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   1409229篇
  免费   93853篇
  国内免费   2049篇
耳鼻咽喉   22460篇
儿科学   46693篇
妇产科学   43388篇
基础医学   213340篇
口腔科学   38403篇
临床医学   114057篇
内科学   277677篇
皮肤病学   32700篇
神经病学   108863篇
特种医学   55514篇
外国民族医学   366篇
外科学   216975篇
综合类   27003篇
现状与发展   1篇
一般理论   305篇
预防医学   97066篇
眼科学   34470篇
药学   102228篇
  1篇
中国医学   2556篇
肿瘤学   71065篇
  2018年   12011篇
  2015年   14697篇
  2014年   19726篇
  2013年   29238篇
  2012年   37074篇
  2011年   39260篇
  2010年   24762篇
  2009年   23699篇
  2008年   38514篇
  2007年   41269篇
  2006年   42293篇
  2005年   41071篇
  2004年   39380篇
  2003年   36985篇
  2002年   35413篇
  2001年   58867篇
  2000年   60304篇
  1999年   51526篇
  1998年   15304篇
  1997年   13895篇
  1996年   14524篇
  1995年   13955篇
  1994年   13347篇
  1993年   12361篇
  1992年   42556篇
  1991年   41689篇
  1990年   41107篇
  1989年   39816篇
  1988年   37121篇
  1987年   36420篇
  1986年   34701篇
  1985年   32994篇
  1984年   24872篇
  1983年   21586篇
  1982年   13339篇
  1981年   11823篇
  1980年   11011篇
  1979年   23490篇
  1978年   16881篇
  1977年   14499篇
  1976年   13600篇
  1975年   14940篇
  1974年   17452篇
  1973年   16878篇
  1972年   15981篇
  1971年   14789篇
  1970年   13739篇
  1969年   13395篇
  1968年   12504篇
  1967年   11026篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Is atrial fibrillation an inflammatory disorder?   总被引:2,自引:0,他引:2  
I read with great interest the excellent review on the influenceof inflammation in the pathogenesis of atrial fibrillation (AF)by Boos   相似文献   
92.
93.
94.
Thoraxtrauma     
Chest injuries can be sustained in isolation or in association with multiple injuries. Life-threatening complications may ensue because organs that are vital to survival of the organism are situated within the thoracic cavity. These complications include airway obstruction, tension pneumothorax, wide open pneumothorax, flail chest, cardiac tamponade and massive hemothorax. The mortality of patients hospitalized with chest injury can be as high as 10%. Clinical examination and awareness of the possibility of other injuries (high level of suspicion) are essential, and standard chest X-ray, ultrasound and thoracic computed tomography may also be needed for the diagnosis. The first part of this serial paper on the management of chest injuries focuses on anatomical aspects, pathophysiology and symptoms, but mainly on the indications for the standard diagnostic procedures and further high-tech examinations.  相似文献   
95.
The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors.  相似文献   
96.
OBJECTIVES: To identify and describe current women's thoughts about the menopause, hormone treatment (HT) and perceptions about breast cancer. METHODS: Between December 2004 and January 2005, 4201 postmenopausal women in seven European countries were interviewed via a standardized computer-aided telephone interview protocol. RESULTS: Almost all women reported to have experienced climacteric symptoms, and 63% of the women rated them as being severe. Only 52% of women were aware of the benefits of HT for relief of climacteric symptoms. Although 84% felt that severe symptoms should be treated, only 40% had used HT at some point in time. Thirty-four percent of the women preferring treatment with natural products did so because of the risk of breast cancer associated with HT. HT was recognized by 59% of the women as one of the most important contributors to an increased breast cancer risk. Most women received their information about HT and breast cancer risk from the media. CONCLUSIONS: This European survey reveals that the majority of women experience climacteric symptoms but that their decision whether or not to use HT is highly dependent on their concern about breast cancer risk. An increase in knowledge of the benefits and risks of HT is required for women to make appropriate decisions about hormone use.  相似文献   
97.
98.
Rehabilitative and palliative measures in the follow-up care of pancreatic cancer patients will remain the dominant medical focus as long as potentially curative measures (recurrence prophylaxis, early detection and therapy of recurrence) have failed to show a significant survival benefit. Rehabilitative measures are possible for patients undergoing potentially curative as well as palliative treatment. Their aim is to alleviate the negative effects of the cancer and its therapy, not only physically, but also psychologically, socially and vocationally. The spectrum of possible somatic handicaps ranges from metabolic disorders, malnutrition and under-nutrition, as well as gastrointestinal symptoms to pain. Assistance in coping with illness, alleviating fears and depression and strengthening compliance are the main areas which are dealt with in psycho-oncology. Assessment of vocational fitness and the capacity to work depends on tumor location, whether R0 or R1 resection has taken place, the extent of pancreas resection, accompanying illnesses, whether or not adjuvant therapy has been given, and the physical condition of the patient  相似文献   
99.
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.  相似文献   
100.
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