全文获取类型
收费全文 | 1215篇 |
免费 | 48篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 28篇 |
妇产科学 | 31篇 |
基础医学 | 112篇 |
口腔科学 | 86篇 |
临床医学 | 143篇 |
内科学 | 302篇 |
皮肤病学 | 32篇 |
神经病学 | 74篇 |
特种医学 | 70篇 |
外科学 | 117篇 |
综合类 | 11篇 |
预防医学 | 72篇 |
眼科学 | 10篇 |
药学 | 71篇 |
中国医学 | 1篇 |
肿瘤学 | 100篇 |
出版年
2022年 | 17篇 |
2021年 | 29篇 |
2020年 | 12篇 |
2019年 | 15篇 |
2018年 | 23篇 |
2017年 | 15篇 |
2016年 | 21篇 |
2015年 | 19篇 |
2014年 | 39篇 |
2013年 | 34篇 |
2012年 | 57篇 |
2011年 | 67篇 |
2010年 | 49篇 |
2009年 | 43篇 |
2008年 | 47篇 |
2007年 | 74篇 |
2006年 | 63篇 |
2005年 | 60篇 |
2004年 | 51篇 |
2003年 | 42篇 |
2002年 | 34篇 |
2001年 | 35篇 |
2000年 | 23篇 |
1999年 | 27篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 14篇 |
1995年 | 14篇 |
1992年 | 10篇 |
1991年 | 13篇 |
1990年 | 18篇 |
1989年 | 18篇 |
1988年 | 12篇 |
1987年 | 17篇 |
1986年 | 13篇 |
1985年 | 25篇 |
1984年 | 22篇 |
1983年 | 13篇 |
1981年 | 12篇 |
1980年 | 7篇 |
1979年 | 17篇 |
1978年 | 5篇 |
1977年 | 14篇 |
1975年 | 9篇 |
1974年 | 12篇 |
1973年 | 10篇 |
1972年 | 13篇 |
1971年 | 8篇 |
1969年 | 6篇 |
1960年 | 6篇 |
排序方式: 共有1266条查询结果,搜索用时 31 毫秒
991.
D'Incà R Bertomoro P Mazzocco K Vettorato MG Rumiati R Sturniolo GC 《Alimentary pharmacology & therapeutics》2008,27(2):166-172
Background Inflammatory bowel diseases are chronic conditions requiring medication throughout life to treat the disease and control the risk of relapse and colorectal cancer. Adherence to prescribed drugs is therefore crucial to their management.
Aim To identify determinants and potential risk factors of non-adherence in inflammatory bowel disease patients.
Methods An anonymous 24-item questionnaire (available online as Supplementary material) was administered to 485 out-patients attending a tertiary referral centre.
Results Sixty-one per cent of the patients reportedly adhered to their treatment. No differences emerged between inflammatory bowel disease and socio-demographic characteristics other than age, non-adherence being significantly associated with cases under 40 years (43% vs. 34%, P = 0.041). The most common reasons for non-adherence vs. adherence were forgetfulness (61% vs. 44%, P = 0.000), disease remission (25% vs. 10%, P = 0.000), recent diagnosis (24% vs. 15%, P = 0.000) and full-time employment (55% vs. 26%, P = 0.000). Oral therapy was associated with a significantly better adherence than rectal therapy (60% vs. 32%, P = 0.001). Communication affects patient adherence: a significant interaction was found for adherence and patients <40 years who had a good relationship with their doctors.
Conclusions Risk factors for non-adherence are younger age, busy working life, recent diagnosis and disease remission. Good communication with the doctor might improve adherence. 相似文献
Aim To identify determinants and potential risk factors of non-adherence in inflammatory bowel disease patients.
Methods An anonymous 24-item questionnaire (available online as Supplementary material) was administered to 485 out-patients attending a tertiary referral centre.
