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101.
Lemos PA de Feyter PJ Serruys PW Saia F Arampatzis CA Disco C Mercado N Mainar V Morís C van den Bos AA Berghoefer G 《International journal of cardiology》2005,98(3):479-486
BACKGROUND: To evaluate the impact of the extent of coronary disease (single- or multivessel) and of fluvastatin treatment on the incidence of long-term cardiac atherosclerotic complications in the Lescol Intervention Prevention Study (LIPS). METHODS: A total of 1063 patients with single-vessel disease and 614 patients with multivessel disease were randomized to receive fluvastatin (40 mg bid) or placebo for at least 3 years following a first successful percutaneous coronary intervention. The incidence of cardiac atherosclerotic events (cardiac death, non-fatal myocardial infarction, and coronary re-interventions not related to restenosis) was evaluated. RESULTS: Patients with multivessel disease tended to be older and presented a higher prevalence of associated risk factors and cardiovascular antecedents. The presence of multivessel disease markedly increased the risk of cardiac atherosclerotic events compared with single-vessel disease among patients allocated to placebo (RR 1.67 [95% CI: 1.24-2.25]; p<0.001). In patients treated with fluvastatin, however, no significant differences in long-term outcomes were observed between patients with multivessel disease and patients single-vessel disease (RR 1.28 [95% CI: 0.90-1.81]; p=0.2). CONCLUSIONS: Multivessel coronary disease impaired the 4-year outcomes after percutaneous intervention. However, the hazardous effect of multivessel disease was significantly reduced by long-term fluvastatin treatment. 相似文献
102.
The neural basis of feedback expectation, which is crucial in learning theory, has only been minimally studied. Stimulus‐preceding negativity (SPN), an ERP component that appears prior to the presentation of feedback, has been proposed as being related to feedback expectation. The present study showed, for the first time, amplitude modulations of the SPN component during learning acquisition in a trial‐by‐trial associative learning task. The results indicate that SPN could be a plausible electrophysiological index of the cognitive processes engaged while expecting the appearance of relevant feedback during reinforcement learning. 相似文献
103.
D. Bacigalupe W. Basso S. G. Caspe G. Moré L. Lischinsky M. L. Gos M. Leunda L. Campero D. P. Moore G. Schares C. M. Campero M. C. Venturini 《Parasitology research》2013,112(7):2585-2592
Neospora caninum infection is a major cause of abortion in cattle. The objectives of this study were to genetically characterize the N. caninum NC-6 Argentina isolate using a multilocus microsatellite analysis approach and to study its biological behavior by experimental inoculations into seronegative and seropositive pregnant cattle, evaluating the humoral and cellular immune response elicited and the occurrence of transplacental transmission and fetopathy. Pregnant cows (65 days of gestation) seropositive and seronegative to N. caninum were intravenously inoculated with tachyzoites of the NC-6 Argentina N. caninum strain and slaughtered at 108?±?2 days of gestation. Serum samples were analyzed for N. caninum antibodies by indirect fluorescent antibody test. The cellular immune response was analyzed by detection of gamma interferon (γIFN) production in blood cells. Tissue samples from dams, fetuses, and placental cotyledons were processed by histopathological and immunohistochemical techniques and examined for N. caninum DNA by PCR. Positive DNA samples were further analyzed by multilocus microsatellite typing for N. caninum. Inoculated animals had significantly higher N. caninum antibody titers and γIFN production than control animals. One seropositive inoculated cow aborted, one seronegative cow had a non-viable fetus, and the remaining fetuses from the experimentally inoculated dams had histopathologic lesions. The PCR was positive in 3/4 fetuses from seronegative inoculated cows and in 2/3 fetuses from seropositive inoculated cows. Multilocus microsatellite analysis revealed that the N. caninum DNA present in fetuses and placentas had an identical pattern to NC-6 Argentina strain. The NC-6 Argentina strain proved to be able to cross the placenta and to induce fetopathy in both the seropositive and seronegative dams. 相似文献
104.
