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991.
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Joellen M Schildkraut Susan K Murphy Rachel T Palmieri Edwin Iversen Patricia G Moorman Zhiqing Huang Susan Halabi Brian Calingaert Alison Gusberg Jeffrey R Marks Andrew Berchuck 《Cancer epidemiology, biomarkers & prevention》2007,16(3):473-480
INTRODUCTION: Androgens may play a role in the development of ovarian cancers. Two trinucleotide repeat polymorphisms have been described in exon 1 of the androgen receptor (AR) gene that may affect its function. Previous studies of ovarian cancer and AR repeat polymorphisms have been inconsistent. METHODS: We analyzed CAG and GGC repeat length polymorphisms in the AR gene using data from a population-based case-control study of ovarian cancer that included 594 cases and 681 controls. Repeat lengths were determined by fluorescent DNA fragment analysis using ABI GeneScan software. Change point models were used to determine appropriate repeat length cutoff points by race (African American versus Caucasian) for both the shorter and longer CAG and GGC repeats. RESULTS: No relationship was observed between CAG repeat length and ovarian cancer among Caucasians. Among African Americans, having a short repeat length on either allele was associated with a 2-fold increase in ovarian cancer risk (age-adjusted odds ratio, 2.2; 95% confidence interval, 1.1-4.1). Having short CAG repeat lengths for both alleles was associated with a 5-fold increased risk for developing ovarian cancer (age-adjusted odds ratio, 5.4; 95% confidence interval, 1.4-1.7). No relationship with the GGC repeat length polymorphisms was observed. CONCLUSION: These results suggest that having a short CAG repeat length in AR increases ovarian cancer risk in African Americans. The failure to observe this relationship in Caucasians may be due to the rarity of such short CAG alleles in this population or could reflect racial differences in disease etiology. 相似文献
993.
Cutis marmorata telangiectatica congenita (CMTC) is characterized by the appearance of telangiectasia, phlebectasia, and a persistent reticular pattern of subcutaneous vasculature at or soon after birth. Up to 90% of cases are associated with systemic abnormalities, which include body asymmetry, cutaneous atrophy, neurological abnormalities, and vascular anomalies (nevus flammeus, Sturge-Weber syndrome, Klippel-Trenaunay syndrome, and capillary and cavernous hemangiomas). Glaucoma is the most commonly reported ocular association of CMTC, usually presenting in infancy. We report a case of CMTC associated with the previously unreported onset of glaucoma in mid-childhood that was managed by glaucoma drainage implant surgery and review the literature on glaucoma associated with this condition. 相似文献
994.
Demasculinization by environmental endocrine-disrupting chemicals (EDCs) is observed in many animal species but less evident in humans. Rodent studies with gestational exposure to either the fungicide vinclozolin or the insecticide methoxychlor demonstrate impaired male fertility with abnormal DNA methylation patterns in spermatozoa. Once established, these epigenetic changes may be permanent and thus paternally passed to subsequent generations. Conclusive evidence of a similar phenomenon in humans has not been established, but several observations bring up the possibility. Some, but not all, studies show an increase in male genital abnormalities after prenatal EDC exposure. Other studies demonstrate sperm abnormalities in males with EDC contact, although it is unclear as to whether this is due to prenatal or postnatal exposure. Although not examined in males with EDC exposure, one study shows gamete DNA methylation abnormalities in males with severe oligospermia. A subsequent study failed to corroborate these findings. The use of assisted reproductive techniques including intracytoplasmic sperm injection has removed natural selection barriers thus enabling reproduction in males that would otherwise be sterile. This review explores the hypothesis that prenatal EDC exposure results in transgenerational male reproductive abnormalities propagated by the use of assisted reproductive technologies. 相似文献
995.
