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   9503篇
  免费   613篇
  国内免费   219篇
耳鼻咽喉   205篇
儿科学   86篇
妇产科学   51篇
基础医学   1775篇
口腔科学   175篇
临床医学   933篇
内科学   2286篇
皮肤病学   365篇
神经病学   707篇
特种医学   470篇
外科学   978篇
综合类   78篇
现状与发展   1篇
预防医学   352篇
眼科学   119篇
药学   931篇
中国医学   171篇
肿瘤学   652篇
  2024年   3篇
  2023年   56篇
  2022年   234篇
  2021年   490篇
  2020年   212篇
  2019年   271篇
  2018年   322篇
  2017年   229篇
  2016年   362篇
  2015年   457篇
  2014年   568篇
  2013年   613篇
  2012年   1053篇
  2011年   934篇
  2010年   489篇
  2009年   406篇
  2008年   520篇
  2007年   534篇
  2006年   411篇
  2005年   389篇
  2004年   278篇
  2003年   271篇
  2002年   223篇
  2001年   181篇
  2000年   176篇
  1999年   135篇
  1998年   72篇
  1997年   64篇
  1996年   44篇
  1995年   33篇
  1994年   45篇
  1993年   21篇
  1992年   28篇
  1991年   24篇
  1990年   31篇
  1989年   22篇
  1988年   23篇
  1987年   14篇
  1986年   17篇
  1985年   15篇
  1984年   9篇
  1983年   5篇
  1982年   4篇
  1981年   5篇
  1979年   6篇
  1978年   4篇
  1977年   13篇
  1976年   6篇
  1973年   2篇
  1970年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Aims: Bone marrow (BM) biopsies of some mucosa‐associated lymphoid tissue (MALT) lymphoma patients show scattered or small clusters of CD20+ cells without definite lesions (subtle CD20 positivity). The aim of this study was to evaluate the clinical significance of BM involvement and subtle CD20 positivity in 122 patients diagnosed with MALT lymphoma. Methods and results: Patients were divided into three categories: BM involvement [BM(+)], subtle CD20 positivity, and no BM involvement [BM(?)]. Eleven (9%) showed BM involvement, and 17 (14%) showed subtle CD20 positivity. BM(+) patients had significantly worse progression‐free survival (PFS) than BM(?) patients [hazard ratio (HR) 6.25, P = 0.01], but there was no significant difference between subtle CD20 positivity and BM(?) patients. Patients with >30 CD3+ cells among 100 nucleated cells in the areas with increased numbers of CD3+ cells had significantly worse PFS than those with <15 CD3+ cells (HR 5.49, P = 0.02). BM(+) patients with >30 CD3+ cells had worse PFS than those with ≤30 CD3+ cells (P = 0.029), with an extent of BM(+) involvement of >10% positively correlating with >30 CD3+ cells (P = 0.015). Conclusions: Patients with BM(+) MALT lymphoma showed significantly worse PFS than those with subtle CD20 positivity and BM(?) MALT lymphoma, but the PFS of patients with subtle CD20 positivity MALT lymphoma was not significantly different from that of those with BM(?) MALT lymphoma. Increased numbers of BM T cells in MALT lymphoma patients might be suggestive of a worse prognosis.  相似文献   
102.
103.
PurposeThis study investigated the surgical outcomes of canalicular trephination combined with endoscopic dacryocystorhinostomy (DCR) in patients with a distal or common canalicular obstruction. It also identified the factors affecting surgical success rates associated with this technique.MethodsWe retrospectively reviewed the medical records of 57 patients (59 eyes) in whom a canalicular obstruction was encountered during endoscopic DCR. All patients were treated with endoscopic DCR, followed by canalicular trephination and silicone tube placement. The surgical outcome was categorized as a functional success according to the patient''s subjective assessment of symptoms, including epiphora, and as an anatomical success according to a postoperative nasolacrimal duct irrigation test. Surgical success rates were compared based on age, sex, location of the obstruction, number of silicone tubes, and experience of the surgeon.ResultsFunctional success was achieved in 55 of 59 eyes (93%) at one month, 50 eyes (84%) at three months, and 46 eyes (78%) at six months. Anatomical success was achieved in 58 of 59 eyes (98%) at one month, 52 eyes (88%) at three months, and 50 eyes (84%) at six months. There was a statistically significant difference in surgical outcome according to the experience of the surgeon. The anatomical success rate at the six-month follow-up exam was 95.4% in the >5 years of experience group, and 53.3% in the <5 years of experience group (p = 0.008, Pearson chi-square test).ConclusionsThe success rate of canalicular trephination combined with endoscopic DCR in patients with a distal or common canalicular obstruction decreased gradually during the six-month follow-up period. In particular, patients undergoing procedures with experienced surgeons tended to show excellent surgical outcomes at the six-month follow-up exam.  相似文献   
104.
