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91.
Goedert KM, Chen P, Botticello A, Masmela JR, Adler U, Barrett AM. Psychometric evaluation of neglect assessment reveals motor-exploratory predictor of functional disability in acute-stage spatial neglect.ObjectiveTo determine the psychometric properties of 2 neglect measures, the Behavioral Inattention Test (BIT)-conventional and the Catherine Bergego Scale (CBS), in acute spatial neglect. Spatial neglect is a failure or slowness to respond, orient, or initiate action toward contralesional stimuli, associated with functional disability that impedes stroke recovery. Early identification of specific neglect deficits may identify patients likely to experience chronic disability. However, psychometric evaluation of assessments has focused on subacute/chronic populations.DesignCorrelational/psychometric study.SettingInpatient rehabilitation hospital.ParticipantsScreening identified 51 consecutive patients with a right-hemisphere stroke with left neglect (BIT score <129 or CBS score >11) tested an average of 22.3 days poststroke.InterventionsNot applicable.Main Outcome MeasuresWe obtained BIT, CBS, and Barthel Index assessments for each participant and clinical and laboratory measures of perceptual-attentional and motor-intentional deficits.ResultsThe BIT showed good reliability and loaded onto a single factor. Consistent with our theoretical prediction, principal components analysis of the CBS identified 2 underlying factors: Where perceptual-attentional items (CBS-PA) and embodied, motor-exploratory items (CBS-ME). The CBS-ME uniquely predicted deficits in activities of daily living (ADLs) assessed by using the Barthel Index, but did not predict clinical and laboratory assessments of motor-intentional bias. More severe neglect on the CBS-PA correlated with greater Where perceptual-attentional bias on clinical and laboratory tests, but did not uniquely predict deficits in ADLs.ConclusionsOur results indicate that assessments of spatial neglect may be used to detect specific motor-exploratory deficits in spatial neglect. Obtaining CBS-ME scores routinely might improve the detection of acute-stage patients with spatial action deficits requiring increased assistance that may persist to the chronic stage.  相似文献   
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Little is known about cellular immunity to human herpesvirus 8 (HHV-8), the virus associated with Kaposi's sarcoma (KS). T cell proliferative responses to purified HHV-8 were measured in homosexual men, a group with elevated HHV-8 seroprevalence and high risk of KS. None of 20 blood donor controls had T cell responses to HHV-8. Among human immunodeficiency virus (HIV)-negative homosexual men, 8 (42%) of 19 HHV-8 seropositive men responded as did 4 (16%) of 25 HHV-8 seronegative men. Among HIV-positive homosexual men, however, none of 21 HHV-8 seropositives had T cell responses to HHV-8, even though most responded to common recall antigens, and 10 had >/=400 CD4 cells/mm3. The results suggest that HHV-8 T cell proliferative responses are common in HIV-negative homosexual men and that HIV infection may be associated with diminished HHV-8 cellular immunity, possibly before there is substantial depletion of CD4 cells. If correct, this could explain why KS occurs relatively early in HIV infection/AIDS.  相似文献   
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Coding region and intronic mutations in the tau gene cause frontotemporal dementia and parkinsonism linked to chromosome 17. Intronic mutations and some missense mutations increase splicing in of exon 10, leading to an increased ratio of four-repeat to three-repeat tau isoforms. Secondary structure predictions have led to the proposal that intronic mutations and one missense mutation destabilize a putative RNA stem-loop structure located close to the splice-donor site of the intron after exon 10. We have determined the three-dimensional structure of this tau exon 10 splicing regulatory element RNA by NMR spectroscopy. We show that it forms a stable, folded stem-loop structure whose thermodynamic stability is reduced by frontotemporal dementia and parkinsonism linked to chromosome 17 mutations and increased by compensatory mutations. By exon trapping, the reduction in thermodynamic stability is correlated with increased splicing in of exon 10.  相似文献   
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To determine the incidence and prognostic significance of thrombocytopenia among hemophiliacs, we analyzed clinical and hematologic data from the Multicenter Hemophilia Cohort study. Nineteen percent of HIV-infected subjects had thrombocytopenia (platelet count of <100,000/mm3) noted at least once, compared to 3% of HIV-uninfected subjects. For HIV-infected subjects, the prevalence of thrombocytopenia rose in the first 5 years after seroconversion and was twice as common in subjects age >35 years compared to younger subjects. The risk increased after an AIDS-defining illness, particularly among older subjects, nearly one-half of whom had thrombocytopenia within 1 year after AIDS. When adjusted for age and CD4-positive lymphocyte counts, thrombocytopenia was associated with an increased risk of death [relative risk (RR) 1.7, 95%Cl = 1.2–2.3] but with little change in the risk of progression to AIDS (RR = 1.2, 95%Cl = 0.8–1.7). Treatment with zidovudine was associated with a decreased risk of thrombocytopenia (RR = 0.5, 95%Cl = 0.3–0.7). Although 59 HIV-infected subjects died of hemorrhage, only 11 (19%) of the 59 had a reported platelet count of <50,000/mm3, and only 2 (3%) of the deaths were temporally associated with thrombocytopenia. Thus, the risk of death was increased for thrombocytopenia HIV-infected hemophiliacs but this was not explained by an increased risk of developing AIDS and was rarely associated with death from bleeding. Am. J. Hematol. 54:296–300, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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Background:

Immune perturbation likely affects the development of Kaposi sarcoma (KS) among people infected with the KS-associated herpesvirus (KSHV). We tested whether KSHV-seropositive individuals or cases of classic KS (cKS), which typically originates in the leg, had differing delayed-type hypersensitivity (DTH) in the forearm or leg.

Methods:

Mantoux DTH with three antigens (Candida, tetanus, PPD) was performed on the forearm and leg of 15 cKS cases, 14 KSHV-positives without KS, and 15 KSHV-negative controls. The diameters of induration responses were compared by group and body site.

Results:

Leg DTH was greater than forearm DTH among controls (mean difference 5.6 mm, P=0.0004), whereas this was not observed in cKS cases (−2.2 mm, P=0.32) or KSHV-positives (0.5 mm, P=0.56). Leg-minus-forearm DTH difference was greater in controls compared with cKS cases (P=0.004) and KSHV-positives (P=0.002). Leg-plus-forearm DTH was similar in controls (mean 28.2 mm) and cKS cases (24.5 mm, P=0.60), but it was reduced in KSHV-positives (11.8 mm, P=0.02), particularly in the leg (P=0.004) and marginally in the forearm (P=0.07).

Conclusion:

KS cases had weaker DTH only in the leg, whereas both body sites appeared weaker in KSHV-positives without KS. Both systemic and regional immune alterations may influence the development of this malignancy.  相似文献   
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