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991.
992.
An immunohistochemical study was made of cathepsin-D protein expression in each of the three main types of uterine cervical carcinoma (squamous carcinoma, adenosquamous carcinoma and adenocarcinoma) with particular reference to lymph node status and prognosis. Of the 61 cases, 54.1% showed cytoplasmic staining in more than 2.5% of tumour cells counted. Cathepsin-D expression was significantly higher in adenocarcinoma (mean -3.128) than in squamous carcinoma and adenosquamous carcinoma (mean -3.709, p = 0.047 using logit transformation). Cathepsin-D had no prognostic value in any of the three tumour types. No relationship was found between cathepsin-D staining and lymph node status and there was no advantage in adding cathepsin-D values to lymph node status. These results suggest that immunostaining for cathepsin-D protein expression is unlikely to be of use as a prognostic marker. 相似文献
993.
extradenticle (exd) and the homeotic selector proteins together establish segmental identities by coordinately regulating the expression of downstream target genes. The inappropriate expression of these targets in exd mutant embryos results in homeotic transformations and aberrant morphogenesis. Here we examine the role of exd in adult development by using genetic mosaics and a hypomorphic exd allele caused by a point mutation in the homeodomain. exd continues to be essential for the specification of segmental identities, consistent with a continuing requirement for exd as cofactor of the homeotic selector proteins. Loss of exd results in the homeotic transformation of abdominal segments to an A5 or A6 segmental identity, the antenna and arista to leg, and the head capsule to dorsal thorax or notum. Proximal leg structures are particularly sensitive to the loss of exd, although exd does not affect the allocation of proximal positional values of the leg imaginal disc. Using heat-shocks to induce expression of a hsp70-exd fusion gene, we show that, in contrast to the homeotic selector genes, ubiquitously high levels of exd expression do not cause pattern abnormalities or segmental transformations. 相似文献
994.
Wnt signaling: a common theme in animal development 总被引:5,自引:0,他引:5
995.
996.
997.
OBJECTIVES: Most national dietary studies have reported inadequate calcium (Ca) intake by women, indicating that marketing and educational efforts have not effected dietary behavior changes. The purpose of this study was to identify knowledge, attitudes, and behaviors which influence dairy Ca intake. METHODS: A questionnaire was developed to accomplish these objectives, and piloted for clarity and content validity. Dietary Ca intake was assessed using a food frequency questionnaire. After revisions, women were sampled from four sources: a health spa, elderhostel classes, through a Cooperative Extension Service program, and from the Illinois Older Women's League. The response rate was 66.5%. RESULTS: Mean total reported Ca intake (n = 351) was 591 +/- 355 mg/day. Over 40% of the women reported Ca intakes below 60% of the RDA and could therefore be considered to have deficient intake. Unfortunately, 27.1% of these with deficient intake believed they were meeting the Ca RDA. Significant differences (p < or = 0.01) were found in attitudes and beliefs about dairy Ca when comparing women whose intake was below 60% of the RDA with those whose intake was above 60%. The most commonly mentioned beliefs of the entire sample concerned cholesterol (16.5%), high calories (13.7%) and gastrointestinal discomfort (12.8%). CONCLUSIONS: These findings suggest an important discrepancy between perceived and actual Ca intake which could influence receptiveness to education. Non-dairy Ca rich food sources need to be clarified as does the caloric and cholesterol content of dairy foods. 相似文献
998.
Broth formulations of two media selective for enterococci, Enterococcel, M-Enterococcosel broths were supplemented with 6 micrograms of vancomycin per ml and evaluated for isolation of vancomycin-resistant enterococci (VRE). Each broth was challenged with various concentrations of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and vancomycin-susceptible and vancomycin-resistant enterococci and with 193 perianal specimens obtained from patients at risk in our institution for VRE colonization. Both the Enterococcosel and M-Enterococcus broths with vancomycin detected as few as 1 to 9 CFU of VRE while inhibiting growth of the other organisms tested. Enterococcus faecium organisms (MIC, > 256 micrograms/ml) were recovered from 66 perianal swab cultures in the enterococcosel-vancomycin broth, and VRE were recovered from 62 perianal swab cultures in the M-Enterococcus-vancomycin broth. Enterococcosel-vancomycin broth detected VRE in perianal specimens 48 h earlier than did M-Enterococcus-vancomycin broth. Enterococcosel broth with 6 micrograms of vancomycin per ml can be used for the rapid and selective isolation of VRE from surveillance specimens. 相似文献
999.
JJ Mann KM Malone DA Nielsen D Goldman J Erdos J Gelernter 《Canadian Metallurgical Quarterly》1997,154(10):1451-1453
OBJECTIVE: This study was designed to test the hypothesis that serotonin-system-related genes may be correlated with suicide risk. METHOD: Fifty-one unrelated Caucasian inpatients with major depression, with or without a history of suicidal acts, were genotyped for a biallelic polymorphism at the tryptophan hydroxylase locus. RESULTS: The less common tryptophan hydroxylase U allele occurred with greater frequency in the patients who had attempted suicide. A logistic regression analysis confirmed an association between tryptophan hydroxylase genotype and lifetime history of suicide attempts. CONCLUSIONS: Serotonergic-system-related genes may influence the risk of suicide in persons with major depression. 相似文献
1000.
A Citrobacter sp. accumulates uranyl ion (UO2(2+)) as crystalline HUO2PO4.4H2O (HUP), using enzymatically generated inorganic phosphate. Ni was not removed by this mechanism, but cells already loaded with HUP removed Ni2+ by intercalative ion-exchange, forming Ni(UO2PO4)2.7H2O, as concluded by x-ray diffraction (XRD) and proton induced x-ray emission (PIXE) analyses. The loaded biomass became saturated with Ni rapidly, with a molar ratio of Ni:U in the cellbound deposit of approx. 1:6; Ni penetration was probably surface-localized. Cochallenge of the cells with Ni2+ and UO2(2+), and glycerol 2-phosphate (phosphate donor for phosphate release and metal bioprecipitation) gave sustained removal of both metals in a flow through bioreactor, with more extensively accumulated Ni. We propose 'Microbially Enhanced Chemisorption of Heavy Metals' (MECHM) to describe this hybrid mechanism of metal bioaccumulation via intercalation into preformed, biogenic crystals, and note also that MECHM can promote the removal of the transuranic radionuclide neptunium, which is difficult to achieve by conventional methods. 相似文献