全文获取类型
收费全文 | 435篇 |
免费 | 53篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 3篇 |
妇产科学 | 2篇 |
基础医学 | 37篇 |
口腔科学 | 4篇 |
临床医学 | 30篇 |
内科学 | 101篇 |
皮肤病学 | 1篇 |
神经病学 | 50篇 |
特种医学 | 19篇 |
外科学 | 60篇 |
综合类 | 15篇 |
预防医学 | 56篇 |
眼科学 | 5篇 |
药学 | 11篇 |
肿瘤学 | 87篇 |
出版年
2019年 | 5篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2016年 | 11篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 19篇 |
2011年 | 22篇 |
2010年 | 9篇 |
2009年 | 13篇 |
2008年 | 23篇 |
2007年 | 17篇 |
2006年 | 34篇 |
2005年 | 32篇 |
2004年 | 40篇 |
2003年 | 18篇 |
2002年 | 26篇 |
2001年 | 10篇 |
2000年 | 11篇 |
1999年 | 7篇 |
1997年 | 2篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1971年 | 2篇 |
1970年 | 7篇 |
1968年 | 3篇 |
1967年 | 6篇 |
1965年 | 2篇 |
1962年 | 4篇 |
排序方式: 共有490条查询结果,搜索用时 931 毫秒
61.
62.
63.
A major obstacle to successful autologous bone marrow transplantation in breast cancer is infiltration of the marrow by malignant cells. We layered bone marrow samples from seven breast cancer patients on a discontinuous bovine albumin gradient, then assessed hematopoietic potential (colony-forming units-culture [CFUc]) and clonogenic tumor cells (TCFUc) by standard techniques. We found that 78% of CFUc concentrated in fraction 3 of the gradient, which contained 10% of the total nucleated cell population. TCFUc were distributed across the gradient with 14% of colonies identified in this marrow fraction. We applied these techniques to two patients with metastatic breast cancer who were treated with high-dose mitomycin-C, doxorubicin, and cyclophosphamide before receiving 1.9 x 10(9) and 1.2 x 10(9) total cells, respectively, from CFUc-rich fraction 3. We observed tumor colony growth in three patients only in separated marrow fractions, suggesting that colony growth may be a function of the cell composition after fractionation or that growth factors may be separable. Ninety percent of clonogenic breast cancer cells can be separated from hematopoietic cells by discontinuous density gradient fractionation, a technique that is applicable to the large volumes necessary in bone marrow transplantation and that may be an important initial step in marrow purging for autologous transplantation. 相似文献
64.
D M Gudeman M W Brightman E M Merisko C R Merril 《Journal of neuroscience research》1989,24(2):184-191
Protein synthesis and secretion by the choroid plexus (CP) has been implicated as a major source of certain proteins in cerebrospinal fluid (CSF), such as transthyretin. The suggestion that proteins are elaborated from CP through apocrine secretion has been borne out by the presence of newly labeled proteins in apical protrusions from CP (Agnew et al.: Cell and Tissue Research 208:261-281, 1980a). When the protrusions (aposomes) separate from the cells, they continue to incorporate labeled amino acids (Gudeman et al.: Tissue and Cell 19:101-109, 1987). In the present work the formation of aposomes in live CP explants indicated that these spheroids were not the result of fixation. Aposomes were also identified within rat CSF by immunohistochemistry with monoclonal directed against aposomes as well as with anti-transthyretin serum. The protein product of aposomes was characterized by 2-dimensional SDS-PAGE and compared to the protein products of whole CP tissue. Paradoxically, transthyretin, a heavily labeled protein in the tissue, was virtually undetected in the aposome synthetic profile. However, four other proteins were expressed in relatively equivalent amounts by the aposomes. The presence of mRNA in aposomes was detected with a poly dT probe, and the presence of actin was revealed by phalloidin staining of aposomes. These studies provide a more comprehensive definition of aposomes, but the functions of their secreted proteins remains to be determined. 相似文献
65.
Immunocytochemical method to identify myelin basic protein in oligodendroglia and myelin sheaths of the human nervous system 总被引:7,自引:0,他引:7
Y Itoyama N H Sternberger M W Kies S R Cohen E P Richardson H Webster 《Annals of neurology》1980,7(2):157-166
To study the distribution of basic protein (BP) and other myelin constituents immunocytochemically in human nervous tissue, we modified the unlabeled antibody enzyme (peroxidase-antiperoxidase) method. The technique is described here. Because the availability of unfixed tissue from human central nervous system is limited, we tested the method on blocks that had been fixed in formalin and embedded in paraffin, fixed and stored in 4% formalin, or frozen at autopsy and stored. We obtained the best results with paraffin blocks. BP antiserum stained oligodendroglia and myelin sheaths in the developing human nervous system. In the adult, myelin sheaths were well stained. Also, abnormalities associated with myelin breakdown could be identified in multiple sclerosis lesions. The results suggest that this method will be useful in studying the cellular distribution of myelin components in human demyelinating diseases. 相似文献
66.
