全文获取类型
收费全文 | 7078篇 |
免费 | 460篇 |
国内免费 | 52篇 |
专业分类
耳鼻咽喉 | 47篇 |
儿科学 | 181篇 |
妇产科学 | 228篇 |
基础医学 | 947篇 |
口腔科学 | 78篇 |
临床医学 | 617篇 |
内科学 | 1725篇 |
皮肤病学 | 336篇 |
神经病学 | 867篇 |
特种医学 | 203篇 |
外科学 | 799篇 |
综合类 | 12篇 |
预防医学 | 362篇 |
眼科学 | 146篇 |
药学 | 433篇 |
中国医学 | 9篇 |
肿瘤学 | 600篇 |
出版年
2024年 | 11篇 |
2023年 | 70篇 |
2022年 | 103篇 |
2021年 | 256篇 |
2020年 | 154篇 |
2019年 | 187篇 |
2018年 | 185篇 |
2017年 | 171篇 |
2016年 | 202篇 |
2015年 | 231篇 |
2014年 | 278篇 |
2013年 | 356篇 |
2012年 | 522篇 |
2011年 | 541篇 |
2010年 | 271篇 |
2009年 | 294篇 |
2008年 | 422篇 |
2007年 | 406篇 |
2006年 | 373篇 |
2005年 | 380篇 |
2004年 | 328篇 |
2003年 | 323篇 |
2002年 | 268篇 |
2001年 | 140篇 |
2000年 | 124篇 |
1999年 | 130篇 |
1998年 | 76篇 |
1997年 | 39篇 |
1996年 | 46篇 |
1995年 | 51篇 |
1994年 | 40篇 |
1993年 | 30篇 |
1992年 | 72篇 |
1991年 | 57篇 |
1990年 | 52篇 |
1989年 | 58篇 |
1988年 | 37篇 |
1987年 | 50篇 |
1986年 | 46篇 |
1985年 | 36篇 |
1984年 | 21篇 |
1983年 | 17篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1980年 | 9篇 |
1979年 | 10篇 |
1975年 | 11篇 |
1969年 | 11篇 |
1968年 | 14篇 |
1966年 | 9篇 |
排序方式: 共有7590条查询结果,搜索用时 15 毫秒
21.
Ottavio Rena Esther Papalia Alberto Oliaro PierLuigi Filosso Enrico Ruffini Giuliano Maggi Caterina Casadio 《European journal of cardio-thoracic surgery》2006,30(2):217-222
OBJECTIVE: Development of distant metastases is one of the primary characteristics of malignant tumours. During the last decades, lung metastasectomy has been progressively accepted as a therapeutic option in oncology patients. The present paper aims to evaluate the long-term results and factors influencing prognosis in patients submitted to lung resection for metastases from extrapulmonary epithelial tumours. METHODS: We retrospectively analysed data of 202 patients undergoing 207 procedures of lung metastasectomy between January 1980 and December 2003. Factors that may influence long-term prognosis such as completeness of resection, histology of the tumour, disease-free interval, number of resected lesions, involvement of hilar or mediastinal lymph nodes, systemic treatments were investigated. RESULTS: Complete resection was carried out in 169 patients (83.7%). The more frequent lung resection was sublobar in 67.6% of cases, but rarely in selected patients bilobectomy or pneumonectomy has been carried out too. Perioperative morbidity and mortality were 7.7% and 0.9%. Mean disease-free interval was 49+/-48 months. Mean follow-up was 33+/-31 months, 5-year and 10-year survival rates for completely resected patients were 43% and 17%, respectively. By univariate and multivariate analyses, completeness of resection, disease-free interval of 36 months or more, and single resected metastasis were found to be significant prognostic factors. CONCLUSIONS: Resection of epithelial lung metastases allows an acceptable prognostic result in appropriately selected patients with very low perioperative morbidity and mortality. Factors such as high disease-free interval, single metastasis and completeness of resection are demonstrated and confirmed to be significantly associated with long-term survival. 相似文献
22.
R. Perniola M. L. Faneschi E. Manso M. Pizzolante A. Rizzo A. Sticchi Damiani R. Longo 《European journal of clinical microbiology & infectious diseases》2006,25(3):193-196
Reported here are the features of a Rhodotorula mucilaginosa outbreak that occurred in a neonatal intensive care unit. Over a period of 19 days, clinical and laboratory signs of sepsis appeared in four premature infants carrying indwelling vascular catheters. After bloodstream infection with R. mucilaginosa was ascertained, the patients underwent amphotericin B therapy and recovered completely. In a retrospective case-control study, the variables displaying a statistical difference between case and control-group neonates were birth weight, gestational age, duration of parenteral nutrition, duration of antibiotic therapy and prophylactic administration of fluconazole. To our knowledge, this is the first reported outbreak caused by yeasts of the Rhodotorula genus. 相似文献
23.
