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31.

Background  

Fascin is an actin bundling protein with roles in the formation of cell protrusions and motility of mesenchymal and neuronal cells. Fascin is normally low or absent from epithelia, but is upregulated in several epithelial neoplasms where it may contribute to an invasive phenotype. Here, we report on the prevalence and potential clinical significance of fascin expression in relation to the progression of colorectal adenocarcinoma and to tumor cell proliferation as measured by Ki67 index.  相似文献   
32.
Ovarian follicles obtained from second and third-trimester human fetuses survived 4 weeks in organ culture and secreted 17-beta estradiol (E(2)).  相似文献   
33.
The identity of the enzyme responsible for the S-oxidation of the mucolytic S-substituted L-cysteine drug, S-carboxymethyl-L-cysteine (SCMC), has been actively investigated for the last 10 years. A genetic polymorphism exists in the oxidation of the thioether moiety that has been identified as a disease susceptibility factor in a number of degenerative diseases. This polymorphism has also been implicated in the wide variation in clinical response to SCMC therapy in man. To date little is known about the molecular enzymology of this reaction but a previous investigation revealed that rat activated phenylalanine 4-monooxygenase (PAH) could S-oxidise both Met- and S-methyl-L-cysteine (SMC) to their S-oxide metabolites. We have investigated the hypothesis that SCMC was also a substrate for activated PAH in the cytosolic faction of the Wistar rat. 1. Substrate and inhibitor investigation revealed that SCMC was a substrate for activated PAH activity in vitro. 2. The large aromatic amino acid hydroxylase monoclonal antibody and the Fe3+ chelator, deferoxamine, completely inhibited both Phe and SCMC oxidation to their respective metabolites. 3. Analysis of the Dixon plots revealed that both Phe and SCMC competitively inhibited each other's oxidation. 4. Correlation studies showed that the rate of production of Tyr was positively correlated to the production of both SCMC and SMC S-oxides in 20 female Wistar rat hepatic cytosolic fractions. These results strongly support the hypothesis that PAH is the enzyme responsible for SCMC S-oxidation in the rat.  相似文献   
34.
The sexually transmitted infections pose a real public health problem, mainly in developing countries. In Tunisia, the epidemiological state is not precise. The objective of our study was to determine the sociological, epidemiological and bacteriological characteristics of gonococcal urethritis in the area of Sfax. The study was performed on all patients attending at the CNSS of Sfax for urethritis for 5 years, from 1996 to 2000. A urethral swab was carried out for each patient with a classic bacteriological exam. 256 cases were collected. The mean age was 29.7 years. 74.3% were workers. The direct exam was positive in 51.2% of cases and the culture enabled us to isolate 72 strains, of which 15.5% were productive of beta-lactamase and 23.9% were resistant to tetracyclin. There was no resistance to pristinamycin, ofloxacin nor spectinomycin.  相似文献   
35.
Our knowlcwdge about the genetic basis of head and neck tumours is accumulating fast. This article reviews the important advances in this area over the last decade and its implications for the future. Newer aspects of gene therapy, molecular staging and understanding head and neck carcinogenesis on a molecular level are outlined.  相似文献   
36.
37.
Recent biological studies have classified breast carcinomas into HER2-overexpressing, estrogen receptor-positive/luminal, basal- and normal-like groups. According to this new biological classification, the objectives of our study were to assess the clinical, morphologic and immunophenotypic characteristics of adenoid cystic carcinoma of the breast in order to classify this subtype of breast carcinoma. A total of 18 cases of adenoid cystic carcinoma were identified from the Institut Curie files. Clinical information was available for 16 patients with a median follow-up of 6.5 years. Morphologically, all tumors were graded according to the system defined by Kleer and Oberman (histologic and nuclear grade). Immunophenotype was assessed with anti-ER, PR, HER-2, KIT, basal (CK5/6) and luminal cytokeratins (CK8/18) and p63 antibodies. One out of 18 tumors was nuclear grade 1 (16%), nine were nuclear grade 2 (50%) and eight were nuclear grade 3 (44%). All cases were estrogen receptor, progesterone receptor and HER-2 negative. Epithelial cells were strongly positive around glandular lumina with one or both cytokeratins, identifying the coexistence of CK5/6+ cells, CK5/6 and CK8/18+ cells, CK8/18+ cells and p63+ cells. All cases (100%) were also KIT positive. In all, 15 patients were treated by surgery. Nine of them received adjuvant radiotherapy. Follow-up was available for 16 patients. In all, 14 patients were alive. Two of them, initially treated by surgery only, presented a local recurrence. Two patients died (one of them treated by radiation therapy only died from her disease). Our study shows that adenoid cystic carcinoma of the breast is a special, estrogen receptor, progesterone receptor, HER-2 negative and highly KIT-positive, basal-like breast carcinoma, associated with an excellent prognosis. This highly specific immunophenotype could be useful to differentiate adenoid cystic carcinoma of the breast from other subtypes of breast carcinoma such as cribriform carcinoma.  相似文献   
38.
TOPIC. Loneliness is a universal human experience recognized since the dawn of time, yet it is unique for every individual. Loneliness can lead to both depression and low self‐esteem. PURPOSE. This article explicates the concept of loneliness through the examination of its conceptual definition and uses, defining attributes, related concepts, and empirical referents. SOURCES OF INFORMATION. Literature review using hand search and database were used as sources of information. CONCLUSION. Because loneliness is commonly encountered in nursing situations, the information provided will serve as a framework for assessment, planning, intervention, and evaluation of clients.  相似文献   
39.
In a randomized trial of a clinical decision support system for drug prescribing for residents with renal insufficiency in a large long-term care facility, analyses were conducted to estimate the system's immediate, direct financial impact. We determined the costs that would have been incurred if drug orders that triggered the alert system had actually been completed compared to the costs of the final submitted orders and then compared intervention units to control units. The costs incurred by additional laboratory testing that resulted from alerts were also estimated. Drug orders were conservatively assigned a duration of 30 days of use for a chronic drug and 10 days for antibiotics. It was determined that there were modest reductions in drug costs, partially offset by an increase in laboratory-related costs. Overall, there was a reduction in direct costs (US$1391.43, net 7.6% reduction). However, sensitivity analyses based on alternative estimates of duration of drug use suggested a reduction as high as US$7998.33 if orders for non-antibiotic drugs were assumed to be continued for 180 days. The authors conclude that the immediate and direct financial impact of a clinical decision support system for medication ordering for residents with renal insufficiency is modest and that the primary motivation for such efforts must be to improve the quality and safety of medication ordering.  相似文献   
40.
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