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   103篇
  免费   11篇
  国内免费   1篇
儿科学   12篇
基础医学   5篇
口腔科学   4篇
临床医学   10篇
内科学   26篇
皮肤病学   12篇
神经病学   11篇
特种医学   1篇
外科学   9篇
综合类   1篇
预防医学   3篇
药学   7篇
肿瘤学   14篇
  2022年   1篇
  2021年   1篇
  2017年   1篇
  2016年   2篇
  2015年   6篇
  2014年   2篇
  2013年   2篇
  2012年   2篇
  2011年   1篇
  2010年   4篇
  2009年   3篇
  2008年   1篇
  2007年   7篇
  2006年   5篇
  2005年   5篇
  2004年   2篇
  2003年   6篇
  2002年   1篇
  1999年   7篇
  1998年   7篇
  1997年   4篇
  1996年   3篇
  1995年   3篇
  1994年   5篇
  1993年   4篇
  1992年   6篇
  1991年   1篇
  1988年   1篇
  1984年   1篇
  1980年   1篇
  1979年   1篇
  1974年   1篇
  1959年   1篇
  1957年   6篇
  1956年   4篇
  1955年   3篇
  1954年   3篇
  1937年   1篇
排序方式: 共有115条查询结果,搜索用时 15 毫秒
1.
Background: Olfactory neuroblastoma is a rare sino‐nasal tumor arising from the olfactory epithelium and is often characterized by local invasion or metastasis. The role of chemotherapy in the treatment of this tumor is unclear. The purpose of this study was to review our institution’s experience of chemotherapy for advanced or recurrent olfactory neuroblastoma. Methods: Twenty‐one patients with histologically proven olfactory neuroblastoma were treated at our institution between 1992 and 2002. Twelve of these patients received chemotherapy in the setting of unresectable or recurrent disease and were retrospectively reviewed for clinical characteristics, treatment outcome or survival. Results: Eight patients of the 12 patients received cisplatin‐based chemotherapy and the remaining four patients received chemotherapy consisting of docetaxel plus irinotecan (three patients) or cyclophosphamide, doxorubicin, and vincristine (1 patient). A partial response was achieved in five patients, with an overall response rate of 42%, although the chemotherapeutic regimens were heterogeneous. Two partial responses were obtained among the three patients who received docetaxel plus irinotecan. The response rate to chemotherapy was 83% in the younger age group (<40 years), as opposed to 0% in the older age group (≥40 years), and the difference between the two groups was statistically significant (P = 0.02). Conclusion: Our study indicated that olfactory neuroblastoma would be sensitive to chemotherapy, especially with young patients. Docetaxel plus irinotecan has the possibility of showing favorable response, and warrants further investigation.  相似文献   
2.
BACKGROUND: Decreased energy expenditure and increased food intake are principal causes for obesity. In the present study, genotypes of beta(3)-adrenergic receptor (beta(3)AR) and of melanocortin-4 receptor (MC4R), both of which are believed to have a close link to the cause of obesity, were analyzed and compared with phenotypes of childhood obesity. METHODS: Thirty-five obese children with moderate to severe obesity were enrolled. Direct sequencing of the MC4R coding region and pinpoint-polymerase chain reaction were used to detect genomic variation in the beta(3)AR gene using peripheral blood-derived DNA. RESULTS: Allele frequency of Trp64Arg variation in the beta(3)AR gene in the obese subjects was 0.16, which is comparable with that in the healthy general population in eastern Asia. Comparison of phenotypical characteristics did not show a significant difference between Trp/Trp and Trp/Arg subjects. It was notable that body height SD was significantly higher in the Trp/Trp than the Trp/Arg subjects (0.93 +/- 1.0 SD vs 0.07 +/- 1.3 SD, P= 0.03). Annual weight gains were far beyond a hypothetical fat gain in an Arg64 heterozygote with decreased energy consumption, suggesting increased food intake in childhood obesity. There was, however, no variation in the MC4R gene despite thorough sequencing of the entire coding region. CONCLUSIONS: The Trp64Arg variation in the beta(3)AR gene has no relationship to the degree or the incidence of childhood obesity. The majority of childhood obesity can be characterized as tall stature, more rapid weight gain than that expected by decreased energy expenditure. Further investigation is necessary in regard to the increased food intake as a major cause of childhood obesity.  相似文献   
3.
