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81.
Twenty-four hepatic cavernous hemangiomas and 91 metastases from a variety of hypovascular and hypervascular primary neoplasms were prospectively studied with magnetic resonance (MR) imaging. In addition to qualitative analysis, quantitative analysis of signal intensity ratios of lesion to normal liver was performed with images obtained with 500/28-30 (repetition time msec/echo time msec) and 2,000/28-150 sequences. Quantitative data did not improve the ability to distinguish hemangiomas from metastases in our series compared with qualitative analysis. Hypovascular metastases, such as colon carcinoma, could be differentiated from hemangioma more frequently (97.5%) than hypervascular endocrine metastases, such as islet cell tumor, carcinoid, and pheochromocytoma (61%). These findings indicate that the utility of MR imaging in differentiating hemangiomas from metastases is dependent on the histologic type of the primary neoplasm.  相似文献   
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Duodenal neoplasms: role of CT   总被引:5,自引:0,他引:5  
In a retrospective study of 14 cases of duodenal neoplasms evaluated by computed tomography (CT), there were four primary adenocarcinomas of the duodenum, one lymphoma, five metastatic carcinomas, two duodenal lipomas, one villous adenoma, and one leiomyoma. The CT findings were diagnostic in patients with duodenal lipomas. In 11 cases, a primary origin of the mass was clearly identifiable in the duodenum. Thickening of the bowel wall, tumor necrosis, ulceration, and intraluminal defects were common. The relationship of the masses to adjacent structures was clearly shown on CT scans. Extraluminal extent of the lesion was noted on CT scans in seven patients; however, at surgery only four of six were found to have extramural disease. The presence of adenopathy, liver metastases, and vascular and mesenteric invasion were also demonstrated on CT scans. Twelve patients underwent upper gastrointestinal tract series. A duodenal abnormality was seen in all 12 patients, but the extramural extent and distant metastatic involvement could not be seen on these examinations. CT scans allowed the accurate staging of eight of ten malignant lesions and thus helped in the management of duodenal tumors.  相似文献   
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Minor products of reaction of DNA with alpha-acetoxytamoxifen   总被引:1,自引:0,他引:1  
The drug tamoxifen shows evidence of genotoxicity and induces liver tumours in rats. Covalent DNA adducts have been detected in the liver of rats treated with tamoxifen and these arise, at least in part, from its metabolite alpha-hydroxytamoxifen. This probably undergoes conjugation in the liver tissue to give an ester, which alkylates DNA. We have prepared alpha-acetoxytamoxifen as a model for this reactive intermediate and studied its reaction with DNA in vitro. The products of this reaction were chromatographically identical to DNA adducts found in the liver of rats treated with tamoxifen. We have isolated three of these products as the nucleosides TG1, TG2 and TA1 and identified them by ultraviolet, mass and proton magnetic resonance spectroscopy. TG1 and TG2 were tamoxifen-deoxyguanosine adducts in which the alpha-position of tamoxifen was linked to the amino group of guanine; TG1, (E)-4-[4-[2-(dimethylamino)ethoxy]phenyl]-3,4-diphenyl-2- (9beta-de oxyribofuranosyl-6-oxopurin-2-ylamino)-3-butene; TG2, (Z) isomer of TG1. In TG2, the tamoxifen group had undergone trans-cis isomerization. The minor product TA1 was a tamoxifen-deoxyadenosine adduct, where linkage was through the amino group of adenine: (E)-4-[4- [2-(dimethylamino) ethoxy]phenyl]-3,4-diphenyl-2-(9beta- deoxyribofuranosylpurin -6-ylamino)-3-butene. These three adducts accounted for >90% of the reaction products (approximately 67% TG1, 18% TG2 and 7% TA1); trace products included other stereoisomers of these and dinucleotide adducts which resisted enzymatic digestion.   相似文献   
88.
Gazdar  AF; Oie  HK; Kirsch  IR; Hollis  GF 《Blood》1986,67(6):1542-1549
Using a serum-free defined medium, we have established a human cell line, NCI-H929, from a malignant effusion occurring in a patient with IgAk myeloma. The cultured cells have the morphologic, ultrastructural, biochemical, immunologic, and cytochemical features of plasma cells. The cells have rearranged alpha and kappa genes and synthesize and secrete high amounts of IgAk (greater than 80 micrograms/10(6) cells per 24 hours). The cells express surface immunoglobulin (alpha and kappa), the plasma cell antigen PCA-1, the transferrin receptor (T9) and T10 but lack antigens associated with earlier stages of B cell development (HLA-DR, B1, B2, B4, CALLA), as well as other leukocyte- macrophage antigens and Epstein-Barr virus (EBV) nuclear antigen. Although molecular studies confirm that both the tumor and cultured cells are derived from the same clone of malignant B cells, the tumor cells were predominantly near-diploid, whereas the cultured cells are predominantly near-tetraploid with six copies of chromosome 8, four to six of which have an 8q + abnormality. However, both the tumor and the cultured cells have a rearrangement of the cellular c-myc proto- oncogene (located at 8q24) and express c-myc RNA. Although a modest number of human "plasmacytoid" cell lines have been established, most are lymphoblastoid lines lacking plasma cell features, while others appear to be early secretory cells. In contrast, NCI-H929 is a differentiated, highly secretory human plasma cell line.  相似文献   
89.
目的:研究尼日利亚阿巴卡利基地区儿童眼病的分布特点。 方法:回顾过去15mo就诊于阿巴卡利基联邦医疗中心眼科门诊的15岁及以下儿童的就诊资料,分析阿巴卡利基地区儿童眼病的分布规律。 结果:241位儿童纳入了本次研究。其中男112位为(46.5%),女129位(53.5%)。儿童眼病主要以过敏性结膜炎、屈光不正、感染性结膜炎、眼球挫伤为主。其中过敏性结膜炎患者91人(37.8%),屈光不正37人(15.4名),感染性结膜炎30人(12.4%),眼球挫伤的患者27人(11.2%)。 结论:过敏性结膜炎及屈光不正为阿巴卡利基地区儿童常见的眼病。学前儿童进行眼科检查能有效的早期诊断治疗儿童眼病的发生,并能有效地预防其并发症的发生。  相似文献   
90.
Growth in Crohn's disease   总被引:2,自引:0,他引:2  
Savage MO, Beattie RM, Camacho-Hubner C, Walker-Smith JA, Sanderson IR. Growth in Crohn's disease. Acta Paediatr 1999; Suppl 428:89-92. Stockholm. ISSN 0803-5326
Abnormal linear growth is frequent in children and adolescents with Crohn's disease. The typical pattern is of growth retardation associated with delayed skeletal maturation. Puberty is also frequently delayed. Over 50% of patients may have a subnormal height velocity, and approximately 25% will have short stature. The endocrine status is characterized by normal growth hormone secretion and a slightly subnormal serum level of insulin-like growth factor I, which is related to nutritional status. Principal therapeutic options are intestinal resection for localized disease, and enteral nutrition - using a polymeric diet - for more widespread disease, particularly involving the small intestine. Growth responses to both modalities are often excellent and produce considerable psychological benefit. Optimum therapy is achieved by close collaboration between gastroenterologists and endocrinologists, and by the use of auxologicalmethods to document pre- and post-therapeutic management. □ Crohn 's disease, enteral nutrition, growth, intestinal resection, puberty  相似文献   
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