because males make a substantial investment in their offspring through nutrients passed to the female during copulation, they were expected to court young and large females for longer times than older and smaller females, and they did so. Additional experiments further suggest that size discriminations are made on the basis of apparent wing area and age discriminations are made on the basis of an age-related increase in ultraviolet reflectance that occurs in females. The discussion examines the adaptive value of these discriminations. 相似文献
986.
987.
D. L. Levene 《CMAJ》1973,108(12):1480-passim
988.
L M Luxon 《BMJ (Clinical research ed.)》1993,306(6891):1490-1491
989.
990.
Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献