Neutrophilic dermatoses (ND), with or without accompanying myelodysplastic syndrome (MDS), were examined in terms of nuclear abnormality like pelgeroid anomaly of infiltrating cells into skin lesions. Six ND accompanying MDS showed 1.0 to 13.5% of such anomalous cells among infiltrating cells. In contrast, ND without accompanying myeloproliferative disorders rarely had such anomalous cells. Our findings suggest that pelgeroid-like anomalous cells infiltrating into ND are probably a good marker of underlying MDS.  相似文献   
4.
Background : We newly synthesized YF476 ((R)-1-[2,3-dihydro-2-oxo-1-pivaloylmethyl-5-(2'-pyridyl)-1H-1,4-benzodiazepin-3-yl]-3-(3-methylamino-phenyl)urea) as a gastrin/cholecystokinin-B (CCK-B) receptor antagonist. We investigated the pharmacological profile of YF476 in vitro and in vivo .
Methods : We examined the binding properties of YF476 to the rat brain, cloned canine and cloned human gastrin/CCK-B receptors, and the effect of YF476 on secretagogue-induced gastric acid secretion in rats and Heidenhain pouch dogs.
Results : YF476 replaced the specific binding of [125I]CCK-8 to the rat brain, cloned canine and cloned human gastrin/CCK-B receptors, with K i values of 0.068, 0.62 and 0.19 n M , respectively. The affinity of YF476 for rat brain gastrin/CCK-B receptor was 4100-fold higher than that for rat pancreatic CCK-A receptor. In anaesthetized rats, intravenous YF476 inhibited pentagastrin-induced acid secretion with an ED 50 value of 0.0086 μmol/kg, but did not affect histamine- and bethanechol-induced acid secretion at a dose of 10 μmol/kg. In Heidenhain pouch dogs, intravenous and oral YF476 inhibited pentagastrin-stimulated gastric acid secretion in a dose-dependent manner with ED 50 values of 0.018 and 0.020 μmol/kg, respectively, but did not affect histamine-induced acid secretion.
Conclusion : These results suggest that YF476 is an extremely potent and highly selective gastrin/CCK-B receptor antagonist, and that the gastrin/CCK-B receptor is not involved in histamine- or bethanechol-induced gastric acid secretion in dogs or rats.  相似文献   
5.
Genetic factors related to the development of alcoholic liverand pancreatic diseases (ALD and APD) and of alcohol-inducedasthma were analyzed. The development of ALD is geneticallycontrolled and is directly associated with the polymorphismsof the genes of acetaldehyde (Ac-CHO) and ethanol-metabolizingenzymes, aldehyde dehydrogenase-2 (ALDH2) and cytochrome P4502E1.The development of ALD and APD may also be genetically linkedwith the induction of gamma-glutamyl transferase (GTT) by alcohol.Alcohol-induced asthma is related to the genotypes of ALDH2and is caused by rapid elevation of blood Ac-CHO. ALDH1 playsa very important role in the oxidation of Ac CHO in blood.  相似文献   
6.
Combined Repeat Dose and Reproductive/Developmental ToxicityScreening Test (OECD): Familiarization Using Cyclophosphamide.TANAKA, S., KAWASHIMA, K., NAITO, K., USAMI, M., NAKADATE, M.,IMAIDA, K., TAKAHASHI, M., HAYASHI, Y., KUROKAWA, Y., AND TOBE,M. (1992A, Y., AND TOBE, M. (1992). Fundam. Appl. Toxicol. 18,89–95. A familiarization study was conducted on the "Combined RepeatDose and Reproductive/Developmental Toxicity Screening Test(ReproTox)" proposed by the OECD. Cyclophosphamide (CP) at dosesof 6.7, 4.5, 3, 2, and 0 mg/kg body wt was given daily by gavageto groups of 12 male and 12 female Sprague-Dawley rats. As aresult, anemia and leukopenia were evident in treated males.The absolute and relative thymus and spleen weights were decreasedin treated rats. Histopathologically, atrophy of the thymus,spleen, and bone marrow was observed. With respect to the reproductive/developmentaltoxicity, dose-dependent increases in postimplantation lossof fetuses and postnatal death were found in dams given CP.The body weight of pups treated with CP was significantly loweredin a dose-related manner. Thus the results demonstrated mostof the known toxicological properties of CP, except the adverseeffects on spermatogenesis and fertility. Therefore ReproToxcan be considered as a useful screening test for assessing repeatdose and reproductive/developmental toxicity of existing chemicalsof high production volume.  相似文献   
7.
