首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1572篇
  免费   67篇
  国内免费   8篇
耳鼻咽喉   3篇
儿科学   21篇
妇产科学   16篇
基础医学   216篇
口腔科学   17篇
临床医学   101篇
内科学   407篇
皮肤病学   12篇
神经病学   96篇
特种医学   42篇
外科学   400篇
综合类   4篇
预防医学   35篇
眼科学   22篇
药学   81篇
中国医学   2篇
肿瘤学   172篇
  2023年   11篇
  2022年   17篇
  2021年   30篇
  2020年   16篇
  2019年   22篇
  2018年   20篇
  2017年   22篇
  2016年   32篇
  2015年   33篇
  2014年   40篇
  2013年   45篇
  2012年   76篇
  2011年   79篇
  2010年   36篇
  2009年   35篇
  2008年   64篇
  2007年   78篇
  2006年   73篇
  2005年   84篇
  2004年   77篇
  2003年   95篇
  2002年   80篇
  2001年   56篇
  2000年   70篇
  1999年   64篇
  1998年   23篇
  1997年   37篇
  1996年   18篇
  1995年   9篇
  1994年   15篇
  1993年   13篇
  1992年   33篇
  1991年   27篇
  1990年   26篇
  1989年   25篇
  1988年   15篇
  1987年   17篇
  1986年   20篇
  1985年   34篇
  1984年   13篇
  1983年   14篇
  1982年   7篇
  1981年   4篇
  1980年   5篇
  1979年   8篇
  1978年   5篇
  1972年   4篇
  1971年   10篇
  1970年   2篇
  1968年   2篇
排序方式: 共有1647条查询结果,搜索用时 31 毫秒
81.
BACKGROUND: Although mutations in the p53 suppressor gene in thyroid carcinoma have usually been detected in anaplastic carcinoma, P53 protein expression has been detected immunohistochemically in papillary thyroid carcinoma (PTC). In the present study, we examined the immunohistochemical expression of P53 protein in PTC to investigate the relations between its expression and the clinicopathologic features. METHODS: The study was performed on 68 patients in whom thyroidectomy with lymph node dissection had been performed to treat PTC at Teikyo University Hospital. Expression of P53 protein was evaluated immunohistochemically in sections of paraffin-embedded tissue in 68 primary tumors and 196 lymph node metastases. RESULTS: Overexpression of P53 protein in the primary tumor was observed in 29 cases (43%). Statistical analysis revealed significant correlation between P53 protein expression in the primary tumor and large tumor size (unpaired t-test: p < 0.01), the presence of lymph node metastasis (unpaired t-test: p < 0.05), and the mean number of lymph node metastases (unpaired t-test: p < 0.05). Although 29 (43%) of the primary tumors overexpressed P53 protein, 143 (73%) of the metastatic lymph nodes overexpressed P53 protein irrespective of whether there was P53 overexpression by the primary tumor. CONCLUSIONS: The results of this study suggest that immunohistochemistry for P53 in the primary tumor could be useful in the clinical evaluation of patients with PTC. Moreover, P53 protein overexpression in lymph node metastasis may be useful as a treatment guide or target for lymph node recurrences.  相似文献   
82.
Detection of sentinel lymph nodes in patients with papillary thyroid cancer   总被引:7,自引:0,他引:7  
OBJECTIVES: To determine the feasibility of sentinel lymph node biopsy as a means of evaluating the cervical lymph nodes of patients with papillary thyroid cancer. METHODS: Isosulfan blue dye was injected around the tumour of 68 patients with papillary thyroid cancer; sentinel lymph node biopsy was performed in addition to subtotal thyroidectomy and central and modified lateral neck lymph node dissections. Surgical specimens were examined by routine processing to determine whether metastasis was present. RESULTS: Sentinel lymph nodes were identified in 63 (92.6%) of the 68 patients. There was concordance between the sentinel lymph node status and the final regional lymph node status in 58 (92.1%) of the 63 patients. There were five false-negative cases. Sentinel lymph node biopsy had a sensitivity of 87.5% (35/40), specificity of 100% (23/23), positive predictive value of 100% (35/35), negative predictive value of 82.1% (23/28), and accuracy of 92.1% (58/63). CONCLUSIONS: Sentinel lymph node biopsy may allow discrimination between patients with true lymph-node-negative papillary thyroid carcinoma and those with non-palpable metastatic lymph nodes. It may also be helpful in diagnosing metastases and avoiding unnecessary lymph node dissection in thyroid cancer.  相似文献   
83.
We have established a radioimmunoassay method for calcitonin gene-related peptide (CGRP) to monitor changes in plasma CGRP levels in patients with medullary thyroid carcinoma (MTC). Preoperative plasma CGRP levels (normal level less than 12.7 pg/ml) were as high as 128 pg/ml to 2,010 pg/ml in all five patients with MTC. Ten of 17 postoperative patients with MTC were positive for CGRP. A provocation test was performed in 12 patients with MTC. Plasma CGRP changes roughly paralleled serum calcitonin levels. In particular, in three patients with poorly-differentiated MTC which progressed aggressively, plasma CGRP levels were increased to 1.4 to 2.0 times levels before the test, i.e., lower than the 2.8- to 23.3-fold increase in nine patients with the well-differentiated MTC. These results suggest that CGRP may be a humoral marker of medullary carcinoma and be related to degree of malignancy.  相似文献   
84.