Results Sixty-one per cent of the patients reportedly adhered to their treatment. No differences emerged between inflammatory bowel disease and socio-demographic characteristics other than age, non-adherence being significantly associated with cases under 40 years (43% vs. 34%, P = 0.041). The most common reasons for non-adherence vs. adherence were forgetfulness (61% vs. 44%, P = 0.000), disease remission (25% vs. 10%, P = 0.000), recent diagnosis (24% vs. 15%, P = 0.000) and full-time employment (55% vs. 26%, P = 0.000). Oral therapy was associated with a significantly better adherence than rectal therapy (60% vs. 32%, P = 0.001). Communication affects patient adherence: a significant interaction was found for adherence and patients <40 years who had a good relationship with their doctors.
Conclusions Risk factors for non-adherence are younger age, busy working life, recent diagnosis and disease remission. Good communication with the doctor might improve adherence. 相似文献
992.
Renato Augusto Moreira de Sá Valeria Pereira de Moraes Marianne Cecília da Costa Soares Heron Werner Gerson Ribeiro Jorge Lopes Edward Araujo Júnior 《Journal d'obstetrique et gynecologie du Canada》2018,40(1):75-77
Background
Complete uterine rupture is a rare and severe intrapartum complication with high rates of maternal and fetal mortality. Asymptomatic uterine rupture is a very rare condition with one unique previous case described in the literature. Three-dimensional virtual models allow an immersive virtual reality of maternal-fetal structures with better understanding by the parents and the medical team.Case
We demonstrate a case of asymptomatic rupture uterine with a large amniocele and protruded legs and umbilical cord at 28 weeks of gestation by using a 3-D virtual model from ultrasound scan data.Conclusion
3-D virtual models may be applied to the assessment of obstetric complications, thereby allowing a novel 3-D spatial view of maternal-fetal structures. 相似文献993.
Moreira MA Longatto Filho A Castelo A de Barros MR Silva AP Thomann P Mattosinho de Castro Ferraz Mda G Dores GB 《Diagnostic cytopathology》2008,36(4):270-274
Gynecological cytology has some inaccurate morphological categorization and poor interobserver reproducibility especially for glandular lesions. Liquid-based cytology (LBC) preparations are presumed to reduce artifacts that interfere in diagnosis performance, but its value to correctly identify glandular alterations has not been sufficiently reported. The objective of this study was to compare the diagnostic performance and interobserver agreement of LBC and conventional Pap smear to identify histologically confirmed glandular lesions according to five cytologists. Sensitivity ranged from 55.8 to 73.1% and 32.7 to 48.1% for Pap smear and LBC, respectively. Specificity ranged from 66.1 to 87.1% and 69.4 to 94.4%, respectively. In general, agreement between pairs of cytologists was poor with kappa-values around 0.45. In conclusion, relying entirely on cervical cytology to rule out glandular lesions may be risky. The use of HPV DNA test alone or combined to screening glandular lesions may contribute to minimize the limitations of both conventional and LBC preparations to diagnose glandular abnormalities. 相似文献
994.
Recurrence and survival rates among early breast cancer cases with triple negative immunophenotype 总被引:2,自引:0,他引:2
BACKGROUND: Axillary lymph node status, hormonal receptors (HR) and HER2 expression are significant prognostic factors for early breast cancer. Triple negative immunophenotype (HER2 and HR negative) is associated with a high frequency of recurrence and lower overall survival. The objective was assess clinical behavior, recurrence and survival of patients with triple negative early breast cancer and patients with other immunophenotypes. MATERIAL AND METHODS: We carried out a retrospective study among women with stages I-IIB over 18 years with determination of HR and HER2 expression by immunohistochemical assay. We identified 5 groups: triple negative, triple positive, HER2 negative & HR positive, HER2 positive & HR negative, HER2 negative & 1 HR positive. We recorded age, date of diagnosis, clinical stage, tumor size, axillary lymph node status, ER, PR, HER2, p53, angiogenesis, Ki67, type of surgery, adjuvant treatment, time to recurrence, number and recurrence site and overall survival. RESULTS: 17 patients (15.4%) had triple negative phenotype, 14 (12.7%) triple positive, 52 (47.3%) were localized in group 3, 11 (10%) in 4 and 16 (14.5%) in group 5. Triple negative phenotype was associated with increased cellular proliferation (p < 0.000); being young (median 43 years), large tumor size (median size 2.5 cm) lower proportion of patients in stage I and high frequency of p53 positive (78.5%). We observed a high frequency of recurrence and death among the triple negative group and among the HER2 positive and HR negative cases. CONCLUSIONS: Triple negative breast cancer is more common among young women and is associated with a high frequency of recurrence and mortality. Clinical behavior among triple negative breast cancer cases is aggressive and displays a similar clinical profile that observed among HER2 positive and HR negative patients. 相似文献
995.
