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M R Nuwer E N Miller B R Visscher E Niedermeyer J W Packwood L G Carlson P Satz W Jankel J C McArthur 《Neurology》1992,42(6):1214-1219
We conducted EEG testing in 200 asymptomatic homosexual men, half of whom were HIV seropositive. We chose to include half of the subjects because they were rated as impaired on a neuropsychological screening test. We used both traditional visual EEG interpretation and quantitative EEG analysis. Abnormal EEGs and borderline degrees of EEG slowing occurred in 32% of these men. These EEG changes were not related to HIV serostatus. EEG changes did correlate with the impaired neuropsychological test performance. Clinicians faced with abnormal EEG results or borderline EEG slowing in an asymptomatic HIV-seropositive patient should not attribute the EEG change to effects of the serostatus itself but should look for other causes. 相似文献
3.
D W Visscher R J Zarbo G Jacobsen A Kambouris G Talpos W Sakr J D Crissman 《Laboratory investigation; a journal of technical methods and pathology》1990,62(3):370-378
Using intact ethanol-fixed cytokeratin monoclonal (CAM 5.2) and propidium iodide dual-stained cells, we have performed two-color multiparametric flow cytometric (FCM) DNA analysis and S-phase fraction (SPF) determination on 165 mechanically dissociated breast carcinomas. Sixty-seven patients were axillary node positive, 33 patients node negative; 59 had biopsy only and in 8, FCM was performed on tissue from metastatic lesions. Overall, 62% of the tumors contained aneuploid cell populations. Abnormal cellular DNA content (aneuploidy) was significantly correlated with high nuclear grade (p less than 0.001), lack of estrogen receptors (p less than 0.001), presence of vascular invasion (p less than 0.04), high histologic grade (p less than 0.04), and tumor size (p less than 0.03) but not with patient age (p greater than 0.07) or axillary node status (p greater than 0.50). SPF values derived from ungated histograms had a positively skewed frequency distribution (range 2 to 30%, N = 152) with an overall median of 11% (diploid, 8.9%; aneuploid, 15.7%). Higher SPF values were significantly correlated with aneuploidy (p less than 0.001), presence of necrosis (p less than 0.001), lack of estrogen receptor (p less than 0.0001), high nuclear grade (p less than 0.001), vascular invasion (p less than 0.003), tumor size (p less than 0.006), and high histologic grade (p less than .004) but not the presence of lymph node metastases (p greater than 0.56). Mean SPF values were significantly higher when calculated from cytokeratin gated DNA histograms (14.1% versus 11.5%, p less than 0.001), probably due to exclusion of contaminating stromal/inflammatory cells; and significantly lower when calculated from debris subtracted histograms (7.8% versus 11.4%). Cytokeratin gated and debris subtracted SPF values both had a greater degree of correlation than ungated values with clinicopathologic factors of known prognostic significance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
M. M. Engelgau K. M. Narayan L. S. Geiss T. J. Thompson G. L. Beckles L. Lopez T. Hartwell W. Visscher L. Liburd 《Journal of the National Medical Association》1998,90(10):605-613
Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) is the first comprehensive community diabetes demonstration project in the United States in an African-American community. This article describes its intervention components and evaluation design. The development and implementation of Project DIRECT has included the community since the project''s beginning. Interventions are targeted in three areas: health promotion (improving diet and physical activity levels), outreach (improving diabetes awareness, detection of undiagnosed diabetes, and ensuring that persons with diabetes who are not receiving continuing diabetes care are integrated into the health-care system), and diabetes care (improving self-care, increasing access, and improving the quality of diabetes preventive care received within the health-care system). Evaluation will be internal (conducted by Project DIRECT staff to assess process outcomes in persons directly exposed to each specific intervention) and external (review of outcomes to assess the impact of the multi-intervention program at the level of the entire community). Because diabetes exacts a disproportionate toll among African Americans, the findings from this project should aid in developing strategies to lessen the burden of this disorder, particularly among minority populations. 相似文献
5.
6.
Twin studies provide estimates of genetic and environmental contributions to cognitive ability differences, but could be based
on biased samples. Here we report whole-population estimates using twins from unique mental surveys in Scotland. The Scottish
Mental Surveys of 1st June 1932 (SMS1932) and 4th June 1947 (SMS1947), respectively, administered the same validated verbal
reasoning test to almost everyone born in 1921 or 1936 and attending school in Scotland. There were 572 twin pairs from the
SMS1932, and 517 pairs from the SMS1947. Information on zygosity was unavailable. A novel application of a mixture distribution
was used to estimate genetic and environmental components of verbal reasoning variation by maximum likelihood. We found consistent
heritability (~0.70) and shared environment (~0.21) estimates. The estimates did not change substantially when additional
quantitative traits (height and weight) were added in a multivariate analysis. More generally for studies in genetics, the
methodological innovation developed here implies that large (national) data collections can provide sufficient information
on twin pairs to estimate genetic parameters, even without zygosity. 相似文献
7.
