全文获取类型
收费全文 | 3004篇 |
免费 | 188篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 191篇 |
妇产科学 | 69篇 |
基础医学 | 425篇 |
口腔科学 | 28篇 |
临床医学 | 214篇 |
内科学 | 580篇 |
皮肤病学 | 86篇 |
神经病学 | 126篇 |
特种医学 | 107篇 |
外科学 | 324篇 |
综合类 | 172篇 |
预防医学 | 285篇 |
眼科学 | 52篇 |
药学 | 261篇 |
中国医学 | 46篇 |
肿瘤学 | 189篇 |
出版年
2023年 | 22篇 |
2022年 | 51篇 |
2021年 | 106篇 |
2020年 | 52篇 |
2019年 | 47篇 |
2018年 | 77篇 |
2017年 | 52篇 |
2016年 | 65篇 |
2015年 | 85篇 |
2014年 | 112篇 |
2013年 | 127篇 |
2012年 | 192篇 |
2011年 | 212篇 |
2010年 | 134篇 |
2009年 | 87篇 |
2008年 | 155篇 |
2007年 | 164篇 |
2006年 | 163篇 |
2005年 | 138篇 |
2004年 | 98篇 |
2003年 | 99篇 |
2002年 | 85篇 |
2001年 | 90篇 |
2000年 | 89篇 |
1999年 | 62篇 |
1998年 | 17篇 |
1997年 | 12篇 |
1996年 | 26篇 |
1995年 | 22篇 |
1993年 | 17篇 |
1992年 | 43篇 |
1991年 | 44篇 |
1990年 | 42篇 |
1989年 | 47篇 |
1988年 | 40篇 |
1987年 | 24篇 |
1986年 | 24篇 |
1985年 | 28篇 |
1984年 | 15篇 |
1983年 | 14篇 |
1979年 | 24篇 |
1978年 | 15篇 |
1977年 | 13篇 |
1975年 | 13篇 |
1974年 | 12篇 |
1973年 | 21篇 |
1972年 | 13篇 |
1971年 | 17篇 |
1970年 | 16篇 |
1969年 | 16篇 |
排序方式: 共有3201条查询结果,搜索用时 15 毫秒
1.
2.
Emmi Helle Aldo Córdova-Palomera Tiina Ojala Priyanka Saha Praneetha Potiny Stefan Gustafsson Erik Ingelsson Michael Bamshad Deborah Nickerson Jessica X. Chong University of Washington Center for Mendelian Genomics Euan Ashley James R. Priest 《Genetic epidemiology》2019,43(2):215-226
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes. 相似文献
3.
The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells. 相似文献
4.
5.
A case of Ewing's tumour of rib presenting as chest mass is reported. The role of computed tomography and chest ultrasound in evaluating such patients is discussed along with a brief review of literature. 相似文献
6.
V Saha S Love T Eden P Micallef-Eynaud G MacKinlay 《Archives of disease in childhood》1993,68(6):771-774
The duration of symptoms before diagnosis (lag time) was defined for 184 of 236 children diagnosed as having a malignancy at the Royal Hospital for Sick Children, Edinburgh for the time period January 1982 until December 1990. The natural logarithm of the lag time was correlated with age, gender, diagnostic group, white cell count in acute leukaemia, clinical stage of disease in solid tumours, and event free survival. Age was significantly associated with lag time, older children presenting later. In the diagnostic groups, mean lag time ranged from 2.8 weeks in nephroblastoma to 13.3 weeks for brain tumours. Diagnostic group was predictive for lag time after adjustment for age, with for example, a significantly longer lag time for those with brain tumours. However lag time was not predictive of event free survival and it is likely that lag time has other major determinants. When compared with previous studies, there also appears to be a regional variation in lag time for diagnostic groups. It seems likely that this is a reflection of geographical difference in the structure of health systems and is therefore yet another important determinant. 相似文献
7.
8.
Dysfunction of neutrophils in patients infected with human immunodeficiency virus is at least partly responsible for secondary microbial diseases in these individuals, including invasive gastrointestinal (GI) candidiasis. Immunoregulatory disturbances associated with the development of AIDS in human immunodeficiency virus-infected patients exacerbates Candida albicans infection of the upper GI tract and frequently leads to oropharyngeal and esophageal candidiasis. In this article, we present the first report of a murine model of invasive GI candidiasis associated with an AIDS-related murine immunodeficiency syndrome that results from infection of C57BL/6 mice with a previously described retrovirus complex (LP-BM5). Mice of the inbred strain were infected with C. albicans by oral-intragastric inoculation as infants and with the retrovirus by the intraperitoneal route 30 days later. Control mice of the same strain were infected with C. albicans as above and subsequently infected with the avirulent, ecotropic helper virus (MBI-5). Animals were killed 90 days after retroviral challenge. Total and differential blood cell counts, CD4+ T-cell counts in the spleen, and the histopathology of the gastric mucosa of experimental and control animals were determined. The virulent LP-BM5-infected animals developed murine AIDS and showed eruptive and suppurative lesions, with associated C. albicans mainly in regions of the cardial-atrium fold of the stomach. Well-defined abscesses with entrapped C. albicans hyphae were observed in the region of the cardial-atrium fold of control mice. A significant increase in the number of C. albicans CFU in homogenized and plated segments of the GI tract was recognized in mice with murine AIDS versus the control animals. The murine model of GI candidiasis reported here permits examination of the nature of C. albicans interaction with the gastric mucosa both in the immunocompetent host under conditions in which the yeast exists predominantly as a commensal organism and in the immunosuppressed host during progressive stages of AIDS induced by a retroviral infection. 相似文献
9.
Abhishek Srivastava Anirban Ghosh Somnath Saha V. P. Saha Debdulal Chakraborty 《Indian journal of otolaryngology and head and neck surgery》2007,59(4):322-326
38 cases of sarcoma of head and neck region were analysed in a retrospective way in relation to age, anatomic location, histological,
clinical profile, and surgical approaches. Compared to other types of head and neck neoplasms, such as squamous cell carcinoma,
soft tissue sarcomas have low rates of regional metastases. However the biological behaviour of soft tissue sarcoma is more
aggressive specially in paediatric age group. In the present series, CT scan was considered as the primary modality of investigation.
Surgery generally has been recommended as the primary method of treatment for achieving local control, except in those high-grade
tumours arising in sites not amenable to resection. 3-year and 5-year survival rates in this present series 50% and 31.6%
respectively. 相似文献
10.
Y Leskinen JP Salenius T Lehtim?ki H Huhtala H Saha 《American journal of kidney diseases》2002,40(3):472-479
BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF. 相似文献