全文获取类型
收费全文 | 4304篇 |
免费 | 264篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 100篇 |
妇产科学 | 97篇 |
基础医学 | 733篇 |
口腔科学 | 269篇 |
临床医学 | 411篇 |
内科学 | 909篇 |
皮肤病学 | 60篇 |
神经病学 | 450篇 |
特种医学 | 72篇 |
外科学 | 404篇 |
综合类 | 28篇 |
一般理论 | 2篇 |
预防医学 | 408篇 |
眼科学 | 73篇 |
药学 | 255篇 |
中国医学 | 17篇 |
肿瘤学 | 243篇 |
出版年
2024年 | 8篇 |
2023年 | 54篇 |
2022年 | 103篇 |
2021年 | 184篇 |
2020年 | 129篇 |
2019年 | 153篇 |
2018年 | 158篇 |
2017年 | 119篇 |
2016年 | 138篇 |
2015年 | 139篇 |
2014年 | 162篇 |
2013年 | 221篇 |
2012年 | 356篇 |
2011年 | 389篇 |
2010年 | 206篇 |
2009年 | 160篇 |
2008年 | 279篇 |
2007年 | 244篇 |
2006年 | 270篇 |
2005年 | 222篇 |
2004年 | 171篇 |
2003年 | 163篇 |
2002年 | 141篇 |
2001年 | 66篇 |
2000年 | 71篇 |
1999年 | 58篇 |
1998年 | 15篇 |
1997年 | 7篇 |
1996年 | 9篇 |
1995年 | 10篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 15篇 |
1991年 | 17篇 |
1990年 | 14篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1980年 | 6篇 |
1974年 | 3篇 |
1972年 | 4篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
1931年 | 3篇 |
1930年 | 3篇 |
排序方式: 共有4584条查询结果,搜索用时 0 毫秒
11.
Carolyn A Chew-Graham Karina Lovell Chris Roberts Robert Baldwin Michael Morley Alistair Burns David Richards Heather Burroughs 《The British journal of general practice》2007,57(538):364-370
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients. 相似文献
12.
Taylor S Thordarson DS Maxfield L Fedoroff IC Lovell K Ogrodniczuk J 《Journal of consulting and clinical psychology》2003,71(2):330-338
The authors examined the efficacy, speed, and incidence of symptom worsening for 3 treatments of posttraumatic stress disorder (PTSD): prolonged exposure, relaxation training, or eye movement desensitization and reprocessing (EMDR; N = 60). Treaments did not differ in attrition, in the incidence of symptom worsening, or in their effects on numbing and hyperarousal symptoms. Compared with EMDR and relaxation training, exposure therapy (a) produced significantly larger reductions in avoidance and reexperiencing symptoms, (b) tended to be faster at reducing avoidance, and (c) tended to yield a greater proportion of participants who no longer met criteria for PTSD after treatment. EMDR and relaxation did not differ from one another in speed or efficacy. 相似文献
13.
Amo L Fargallo JA Martínez-Padilla J Millán J López P Martín J 《Parasitology research》2005,96(6):413-417
We describe the blood and intestinal parasites in the Ocellated lizard, Lacerta lepida, examining the factors that determine the prevalence and intensity of infection of haemogregarines, and the prevalence of coccidia and nematodes. In relation to haemogregarines, no juveniles were detected as being infected, whereas 71.7 % of adults were infected. The prevalence of infection was positively related to the size of the adults. There were no differences between seasons or sexes in the prevalence or intensity of infection in adults. There were no significant differences in the prevalence of infection by nematodes between ages or sexes, nor in relation to the size of adult lizards, but adult lizards excreting coccidian oocysts tend to be smaller. During the mating period, reproductive activities lead to a decrease in the body condition. However, neither the intensity of haemogregarines infection nor the prevalence of intestinal parasites was related to the lizards body condition. 相似文献
14.
Raoud Marayati Laura V. Bownes Colin H. Quinn Nikita Wadhwani Adele P. Williams Hooper R. Markert Venkatram Atigadda Jamie M. Aye Jerry E. Stewart Karina J. Yoon Elizabeth A. Beierle 《Journal of pediatric surgery》2021,56(6):1165-1173
IntroductionThe poor therapeutic efficacy seen with current treatments for neuroblastoma may be attributed to stem cell-like cancer cells (SCLCCs), a subpopulation of cancer cells associated with poor prognosis and disease recurrence. Retinoic acid (RA) is a differentiating agent used as maintenance therapy for high-risk neuroblastoma but nearly half of children treated with RA relapse. We hypothesized that 6-Methyl-UAB30 (6-Me), a second-generation rexinoid recently developed with a favorable toxicity profile compared to RA, would reduce cancer cell stemness in human neuroblastoma patient-derived xenografts (PDXs).MethodsCells from three neuroblastoma PDXs were treated with 6-Me and proliferation, viability, motility, and cell-cycle progression were assessed. CD133 expression, sphere formation, and mRNA abundance of stemness and differentiation markers were evaluated using flow cytometry, in vitro extreme limiting dilution analysis, and real-time PCR, respectively.ResultsTreatment with 6-Me decreased proliferation, viability, and motility, and induced cell-cycle arrest and differentiation in all three neuroblastoma PDXs. In addition, 6-Me treatment led to decreased CD133 expression, decreased sphere-forming ability, and decreased mRNA abundance of Oct4, Nanog, and Sox2, indicating decreased cancer cell stemness.Conclusions6-Me decreased oncogenicity and reduced cancer cell stemness of neuroblastoma PDXs, warranting further exploration of 6-Me as potential novel therapy for neuroblastoma. 相似文献
15.