 Although cyclic neutropenia (CN) has been the subject of extensive studies due to its striking clinical picture, the abnormality of hematopoietic progenitor cells in patients with CN has been poorly defined. We studied the sensitivity of progenitor cells of a CN patient to colony-stimulating factors (CSF) including G-CSF, interleukin-3 (IL-3), and stem cell factor (SCF). Peripheral blood progenitor cells of the patient required a significantly higher dose of G-CSF to give rise to colonies than those of normal controls. While the presence of SCF enhanced the number of G-CSF-induced colonies regardless of the concentration of G-CSF in normal controls, this synergistic effect of SCF was limited to the high concentration of G-CSF in the patient, indicating that the abnormality in hematopoiesis in CN involved more immature progenitor cells responsive to SCF. Received: July 30, 1998 / Accepted: November 12, 1998  相似文献   
85.
The immune system of females is capable of recognizing and reacting against the male-specific minor histocompatibility antigen (mHA), HY. Thus, cytotoxic T-lymphocytes (CTLs) recognizing this antigen may be useful in eradicating leukemic cells of a male patient if they can be generated in vivo or in vitro from a human leukocyte antigen (HLA)-identical female donor. The HLA-A*0201-restricted HY antigen, FIDSYICQV, is a male-specific mHA. Using HLA-A2/HY peptide tetrameric complexes, we reveal a close association between the emergence of HY peptide-specific CD8(+) T cells in peripheral blood and molecular remission of relapsed BCR/ABL(+) chronic myelogenous leukemia in lymphoid blast crisis in a patient who underwent female-to-male transplantation. Assessment of intracellular cytokine levels identified T cells that produce interferon-gamma in response to the HY peptide during the presence of HY tetramer-positive T cells. These results indicate that transplant with allogeneic HY-specific CTLs has therapeutic potential for relapsed leukemia, and that expansion of such T cells may be involved in the development of a graft-versus-leukemia response against lymphoblastic leukemia cells.  相似文献   
86.
Purpose: Introduction of rituximab has largely improved the prognosis of patients with diffuse large B‐cell lymphoma(DLBCL). Such change in therapeutic outcome necessitates the identification of additional prognostic factors to conventional indexes that have been validated for CHOP without rituximab. Indoleamine 2,3‐dioxygenase (IDO) exerts intense immunomodulatory effects because of enzymatic activities that catalyze the breakdown of the essential amino acid L‐tryptophan. The activity of IDO can be estimated by measuring the serum concentration of L ‐kynurenine. Here, we investigated the role of L ‐kynurenine as a prognostic marker in R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) therapy. Experimental design: Data from 73 consecutive patients treated with eight cycles of R‐CHOP or R‐THP (tetrahydropyranyl adriamycin)‐COP between December 2002 and March 2007 were analyzed. L ‐kynurenine concentrations in serum samples obtained at admission were measured by high‐performance liquid chromatography. Results: The median serum L ‐kynurenine level was 1.575 μm (range 0.537–9.588). The complete response (CR) rates of patients with L ‐kynurenine <1.5 and ≥1.5 μm were 83% and 61%, respectively (P < 0.05). The three‐yr overall survival (OS) rates for patients with L ‐kynurenine <1.5 and ≥1.5 μm were 89% and 58%, respectively (P < 0.005). In addition, higher age, poor performance status, elevated serum lactate dehydrogenase, and unfavorable as well as revised International Prognosis Index were significantly worse factors for CR rate and OS. Multivariate analyses revealed only L ‐kynurenine as an independent prognostic factor for OS. Conclusions: Serum L ‐kynurenine might be a novel prognostic factor to determine the treatment outcome of DLBCL with the R‐CHOP regimen.  相似文献   
87.
88.
PURPOSE: To report an 82-year-old woman with multiple myeloma who developed an orbital T-cell lymphoma concomitantly. METHODS: The patient presented with left upper eyelid swelling. Magnetic resonance imaging demonstrated an orbital mass compressing the eyeball. The mass was excised for diagnostic purposes and orbital decompression. RESULTS: Histopathologic and immunohistochemical evaluation identified the mass as a T-cell lymphoma. The disease progressed rapidly despite chemotherapy. CONCLUSIONS: Orbital T-cell lymphoma is rare and we are unaware of previous reports of orbital T-cell lymphoma in patients with multiple myeloma.  相似文献   
89.
90.
Miki T  Ito K 《Clinical calcium》2002,12(11):1559-1564
BMD measurement is the most common practical method to evaluate the efficacy of the treatment. As the signal/noise ratio of lumber BMD is better than the other part of BMD measurement, the best site for the evaluation of therapy is lumber spine. If evaluation at lumber spine is difficult, hip BMD, followed by peripheral BMD may be selected. Special care must be taken if peripheral BMD is measured, because of low signal/noise ratio. The interval between BMD measurements is usually 6 months, and it should be longer than this period, if peripheral BMD is utilized.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号