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51.
OBJECTIVE: To assess the beliefs of climacteric women regarding their health, menopause, and hormone replacement therapy (HRT). DESIGN: Medical students asked to interview 526 healthy women, ranging from 40 to 64 years of age, between January and February of 2002. Of that number, 26 (4.9%) declined to participate in the interview. Thus, 500 women were interviewed about their beliefs and perceptions regarding their quality of life and health risks, as well as their opinions on menopause and HRT. RESULTS: The mean age of the sample was 53.3 +/- 6.2 years; 83.4% were postmenopausal, and 18.8% were HRT users. Of the women interviewed, 38.6% believed that their health was good. Although 78.8% thought that cancer is the main cause of death, 64% of them considered themselves to be at high risk for cardiovascular disease and osteoporosis. Most (64%) believed that menopause deteriorates the quality of life and that it increases cardiovascular risk (52.4%) and osteoporosis (72.0%). The HRT users perceived that they had better health status (48.9% v 36.2%, P < 0.02) and smaller cardiovascular risk (54.3% v 66.3%, P < 0.04) than did the nonusers; however, they ignored the preventive effect of estrogens in osteoporosis. CONCLUSIONS: Women believe that menopause deteriorates their health. The HRT users perceived themselves to be healthier and to have a smaller risk for cardiovascular disease.  相似文献   
52.
53.
Keratin 19 and nuclear reactivity to an endogenous lectin, galectin-1, represent a potential marker of epidermal stem cells. We detected expression of keratin 19 and nuclear binding sites for galectin-1 in adult cells migrating from the hair follicle, where cells expressing keratin 19 are located in the bulge region. The results were compared with the expression of both markers in cells adhering from suspension prepared from the interfollicular epidermis without keratin-19-positive cells and with nuclear binding sites for galectin-1. The results were compared with data from basal cell carcinomas. All cells were analyzed concerning size, as it is known that cell diameter influences the clonogenic potential of keratinocytes. The major result of this study is the observation of transient expression of keratin 19 and nuclear galectin-1 binding sites in originally negative interfollicular epidermal cells induced by adhesion. These cells were very small in size, similar to basal cells of the interfollicular epidermis or the bulge region of the hair follicle. The influence of the suspension regimen on beta1-integrin expression, cell diameter and growth was also monitored. A population of cells highly positive for beta1 integrin of the same diameter as keratin-19-positive cells insensitive to induction of terminal differentiation by lack of anchorage was characterized. Cells of the same size were also observed in the keratin-19-positive cells of basal cell carcinomas. In conclusion, the expression of poor levels of differentiation induced by cell adhesion is transient. Also, keratin 19 expression should not be exclusively regarded as a marker of stem cell activity.  相似文献   
54.
It has been suggested that polyphenolic substances provide protection against the risk factors of cardiovascular diseases. The present study was designed to investigate whether application of red wine polyphenols influences the kinetic properties of the renal Na+,K(+)-ATPase in rats with hypertension (164 +/- 8 mmHg) that was experimentally induced by the NO synthase inhibitor N(G.) -nitro-L- arginine methyl ester (L-NAME). Polyphenols in a dose of 40 mg kg(-1) day(-1) in drinking fluid induced different effects on the properties of the renal Na+,K(+)-ATPase depending on the mode of their administration. Preventive application of polyphenols during the development of hypertension (144 +/- 5 mmHg) partially protected the Na+,K(+)-ATPase molecule against hypertension-induced deterioration via increased capability of the enzyme to bind ATP and/or Na+ as suggested by decrease of Km and KNa, respectively, even to values lower than in controls. However, polyphenols did not prevent the hypertension-induced reduction of the number of active Na+,K(+)-ATPase molecules as shown by similar V(max) values as compared to the hypertensive L-NAME group. The above protection is probably secured by a NO-dependent mechanism as suggested by 150% increase of the NO synthesis. Additional treatment of already hypertensive animals with polyphenols (153 +/- 8 mmHg) resulted in partial restoration of the Na+,K(+)-ATPase affinities especially for sodium as indicated by significant diminution of KNa. However, polyphenols in this mode of application did not slow down the L-NAME-induced decrease in the number of Na+,K(+)-ATPase molecules in the kidney as suggested by additional significant decrease in V(max) values when comparing this group with the control group and also the hypertensive L-NAME group. In this case the polyphenols affected the Na,K-ATPase molecule in a NO-independent way as indicated by the fact that polyphenols failed to restore normal NO synthesis.  相似文献   
55.
This article is aimed at developing of multimedia teaching programs. Authoring tool Authorware Professional for Windows is briefly described as a suited system for the developing of didactic applications. Author presents own application based on Authorware--Biophysics of perception of sound and light. At the end are also disscused benefits of multimedia teaching tools.  相似文献   
56.
There has been an increasing frequency of deep mycotic infections over the last years complicating mostly disease states with immunosuppression. During the last 30 years, 54 cases of mycotic infection of the heart were identified at the Fingerland Department of Pathology in Hradec Králové, with 32 cases during the last 10 years alone (prevalence 0.2% of 28 199 autopsies). A review of the sex, age, etiology, source of infection, principal disease and morphological cardiac findings is presented. There was male predominance (74%). The mean age of the patients was 48 years (ranging from 15 days to 87 years). Yeasts of genus Candida dominated, followed in incidence by genus Aspergillus. The postmortem haemocultivation was positive in only 25% of all cases, while cultivation from a vegetation or a myocardial abscess was positive in 61%. The probable source of infection was detected in 28 patients; very often it was bronchopneumonia or an infected central venous catheter. Endocarditis was found in 28 cases, including six cases on a prosthetic valve and four cases on mural endocardium. Isolated myocarditis was found in 25 patients. There was also one case of isolated mycotic pericarditis. In more than half of all patients there was a state of immunosuppression, usually caused by a haematologic malignancy.  相似文献   
57.