16.
17.
Millán-Rodríguez F Palou J de la Torre-Holguera P Vayreda-Martija JM Villavicencio-Mavrich H Vicente-Rodríguez J 《European urology》1999,35(4):318-322
OBJECTIVES: To determine conventional computed tomography (CT) signs in the diagnosis and staging of upper urinary tract tumors (UUTTs). METHODS: Retrospective study was made of the CTs of 82 patients diagnosed with UUTTs. Nine CT signs were defined and compared with the pathology of the surgical specimen. A chi2 test was used for statistical analyses. RESULTS: We reviewed the CTs of 93 UUTTs in 82 patients, of which 36% were invasive and 12% had positive lymph nodes. Renal parenchymal invasion was found in 82% of high-grade and in 18% of low-grade tumors (p = 0.001). 94% of the tumors with signs of renal parenchymal invasion were invasive (p < 0.001), as well as 88% of those appearing as renal masses (p = 0.005), with a global sensitivity of 64% and specificity of 97%. The CT sensitivity and specificity of detecting infiltration of the ureter was 67 and 77%, respectively, and no sign was statistically significant. The detection of lymph node involvement had a sensitivity of 87.5% and a specificity of 98%. CONCLUSIONS: CT offers good sensitivity (87.5%) and specificity (98%) in the detection of lymph node involvement, and 64% sensitivity and 97% specificity for the detection of renal tumor invasion. 相似文献
18.
Karina Richani Roberto Romero Yeon Mee Kim Enola Cushenberry Eleazar Soto Yu Mi Han Jimmy Espinoza Chong Jai Kim 《The journal of maternal-fetal & neonatal medicine》2006,19(8):509-515
OBJECTIVE: Tissue microarray (TMA) technology allows simultaneous examination of the expression of many molecular markers (protein, mRNA, DNA, etc.) with high-throughput. The application of this technology, to date, has been largely confined to the study of cancer. Placental pathology poses unique challenges because of the size of the organ, its complex anatomy, as well as its histological heterogeneity. The objective of this study was to assess the feasibility and efficiency of TMAs for immunohistochemistry and in situ hybridization of placental tissues. STUDY DESIGN: TMAs were constructed using an automated tissue arrayer. Standard 0.6-mm or 1-mm microarray needles were used. Villous parenchyma, basal plate, and chorioamniotic membranes were targeted in each block. Five mum-thick TMA sections underwent immunohistochemical analysis of both cytoplasmic and nuclear antigens using a panel of antibodies against a variety of cytoplasmic [cytokeratin-7, vascular endothelial growth factor (VEGF), and protein Z], membranous (endoglin), and nuclear (c-fos and c-jun) antigens. mRNA in situ hybridization for surfactant protein A (SP-A) and chromogenic in situ hybridization for the Y chromosome (DYZ1) were also performed. RESULTS: Validation of TMA immunoreactivity demonstrated comparable results with corresponding whole sections. When a two-tiered scoring system (positive/negative) was employed, there was agreement between two and three cores and whole tissue sections (kappa>0.7). When a three-tiered scoring system (negative, weak-positive, or strong-positive) was used, the data from three cores showed the highest agreement with whole tissue sections (kappa >0.7). In situ hybridization experiments for mRNA and DNA were also successful in that the signals were readily detectable. Successful transfer from the donor block to the recipient block differed according to the anatomical compartment. The transfer efficiency of villous parenchyma, basal plate, and chorioamniotic membranes were 96.9% (875/903), 76.7% (115/150), and 75.4% (224/297), respectively. CONCLUSION: TMA is a practical and effective tool for high-throughput molecular analysis of the human placenta. Duplicate and triplicate cores offer agreement with whole tissue sections for two-category distinction immunostaining. TMA also affords relevant results from in situ hybridization experiments for mRNA and DNA. The major advantages are the conservation of tissues and reagents, simultaneous comparison of molecular markers in different anatomical compartments of the placenta, and reduction of experimental error. 相似文献
19.
20.
A panel of 19 monoclonal antibodies (MAbs) against human tissue-nonspecific (liver/bone/kidney) alkaline phosphatase (TNAP) was obtained through the ISOBM TD-9 workshop. In the present study, the reactivity of these MAbs has been characterized against mouse TNAP. A mouse embryonic stem cell line, frozen sections of long bones, alkaline phosphatase extracted from mouse bone, and serum were used as the source of TNAP for individual assays. Each MAb was tested for immunoreactivity to mouse TNAP by Western blot analysis, immunohistochemistry and enzyme immunoassay. Antibodies 314 and 315 reacted strongly with mouse TNAP in Western blots, while all other antibodies were negative. By immunohistochemistry, antibodies 314, 315 and 333 produced strong positive staining using frozen sections, while antibody 334 was moderately positive. Enzyme immunoassays indicated that MAb 333 was also able to bind to serum TNAP. These antibodies represent very useful reagents to study the pathophysiological expression of TNAP in mouse tissues and in mouse serum. 相似文献