Wald DN Vermaat HM Zang S Lavik A Kang Z Peleg G Gerson SL Bunting KD Agarwal ML Roth BL Tse W 《Cancer research》2008,68(11):4369-4376
As the pathophysiology of acute myelogenous leukemia (AML) involves a block of myeloid maturation, a desirable therapeutic strategy is to induce leukemic cell maturation to increase the efficacy and to avoid the side effects of traditional chemotherapeutics. Through a compound library screen, 6-benzylthioinosine (6BT) was identified as a promising differentiation-inducing agent. 6BT induces monocytic differentiation of myeloid leukemia cell lines such as HL-60 and OCI-AML3, as well as primary patient samples as evidenced by morphology, immunophenotyping, and nitroblue tetrazolium reduction. Not only can 6BT induce differentiation but a subset of AML cell lines such as MV4-11 and HNT34 instead undergo 6BT-mediated cell death. Despite inducing cell death in some leukemic cells, 6BT exhibits extremely low toxicity on several nonmalignant cells such as fibroblasts, normal bone marrow, and endothelial cells. This toxicity profile may relate to the function of 6BT as an inhibitor of the nucleoside transporter, ent1, which is thought to prevent it from entering many cell types. In contrast, 6BT likely enters at least some leukemic cell lines as shown by its requirement for phosphorylation for its differentiation activity. 6BT is also able to synergize with currently used myeloid differentiation agents such as ATRA and decitabine. Early studies indicate that the mechanism of action of this compound may involve ATP depletion that leads to growth inhibition and subsequent differentiation. Besides in vitro activity, 6BT also shows the ability to impair HL-60 and MV4-11 tumor growth in nude mice. 6BT is a promising new monocytic differentiation agent with apparent leukemic cell-specific activity. 相似文献
996.
Z Tang R Du S Jiang C Wu D S Barkauskas J Richey J Molter M Lam C Flask S Gerson A Dowlati L Liu Z Lee B Halmos Y Wang J A Kern P C Ma 《British journal of cancer》2008,99(6):911-922
Despite clinical approval of erlotinib, most advanced lung cancer patients are primary non-responders. Initial responders invariably develop secondary resistance, which can be accounted for by T790M-EGFR mutation in half of the relapses. We show that MET is highly expressed in lung cancer, often concomitantly with epidermal growth factor receptor (EGFR), including H1975 cell line. The erlotinib-resistant lung cancer cell line H1975, which expresses L858R/T790M-EGFR in-cis, was used to test for the effect of MET inhibition using the small molecule inhibitor SU11274. H1975 cells express wild-type MET, without genomic amplification (CNV=1.1). At 2 μM, SU11274 had significant in vitro pro-apoptotic effect in H1975 cells, 3.9-fold (P=0.0015) higher than erlotinib, but had no effect on the MET and EGFR-negative H520 cells. In vivo, SU11274 also induced significant tumour cytoreduction in H1975 murine xenografts in our bioluminescence molecular imaging assay. Using small-animal microPET/MRI, SU11274 treatment was found to induce an early tumour metabolic response in H1975 tumour xenografts. MET and EGFR pathways were found to exhibit collaborative signalling with receptor cross-activation, which had different patterns between wild type (A549) and L858R/T790M-EGFR (H1975). SU11274 plus erlotinib/CL-387,785 potentiated MET inhibition of downstream cell proliferative survival signalling. Knockdown studies in H1975 cells using siRNA against MET alone, EGFR alone, or both, confirmed the enhanced downstream inhibition with dual MET–EGFR signal path inhibition. Finally, in our time-lapse video-microscopy and in vivo multimodal molecular imaging studies, dual SU11274-erlotinib concurrent treatment effectively inhibited H1975 cells with enhanced abrogation of cytoskeletal functions and complete regression of the xenograft growth. Together, our results suggest that MET-based targeted inhibition using small-molecule MET inhibitor can be a potential treatment strategy for T790M-EGFR-mediated erlotinib-resistant non-small-cell lung cancer. Furthermore, optimised inhibition may be further achieved with MET inhibition in combination with erlotinib or an irreversible EGFR-TKI. 相似文献
997.