谷胱甘肽对顺铂致猴和大鼠肾细胞毒性的影响   总被引:1,自引:1,他引:1  
目的 探讨顺铂对猴和大鼠肾小管上皮细胞的毒性及半胱氨酸和GSH合成抑制剂BSO对其影响。方法 从猴和大鼠的肾脏分离培养的肾小管上皮细胞接种于96孔培养板,培养24h后加入一系列浓度的顺铂,或在加入顺铂前16和4h,分别加入GSH合成抑制剂BSO和GSH的前体物半胱氨酸,继续培养,分别在8、24和48h3个时间点用MTT方法检测细胞存活率。结果 顺铂对猴和大鼠肾小管上皮细胞有明显的毒性,在不同的时间点有各自的剂量—反应关系,顺铂对大鼠肾小管上皮细胞在8、24和48h 3个时间点半数抑制浓度(IC50)分别为1105.12、513.25和71.24μmol/L;BSO能使3组IC50均降低,分别为66.00、21.43和7.23μmol/L,而半胱氨酸则使3组IC50均升高,均大于5000μmol/L;顺铂对猴肾小管上皮细胞在3个时间点IC50分别为3026.00、1238.35和664.44μmol/L;BS0使3组ICD分别降为480.10、108.61和31.43μmol/L,而半胱氨酸则可使3组IC50均大于5000μmol/L。结论 顺铂对猴和大鼠肾小管上皮细胞均具有明显毒性作用,对猴的毒性低于大鼠;BS0可增强顺铂的细胞毒性,对大鼠的影响大于猴,而半胱氨酸对两种细胞的保护作用无显著性差异,提示细胞内GSH对顺铂所致肾小管上皮细胞毒性有保护作用。  相似文献   
8.
9.
MDCT/MRI Fusion for the Guidance of VT Ablation . Background: Delayed enhancement (DE) MRI can assess the fibrotic substrate of scar‐related VT. MDCT has the advantage of inframillimetric spatial resolution and better 3D reconstructions. We sought to evaluate the feasibility and usefulness of integrating merged MDCT/MRI data in 3D‐mapping systems for structure–function assessment and multimodal guidance of VT mapping and ablation. Methods: Nine patients, including 3 ischemic cardiomyopathy (ICM), 3 nonischemic cardiomyopathy (NICM), 2 myocarditis, and 1 redo procedure for idiopathic VT, underwent MRI and MDCT before VT ablation. Merged MRI/MDCT data were integrated in 3D‐mapping systems and registered to high‐density endocardial and epicardial maps. Low‐voltage areas (<1.5 mV) and local abnormal ventricular activities (LAVA) during sinus rhythm were correlated to DE at MRI, and wall‐thinning (WT) at MDCT. Results: Endocardium and epicardium were mapped with 391 ± 388 and 1098 ± 734 points per map, respectively. Registration of MDCT allowed visualization of coronary arteries during epicardial mapping/ablation. In the idiopathic patient, integration of MRI data identified previously ablated regions. In ICM patients, both DE at MRI and WT at MDCT matched areas of low voltage (overlap 94 ± 6% and 79 ± 5%, respectively). In NICM patients, wall‐thinning areas matched areas of low voltage (overlap 63 ± 21%). In patients with myocarditis, subepicardial DE matched areas of epicardial low voltage (overlap 92 ± 12%). A total number of 266 LAVA sites were found in 7/9 patients. All LAVA sites were associated to structural substrate at imaging (90% inside, 100% within 18 mm). Conclusion: The integration of merged MDCT and DEMRI data is feasible and allows combining substrate assessment with high‐spatial resolution to better define structure–function relationship in scar‐related VT. (J Cardiovasc Electrophysiol, Vol. 24, pp. 419‐426, April 2013)  相似文献   
10.
目的: 探讨转录调控因子CBF1(C-promoter binding factor-1, CBF1)在成鼠骨组织以及小鼠胚胎性骨组织的表达情况.方法: 采用实时RT-PCR方法检测包括骨组织在内的成年小鼠13种器官组织中CBF1的相对表达水平.采用组织原位杂交技术检测小鼠胚胎性趾骨、肋骨和椎骨中CBF1的分布.结果: 转录调控因子CBF1在成年小鼠各组织器官中广泛存在,在骨组织中检测到较高的CBF1表达水平.原位杂交分析显示: 发育中的趾骨和肋骨软骨细胞CBF1阳性染色,染色阳性程度与软骨细胞的分化程度有关;肋骨和椎骨骨化区周围成骨细胞呈强阳性染色;埋入骨基质的骨细胞则呈弱阳性染色.结论: 转录调控因子CBF1参与了小鼠骨组织的发育形成,可能也参与了成熟骨组织的改建和代谢.  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