The ctpA gene encodes the C-terminal processing protease for the D1 protein of the photosystem II reaction center complex. 总被引:8,自引:0,他引:8 下载免费PDF全文
P R Anbudurai T S Mor I Ohad S V Shestakov H B Pakrasi 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(17):8082-8086
The D1 protein of the photosystem II (PSII) complex in the thylakoid membrane of oxygenic photosynthetic organisms is synthesized as a precursor polypeptide (pD1) with a C-terminal extension. Posttranslational processing of the pD1 protein is essential to establish water oxidation activity of the PSII complex. We have recently identified a gene, ctpA, a mutation in which resulted in a loss of PSII activity in the cyanobacterium Synechocystis sp. PCC 6803. To study the function of the CtpA protein, we inactivated the ctpA gene by inserting a kanamycin-resistance gene into its coding sequence. The resultant mutant strain, T564, had no PSII-mediated water oxidation activity, but it had normal cytochrome b6f and photosystem I activities. Measurements of thermoluminescence profiles and rates of reduction of 2,6-dichlorophenolindophenol indicated that PSII complexes in the mutant cells had functional reaction centers that were unable to accept electrons from water. Immunoblot analysis showed that D1, D2, CP47, CP43, and the alpha subunit of cytochrome b559, five integral membrane proteins of PSII, were present in T564 cells. Interestingly, the D1 protein in the mutant cells was 2 kDa larger than that in wild-type cells, due to the presence of a C-terminal extension. We conclude that the CtpA protein is a processing enzyme that cleaves off the C-terminal extension of the D1 protein. Interestingly, the CtpA protein shows significant sequence similarity to the interphotoreceptor retinoid-binding proteins in the bovine, human, and insect eye systems. 相似文献
105.
106.
Lee Yaari Yona Kosashvili Ganit Segal Shai Shemesh Steven Velkes Amit Mor Ronen Debi Benjamin Bernfeld Avi Elbaz 《Clinics in Orthopedic Surgery》2015,7(2):191-198
Background
Many factors contribute to suboptimal results after total knee arthroplasty (TKA) but little is known regarding the value of postsurgical rehabilitation after TKA. We examined the effects of an enhanced closed kinematic chain exercises program (AposTherapy) on gait patterns and clinical outcomes among patients with a lack of progress in their postsurgical rehabilitation.Methods
Twenty-two patients were prospectively followed during the study. Gait spatiotemporal parameters were measured at the initial evaluation, after 15 minutes of therapy, and after 3 months of therapy. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the short form (SF) 36 health survey were completed by patients before treatment and after 3 months of treatment.Results
The WOMAC and SF-36 scores improved significantly after 3 months of treatment. Gait velocity, single limb support, and step length of the operated leg improved significantly even after a single 15 minutes treatment. Normal gait velocity was observed in 36% of patients after 3 months of treatment.Conclusions
A physiotherapy program that included enhanced closed kinematic chain biomechanical therapy was beneficial for patients who experienced a suboptimal rehabilitation course after TKA. 相似文献107.
108.
Experience with lamivudine therapy for hepatitis B virus infection before and after liver transplantation,and review of the literature 总被引:16,自引:0,他引:16
OBJECTIVES: To analyse the results of lamivudine therapy on suppression of hepatitis B virus (HBV) replication before transplantation and on preventing graft reinfection postoperatively. DESIGN: Long-term clinical study. SETTING: Liver Institute and Department of Transplantation of a tertiary-care university-affiliated centre. SUBJECTS: (1) 14 candidates for liver transplantation with decompensated liver disease caused by active replication of HBV; (2) six patients with recurrent HBV infection after transplantation. INTERVENTION: Lamivudine 100 mg daily; administered in group 1 before surgery and continued after in nine patients who underwent transplantation; administered in group two postoperatively only. anti-hepatitis B surface antigen immunoglobulin (HBIg) was administered postoperatively in both groups. MAIN OUTCOME MEASURES: Immunoassay evaluation of serum hepatitis B surface antigen, serum hepatitis Be antigen and serum HBV DNA (hybridization and PCR); sequencing through the tyrosine-methionine-aspartate-aspartate locus of the HBV polymerase gene in patients with lamivudine breakthrough; inflammation and fibrosis scoring on liver biopsy before and at least 2 years after lamivudine therapy in group 2. RESULTS: Pretransplantation therapy (group 1) significantly suppressed HBV replication and enabled nine patients (64.2%) to undergo transplantation. Only one patient (7.1%) had lamivudine breakthrough, and one (7.1%) had recurrent HBV. Lamivudine administration begun after transplantation (mean 48.0 months, range 30-60 months) because of graft reinfection (group 2) was associated, over the long-term, with the emergence of high mutation rates (83.3%), histological disease progression (66.6%), and hepatic failure (33.3%). CONCLUSIONS: In patients with chronic HBV infection and active viral replication, lamivudine therapy is effective when started before transplantation. However, its long-term administration after transplantation for recurrent HBV leads to high resistance rates. Combination therapy with lamivudine and HBIg immunoglobulin can substantially reduce the recurrence rate. Further studies on combination antiviral therapy are needed in this patient population. 相似文献
109.
110.