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31.
32.
Striatal dopamine transporter binding in neuroleptic-naive patients with schizophrenia studied with positron emission tomography 总被引:3,自引:0,他引:3
Laakso A Vilkman H Alakare B Haaparanta M Bergman J Solin O Peurasaari J Räkköläinen V Syvälahti E Hietala J 《The American journal of psychiatry》2000,157(2):269-271
OBJECTIVE: Recent in vivo imaging studies indicate a dysregulated presynaptic function of the striatal dopaminergic system in patients with schizophrenia. To further explore the basis of this phenomenon, the authors studied brain dopamine transporter binding in vivo in patients with first-episode, never-medicated schizophrenia. METHOD: Nine patients with schizophrenia and nine healthy matched comparison subjects were recruited. Striatal dopamine transporter binding was measured with positron emission tomography and a specific dopamine transporter ligand, [(18)F]CFT, a radiolabeled form of 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane. RESULTS: Average caudate and putamen dopamine transporter binding potentials were almost identical in the patients and comparison subjects, but the patients lacked the right-left asymmetry of the caudate dopamine transporter binding seen in the comparison group. CONCLUSIONS: Average striatal dopamine transporter density is unaltered in neuroleptic-naive patients with schizophrenia. However, patients lack asymmetry in caudate dopamine transporter binding, which conforms with disrupted brain lateralization in this disorder. 相似文献
33.
Hippocampal volume measurements using magnetic resonance imaging (MRI) and assessment of performance in tests of delayed recall are among the most useful aids for diagnosing early Alzheimer's disease (AD) on an individual level. However, their comparative diagnostic accuracy has not been previously addressed. In this study we compared the diagnostic accuracy of these two methods in 57 patients with probable AD according to the NINCDS-ADRDA criteria, and 34 age- and gender-matched control subjects. The discriminatory power of the hippocampal volumes and delayed recall performance, Russel's Adaptation of the Visual Reproduction Test (VRT), were compared in discrimination function and receiver operator characteristic analyses. Right and left hippocampal volumes resulted in correct classification of 85.7-86.8% of the study subjects, respectively, while performance in the VRT resulted in correct classification of 93.4% of subjects. The area under curve value was 0.93 for the left hippocampus and 0.96 for the VRT. These data suggest that assessment of delayed recall with the VRT is of high diagnostic accuracy, and may surpass the diagnostic accuracy of hippocampal volumetry. 相似文献
34.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation. 相似文献
35.
Iron-overload diseases frequently develop hepatocellular carcinoma. The
genotoxic mechanism whereby iron is involved in hepatocarcinogenesis might
involve an oxidative process via the intermediate production of reactive
oxygen species. This was presently investigated by examining kinetics of
formation and repair of DNA base lesions in primary rat hepatocyte cultures
supplemented with the iron chelate, ferric nitrilotriacetate Fe-NTA (10 and
100 microM). Seven DNA base oxidation products have been identified in DNA
extracts by gas chromatography- mass spectrometry, which showed a
predominance of oxidized-purines (8- oxo-guanine, xanthine, fapy-adenine,
2-oxo-adenine) above oxidized pyrimidines (5-OHMe-uracil, 5-OH-uracil,
5-OH-cytosine) in control cultures. All these DNA oxidation products
revealed a significant dose- dependent increase at 4 to 48 h after Fe-NTA
supplementation, among which fapy-adenine showed the highest increase and
5-OH-cytosine was the least prominent. Involvement of iron in this
oxidative process was established by a correlation between extent in DNA
oxidation and intracellular level of toxic low molecular weight iron. DNA
excision- repair activity was estimated by release of DNA oxidation
products in culture medium. All the seven DNA oxidation products were
detected in the medium of control cultures and showed basal repair
activity. This DNA repair activity was increased in a time- and
dose-dependent fashion with Fe-NTA. Oxidized-pyrimidines, among which was
5-OHMe-Uracil, were preferentially repaired, which explains the low levels
detected in oxidized DNA. Since oxidized bases substantially differed from
one another in terms of excision rates from cellular DNA, specific
excision- repair enzymes might be involved. Our findings, however,
demonstrate that even though DNA repair pathways were activated in
iron-loaded hepatocyte cultures, these processes were not stimulated enough
to prevent an accumulation of highly mutagenic DNA oxidative products in
genomic DNA. The resulting genotoxic effect of Fe-NTA might be relevant in
understanding the hepatocarcinogenic evolution of iron-overload diseases.
