首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3460篇
  免费   309篇
  国内免费   32篇
耳鼻咽喉   78篇
儿科学   133篇
妇产科学   66篇
基础医学   366篇
口腔科学   50篇
临床医学   277篇
内科学   748篇
皮肤病学   251篇
神经病学   175篇
特种医学   231篇
外科学   525篇
综合类   241篇
一般理论   6篇
预防医学   186篇
眼科学   77篇
药学   147篇
中国医学   14篇
肿瘤学   230篇
  2023年   48篇
  2022年   54篇
  2021年   109篇
  2020年   82篇
  2019年   94篇
  2018年   98篇
  2017年   74篇
  2016年   94篇
  2015年   99篇
  2014年   114篇
  2013年   133篇
  2012年   176篇
  2011年   213篇
  2010年   97篇
  2009年   107篇
  2008年   141篇
  2007年   171篇
  2006年   187篇
  2005年   151篇
  2004年   136篇
  2003年   138篇
  2002年   129篇
  2001年   100篇
  2000年   113篇
  1999年   103篇
  1998年   57篇
  1997年   59篇
  1996年   45篇
  1995年   41篇
  1994年   60篇
  1993年   48篇
  1992年   59篇
  1991年   48篇
  1990年   42篇
  1989年   50篇
  1988年   45篇
  1987年   55篇
  1986年   47篇
  1985年   37篇
  1984年   25篇
  1983年   14篇
  1982年   11篇
  1981年   9篇
  1980年   7篇
  1979年   16篇
  1978年   11篇
  1977年   8篇
  1974年   7篇
  1973年   8篇
  1967年   6篇
排序方式: 共有3801条查询结果,搜索用时 0 毫秒
81.
82.
OBJECTIVE: To compare biomechanical strength of deep-frozen versus lyophilized large cortical allografts. DESIGN: In vivo transplantation studies performed in tibia of adult cats using 4 cm deep-frozen and lyophilized, gamma-irradiated allografts to bridge large cortical defect model. BACKGROUND: Bridging large cortical bone defect is a challenging problem. Options include autografts, allografts, bioceramics and prostheses. Allografts provide a suitable option. METHODS: Forty mature cats were used. A large defect (4 cm) was created in mid-diaphysis of right tibia. In 16 cats, cortical defect was reconstructed using deep-frozen allografts (-80 degrees C) with intra-medullary rodding. In another 16 cats, lyophilized, gamma-irradiated allografts were used. Observation periods include 8, 12, 16 and 24 weeks. The specimens were procured together with unoperated legs as controls. Mechanical testing was performed using a materials testing machine with torsion test device of up to 500 Nm at speed of 0.18 rpm. Parameters studied included maximum torque, torsional stiffness and energy of absorption. RESULTS: Deep-frozen allografts did not reach 100% strength, achieving only 64% at 6 months. In marked contrast, lyophilized allografts were significantly weaker with only 12% maximum torque strength at 6 months. Lyophilized allografts were significantly weaker than deep-frozen allografts in all observation periods (p < 0.05). CONCLUSION: Deep-frozen allografts did not reach 100% normal strength and were significantly weaker than non-vascularised autografts. Lyophilized allografts were significantly weaker than deep-frozen allografts. RELEVANCE: For the reconstruction of massive cortical bone defects, only deep-frozen cortical allografts should be used. Lyophilized allografts are not suitable.  相似文献   
83.
84.
Patients with idiopathic hypereosinophilic syndrome (HES) show persistent hypereosinophilia of unknown etiology that is associated with end-organ damage. Different treatments, including the use of corticosteroids and cytotoxics, have been investigated for HES with modest success. We describe a patient with HES who had significant end-organ damage from hypereosinophilia and remained refractory to conventional therapy. Therapy with imatinib mesylate, a selective tyrosine kinase inhibitor that is highly effective in treating patients with BCR-ABL-positive chronic myeloid leukemia, was tried with the patient. The result was impressive, with hematologic remission achieved after 12 days of administration. Our finding concurs with recent reports that imatinib mesylate may be a promising agent in the treatment of some cases of HES.  相似文献   
85.
86.
Journal of Thrombosis and Thrombolysis - Acute ischemic stroke (AIS) is a life-threatening complication of coronavirus disease 2019 (COVID-19) infection. Increasing reports suggest an association...  相似文献   
87.
Hashimoto’s encephalopathy (HE), which carries kaleidoscopic clinical presentations, is easily misdiagnosed in clinical practice. Early diagnosis and prompt initiation of steroid therapy are associated with good prognosis. We describe a 50-year-old female patient who had subclinical hypothyroidism and who presented herself with gradual cognitive impairment, accompanied with auditory hallucination and delusion. Increased anti-thyroid antibodies titers were found in her serum and cerebrospinal fluid. The HE diagnosis was confirmed using the laboratory test for anti-thyroid antibodies along with the patient’s clinical presentation. We treated her with steroid pulse therapy, and the results were favorable. We highlight this case to call for early diagnosis and prompt intervention of HE in clinical practice.  相似文献   
88.
While qualitative methods have gained considerable recognition in medical education research, employing multiple qualitative data sources in assessing long‐term educational impact is rare. Utilising in‐depth data analysis method to six cross‐sectional cohorts (2004–2009) of students’ reflection papers (= 213), this article demonstrates how students experienced subtle but important shifts in their attitudes (including personal, professional and spiritual domains) after making field visits to a hospice centre as part of the Special Needs Dentistry module. For retrospective assessment of learning retention, a pilot focus group was conducted with three junior faculty members who participated in the field visits to a hospice during their own undergraduate training. A subsequent focus group was conducted with graduates of the 2008 (n = 8) cohort using a refined discussion guide arising from the analysis of pilot group results. Graduates were unanimous in stating that the visits had sown ‘seeds’ in their minds and hearts, seeds which started to grow after they completed dental school and began to practice. This is demonstrative of the long‐term positive educational impact of the pedagogical design that entailed a special site visit coupled with post‐visit debrief and written reflection.  相似文献   
89.
90.
BackgroundLong-acting injectable (LAI) antipsychotics improve medication adherence in patients with schizophrenia and extend the duration of therapeutic drug levels but with administration of an increased dose. Real-world mortality data in patients prescribed LAIs are lacking. We conducted a population-based cohort study to estimate and compare the incidence rates of all-cause death and completed suicide in patients with schizophrenia/schizoaffective disorder exposed to LAIs and oral antipsychotics.MethodsPatients with a diagnosis of schizophrenia/schizoaffective disorder between January 1, 2015 and November 30, 2019 were enrolled from the Taiwan National Health Insurance Research Database and linked to Death Registry records. Eligible patients were new antipsychotic users. Relative risks of death for each antipsychotic compared with oral paliperidone were evaluated using a Cox proportional hazard model adjusted for age, sex, Charlson Comorbidity Index, index year, bipolar or major depressive or other mood disorders, mental disorders due to drug use, and baseline hospitalization frequency.ResultsThere were 228,791.08 person-years of follow-up (mean 2.48 years). The incidence rates of all-cause death in users of LAI paliperidone administered monthly (PP1M) and every 3 months (PP3M) were 7.40/1,000 person-years (95% confidence interval 5.94–9.11) and 9.93 (5.88–15.79), respectively. The incidences of completed suicide were 2.03/1,000 person-years (1.32–2.99) and 3.10 (1.14–6.88), respectively. No significant associations were observed between PP1M and PP3M compared to oral paliperidone in incidences of all-cause death or for completed suicide.DiscussionNo increased risk of all-cause death or completed suicide was observed in users of antipsychotic LAIs, including PP1M and PP3M.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号