It is known that beta-amyloid peptide (Abeta) contributes to the neurodegeneration in Alzheimer's disease (AD) and operates through activation of an apoptotic pathway. Apoptotic signal is driven by a family of cysteine proteases called caspases. The beta-amyloid precursor protein (APP) is directly and efficiently cleaved by caspases during apoptosis, resulting in elevated beta-amyloid peptide formation. Cerebellar neurons from rat pups were treated with the aged Abeta(25-35) at 1 and 5 microM and fluorescence assays of caspase activity performed over 4 days. We observed an increase in caspase activity after 48 h treatment in both 1 and 5 microM treated cells, then (72-96 h) caspase activity decreased to control values. The data presented support the hypothesis that Abeta(25-35)-induced apoptosis is mediated by the activation of Caspase-3 and that this is a transient effect.  相似文献   
58.
In order to gain a better insight into the structure and function of the regulatory domain (RD) of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, 19 RD missense mutations that had been identified in patients were functionally characterized. Nine of these (I601F, L610S, A613T, D614G, I618T, L619S, H620P, G628R and L633P) resulted in aberrant processing. No or a very small number of functional CFTR proteins will therefore appear at the cell membrane in cells expressing these mutants. These mutations were clustered in the N- terminal part of the RD, suggesting that this subdomain has a folding pattern that is very sensitive to amino acid changes. Mutations that caused no aberrant processing were further characterized at the electrophysiological level. First, they were studied at the whole cell level in Xenopus laevis oocytes. Mutants that induced a whole cell current that was significantly different from wild-type CFTR were subsequently analysed at the single channel level in COS1 cells transiently expressing the different mutant and wild-type proteins. Three mutant chloride channels, G622D, R792G and E822K CFTR, were characterized by significantly lower intrinsic chloride channel activities compared with wild-type CFTR. Two mutations, H620Q and A800G, resulted in increased intrinsic chloride transport activities. Finally, T665S and E826K CFTR had single channel properties not significantly different from wild-type CFTR.   相似文献   
59.
Previous studies have suggested that corneal stromal keratocytes express the CD34 antigen. We wished to investigate CD34 antigen expression in normal mouse cornea using dual- and triple-staining techniques. Whole-mount preparations of mouse and rat corneas were examined with confocal microscopy using single, dual, or triple immunostaining to study their morphology, phenotype, and distribution. Single-cell suspensions from normal mouse corneas were also prepared and analyzed by flow cytometry. After short-term culture of corneal stromal explants, nonadherent cells were harvested and cytospins were prepared and stained for different markers.Combined staining for F-actin and leukocyte differentiation markers clearly showed that the corneal stroma contains a population of CD45(+) resident bone marrow-derived cells, whereas most cells were CD45-F-actin(+) keratocytes. A significant proportion (two thirds) of CD45(+) cells in the normal corneal stroma expressed CD34(+), whereas no CD45(-) cells (i.e., keratocytes) coexpressed CD34. In addition, CD34(+) cells were CD11c(-) and CD11b(+). Fewer than 10% of the CD34(+) cells also coexpressed Sca-1(+), but no CD34(+) cells coexpressed major histocompatibility complex (MHC) class II(+). In contrast, the remaining population of CD45(+)CD34(-) cells in the corneal stroma expressed CD11b, MHC class II(+) but not CD11c and were found mostly in the anterior and peripheral part of stroma. These cells are in intimate contact with corneal keratocytes, which stained only for F-actin and were negative for all leukocyte markers. Very few CD45(+) cells expressed the B220 marker, suggesting a plasmacytoid dendritic cell phenotype. Flow cytometry analyses confirmed the morphometric data showing that 68% of CD45(+) cells coexpress CD34 and CD11b, whereas 22% are CD11b(+)CD34(-).We conclude that the normal mouse cornea contains two populations of bone marrow-derived leukocytes, both of which are distinct from stromal keratocytes. The larger population resembles CD34(+) hemopoietic stem cells, whereas the smaller population are CD34(-)CD11b(+) MHC class II(+) macrophages. A very small percentage comprises plasmacytoid dendritic cells.  相似文献   
60.
This paper reports the results of a longitudinal study of malaria incidence (1998-2002) among the Pakaanóva (Wari') Indians, Brazilian southwest Amazon region, based on data routinely gathered by Brazilian National Health Foundation outposts network in conjunction with the Indian health service. Malaria is present yearlong in the Pakaanóva. Statistically significant differences between seasons or months were not noticed. A total of 1933 cases of malaria were diagnosed in the Pakaanóva during this period. The P. vivax / P. falciparum ratio was 3.4. P. vivax accounted for 76.5% of the cases. Infections with P. malariae were not recorded. Incidence rates did not differ by sex. Most malaria cases were reported in children < 10 years old (45%). About one fourth of all cases were diagnosed on women 10-40 years old. An entomological survey carried out at two Pakaanóva villages yielded a total of 3.232 specimens of anophelines. Anopheles darlingi predominated (94.4%). Most specimens were captured outdoors and peak activity hours were noted at early evening and just before sunrise. It was observed that Pakaanóva cultural practices may facilitate outdoor exposure of individuals of both sexes and all age groups during peak hours of mosquito activities (e.g., coming to the river early in the morning for bathing or to draw water, fishing, engaging in hunting camps, etc). In a context in which anophelines are ubiquitous and predominantly exophilic, and humans of both sexes and all ages are prone to outdoor activities during peak mosquito activity hours, malaria is likely to remain endemic in the Pakaanóva, thus requiring the development of alternative control strategies that are culturally and ecologically sensitive.  相似文献   
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