全文获取类型
收费全文 | 2051825篇 |
免费 | 145281篇 |
国内免费 | 3972篇 |
专业分类
耳鼻咽喉 | 30309篇 |
儿科学 | 60174篇 |
妇产科学 | 56784篇 |
基础医学 | 290373篇 |
口腔科学 | 62442篇 |
临床医学 | 177966篇 |
内科学 | 396799篇 |
皮肤病学 | 45408篇 |
神经病学 | 162572篇 |
特种医学 | 80879篇 |
外国民族医学 | 501篇 |
外科学 | 321143篇 |
综合类 | 45490篇 |
现状与发展 | 7篇 |
一般理论 | 674篇 |
预防医学 | 144021篇 |
眼科学 | 49062篇 |
药学 | 156133篇 |
7篇 | |
中国医学 | 4534篇 |
肿瘤学 | 115800篇 |
出版年
2018年 | 19019篇 |
2016年 | 16889篇 |
2015年 | 19029篇 |
2014年 | 26323篇 |
2013年 | 39879篇 |
2012年 | 52927篇 |
2011年 | 55920篇 |
2010年 | 33197篇 |
2009年 | 32019篇 |
2008年 | 54011篇 |
2007年 | 57843篇 |
2006年 | 58779篇 |
2005年 | 56892篇 |
2004年 | 55186篇 |
2003年 | 53235篇 |
2002年 | 52372篇 |
2001年 | 100918篇 |
2000年 | 103865篇 |
1999年 | 87696篇 |
1998年 | 22916篇 |
1997年 | 20671篇 |
1996年 | 20182篇 |
1995年 | 19058篇 |
1994年 | 17736篇 |
1993年 | 16495篇 |
1992年 | 67856篇 |
1991年 | 65636篇 |
1990年 | 64270篇 |
1989年 | 62529篇 |
1988年 | 57930篇 |
1987年 | 56791篇 |
1986年 | 53902篇 |
1985年 | 51548篇 |
1984年 | 38085篇 |
1983年 | 32542篇 |
1982年 | 18777篇 |
1981年 | 16978篇 |
1979年 | 36084篇 |
1978年 | 25399篇 |
1977年 | 22105篇 |
1976年 | 19790篇 |
1975年 | 22271篇 |
1974年 | 26567篇 |
1973年 | 25646篇 |
1972年 | 24399篇 |
1971年 | 22852篇 |
1970年 | 21744篇 |
1969年 | 20682篇 |
1968年 | 19272篇 |
1967年 | 17324篇 |
排序方式: 共有10000条查询结果,搜索用时 0 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.
Katharine R. Owen Mollie Donohoe Sian Ellard Andrew T. Hattersley 《Diabetic medicine》2003,20(10):823-827
Background Familial partial lipodystrophy (FPLD) is a monogenic form of diabetes characterised by a dominantly inherited disorder of adipose tissue associated with the loss of subcutaneous fat from the limbs and trunk, with excess fat deposited around the face and neck. The lipodystrophy causes severe insulin resistance, resulting in acanthosis nigricans, diabetes, dyslipidaemia, and increased risk of cardiovascular disease. Preliminary results from animals and man suggest that increasing subcutaneous fat by treatment with thiazolidinediones should improve insulin resistance and the associated features of this syndrome. Case report We report a 24-year-old patient with FPLD caused by a mutation in the LMNA gene (R482W) treated with 12 months of rosiglitazone. Subcutaneous fat increased following rosiglitazone treatment as demonstrated by a 29% generalised increase in skin-fold thickness. Leptin levels increased from 5.8 to 11.2 ng/ml. Compared with treatment on Metformin, there was an increase in insulin sensitivity (HOMA S% 17.2–31.6) but no change in glycaemic control. The lipid profile worsened during the follow-up period. Conclusion This initial case suggests that, for modification of cardiovascular risk factors, there are no clear advantages in treating patients with FPLD with rosiglitazone despite increases in subcutaneous adipose tissue. Larger series will be needed to identify moderate beneficial effects and treatment may be more effective in patients with generalised forms of lipodystrophy. 相似文献
53.
M Ugras† G Kocak† H Ozcan‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(9):1126-1128
Neu-Laxova syndrome (NLS) is a rare autosomal recessive syndrome, characterized by severe intrauterine growth retardation (IUGR), microcephaly, abnormal brain development, oedema and ichthyosis. It was first reported in 1971 by Neu et al. (Pediatrics 47: 610-612) and since then no more than 60 cases have been reported. A newborn girl delivered from a 29-year-old healthy mother was admitted to hospital with a thick membrane covering her body and dismorphic appearance. The diagnosis of NLS was made according to characteristic features. The syndrome is known to have a poor prognosis and the baby lived for 9 weeks. This case is one of the longest living cases of NLS and the fourth case reported from Turkey. 相似文献
54.
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
55.
Weiping Ren Bin Wu Xin Peng Jing Hua Hsiao-Nan Hao Paul H Wooley 《Journal of orthopaedic research》2006,24(8):1575-1586
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response. 相似文献
56.
57.
AIM: The intention was to investigate cerebrospinal fluid pressure (CSFP) and volume of cerebrospinal fluid (CSF) drained during and after thoracic- and thoracoabdominal aneurysm repair. The findings were related to the occurrence of postoperative neurologic deficits. METHODS: Twenty-nine patients (12 with thoracic and 17 with thoracoabdominal aortic aneurysm) were operated without shunting or extracorporeal circulation. For monitoring of CSFP an intrathecal catheter was placed in all patients. The volume of CSF withdrawn intraoperatively, on the day of operation as well as on the 1st and 2nd postoperative day was recorded. RESULTS: Twenty-six patients had no postoperative neurologic sequelae. One patient had postoperative paraplegia while 2 had paraparesis. The three patients with neurologic sequelae had higher CSFP intraoperatively than those without neurologic symptoms (P=0.04). Median CSFP during aortic cross-clamping was 19 mmHg and 10 mmHg and the median volumes of CSF drained on the day of operation 210 and 85 mL in the two groups, respectively. There was a significant positive correlation between CSFP and central venous pressure. CONCLUSIONS: A higher intraoperative CSFP was observed in patients with neurologic sequelae following thoracic- and thoracoabdominal aneurysm repair. Further, there was a tendency of higher volumes of CSF drained in this group of patients. Although, the series is too small to allow firm conclusions, it supports the view that CSFP monitoring and drainage is beneficial during thoracic- and thoracoabdominal aneurysm repair. 相似文献
58.
59.
60.