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   1110篇
  免费   56篇
  国内免费   5篇
耳鼻咽喉   10篇
儿科学   13篇
妇产科学   10篇
基础医学   84篇
口腔科学   26篇
临床医学   70篇
内科学   346篇
皮肤病学   24篇
神经病学   49篇
特种医学   17篇
外科学   163篇
预防医学   24篇
眼科学   54篇
药学   68篇
肿瘤学   213篇
  2023年   14篇
  2022年   12篇
  2021年   27篇
  2020年   13篇
  2019年   19篇
  2018年   44篇
  2017年   27篇
  2016年   26篇
  2015年   28篇
  2014年   38篇
  2013年   47篇
  2012年   95篇
  2011年   101篇
  2010年   53篇
  2009年   57篇
  2008年   70篇
  2007年   90篇
  2006年   83篇
  2005年   83篇
  2004年   65篇
  2003年   44篇
  2002年   32篇
  2001年   13篇
  2000年   8篇
  1999年   7篇
  1998年   9篇
  1997年   5篇
  1996年   8篇
  1995年   3篇
  1994年   4篇
  1991年   4篇
  1990年   7篇
  1988年   6篇
  1987年   4篇
  1986年   4篇
  1985年   3篇
  1984年   2篇
  1983年   4篇
  1982年   1篇
  1979年   2篇
  1978年   3篇
  1977年   3篇
  1976年   1篇
  1974年   1篇
  1968年   1篇
排序方式: 共有1171条查询结果,搜索用时 31 毫秒
1.
Purpose/aim: To focus on current aspects of primary thyroid lymphoma (PTL), which is a rare clinical entity usually manifested by a rapidly growing mass in the neck that can cause pressure symptoms.

Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.

Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.

Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level.  相似文献   

2.
SUMMARY: Poor tolerance and the potential long-term toxicity have limited the widespread use of corticosteroids and cytotoxic drugs in the treatment of idiopathic membranous nephropathy (IMN). Cyclosporin A (CyA) has been proven to be a less toxic alternative, but its efficacy needs further confirmation. Cyclosporin A (2–3mg/kg per day) in combination with low-dose methylprednisolone (4mg/day) was given to 28 nephrotic patients with IMN who had failed to respond, or tolerate, or to complete treatments with steroids and/or cytotoxic drugs. the mean duration of treatment was 11 ± 7 months. Seven patients (25%) showed a complete remission of proteinuria, 17 (60%) a partial one, and four (15%) did not respond at all. the average time to achieve optimal remission was 4.2 ± 1.4 weeks following the initiation of therapy. In those who responded completely or partially, plasma creatinine (Per) did not change significantly from pre CyA levels during follow up (1.0 ± 0.3 vs 1.2 ± 0.3mg/dL, P =NS). the remaining four patients who had renal insufficiency already before CyA (mean Per: 2.1 ± 0.8mg/dL), showed a rapid deterioration of renal function after the initiation of CyA (mean Per: 3.1 ± 1.5 mg/dL, P <0.01), and as a consequence, the drug was discontinued. A mul-tivariate analysis on the clinical and histological features demonstrated that the degree of renal function impairment ( P <0.02), the percentage of obsolete glomeruli ( P <0.01), and the severity of interstitial fibrosis ( P <0.005) independently predicted the response to therapy. Low dose CyA is an effective and safe alternative treatment for patients with IMN and normal renal function. However, the drug should be given with caution to patients with established renal insufficiency.  相似文献   
3.
A 70-year-old woman had corneal ulcer and melting after complicated cataract surgery with polymethylmethacrylate lens implant insertion. A conjunctival flap was initially used to cover the defect with a plan to perform keratoplasty later. Fifteen months postoperatively, she presented with total absence of central corneal tissue and iris and exposure of the implant. The eye was not inflamed, painful, or hard on palpation and visual acuity was counting fingers at 3 m. The preservation of globe integrity despite exposure of the polymethylmethacrylate implant implies a stable adhesion between polymethylmethacrylate and residual corneal tissue and may prove useful in keratoprosthesis design.  相似文献   
4.
5.
Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study.  相似文献   
6.
This study was sought to evaluate the relationship between Her-2 protein expression, cellular localization, gene amplification, and other clinicopathologic parameters in colorectal carcinomas. Her-2 protein expression and gene amplification were assessed in paraffin sections from 106 primary colorectal adenocarcinoma cases using immunohistochemistry and fluorescence in situ hybridization. Both membranous and cytoplasmic immunostaining was evaluated. The results were correlated with each other and with tumor grade, stage, and overall survival. Membranous and cytoplasmic protein expression was identified in 6 (5.6%) and 13 (12.26%) cases, respectively. Gene amplification was detected in 4 (3.7%) cases. There was a high concordance between membranous protein expression and gene amplification (kappa=0.791). No apparent association with any of the clinicopathologic parameters was identified. Membranous Her-2 protein expression and gene amplification are encountered in a small subset of colorectal carcinomas and are highly concordant events. Cytoplasmic protein expression might be either artifactual or it might represent a cross-reacting protein or a precursor form of the mature protein.  相似文献   
7.
PURPOSE: To evaluate the efficacy and toxicity of gemcitabine (GEM) combined with capecitabine (CAP) in untreated patients with inoperable or metastatic pancreatic cancer. PATIENTS AND METHODS: Fifty-three patients with pancreatic cancer (85% stage IV) were enrolled. Patients were treated with GEM 1000 mg/m2 on days 1 and 8 and CAP 1300 mg/m2 per day PO (per os), divided into two equal doses on days 1-14, in 21-day cycles. RESULTS: In an-intention-to-treat analysis, 10 (18.9%) objective partial responses were achieved (95% confidence interval 8.33% to 29.4%). Twenty-two (42%) patients had stable disease and 15 (28%) had progressive disease. The median response time was 3 months (range 1.5-7.0) and the median time to tumor progression was 6.5 months (range 3.5-15.5). Median overall survival time was 8 months (range 1.0-15.5) and 1-year survival was 34.8%. Pain improvement during treatment was observed in 23 of 43 (53%) patients, and eight of 18 (44%) patients who had been receiving opioids discontinued their use. Weight gain was observed in 12 of 33 (36%) patients. Grade 3 anemia occurred in five (9%) patients and grade 3-4 thrombocytopenia occurred in three (6%). Grade 3-4 neutropenia occurred in 13 (25%) and five (9%) patients, respectively, and two (4%) developed febrile neutropenia. Non-hematological toxicity was mild. CONCLUSION: In patients with pancreatic cancer, the combination of GEM with CAP is an active and well tolerated regimen that merits further evaluation in prospective randomized studies.  相似文献   
8.
Abstract The case of a 7-year-old girl with a 2 year history of easy bruising associated with thrombocytopenia is reported. On admission she presented with ecchymoses, abdominal distention and splenomegaly. Hemostasis investigation revealed a consumption coagulopathy. Several radiological studies failed to confirm the diagnosis of diffuse splenic and visceral hemangiomatosis, which was eventually estasblished by an explorative laparotomy. Platelet count and the other coagulation abnormalities progressively returned to normal after splenectomy, although the remaining hemangiomas were extensive.  相似文献   
9.
BACKGROUND: To investigate the incidence of direct hematogenous spread of cancer cells in patients with early-stage breast cancer by studying the presence of occult tumor cytokeratin-19 (CK-19) mRNA(+) cells in the peripheral blood in relation to the status of sentinel (SLNs) and (ALNs) axillary lymph nodes. PATIENTS AND METHODS: SLNs and ALNs from 111 patients with operable stage I-II breast adenocarcinoma were evaluated for the presence of tumor cells by hematoxylin-eosin (H&E) staining and, if negative, by immunohistochemistry (IHC) using an anti-CK-19 antibody. Peripheral blood was also analyzed for the presence of CK-19 mRNA(+) cells by nested RT-PCR, before the initiation of adjuvant treatment and in CK-19 mRNA(+) patients following the completion of adjuvant chemotherapy and hormonal treatment. RESULTS: After both H&E staining and IHC analysis, 29 (26%) patients were ALN negative (N0). In 78 (70%) patients H&E staining and in four (3.6%) IHC analysis revealed tumors cells, and these patients were considered as ALN positive (N+). Peripheral blood CK-19 mRNA(+) cells were detected in nine (31%) out of 29 N0 and in 31 (38%) out of 82 N + patients (P=0.5) before any adjuvant treatment. Adjuvant chemotherapy and hormone treatment resulted in the disappearance of the CK-19 mRNA(+) cells in all N0 patients and in 15 out of 31 N + patients. After a median follow-up of 40 months, all the N0 CK-19 mRNA(+) patients were relapse-free whereas four (13%) N + CK-19 mRNA(+) patients had relapsed. CONCLUSIONS: Direct hematogenous dissemination of occult tumor cells may occur in a substantial proportion of patients with early-stage breast cancer. The prognostic implication of the detection of these cells requires long follow-up periods and further studies.  相似文献   
10.
PURPOSE: Osteonecrosis of the jaw (ONJ) has been associated recently with the use of pamidronate and zoledronic acid. We studied the incidence, characteristics, and risk factors for the development of ONJ among patients treated with bisphosphonates for bone metastases. PATIENTS AND METHODS: ONJ was assessed prospectively since July 2003. The first bisphosphonate treatment among patients with ONJ was administered in 1997. Two hundred fifty-two patients who received bisphosphonates since January 1997 were included in this analysis. RESULTS: Seventeen patients (6.7%) developed ONJ: 11 of 111 (9.9%) with multiple myeloma, two of 70 (2.9%) with breast cancer, three of 46 (6.5%) with prostate cancer, and one of 25 (4%) with other neoplasms (P = .289). The median number of treatment cycles and time of exposure to bisphosphonates were 35 infusions and 39.3 months for patients with ONJ compared with 15 infusions (P < .001) and 19 months (P = .001), respectively, for patients with no ONJ. The incidence of ONJ increased with time to exposure from 1.5% among patients treated for 4 to 12 months to 7.7% for treatment of 37 to 48 months. The cumulative hazard was significantly higher with zoledronic acid compared with pamidronate alone or pamidronate and zoledronic acid sequentially (P < .001). All but two patients with ONJ had a history of dental procedures within the last year or use of dentures. CONCLUSION: The use of bisphosphonates seems to be associated with the development of ONJ. Length of exposure seems to be the most important risk factor for this complication. The type of bisphosphonate may play a role and previous dental procedures may be a precipitating factor.  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