998.
Kenichi Meguro Mitsue Meguro Paulo Caramelli Junichi Ishizaki Hideo Ambo Rosa Y. S. Chubaci Hiroshi Ishii Satoshi Yamaguchi Masumi Shimada Gerson S. Hamada Ricardo Nitrini Atsushi Yamadori 《Psychogeriatrics》2001,1(4):295-302
Background: Dementia, depressive state, and physical inactivity, are some of the main topics of geriatric medicine. We previously showed the prevalence of dementia in Tajiri, Miyagi Prefecture, Japan. To investigate the environmental effects, first-generation immigrants are one of the best samples. Brazil is the country with the largest number of Japanese immigrants.
Objective: To evaluate the effects of environment on dementia, depressive state, and physical activity, the Tajiri subjects and the elderly Japanese emigrants from Miyagi Prefecture to Brazil were compared.
Methods: The total elderly population in Tajiri and that the elderly members of the Miyagi Association in the São Paulo metropolitan area in Brazil were compared. All data were gathered using a standardized interview covering physical status, cognitive function (Mini-Mental State Examination, MMSE), and depressive state (Self-reported Depressive Scale, SDS). Dementia and depression were diagnosed based on the DSM-IV.
Results: Seventy-six percent of the immigrants perceived their health as being excellent or relatively good, whereas only 56% of Tajiri subjects did so. The percentage of subjects with a history of diabetes mellitus, a lifestyle related disease, was 8.4% in Tajiri and 24.2% in Brazil. In spite of similar prevalences of dementia with slightly different MMSE distributions, the two groups had a different SDS distribution; the immigrants showed lower depressive scores.
Conclusion: In spite of environmental changes influencing physical activity and diabetes, cognitive function was not apparently affected. Although the immigrants lives were marked with hardship, their depressive scores were unexpectedly lower than Japanese, probably due to their stronger mental activity. 相似文献
Objective: To evaluate the effects of environment on dementia, depressive state, and physical activity, the Tajiri subjects and the elderly Japanese emigrants from Miyagi Prefecture to Brazil were compared.
Methods: The total elderly population in Tajiri and that the elderly members of the Miyagi Association in the São Paulo metropolitan area in Brazil were compared. All data were gathered using a standardized interview covering physical status, cognitive function (Mini-Mental State Examination, MMSE), and depressive state (Self-reported Depressive Scale, SDS). Dementia and depression were diagnosed based on the DSM-IV.
Results: Seventy-six percent of the immigrants perceived their health as being excellent or relatively good, whereas only 56% of Tajiri subjects did so. The percentage of subjects with a history of diabetes mellitus, a lifestyle related disease, was 8.4% in Tajiri and 24.2% in Brazil. In spite of similar prevalences of dementia with slightly different MMSE distributions, the two groups had a different SDS distribution; the immigrants showed lower depressive scores.
Conclusion: In spite of environmental changes influencing physical activity and diabetes, cognitive function was not apparently affected. Although the immigrants lives were marked with hardship, their depressive scores were unexpectedly lower than Japanese, probably due to their stronger mental activity. 相似文献
999.
1000.
Eduardo K. Moioli Paul A. Clark Mo Chen James E. Dennis Helaman P. Erickson Stanton L. Gerson Jeremy J. Mao 《PLoS Clinical Trials》2008,3(12)
Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs) and mesenchymal stem/progenitor cells (MSCs) were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP) scaffolds, followed by infusion of gel-suspended CD34+ hematopoietic cells. Co-transplantation of CD34+ HSCs and CD34− MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromized mice yielded vascularized tissue. The average vascular number of co-transplanted CD34+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34+ cells. Based on additional in vitro results of endothelial differentiation of CD34+ cells by vascular endothelial growth factor (VEGF), we adsorbed VEGF with co-transplanted CD34+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone, adipose, muscle and dermal grafts, and may have implications in the regeneration of internal organs. 相似文献