A. Tosto E. Dattolo S. Serni M. Rizzo A. Costantini 《Current therapeutic research》1995,56(12):1270-1275
A double-blind, randomized, comparative study of mepartricin (SPA-S-160) and placebo was performed on 36 patients who complained of obstructive symptomatology caused by prostatic hypertrophy. Treatment was continued for 60 days at a dose of 150,000 IU/d (three capsules/d) of active substance. All patients underwent full urodynamic investigation consisting of pressure-flow studies before and after treatment. The final results of our study showed that 50% of the patients treated with mepartricin had an improvement in micturitional performance. 相似文献
24.
G Lucignani G Paganelli G Modorati S Pieralli G Rizzo P Magnani F Colombo F Zito C Landoni G Scotti 《Journal of computer assisted tomography》1992,16(1):77-83
To evaluate the usefulness of structural and biochemical imaging techniques for the diagnosis of uveal melanoma, 12 patients with choroidal melanoma were examined. Magnetic resonance imaging was used in 11 of 12 patients, as one had a metal prosthesis. All the subjects underwent single photon planar scintigraphy (SPPS) and single photon emission computed tomography (SPECT) using the 99mTc-labeled F(ab')2 of the anti-melanoma monoclonal antibody 225.28S ([99mTc]MoAb) and positron emission tomography (PET) using [18F]fluorodeoxyglucose ([18F]FDG). Magnetic resonance identified 6 of 11 melanotic lesions (definite melanomas) and 4 of 11 hypomelanotic lesions (probable melanomas), whereas in one case it was inconclusive. [99mTc]MoAb uptake was observed in 5 of 12 lesions using SPPS and 8 of 12 lesions using SPECT. [18F]FDG uptake was observed in 3 of 12 lesions by PET. These results demonstrate that both MR and radioimmunoscintigraphy are sensitive techniques for the diagnosis of choroidal melanomas and suggest that the detection of melanomas by MR, SPPS, and SPECT is largely dependent upon their size. The validity of these conclusions was verified in four subjects in whom the diagnosis was based on MR and/or SPECT findings only and confirmed by histology. The finding that only some of the uveal melanomas of larger size are visualized based on [18F]FDG uptake suggests that melanomas can have either high or low glucose consumption. 相似文献
25.
Angeto Avogaro MD Mauro Cibin MD Tiziano Croatto MD Alberto Rizzo MD Luigi Gallimberti MD Antonio Tiengo MD 《Alcoholism, clinical and experimental research》1986,10(3):300-304
The effects of chronic alcohol consumption on plasma branched chain amino acids and alanine concentrations were evaluated, and basal blood concentrations of these amino acids were determined after chronic ethanol intake and following a withdrawal period in 30 admitted alcoholics. After ethanol intake, alcoholics showed increased branched chain amino acid concentrations; the blood alanine concentrations were depressed after the withdrawal period. To evaluate the effect of ethanol on diurnal variations of these amino acids in the blood, a group of these patients underwent two isocaloric diets with and without wine. The diet with alcohol induced a sustained increase of branched chain amino acids persisting even after the postprandial phase with a decrease of alanine as compared to the diet without. 相似文献
26.
In a recent paper, we showed that the number of endoneurial microvessels per square millimeter and the average luminal area and size distribution of these microvessels are not significantly different in sural nerves of patients with diabetes mellitus as compared to control subjects. Mural area, especially the component due to basement membrane reduplication and cellular debris, was unequivocally increased in diabetes mellitus. Because these latter changes are associated with a decrease in periendothelial cell area, we hypothesized that cellular degeneration, especially of pericytes, may account for basement membrane reduplication and increased frequency of cellular debris. In the present study, we showed that endoneurial microvessels undergo a statistically significant increase in basement membrane area, mural area, and frequency of cellular debris in diabetics without polyneuropathy and an even greater increase in diabetics with polyneuropathy. We also found that duration of diabetes mellitus was significantly associated with area occupied by reduplicated basement membrane and cellular debris, but not with mural and periendothelial area. None of the examined measurements was associated with age. Since the microvessel abnormalities we describe are already present before the development of polyneuropathy and increase with severity of polyneuropathy, it is likely that they reflect functional derangements of pericytes and microvessel function which precede and might be implicated in fiber degeneration. 相似文献
27.
