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   168篇
  免费   6篇
基础医学   53篇
口腔科学   5篇
临床医学   11篇
内科学   17篇
皮肤病学   4篇
神经病学   3篇
特种医学   3篇
外科学   11篇
综合类   2篇
预防医学   14篇
药学   2篇
肿瘤学   49篇
  2021年   2篇
  2020年   1篇
  2014年   2篇
  2013年   2篇
  2012年   1篇
  2011年   3篇
  2010年   2篇
  2009年   3篇
  2008年   5篇
  2007年   5篇
  2006年   5篇
  2005年   9篇
  2004年   9篇
  2003年   6篇
  2002年   5篇
  2001年   10篇
  2000年   7篇
  1999年   12篇
  1998年   5篇
  1997年   7篇
  1996年   7篇
  1995年   5篇
  1994年   3篇
  1993年   2篇
  1992年   8篇
  1991年   3篇
  1990年   2篇
  1988年   3篇
  1987年   4篇
  1986年   5篇
  1985年   3篇
  1984年   5篇
  1983年   3篇
  1982年   1篇
  1981年   1篇
  1980年   5篇
  1979年   5篇
  1978年   2篇
  1975年   1篇
  1974年   1篇
  1973年   3篇
  1972年   1篇
排序方式: 共有174条查询结果,搜索用时 15 毫秒
31.
We have previously shown that HCR is a good candidate gene for psoriasis based on its location in the PSORS1 locus, predicted secondary structure change of the associated allele, and expression pattern. To understand better the function of HCR, we studied how HCR expression is altered in hyperproliferative skin diseases other than psoriasis and in cancers. We examined also its regulation by different cytokines, growth factors, and antipsoriatic agents using quantitative RT-PCR (TaqMan) analysis and its location by immunostaining of keratinocyte cultures. Compared to psoriasis, HCR protein had a different distribution in chronic dermatitis, pityriasis rubra pilaris, mycosis fungoides, and chronic skin ulcers. In three of six grade III squamous cell carcinomas of the skin, four of four adenocarcinomas of the lung, and two of two ductal breast adenocarcinomas, positive cytoplasmic staining in cancer cells was detected. As in psoriasis, Ki67 did not colocalize with HCR. In cell cultures, HCR staining was detected perinuclearly in the cytoplasm and in the nuclei, suggesting that the protein may have a role in both compartments. A 2-fold downregulation of HCR mRNA expression was observed on stimulation with interferon-gamma. Based on the observations that HCR is detected in cancers of epithelial origin in Ki67-negative areas and that interferon-gamma downregulates its expression, we suggest it to have an antiproliferative function.  相似文献   
32.
We present the 5-year results of the effect of adjuvant chemotherapy on bone mineral density (BMD) and the efficacy of clodronate in the prevention of bone loss in 73 premenopausal women with primary breast cancer. All patients were treated with cyclophosphamide, methotrexate, 5-fluorouracil (CMF) chemotherapy. The patients were randomised to oral clodronate 1600 mg daily for 3 years or to a control group. At 5 years, patients were divided into those with preserved menstruation and those with amenorrhoea. Changes in BMD correlated significantly with the menstrual function after chemotherapy. The change in the lumbar spine BMD at 3 and 5 years were +0.6 and −1.3% in the menstruating group and −7.5 and −10.4% in the amenorrhoeic group (P=0.0001 and 0.0001, respectively), and in femoral neck +1.7 and −0.3%, and −3.5 and −5.8% (P=0.002 and P=0.001, respectively). Three-year clodronate treatment significantly reduced the bone loss in the lumbar spine −3.0% compared with controls −7.4% at three years (P=0.003), but no significant difference was found in the femoral neck: −1.7% versus −2.8%, respectively (P=0.86). These differences between the study groups were still seen at 5 years: in the lumbar spine −5.8% versus −9.7% (P=0.008) and femoral neck −3.5% versus −5.1% (P=0.91). In conclusion, chemotherapy-induced ovarian failure in premenopausal women caused a temporary accelerated bone loss of the lumbar spine. Adjuvant clodronate treatment significantly reduced this bone loss. Two years after the termination of treatment, the bone loss was still significantly less in the clodronate group compared with the control group.  相似文献   
33.
