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   5899篇
  免费   684篇
  国内免费   34篇
耳鼻咽喉   77篇
儿科学   110篇
妇产科学   85篇
基础医学   664篇
口腔科学   519篇
临床医学   595篇
内科学   1129篇
皮肤病学   37篇
神经病学   360篇
特种医学   251篇
外科学   1201篇
综合类   149篇
一般理论   3篇
预防医学   519篇
眼科学   96篇
药学   229篇
中国医学   4篇
肿瘤学   589篇
  2023年   38篇
  2022年   49篇
  2021年   98篇
  2020年   84篇
  2019年   123篇
  2018年   155篇
  2017年   115篇
  2016年   128篇
  2015年   121篇
  2014年   210篇
  2013年   255篇
  2012年   327篇
  2011年   336篇
  2010年   234篇
  2009年   195篇
  2008年   295篇
  2007年   345篇
  2006年   270篇
  2005年   272篇
  2004年   248篇
  2003年   227篇
  2002年   222篇
  2001年   203篇
  2000年   212篇
  1999年   173篇
  1998年   86篇
  1997年   71篇
  1996年   58篇
  1995年   64篇
  1994年   59篇
  1993年   37篇
  1992年   109篇
  1991年   115篇
  1990年   83篇
  1989年   70篇
  1988年   85篇
  1987年   104篇
  1986年   67篇
  1985年   75篇
  1984年   55篇
  1983年   61篇
  1982年   35篇
  1981年   41篇
  1980年   35篇
  1979年   49篇
  1978年   47篇
  1974年   28篇
  1973年   45篇
  1972年   26篇
  1970年   25篇
排序方式: 共有6617条查询结果,搜索用时 15 毫秒
31.
We conducted an incidence study to determine the occurrence rates of clear cell adenocarcinoma (CCAC) of the vagina and cervix in young women (born in 1940 and thereafter), and a case-series analysis, focusing on the maternal history of pregnancy and delivery and in-utero exposure to diethylstilbestrol (DES). Overall, 10 cases of CCAC had been listed in the files of the Connecticut State Tumor Registry prior to the study, and each of the 10 cases were confirmed as valid. In addition, another 10 cases, all previously undetected, were found after the tissue slides of young women listed as having other cancers of the vagina and cervix were reviewed by expert pathologists, suggesting that prior estimates of the incidence rate for CCAC must be misleading unless special efforts are taken to identify undetected cases. The incidence rates of vaginal CCAC (11 cases total) were highest in 1975-1979, and decreased slightly during 1980-1982. In the cervix (nine cases total), the rate increased consistently since 1970. History of in-utero exposure to diethylstilbestrol was obtained for five of eight vaginal cases and four of eight cervical cases of CCAC. In all nine cases, exposure to diethylstilbestrol was associated with a history of bleeding during the pregnancy or prior miscarriage. We conclude that the finding of stable (or rising) incidence rates for CCAC occurring nearly 30 years after the marked decrease in diethylstilbestrol sales emphasizes the need for continued clinical and epidemiologic studies of the etiology and clinical course of CCAC.  相似文献   
32.
33.
34.
A 29-year-old white woman had short limbs, hyperextendable joints, fine skin and body hair, anergy to common skin test antigens, subnormal lymphocyte response to phytohemagglutinin, and increased numbers of natural killer cells, characteristic of cartilage-hair hypoplasia, an autosomal, recessively inherited disorder found in America mainly among the old-order Amish. Her forearm skin was hyperextendable and numerous verrucae were present on the digits of her hands. A skin biopsy from hyperextendable skin showed ovoid, 10- to 20-micron bodies in the papillary dermis. Ultrastructurally, the bodies were interpreted as abnormal elastic fibers.  相似文献   
35.
36.
37.
Background: Many patients treated for breast cancer with radiotherapy will survive their disease and be at risk for treatment-related sarcoma for many years. Methods: In order to identify patients with post-treatment sarcoma and define this disease, we examined the records of 99 patients treated for sarcoma with a history of antecedent breast carcinoma. Of these patients, 51 were felt to have a sarcoma unrelated to breast cancer treatment and 48 were felt to have a treatment-related sarcoma (secondary to lymphedema and/or radiation). Results: Lymphangiosarcoma of the extremity was the most common histologic subtype of post-treatment sarcoma, accounting for 22 of 48 cases (46%). Twenty-six patients (54%) developed nonlymphangiosarcoma post-treatment sarcoma; all of these were radiation-associated sarcomas. The median latency interval between the diagnosis of breast cancer and the development of sarcoma was 11 years (range 4–44) and was not different between the two groups. However, patients with nonlymphangiosarcoma were significantly younger when diagnosed with breast cancer than were those with lymphangiosarcoma of the extremity (median 43 vs. 51 years, p<0.001). The survival of all 48 patients was poor: 5-year survival was 29%. Five-year survival of patients with other types of post-treatment sarcoma was just as poor as those with lymphangiosarcoma of the extremity (30% vs. 28%, p=0.98). Conclusions: Patients who develop sarcoma after treatment for breast cancer have a poor prognosis whether it occurs as Stewart-Treves syndrome or other types of post-treatment sarcoma. Younger patients may be at higher risk than are older patients for the development of nonlymphangiosarcoma post-treatment sarcoma.Presented at the 46th Annual Cancer Symposium of the Society of Surgical Oncology, Los Angeles, March 18–21, 1993.  相似文献   
38.
Although lipomas are relatively common and found in most anatomical sites, we are not aware of any previous reports of lipomas arising between the two layers of the deep temporal fascia above the zygomatic arch. This is surprising because a fat pad is seen and used during surgery in this area to protect the frontal branch of the facial nerve. This case highlights the importance of understanding the anatomy of this region, because lipomas can potentially arise in any of three fat pads laying near the facial nerve in this area.  相似文献   
39.
40.
Chordoma is a rare tumor, arising from notochord remnants, which usually occurs in the axial skeleton and rarely metastasizes. Although there have been 3 previous reports of metastatic disease to the facial bones from sacrococcygeal chordoma, this is the first to describe spread to the mandible from a vertebral primary chordoma.  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