相似文献
36.
37.
Kubaszek A Pihlajamäki J Komarovski V Lindi V Lindström J Eriksson J Valle TT Hämäläinen H Ilanne-Parikka P Keinänen-Kiukaanniemi S Tuomilehto J Uusitupa M Laakso M;Finnish Diabetes Prevention Study 《Diabetes》2003,52(7):1872-1876
High levels of cytokines are risk factors for type 2 diabetes. Therefore, we investigated whether the promoter polymorphisms of the tumor necrosis factor-alpha (TNF-alpha; G-308A) and interleukin 6 (IL-6; C-174G) genes predict the conversion from impaired glucose tolerance (IGT) to type 2 diabetes in the Finnish Diabetes Prevention Study. Altogether, 490 overweight subjects with IGT whose DNA was available were randomly divided into one of the two treatment assignments: the control group and the intensive, individualized diet and exercise intervention group. The -308A allele of the TNF-alpha gene was associated with an approximate twofold higher risk for type 2 diabetes compared with the G-308G genotype (odds ratio 1.80, 95% CI 1.05-3.09; P = 0.034). Subjects with both the A allele of the TNF-alpha gene and the C-174C genotype of the IL-6 gene had a 2.2-fold (CI 1.02-4.85, P = 0.045) higher risk of developing type 2 diabetes than subjects without the risk genotypes. We conclude that the -308A allele of the promoter polymorphism (G-308A) of the TNF-alpha gene is a predictor for the conversion from IGT to type 2 diabetes. Furthermore, this polymorphism seems to have a gene-gene interaction with the C-174C genotype of the IL-6 gene. 相似文献
38.
This article is based on a study of children's experiences of being in care in which children were given the opportunity to choose either their own social worker or an outside researcher to interview them for the purposes of the research. We examine here how the children (N?=?15) describe their choice of interviewer and also explore how the social workers (N?=?8) experience their role as research interviewers. The findings highlight that there is no single reason for children to choose either a social worker or a researcher to be the interviewer. Familiarity, in particular, can either be a motivation or an obstacle. The dual positions of children as research interviewees and as clients as well as the dual positions of social workers both supported and hindered the interviews. Social workers reported new insights into their knowledge about children’s views as a result of the research interview experience. It is argued that the choice of the interviewer may be an option for some children to have their voice heard in research. Ethical balancing and critical dialogue are also suggested as having a role. 相似文献
39.
Yuli R Tak Rinka MP Van Zundert Rowella CWM Kuijpers Boukje S Van Vlokhoven Hettie FW Rensink Rutger CME Engels 《BMC public health》2012,12(1):21
Background
The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well. 相似文献40.
Clonal Analysis of Regulatory T Cell Defect in Patients with Autoimmune Polyendocrine Syndrome Type 1 Suggests Intrathymic Impairment 下载免费PDF全文
T.‐T. Koivula S. M. Laakso H. J. Niemi E. Keklinen P. Laine L. Paulin P. Auvinen T. P. Arstila 《Scandinavian journal of immunology》2017,86(4):221-228
Mutations in the autoimmune regulator gene disrupt thymic T cell development and negative selection, leading to the recessively inherited polyendocrine autoimmune disease autoimmune polyendocrine syndrome type 1 (APS‐1). The patients also have a functional defect in the FOXP3+ regulatory T cell population, but its origin is unclear. Here, we have used T cell receptor sequencing to analyse the clonal relationship of major CD4+ T cell subsets in three patients and three healthy controls. The naive regulatory T cells showed little overlap with helper T cell subsets, supporting divergence in the thymus. The activated/memory regulatory T cell subset displayed more sharing with helper T cells, but was mainly recruited from the naive regulatory T cell population. These clonal patterns were very similar in both patients and controls. However, naive regulatory T cells isolated from the patients had a significantly longer T cell receptor complementarity‐determining region 3 than any other population, suggesting failure of thymic selection. These data indicate that the peripheral differentiation of regulatory T cells in APS‐1 patients is not different from that in healthy controls. Rather, the patients' naive regulatory T cells may have an intrinsic defect imprinted already in the thymus. 相似文献