105.
正The ascending reticular activating system(ARAS)plays a key role in the control of arousal and awareness for consciousness(Paus,2000;Zeman,2001;Van der Werf et al.,2002;Weiss et al.,2007;Siposan and Aliu,2014).It is well known that the ARAS originates from the reticular formation(RF)of the brainstem,and connects to the cerebral cortex via intralaminar  相似文献   
106.
Fractional radiofrequency microneedling is a novel radiofrequency technique that uses insulated microneedles to deliver energy to the deep dermis at the point of penetration without destruction of the epidermis. It has been used for the treatment of various dermatological conditions including wrinkles, atrophic scars and hypertrophic scars. There have been few studies evaluating the efficacy of fractional radiofrequency microneedling in the treatment of acne, and none measuring objective parameters like the number of inflammatory and non‐inflammatory acne lesions or sebum excretion levels. The safety and efficacy of fractional radiofrequency microneedling in the treatment of acne vulgaris was investigated. In a prospective clinical trial, 25 patients with moderate to severe acne were treated with fractional radiofrequency microneedling. The procedure was carried out three times at 1‐month intervals. Acne lesion count, subjective satisfaction score, sebum excretion level and adverse effects were assessed at baseline and at 4, 8 and 12 weeks after the first treatment as well as 4, 8 and 12 weeks after the last treatment. Number of acne lesions (inflammatory and non‐inflammatory) decreased. Sebum excretion and subjective satisfaction were more favorable at every time point compared with the baseline values (< 0.05). Inflammatory lesions responded better than non‐inflammatory lesions (P < 0.05). Adverse effects such as pinpoint bleeding, pain and erythema were noted, but were transient and not severe enough to stop treatment. Fractional radiofrequency microneedling is a safe and effective treatment for acne vulgaris.  相似文献   
107.
Kaposi’s sarcoma (KS) is a vascular tumor, and KS spindle cells express endothelial-cell-specific markers. Generally, it is believed that KS originates from endothelial cells. However, as various mesodermal-derived tissue markers are also expressed in KS spindle cells, the exact origin of KS still needs to be elucidated. Here, Kaposi’s sarcoma-associated herpesvirus (KSHV) was used to infect human mesenchymal stem cells derived from bone marrow (hMSC-bm), and we investigated the angiogenic properties of these cells, which are one of the most important pathologic features of KS. KSHV-infected hMSC-bm showed latent infection and increased tube formation activity in vitro. In addition, the expression of endothelial-cell-specific markers and a growth factor that affects the angiogenesis of endothelial cells was induced in KSHV-infected cells. This study suggests that human mesenchymal stem cells might have important roles in KS pathogenesis.  相似文献   
108.
109.
We present a case report to remind surgeons of this unusual complication that can occur in any surgery, even posterior cervical spine surgery under general anesthesia and discuss its causes, treatment methods, and the follow-up results in the literature. The peripheral Tapia''s syndrome is a rare complication of anesthetic airway management. Main symptoms are hoarseness of voice and difficulty of tongue movement. Tapia''s syndrome after endotracheal general anesthesia is believed to be due to pressure neuropathy of the vagus nerve and the hypoglossal nerve caused by the endotracheal tube. To our knowledge, no report has been published or given an explanation for Tapia''s syndrome after posterior cervical spine surgery. Two patients who underwent posterior cervical surgery complained hoarseness and tongue palsy postoperatively. There is no direct anatomical relation between the operation, the vagus nerves and the hypoglossal nerves, and there is no record of displacement or malposition of the endotracheal tube. After several months, all symptoms are resolved. To avoid this problem in posterior cervical spine surgery, we suggest paying special attention to the position of the endotracheal tube to avoid excessive neck flexion before and during the positioning of the patient.  相似文献   
110.
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