C. Brandimarte C. Santini M. Venditti P. Baiocchi P. Serra P. Gallo G. d'Amati L. Rizzo F. Speziale P. Fiorani 《European journal of epidemiology》1989,5(4):521-525
To investigate the clinical significance of intraoperative cultures in elective abdominal aortic aneurysmectomy, we cultured the aneuryrymml wall and contents in 90 patients undergoing vascular graft surgery. Prosthetic graft infection was documented in 1 out of 62 patients with negative cultures and in none of 28 patients with positive cultures (x2 = 0.4, p > 0.1). Bacterial growth was seen in neither of 2 inflammatory aneurysms, 3 of 14 atherosclerotic aneurysms and 2 of 5 aneurysms without specific features. A retrospective analysis of patients' charts aimed at finding possible risk factors failed to identify any correlation between results of cultures and length of hospitalization before surgery, time interval between angiography and surgery, route of angiography procedure or minutes of surgery before sample collection. We conclude that positive cultures may not imply clinical infection at the time of surgery and that prolonged post-operative organism-specific antibiotic therapy does not appear necessary to prevent graft contamination in patients undergoing elective abdominal aortic aneurysmectomy. 相似文献
28.
It has been suggested for many years that the regulation of the immune system for the maintenance of peripheral tolerance may involve regulatory/suppressor T cells. In the past few years, several investigators have demonstrated that these cells can be generated in vitro. It has also been shown that they can inhibit the progression of various autoimmune disease models when infused into susceptible mice. We have generated two murine T cell lines in the presence of KLH-specific T cell clones from BALB/c or DBA2 mice. The lines are characterized by a low proliferative response to mitogens, the capacity to secrete high amounts of IL-10 and TGF-beta, and small amounts of IFN-gamma. Interestingly, these cells are unable to produce IL-2, IL-4 or IL-5. The study of the surface phenotype of both lines revealed CD4+, CD25high, CD44low and CTLA-4- cells. When injected intravenously in (CBy.D2) F1 mice, these cells were able to inhibit 50-100% of the TNP-specific antibody production, when the hapten was coupled to KLH. In the present study we offer another evidence for the existence of regulatory T cells in the T lymphocyte repertoire, suggesting that they can also regulate immune responses to foreign antigens. Furthermore, we demonstrate an alternative pathway to generate these cells different from approaches used thus far. 相似文献
29.
Antonino Carbone Annunziata Gloghini Ivana Zanette Barbara Canal Aurora Rizzo Rachele Volpe 《Virchows Archiv : an international journal of pathology》1993,422(1):39-45
Summary The presence of Epstein-Barr virus (EBV) genome in Hodgkin's and Reed-Sternberg (HRS) cells, as detected using in situ hybridization (ISH) with biotinylatedBamHI V probes, along with the expression of EBV-encoded latent membrane protein (LMP) and vimentin was examined in paraffin-embedded sections of 39 immunomorphologically characterized cases of Hodgkin's disease (HD). ISH demonstrated EBV in HRS cells in 15 of 39 cases, whereas LMP expression was detected in 11 of 39 cases, only in the presence of EBV genome detection. With the exception of 1 case, in which HRS cells expressed B-cell-associated antigens, the LMP-positive cases included specimens in which HRS cells were of non-B, non-T phenotype. LMP expression showed a stronger association with lymphocyte depletion (LD) (3/3) and mixed cellularity (MC) (6/11) than with lymphocyte predominance (0/5) or nodular sclerosis (2/20) subtypes. Vimentin expression on HRS cells was found in all the LMP-expressing cases and only in a fraction (13/28) of LMP-negative cases. This study supports the view that HD represents a heterogeneous group of diseases also in terms of EBV association, LMP expression being strongly related to the aggressive LD and MC histological subtypes. In light of the supposed interactions between vimentin and LMP, their coexpression on HRS cells, as detected in this study, provides further evidence for a significant role of EBV in the development of a proportion of HD cases. 相似文献
30.
Stefano M Santini Tiziana Di Pucchio Caterina Lapenta Stefania Parlato Mariantonia Logozzi Filippo Belardelli 《Journal of interferon & cytokine research》2002,22(11):1071-1080
Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs) and thus play a pivotal role in induction of the immune response. Recent studies in both human and mouse models have shown that type I IFN, cytokines originally characterized for their antiviral activity and exerting multiple biologic effects, efficiently promote the differentiation and activation of DCs. These observations, together with the findings that DCs can express biologically relevant levels of type I interferon (IFN) and, in particular, that high amounts of these cytokines are released by specialized DC precursors (i.e., plasmacytoid DCs) in response to viral infections, strongly suggest the existence of a natural alliance between type I IFN and DCs, which is instrumental in ensuring an efficient immune response to both infectious agents and tumors. Further recent knowledge on the interactions between type I IFN and DCs emphasizes the importance of these cytokines in linking innate and adaptive immunity and may lead to new perspectives in their use as vaccine adjuvants as well as in strategies for the development of DC-based vaccines. 相似文献