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41.
A 70.9% majority of the U.S. male veterans in a nationwide sample appraised the impact of their service in Vietnam on their present lives as mainly positive. A substantial minority, 41.7%, judged the effects to be highly salient. With controls on level of exposure to war-zone stressors measured with data from military records, the valence and salience of these appraisals are investigated in relation to posttraumatic stress disorder (PTSD) and other indicators of wartime and postwar functioning. The results are consistent with the hypothesis that mainly positive tertiary appraisals are affirmations of successful wartime and postwar adaptation rather than defensive denials related to maladaptive outcomes. The possibility that mainly positive tertiary appraisals also contribute to successful postwar adaptation is discussed.  相似文献   
42.

Background

Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil.

Methods

This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units.

Results

Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection.

Conclusions

Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.  相似文献   
43.
Protein S is a vitamin K-dependent plasma protein that functions as an APC-cofactor, but also exhibits anticoagulant activity in the absence of APC. The Heerlen polymorphism of protein S is characterized by a Ser460Pro substitution and lacks glycosylation at Asn458. It is associated with decreased protein S levels due to selective deficiency of free protein S Heerlen. To understand the lack of thrombotic complications associated with the protein S Heerlen mutation, we compared recombinant protein S Heerlen, wild type (wt) protein S and plasma-derived protein S. wt-Protein S and protein S Heerlen each bound 1:1 to C4BP with dissociation constants of 0.27 and 0.33 nM, respectively. Both wt-protein S and protein S Heerlen, either free or in complex with C4BP, were equally active as prothrombinase inhibitors in the absence of APC. All three protein S preparations stimulated APC-catalyzed inactivation of normal FVa, FVa Leiden and FVIIIa to the same extent. If extrapolated to plasma, it is not likely that the decreased free protein S levels in carriers of the protein S Heerlen mutation are compensated by an increased anticoagulant activity of protein S Heerlen-C4BP complexes. It is possible that an unrecognized plasma factor selectively enhances the anticoagulant activity of protein S Heerlen. If not, the reduction of free protein S levels in heterozygous protein S Heerlen-carriers combined with (low) normal total protein S levels apparently minimally affects the total anticoagulant activity of protein S (APC-cofactor and APC-independent activity) and hence is not associated with increased risk of venous thrombosis.  相似文献   
44.
The concept of fetal programming is an area that is now under rigorous investigation in many laboratories throughout the world. We need to engender a fascination in all segments of society, not just pregnant women, about life in the womb.

Conclusion: Everyone needs to understand that improving the condition of the fetus will have personal, social and economic benefits. The time has come to realize that, in a sense, it is not just women who are pregnant but it is the family and the whole of society.  相似文献   
45.
Fifty-eight women with posttraumatic stress disorder (PTSD) related to childhood abuse were randomly assigned to a 2-phase cognitive-behavioral treatment or a minimal attention wait list. Phase 1 of treatment included 8 weekly sessions of skills training in affect and interpersonal regulation; Phase 2 included 8 sessions of modified prolonged exposure. Compared with those on wait list, participants in active treatment showed significant improvement in affect regulation problems, interpersonal skills deficits, and PTSD symptoms. Gains were maintained at 3- and 9-month follow-up. Phase 1 therapeutic alliance and negative mood regulation skills predicted Phase 2 exposure success in reducing PTSD, suggesting the value of establishing a strong therapeutic relationship and emotion regulation skills before exposure work among chronic PTSD populations.  相似文献   
46.
The behavioral model of service use was employed to identify predictors of mental health treatment seeking and treatment readiness among individual with PTSD (N = 2,713) in data from the 1996 National Anxiety Disorders Screening Day (NADSD). This model examines the contribution of predisposing (age, sex, marital status, race/ethnicity, education), enabling (employment, geographic location), perceived need (interference of symptoms with daily life), and evaluated need (other diagnoses) factors to treatment seeking and treatment readiness for individuals with PTSD. Results indicate that although need factors (interference by anxiety symptoms with daily life, diagnosis of panic disorder) are related to both receiving and readiness for treatment, predisposing (age, marital status, minority race) factors influence which individuals receive treatment for PTSD.  相似文献   
47.
The well-documented association between combat-related PTSD (C-PTSD) and other mental disorders may be an artifact of shared familial vulnerability. This study uses a co-twin control design to examine whether the association between C-PTSD and other mental disorders persists after adjusting for shared familial vulnerability. Data were from male monozygotic twin pairs in the Vietnam Era Twin Registry. Logistic regression analyses demonstrated that combat exposure, adjusted for C-PTSD, was significantly associated with increased risk for alcohol and cannabis dependence and that C-PTSD mediated the association between combat exposure and both major depression and tobacco dependence. We conclude C-PTSD comorbidity persists after controlling for shared vulnerability. Combat exposure is directly and indirectly, through C-PTSD, associated with increased risk for other mental disorders.  相似文献   
48.
Immunosuppressive therapy is best achieved with a combination of agents targeting multiple activation steps of T cells. In transplantation, cyclosporine A (CsA) or tacrolimus (FK506) are successfully combined with rapamycin (Rap). Rap and CsA were first considered for combination therapy because FK506 and Rap target the same intracellular protein and thus may act in an antagonistic way. However, in clinical studies, FK506+Rap proved to be effective. To date, there is no in vitro data supporting these in vivo findings, and it is unclear whether the observed effects are T-cell mediated. In a human polyclonal allogeneic in vitro model, we found that although combined drug treatment markedly reduced expansion of naive T cells, T-cell activation occurred irrespective of the drug combination used. The induction of cytotoxic effector T cells was reduced by CsA+Rap but completely abolished by FK506+Rap. Importantly, combined immunosuppression allowed generation of memory CD4+ and CD8+ T cells and hence did not result in T-cell anergy. However, FK506+Rap treatment resulted in a reduced number of allospecific memory T cells showing a decreased cell-cycle turnover and cytokine producing capacity. In contrast, CsA+Rap treatment led to increased memory T-cell numbers responding with elevated kinetics. The ability of Rap to promote apoptosis, which contributes to T-cell suppression, remained unaffected upon combination with FK506 or CsA. These data support the combined use of FK506+Rap over CsA+Rap for immunosuppressive therapy.  相似文献   
49.
50.
An experimental infection with classical swine fever (CSF) virus in E2 sub-unit marker vaccine vaccinated gilts was conducted in order to evaluate the effect of vaccination on virus transmission and course of the disease. Therefore, clinical signs as well as horizontal and vertical virus transmission were monitored in two inoculated, non-vaccinated and 10 vaccinated conventional gilts, housed in individual sow boxes. Within 10 days post-inoculation, all vaccinated gilts became infected. Depending on the definition of the infectious period, two different estimates of R0 were calculated (R0=14.8 and 3.3), both significantly larger than 1 (P<0.01). In three out of the eight vaccinated pregnant gilts vertical virus transmission occurred, resulting in infected offspring. Based on the results of this experiment, it can be concluded that double vaccination with an E2 sub-unit marker vaccine only protects pregnant gilts from the clinical course of the disease but does not prevent horizontal nor vertical spread of the CSF virus.  相似文献   
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