P M Visscher C S Haley H Ewald O Mors J Egeland B Thiel E Ginns W Muir D H Blackwood 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):18-24
To test the hypothesis that the same genetic loci confer susceptibility to, or protection from, disease in different populations, and that a combined analysis would improve the map resolution of a common susceptibility locus, we analyzed data from three studies that had reported linkage to bipolar disorder in a small region on chromosome 4p. Data sets comprised phenotypic information and genetic marker data on Scottish, Danish, and USA extended pedigrees. Across the three data sets, 913 individuals appeared in the pedigrees, 462 were classified, either as unaffected (323) or affected (139) with unipolar or bipolar disorder. A consensus linkage map was created from 14 microsatellite markers in a 33 cM region. Phenotypic and genetic data were analyzed using a variance component (VC) and allele sharing method. All previously reported elevated test statistics in the region were confirmed with one or both analysis methods, indicating the presence of one or more susceptibility genes to bipolar disorder in the three populations in the studied chromosome segment. When the results from both the VC and allele sharing method were considered, there was strong evidence for a susceptibility locus in the data from Scotland, some evidence in the data from Denmark and relatively less evidence in the data from the USA. The test statistics from the Scottish data set dominated the test statistics from the other studies, and no improved map resolution for a putative genetic locus underlying susceptibility in all three studies was obtained. Studies reporting linkage to the same region require careful scrutiny and preferably joint or meta analysis on the same basis in order to ensure that the results are truly comparable. 相似文献
8.
Michelle Bonnett Tracie Wallis Michelle Rossmann Nat L Pernick David Bouwman Kathryn A Carolin Daniel Visscher 《Modern pathology》2003,16(2):154-160
Appropriate follow-up of patients with needle core breast biopsies (NCBB) showing atypical hyperplasia remains unclear because previous studies show that subsequent open biopsies in variable proportions of these patients reveal ductal carcinoma in situ (DCIS) or even invasive carcinoma, indicating significant sampling artifact. NCBB with diagnoses of atypia were morphologically classified into groups as follows: I, ALH (n = 24); II, ADH with minimal cytologic atypism (n = 90); III, atypia, other (9 columnar, 2 apocrine, 11 atypical papillary); IV, severe ADH/borderline DCIS (n = 31). Mammographic and histologic features, including the number of foci of atypia in the NCBB and the calcification span, were then correlated with presence of DCIS or invasive tumor in subsequent open excisions. Open excisional biopsies showed more severe lesions in 12% of Group I-III cases (8% in Group I, 9% in Group II, and 27% in Group III), of which 15 were DCIS and one was an invasive tubular carcinoma (0.3 cm). Of the DCIS, 60% (n = 9) were < or =5 mm, and 13 of 15 (87%) were low grade. The NCBB cavity was immediately adjacent to the more severe lesions in 88% (n = 14) of cases, in keeping with sampling error. The subset showing severe ADH with borderline nuclear features in contrast was associated with a high likelihood (63%) of DCIS in follow-up excisions. NCBB with atypical papillary features also showed a high frequency of DCIS (4/11, 36%) in subsequent open excisions. Other factors associated with more severe lesions on open biopsy included the number of atypical foci in the NCBB (>4, P <.05) and the mammographic calcification span (>2.0 cm, P <.0001). Atypical lesions diagnosed in NCBB samples are radiographically and morphologically heterogeneous, accounting for the variable frequency of DCIS or invasive neoplasm identified in subsequent open excisions, which are usually focal, low grade, and a consequence of sampling artifact (i.e., adjacent to the NCBB cavity). DCIS is more likely if microcalcifications are mammographically extensive or if atypia is multifocal or is associated with borderline cytologic features. 相似文献
9.
State of creatine in mammalian heart muscle 总被引:3,自引:0,他引:3
10.
Predictors of the acquired immunodeficiency syndrome developing in a cohort of seropositive homosexual men 总被引:16,自引:0,他引:16
B F Polk R Fox R Brookmeyer S Kanchanaraksa R Kaslow B Visscher C Rinaldo J Phair 《The New England journal of medicine》1987,316(2):61-66
In a cohort of 1835 homosexual men who were seropositive for human immunodeficiency virus (HIV) on entry into a prospective study, the acquired immunodeficiency syndrome (AIDS) developed in 59 during a median follow-up of 15 months. We matched 5 seropositive controls to each case according to study center and date of enrollment and performed a case-control analysis to determine factors predictive of AIDS. In a multivariate analysis, a decreased number of T helper lymphocytes, an increased number of T suppressor lymphocytes, a low level of antibody to HIV, a high titer of cytomegalovirus antibody, and a history of sex with someone in whom AIDS developed were independently associated with subsequent AIDS. Separate analyses of risk factors for Kaposi's sarcoma and opportunistic infections failed to support previously reported associations between the use of nitrites or an elevated cytomegalovirus-antibody titer and Kaposi's sarcoma. These variables may be markers rather than determinants of disease progression. A vigorous antibody response to HIV infection may confer at least temporary protection against the progression of immunodeficiency to AIDS, or a low level of antibody to HIV may reflect a later stage of infection. The increased risk associated with a history of sex with someone in whom AIDS developed may indicate earlier infection in cases or infection with a more virulent strain of HIV. These results may be useful in counseling HIV-seropositive persons and in designing studies of clinical interventions. 相似文献