Ordinal regression model and the linear regression model were superior to the logistic regression models 总被引:1,自引:0,他引:1
Norris CM Ghali WA Saunders LD Brant R Galbraith D Faris P Knudtson ML;APPROACH Investigators 《Journal of clinical epidemiology》2006,59(5):448-456
OBJECTIVE: Ordinal scales often generate scores with skewed data distributions. The optimal method of analyzing such data is not entirely clear. The objective was to compare four statistical multivariable strategies for analyzing skewed health-related quality of life (HRQOL) outcome data. HRQOL data were collected at 1 year following catheterization using the Seattle Angina Questionnaire (SAQ), a disease-specific quality of life and symptom rating scale. STUDY DESIGN AND SETTING: In this methodological study, four regression models were constructed. The first model used linear regression. The second and third models used logistic regression with two different cutpoints and the fourth model used ordinal regression. To compare the results of these four models, odds ratios, 95% confidence intervals, and 95% confidence interval widths (i.e., ratios of upper to lower confidence interval endpoints) were assessed. RESULTS: Relative to the two logistic regression analysis, the linear regression model and the ordinal regression model produced more stable parameter estimates with smaller confidence interval widths. CONCLUSION: A combination of analysis results from both of these models (adjusted SAQ scores and odds ratios) provides the most comprehensive interpretation of the data. 相似文献
67.
Esmaeli B Golio D Kies M DeMonte F 《Ophthalmic plastic and reconstructive surgery》2006,22(5):366-370
PURPOSE: To review our experience with multidisciplinary surgical management of locally advanced adenoid cystic carcinoma of the lacrimal gland. METHODS: We present a case series of 7 patients with lacrimal gland adenoid cystic carcinoma treated at our institution between June 2001 and October 2003. Clinical records, histologic sections, and radiographic images were reviewed. RESULTS: The study included 3 men and 4 women (mean age at diagnosis, 44 years). All 7 patients underwent an orbital exenteration with bone removal. Five patients had an orbitectomy through a craniotomy approach and 2 patients had an exenteration through a fronto-orbito-zygomatic approach, all with removal of the bone of the superior and lateral wall. Six patients underwent reconstruction of the socket through the use of a vascularized flap. The surgical approach involved a neurosurgeon, an oculoplastic or head and neck surgeon, and a plastic surgeon. Six patients received postoperative radiation therapy. One patient with a recurrent tumor had already received radiation therapy, which precluded additional radiation therapy after surgical resection. The radiation field included the orbit and the skull base because all patients had evidence of perineural invasion. As of this writing, there have been no local recurrences. Five patients had development of distant metastases and died of disease, at follow-up times from 12 to 32 months after surgery. Two patients are alive without evidence of disease, both at 24 months' follow-up. CONCLUSIONS: Orbitectomy with bone removal may be indicated for achieving local and regional control in advanced cases of adenoid cystic carcinoma of the lacrimal gland. This surgery does not decrease the risk of distant metastasis. The cases in our series highlight the locally invasive and metastatic behavior of this cancer. 相似文献
68.
Autosensitization to some central nervous system antigen still remains one of the best hypotheses for the continuing pathogenesis of multiple sclerosis (MS). Enough is now known about the cause, pathogenesis, and treatment of experimental allergic encephalomyelitis (EAE) to test this hypothesis. Reports of therapeutic failure of the encephalitogen myelin basic protein (BP) in the treatment of MS have their counterparts in similar therapeutic failures in EAE. Only highly inbred strain 13 guinea pigs respond consistently to BP therapy, and this only when BP is administered in relatively high doses. Noninbred guinea pigs respond much less well to simple BP therapy, and monkeys hardly at all. In both strains of monkeys so far studied, a nonspecific adjunctive factor--an antibiotic in Macaca mulatta and a steroid in Macaca fascicularis--is also required. Accordingly, human trials of the therapeutic efficacy of BP in MS should include its administration in large concentrations together with an adjunctive agent. 相似文献
69.
70.
Gilbert J Li Y Pinto HA Jennings T Kies MS Silverman P Forastiere AA 《Head & neck》2006,28(3):197-204
BACKGROUND: Malignant tumors of the salivary glands make up approximately 5% of head and neck cancers. The Eastern Cooperative Oncology Group (ECOG) initiated a phase II evaluation of paclitaxel in patients with locally recurrent or metastatic salivary gland malignancies. METHODS: Chemo-naive patients with histologically confirmed recurrent or metastatic carcinoma of salivary gland origin (mucoepidermoid, adenocarcinoma, or adenoid cystic) were eligible. Patients were treated with paclitaxel, 200 mg/m(2) IV, every 21 days for a minimum of four cycles. RESULTS: Forty-five patients were treated. Eight partial responses were seen among the 31 patients with mucoepidermoid or adenocarcinoma histologic findings for a response rate of 26%. No responses were seen in the adenoid cystic carcinoma group. No significant difference in overall survival was found among these three histologic subgroups. CONCLUSION: Paclitaxel demonstrates moderate activity in salivary gland tumors of mucoepidermoid and adenocarcinoma histology. The poor response rate in adenoid cystic carcinoma is consistent with prior reports in this chemoresistant histologic subtype. 相似文献