全文获取类型
收费全文 | 2432314篇 |
免费 | 196366篇 |
国内免费 | 8220篇 |
专业分类
耳鼻咽喉 | 31962篇 |
儿科学 | 80044篇 |
妇产科学 | 68185篇 |
基础医学 | 339400篇 |
口腔科学 | 66615篇 |
临床医学 | 220583篇 |
内科学 | 489674篇 |
皮肤病学 | 57810篇 |
神经病学 | 201757篇 |
特种医学 | 95959篇 |
外国民族医学 | 708篇 |
外科学 | 369723篇 |
综合类 | 58055篇 |
现状与发展 | 4篇 |
一般理论 | 829篇 |
预防医学 | 195049篇 |
眼科学 | 53936篇 |
药学 | 170787篇 |
6篇 | |
中国医学 | 5011篇 |
肿瘤学 | 130803篇 |
出版年
2018年 | 26467篇 |
2017年 | 20492篇 |
2016年 | 23827篇 |
2015年 | 26647篇 |
2014年 | 37559篇 |
2013年 | 56168篇 |
2012年 | 72369篇 |
2011年 | 77518篇 |
2010年 | 47014篇 |
2009年 | 45332篇 |
2008年 | 71968篇 |
2007年 | 76345篇 |
2006年 | 77591篇 |
2005年 | 75286篇 |
2004年 | 71919篇 |
2003年 | 69165篇 |
2002年 | 66229篇 |
2001年 | 118598篇 |
2000年 | 121599篇 |
1999年 | 101264篇 |
1998年 | 29838篇 |
1997年 | 26869篇 |
1996年 | 27626篇 |
1995年 | 27024篇 |
1994年 | 24867篇 |
1993年 | 23384篇 |
1992年 | 80255篇 |
1991年 | 77471篇 |
1990年 | 74393篇 |
1989年 | 70876篇 |
1988年 | 65448篇 |
1987年 | 64117篇 |
1986年 | 60260篇 |
1985年 | 57894篇 |
1984年 | 44162篇 |
1983年 | 37291篇 |
1982年 | 23106篇 |
1981年 | 20650篇 |
1980年 | 19235篇 |
1979年 | 39546篇 |
1978年 | 28312篇 |
1977年 | 23721篇 |
1976年 | 22002篇 |
1975年 | 22791篇 |
1974年 | 27098篇 |
1973年 | 26068篇 |
1972年 | 24341篇 |
1971年 | 22303篇 |
1970年 | 20820篇 |
1969年 | 19375篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
51.
M Müller J Grunewald C Olgart H?glund B Dahlén A Eklund H Stridh 《The European respiratory journal》2006,28(3):513-522
The increased number of lymphocytes in airways during an asthmatic response is believed to be the result of increased recruitment of these cells. However, it is possible that a decreased apoptotic rate could also contribute to the increased number. The aim of the present study was to investigate whether allergen airway provocation influences the apoptotic phenotype of lung and peripheral blood lymphocytes (PBL) in subjects with atopic asthma. Bronchoalveolar lavage (BAL) lymphocytes and PBL from 12 asthmatic subjects previously challenged with allergen (n = 7) or saline (n = 5) were exposed to the apoptotic stimulus tributyltin (TBT) in vitro and assayed for apoptosis. Airway allergen provocation resulted in decreased sensitivity of BAL lymphocytes to TBT-induced apoptosis, with 42.2% (range 33.9-62.5%) apoptotic cells before challenge versus 23.5% (range 15.3-42.4%) after challenge, while PBL were unaffected. The increased apoptosis resistance correlated with higher numbers of Bcl-2-expressing lymphocytes. Interestingly, baseline caspase-3-like activity was significantly elevated in viable BAL lymphocytes compared with viable PBL, and was unaltered by allergen exposure. In conclusion, allergen inhalation renders bronchoalveolar lavage lymphocytes more resistant to apoptosis while peripheral blood lymphocytes were not influenced at all, indicating that the apoptotic phenotype of airway lymphocytes may play a role in asthmatic inflammation. 相似文献
52.
K. Dahan V. Audard F. Roudot-Thoraval D. Desvaux M. Abtahi H. Mansour M. Kumal P. Lang P. Grimbert 《American journal of transplantation》2006,6(7):1725-1730
The clinical outcome and appropriate management for patients showing 'borderline changes' on allograft biopsy after renal transplantation is still controversial. In an attempt to identify predictive factors of clinical outcome of patients with such lesions, we reviewed the clinical course of 91 patients with borderline changes. Multivariate analysis revealed significant and independent effects of histological stage (i + t < or = or > 2) and time to borderline changes (< or = or > 3 months after transplant) on serum creatinine levels at 1 year from borderline changes episodes (respectively, p = 0.04 and p = 0.02) and only a significant effect of time to borderline changes on serum creatinine levels at 2 years (p = 0.005). Renal function at 1 year and 2 years as 5- and 8-year graft survival were not significantly different in the group of patients treated with antirejection therapy (T group, n = 49) compared with the untreated group (UT group, n = 42). This study strongly suggests that borderline changes with histological score (i + t) > 2 and late episodes of borderline changes should be considered to be of poor prognosis. 相似文献
53.
54.
D Monnier† C Vidal‡ L Martin§ A Danzon¶ F Pelletier† E Puzenat† MP Algros†† D Blanc† R Laurent† PH Humbert† F Aubin† 《Journal of the European Academy of Dermatology and Venereology》2006,20(10):1237-1242
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating. 相似文献
55.
56.
57.
Parupudi V J Sriram Guduru V Rao Nageshwar D Reddy 《Indian journal of gastroenterology》2006,25(1):39-41
Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia. 相似文献
58.
59.
60.