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101.
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Catalfamo  JL; Raymond  SL; White  JG; Dodds  WJ 《Blood》1986,67(6):1568-1577
A unique, intrinsic, hereditary canine platelet disorder attributable to abnormal fibrinogen receptor availability is described. Thrombopathic platelets from 13 severely affected basset hounds failed to aggregate in response to all agonists tested except thrombin. Normal platelet interaction with the various stimuli was inferred on the basis of their ability to elicit unimpaired shape change in thrombopathic platelets. No quantitative differences in major platelet membrane glycoproteins, intraplatelet fibrinogen, adenine nucleotides, or serotonin uptake were detected. Dense granule secretion was impaired. The ultrastructural appearance of thrombopathic platelets was normal. Fibrinogen-platelet interaction was evaluated by reacting platelet-rich plasma (PRP) with fibrinogen coupled to polymeric acrylonitrile beads and scoring the extent of stimulus-induced agglutination. The aggregatory responses of normal and thrombopathic platelets were closely correlated with fibrinogen receptor availability. In contrast to human platelets, epinephrine-stimulated canine platelets did not interact with immobilized fibrinogen, and arachidonate generally induced only weak agglutination. Thrombopathic platelets agglutinated fibrinogen beads at reduced rates when stimulated with physiologic doses of thrombin and high-dose calcium ionophore, A23187. Our data suggest that thrombin-mediated induction of canine platelet fibrinogen receptors may proceed by pathway(s) alternate to those shared by other platelet agonists, and/or that secreted granule constituents may act synergistically with thrombin to overcome inhibition of signal-response- coupled reactions mediating the interaction of fibrinogen with its receptor. This congenital platelet defect provides further evidence, in a species other than human, for the pivotal role of fibrinogen receptor induction in platelet aggregation.  相似文献   
103.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT.  相似文献   
104.
Post-angioplasty restenosis is a major limitation of interventional cardiology. A large body of evidence reveals that expression of myofibroblast activity promoters moves progressively from the neoadventitia to the neointima. Brachytherapy inhibits vascular cell activity (proliferation, migration), mitigates recruitment of intimal cells, and shows a favorable prophylactic effect on late vascular remodeling by preventing adventitial constriction at the injured site. These effects of brachytherapy are dose related. Clinical and experimental data demonstrate that restenosis is determined by the balance between arterial remodeling and intimal hyperplasia. Apparently, brachytherapy-induced positive remodeling plays the principal role in increasing the luminal diameter after PTCA and, in case of a lower dose or dose fall-off, to cause detrimental edge effects. With regard to clinical course, healing defects, endothelial dysfunction and stent-vessel wall malapposition are apparently important and possibly underestimated features of vascular pathology, since they may contribute to late thrombosis and delayed intimal hyperplasia in long-term course after intracoronary brachytherapy.  相似文献   
105.

Background

BEIT CURE International Hospital (BCIH) opened in 2002 providing orthopaedic surgical services to children in Malawi. This study reviews the hospital''s progress 10 years after establishment of operational services. In addition we assess the impact of the hospital''s Malawi national clubfoot programme (MNCP) and influence on orthopaedic training.

Methods

All operative paediatric procedures performed by BCIH services in the 10th operative year were included. Data on clubfoot clinic locations and number of patients treated were obtained from the MNCP. BCIH records were reviewed to identify the number of healthcare professionals who have received training at the BCIH.

Results

609 new patients were operated on in the 10th year of hospital service. Patients were treated from all regions; however 60% came from Southern regions compared with the 48% in the 5th year. Clubfoot, burn contracture and angular lower limb deformities were the three most common pathologies treated surgically. In total BCIH managed 9,842 patients surgically over a 10-year period. BCIH helped to establish and co-ordinate the MNCP since 2007. At present the program has a total of 29 clinics, which have treated 5748 patients. Furthermore, BCIH has overseen the full or partial training of 5 orthopaedic surgeons and 82 orthopaedic clinical officers in Malawi.

Conclusion

The BCIH has improved the care of paediatric patients in a country that prior to its establishment had no dedicated paediatric orthopaedic service, treating almost 10,000 patients surgically and 6,000 patients in the MNCP. This service has remained consistent over a 10-year period despite times of global austerity. Whilst the type of training placement offered at BCIH has changed in the last 10 years, the priority placed on training has remained paramount. The strategic impact of long-term training commitments are now being realised, in particular by the addition of Orthopaedic surgeons serving the nation.  相似文献   
106.
ObjectiveTo determine the efficacy of intradetrusor injections of botulinum toxin A for non-neurogenic urinary urge incontinence.MethodsWe conducted a six-month, randomized, double-blind controlled trial involving women with urinary urge incontinence. Participants received intradetrusor injections of either botulinum toxin (100U in 10 mL) via cystoscopy or a placebo control (saline injection). The primary outcome was maximum bladder capacity at cystoscopy. Secondary outcomes included quality-of-life measures, 24-hour leakage rate, patients' subjective assessment, and safety data.ResultsThere were 21 participants: 11 in the botulinum toxin (treated) group and 10 in the placebo (control) group. There were no significant differences between the groups at baseline. After six months the mean maximum bladder capacity at cystoscopy was 161.6 mL greater in the treated group than in the control group (P = 0.018). There were no differences in diary data or quality-of- life measures. The 24-hour pad test (a measure of leakage) after three months showed significant improvement in the treated group (difference 272.12 g, P = 0.016); treated subjects also showed subjective benefit at three months (difference 1.29, P = 0.007) and at six months (difference 1.16, P = 0.01). There was no significant difference in rates of urinary tract infection between groups. There was one serious adverse event (a perioperative cardiac event) in the botulinum toxin group.ConclusionBotulinum toxin increased bladder capacity at cystoscopy and reduced urinary incontinence on 24-hour pad testing in adult females with urinary urge incontinence. There was one adverse event in the group treated with botulinum toxin.  相似文献   
107.
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109.
从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。  相似文献   
110.
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