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   1264篇
  免费   38篇
  国内免费   1篇
耳鼻咽喉   14篇
儿科学   95篇
妇产科学   101篇
基础医学   97篇
口腔科学   56篇
临床医学   93篇
内科学   253篇
皮肤病学   24篇
神经病学   51篇
特种医学   33篇
外科学   216篇
综合类   13篇
预防医学   26篇
眼科学   21篇
药学   25篇
中国医学   6篇
肿瘤学   179篇
  2024年   2篇
  2023年   11篇
  2022年   15篇
  2021年   39篇
  2020年   41篇
  2019年   45篇
  2018年   38篇
  2017年   28篇
  2016年   36篇
  2015年   42篇
  2014年   42篇
  2013年   64篇
  2012年   96篇
  2011年   80篇
  2010年   57篇
  2009年   68篇
  2008年   91篇
  2007年   98篇
  2006年   95篇
  2005年   82篇
  2004年   85篇
  2003年   64篇
  2002年   50篇
  2001年   8篇
  2000年   6篇
  1999年   5篇
  1998年   1篇
  1997年   4篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1992年   4篇
  1991年   2篇
  1990年   1篇
排序方式: 共有1303条查询结果,搜索用时 15 毫秒
991.
Since a large variety of disorders may lead to lymph node enlargement determining the cause of peripheral lymphadenopathy (LAP) in children can be difficult. This retrospective study evaluated 200 children who were admitted to an Oncology-Hematology department because of lymphadenopathy and aimed to determine the clinical and laboratory findings that were valuable for differential diagnosis. A specific cause for lymphadenopathy was documented in 93 (46.5%) cases. One hundred forty (70%) children were classified as having a benign cause for lymph node enlargements. Fourteen (10%) of these cases underwent an excisional lymph node biopsy, and histopathological examination showed a reactive hyperplasia. Sixty (30%) cases were classified as having a malignant disease-causing lymphadenopathy. In terms of differential diagnosis, some associated systemic symptoms, physical findings, and laboratory investigations showed significant difference between benign and malignant lymphadenopathy groups. The following findings were determined as being important to alert the physician about the probability of a malignant disorder: location of the lymphadenapathy (supraclavicular and posterior auricular), duration of the lymph node enlargement (>4 weeks), size of the lymph node (>3 cm), abnormal complete blood cell findings, abnormalities in chest X-ray, and abdominal ultrasonography.  相似文献   
992.
993.
As the management of breast cancer evolves toward less invasive treatments, the next step is the possibility of removing the primary tumor without surgery. The most promising of the noninvasive ablation techniques is radiofrequency ablation, which uses frictional heating that is caused when ions in the tissue attempt to follow the changing directions of a high-frequency alternating current. Three pilot studies, including an ongoing study at M.D. Anderson Cancer Center, have demonstrated that radiofrequency ablation is effective for the destruction of small primary breast cancers. The most important factorfor successful radiofrequency ablation is accuracy of the ultrasound evaluation, which is used to estimate tumor size, localize the tumor for treatment, and monitor the progress of the ablation. A study in preparation at M.D. Anderson will determine whether the use of radiofrequency ablation alone for the local treatment of primary breast cancer will result in outcomes equivalent to those obtained with breast conservation therapy.  相似文献   
994.
995.
996.
Background Our goal was to evaluate the role of breast-conservation therapy in early-stage breast cancer patients with a family history (FH) of breast cancer. Methods Between 1970 and 1994, 1324 female patients with breast cancer were treated with breast-conservation therapy at our institution. From these, we identified 985 patients with stage 0–II breast cancer and who had available information on FH status. FH was considered positive in any patient who had a relative who had been previously diagnosed with breast cancer. Disease-specific survival was calculated from the date of initial diagnosis using the Kaplan-Meier method. Results The stage distribution for the 985 patients was as follows: 0 in 65 (7%), I in 500 (51%), and II in 420 (43%). The median age was 50 years (range, 21–88), with a median follow-up time of 8.8 years (range, .25–29). The median tumor size was 1.5 cm. FH was positive in 31%. There were no significant differences in locoregional recurrence, distant recurrence, disease-specific survival, or incidence of contralateral breast cancer in patients with a positive FH versus patients with a negative FH. Conclusions Breast-conservation therapy is not contraindicated in early-stage breast cancer patients with a positive FH.  相似文献   
997.
The autopodia of proximal limbs as well as the proximal growth plates of the tibia of newborn nu/nu including super nu/nu, nu/+ and +/+ mice were studied. No differences in the ossification of proximal limb autopodia (regarding the distribution of alkaline phosphatase, acid phosphatase or glycosaminoglycans) were observed in mice of genotypes studied. On the other hand, a thinner proximal tibial growth plate characterizes one-month-old nu/nu mice, and also the architecture and alkaline phosphatase pattern were altered. The results suggest a postnatal secondary effect of the nu/nu genotype on skeletal development.  相似文献   
998.
Aim: To investigate the effect of intratunical instillation of bupivacaine and methylprednisolone for scrotal pain, swelling and peritesticular fibrosis due to testicular sperm retrieval procedures. Methods: A total of 65 patients were randomly divided into two groups. In the instillation group (GI), 34 patients were administered 2.5 mL of 0.5 % bupivacaine combined with 10 mg/mL methylprednisolone before closure of the tunica vaginalis. In the control group (GC), 31 patients only received analgesics postoperatively by intramuscular route. The pain (by visual analogue scale, VAS) and duration of pain-free period after surgery between the two groups were evaluated at 2 and 4 h and at days 2 and 7 postoperatively. Results: The mean pain scores were significantly lower in the GI than in the GC group at 2 and 4 h after surgery (P<0.05 and P<0.01, respectively). The mean duration of pain free interval after the procedure was 47.8±16.9 (12-72) h in GI, which was significantly longer than that in GC [(9.9±3.6  相似文献   
999.
Background: Chest wall recurrence (CWR) after mastectomy often forecasts a grim prognosis. Predictors of outcome after CWR, however, are not clear.Methods: From 1988 to 1998, 130 patients with isolated CWRs were seen at our center. Clinicopathologic factors were studied by univariate and multivariate analyses for distant metastasis–free survival after CWR. The median post-CWR follow-up was 37 months.Results: Initial nodal status was the strongest predictor of outcome by univariate analysis. Other significant factors included initial T4 disease, primary lymphovascular invasion, treatment of the primary tumor with neoadjuvant therapy or radiation, time to CWR >24 months, and treatment for CWR (surgery, radiation, or multimodality therapy). Multivariate analysis also found initial nodal status to have the greatest effect; time to CWR and use of radiation for CWR were also independent predictors. Three groups of patients were identified. Low risk was defined by initial node-negative disease, time to CWR >24 months, and radiation for CWR; intermediate risk had one or two favorable features; and high risk had none. The median distant metastasis–free survival after CWR was significantly different among these groups (P < .0001).Conclusions: Patients with CWR are a heterogeneous population. Patients with initial node-negative disease who develop CWR after 24 months have an optimistic prognosis, especially if they are treated with radiation.  相似文献   
1000.
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