BACKGROUND: To adopt an evidence-based approach, professionals must be able to access, identify, interpret, and critically appraise best evidence. Critical appraisal requires essential skills, such as computer literacy and an understanding of research principles. These skills also are required for professionals to contribute to evidence. METHODS: In 1996, members of the Australian Infection Control Association were surveyed to establish a profile including the extent to which they were reading infection control publications, using specific documents for policy and guideline development, developing and undertaking research, publishing research, and using computers. The relationships between demographics, computer use, and research activity were examined. RESULTS: The response rate was 63. 4% (630/993). The study group comprised mostly women (96.1%), and most (66.4%) were older than 40 years of age. Median infection control experience was 4 years (mean, 5.4 years; range, <12 months to 35 years). When developing guidelines and policies (92.7%; 584/630), infection control professionals reviewed State Health Department Infection Control Guidelines and Regulations. Research relating to infection control was undertaken by 21.5% (135/628) of the sample, and 27.6% (37/134) of this group published their research findings. Of the respondents (51.1%; 318/622) who used a computer to undertake infection control tasks, the majority (89.0%) used a personal computer for word processing. CONCLUSION: Regardless of infection control experience, Australian infection control professionals must be adequately prepared to contribute to, access, appraise, and where appropriate, apply best evidence to their practice. We suggest that computer literacy, an understanding of research principles, and familiarity with infection control literature are three essential skills that infection control professionals must possess and regularly exercise. 相似文献
996.
Hrncic R Wall J Wolfenbarger DA Murphy CL Schell M Weiss DT Solomon A 《The American journal of pathology》2000,157(4):1239-1246
Primary light-chain-associated (AL) amyloidosis is characterized by the deposition in tissue of monoclonal light chains as fibrils. With rare exception, this process is seemingly irreversible and results in progressive organ dysfunction and eventually death. To determine whether immune factors can effect amyloid removal, we developed an experimental model in which mice were injected with amyloid proteins extracted from the spleens or livers of patients with AL amyloidosis. Notably, the resultant amyloidomas were rapidly resolved, as compared to controls, when animals received injections of an anti-light-chain monoclonal antibody having specificity for an amyloid-related epitope. The reactivity of this monoclonal antibody was not dependent on the V(L) or C(L) isotype of the fibril, but rather seemed to be directed toward a beta-pleated sheet conformational epitope expressed by AL and other amyloid proteins. The amyloidolytic response was associated with a pronounced infiltration of the amyloidoma with neutrophils and putatively involved opsonization of fibrils by the antibody, leading to cellular activation and release of proteolytic factors. The demonstration that AL amyloid resolution can be induced by passive administration of an amyloid-reactive antibody has potential clinical benefit in the treatment of patients with primary amyloidosis and other acquired or inherited amyloid-associated disorders. 相似文献
997.
Murphy PE Ciarrocchi JW Piedmont RL Cheston S Peyrot M Fitchett G 《Journal of consulting and clinical psychology》2000,68(6):1102-1106
Religious belief and practices have been associated with lower levels of depression in persons dealing with stressful situations. In this study, researchers examined this relationship in 271 persons diagnosed with clinical depression. It was hypothesized that religious belief and practices would be associated with lower depression and that this relationship would be mediated by hopelessness. Religious belief, but not religious behavior, was a significant predictor of lower levels of hopelessness and depression beyond demographic variables. Through the relation of religious belief to lower levels of hopelessness, religious belief was indirectly related to less depression. There was also a small direct positive association of belief with depression, pointing to the complexity of the role belief plays for religious persons. Further study is needed for a better understanding of different ways religion affects depressed persons. 相似文献
998.
999.
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Macrovascular sensorineural hearing loss 总被引:4,自引:0,他引:4
T P Murphy 《The American journal of otology》1991,12(2):88-92
Sensorineural hearing loss (SNHL) has many etiologies including vascular sources. Vascular causes of SNHL can occur at the microvascular level. Macrovascular level may be described as arising from vessels proximal to the labyrinthine artery or those vessels that can be visualized without the aid of a microscope. Otologic symptomatology and diagnostic evaluation of the SNHL may reveal a macroscopic vascular source. Representative cases of macrovascular sensorineural hearing loss due to aneurysm, arteriovenous malformation, and vertebrobasilar artery dolichoectasia are presented. 相似文献