Comparative genomic hybridization of postirradiation sarcomas.   总被引:2,自引:0,他引:2  
BACKGROUND: Radiotherapy is a known risk factor for sarcoma development. Postirradiation sarcomas arise within the radiation field after a latency period of several years and usually are highly malignant. Very little is yet known about their genetic changes. METHODS: Twenty-seven postirradiation sarcomas were analyzed by comparative genomic hybridization, which allows genome-wide screening of DNA sequence copy number changes. RESULTS: Copy-number aberrations were detected in 20 (74%) tumors. The mean number of aberrations per tumor was 5.3 with gains outnumbering losses. The most frequent gains affected the minimal common regions of 7q11.2-q21 and 7q22 in 30% and 7p15-pter in 26%. Gain of 8q23-qter was detected in 22%. The most frequent losses affected 11q23-qter and 13q22-q32 in 22%. In osteosarcomas, the most frequent aberration was loss of 1p21-p31, in malignant fibrous histiocytomas (MFH) gain of 7cen-q22, and in fibrosarcomas gain of 7q22. The findings in postirradiation osteosarcomas and MFHs were compared with findings in sporadic osteosarcomas and MFHs, reported previously by the authors. In sporadic osteosarcomas, gains outnumbered losses, but, in postirradiation osteosarcomas, losses were more frequent than gains. Loss at 1p was rare in sporadic osteosarcoma (3%) but frequent (57%) in postirradiation osteosarcomas. Gains at 7q were frequent both in postirradiation and sporadic MFH. CONCLUSIONS: According to previous studies on different types of sporadic sarcomas, gains at 7q or 8q are associated with poor prognosis or large tumor size. Thus, the frequent gains at 7q and 8q might have been responsible in part for the poor prognosis of postirradiation sarcomas. Also, however, some of their clinical features, i.e., high malignancy grade, late diagnosis, and central location, are associated with a poor prognosis.  相似文献   
34.
35.
Clodronate, one of the most investigated bisphosphonates, has been clinically utilised for over 10 years in malignancy. It is the most used, most effective and safest drug in the treatment of hypercalcaemia. It inhibits lytic bone destruction, prevents bone fractures and relieves bone pain. Supportive clodronate therapy may even reduce hypercalcaemia mortality and the morbidity caused by osteolysis. These results have stimulated studies on the patients' quality of life. New methods for the measurement of bone resorption, such as the degradation product of type I collagen (ICTP), may improve the possibility of monitoring the effect of clodronate. Comparative studies with different bisphosphonates in hypercalcaemia and long-term controlled trials using bisphosphonates as supportive therapy in osteolysis due to malignancy are reviewed.  相似文献   
36.
37.
Aminoglutethimide (AG) and hydrocortisone (HC) were given to 20 patients with advanced prostatic cancer resistant to conventional hormonal therapy. Most patients had painful bone metastases and were heavily pretreated. 12 of 16 patients required narcotic analgetics. 8 of 20 were bedridden. AG + HC produced relief of bone pain in 12 patients (75%) and only 4 required narcotics after treatment. The performance status improved in 8 of 20 patients (40%). However, the number of bone metastases seen in bone scans decreased in only 4 patients (22%). The level of serum alkaline phosphatase decreased in 11 of 18 patients and that of acid phosphatase in 8 of 16 patients. The reduction of bone pain lasted approximately 4 months (range 1-15 months). The median lifespan between the start of AG treatment and death was 8 months (range 2-22 months). There was no difference in survival between responders and nonresponders. 3 patients had skin rash, 1 lethargy and 1 thrombocytopenia.  相似文献   
38.
We studied the pharmacokinetics of 7 alpha-methyl-19-nortestosterone (MENT), a potent synthetic androgen, administered by subdermal implants. The implants contained 112 +/- 4 mg of MENT acetate in a polyethylene vinyl acetate copolymer. MENT acetate released from the implants is rapidly hydrolyzed to MENT in vivo. Fifteen healthy Finnish men were randomized to have either one, two, or four implants inserted in the medial aspect of the upper arm. The implants remained in place for 4 weeks. Blood samples were obtained before implant insertion, 1, 2, 3, and 4 weeks after insertion, and 1 and 2 weeks after removal. Serum MENT concentrations were determined by gas chromatography with mass selective detection. The MENT levels attained in each implant group remained at a steady level during the 4 weeks of implant use. The mean steady state MENT concentrations in the one, two, and four implant groups were 0.6, 1.4, and 2.3 nmol/L, respectively. Serum MENT concentrations during implant use were clearly dose dependent; the between-subject effect of implants as well as the differences between each pair of groups were all statistically significant. The release rate of MENT from one, two, and four implants was calculated to be approximately 0.3, 0.8, and 1.3 mg/day, respectively. This study suggests that MENT acetate implants are a promising method for long-term androgen administration in hypogonadism and male contraception.  相似文献   
39.
Microsatellite instability has recently been reported in sporadic and familial colorectal tumours and can be due to defects in DNA mismatch repair genes. Such instability has subsequently been detected in several other types of sporadic tumours. We studied 29 specimens of bone tumours with different histopathological diagnoses and found no evidence of microsatellite instability. Our results suggest that mismatch repair defects are unlikely to play a significant part in the tumorigenesis of bone neoplasms. Loss of heterozygosity with at least one marker was detected in 11, i.e. in 38% of the tumour samples, most frequently with markers D2S136 at 2p (eight of 28 informative specimens, 29%) and D11S904 at 11p (four of 21 informative specimens, 19%).  相似文献   
40.
We used pulsed-field gel electrophoresis analysis and genotyping to compare clinical isolates of Bordetella pertussis recovered since the early 1990s in Finland and France, 2 countries with similar histories of long-term mass vaccination with whole-cell pertussis vaccines. Isolates from both countries were similar genetically but varied temporally.  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