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21.
Jacobo E. Mintzer M.D. Mark P. Rubert Ph.D. David Loewenstein Ph.D. Edgardo Gamez M.D. Agustin Millor L.C.S.W. Rocio Quinteros M.S. Linda Flores M.D. Meridith Miller R.N. Ph.D. Adrianne Rainerman Carl Eisdorfer Ph.D. M.D. 《Community mental health journal》1992,28(4):293-303
This study assessed Cuban-American Hispanic and White non-Hispanic daughters who were major caregivers for their mothers suffering from Alzheimer's Disease. Although patients in both ethnic groups did not differ in their level of cognitive and functional impairment, Cuban-American Hispanic patients were significantly more likely to be living in their daughters' homes while the White non-Hispanic patients resided in institutional settings. Caregivers were equivalent in their knowledge and utilization of community services, but Cuban-American daughters were significantly more aware of financial aid resources. Cuban-American patients were significantly more depressed than their White non-Hispanic counterparts with daughters showing similar but nonsignificant trends. The impact of cultural factors on caregiving is discussed. 相似文献
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Erik Diaz Teresa Gonzlez-Cossío Juan Rivera Maarten D. C. Immink Ruben Dario Mendoza C. Rafael Flores 《American journal of human biology》1991,3(5):525-530
This study aims at assessing the accuracy of estimates of body composition provided by bioimpedance (BIA) equations developed for U.S. populations when applied to a sample of Guatemalan farmers. If these equations were shown to have low validity, the second objective was to develop more accurate estimates of fat-free mass (FFM). One hundred males and females 19 to 45 years of age were randomly selected from four rural communities in the Western Highlands of Guatemala. Bioimpedance equations explained 59 and 33% of the variation in FFM, with a RMSE of 2.7 and 2.8 kg in males and females, respectively. Body fat (BF) predictions had a lower R2. Using the “all possible regressions” procedure, the best subset for prediction of FFM used anthropometric and BIA variables as predictors. The best model for men and women included only anthropometric variables: 75% of the variance in FFM for men and 70% of the variance in women was explained by this model. The RMSE was 2.1 and 1.9 kg for both groups, respectively. It is concluded that FFM can be estimated from anthropometric dimensions with a high degree of accuracy and use of BIA does not provide more valid estimates. 相似文献
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Impaired hair follicle morphogenesis and cycling with abnormal epidermal differentiation in nackt mice,a cathepsin L-deficient mutation 总被引:1,自引:0,他引:1
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Benavides F Starost MF Flores M Gimenez-Conti IB Guénet JL Conti CJ 《The American journal of pathology》2002,161(2):693-703
We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4(+) T-cell deficiency. Also, we recently reported that nkt (now Ctsl(nkt)) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4(+) T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the old furless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctsl(nkt)/Ctsl(nkt) mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2-/- Ctsl(nkt)/Ctsl(nkt) double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation. 相似文献
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Genetic analysis of a human rotavirus that belongs to subgroup I but has an RNA pattern typical of subgroup II human rotaviruses. 总被引:6,自引:13,他引:6
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O Nakagomi T Nakagomi Y Hoshino J Flores A Z Kapikian 《Journal of clinical microbiology》1987,25(7):1159-1164
We have previously found (O. Nakagomi, T. Nakagomi, H. Oyamada, and T. Suto, J. Med. Virol. 17:29-34, 1985), during an epidemiological study in Japan, a novel human rotavirus that belongs to subgroup I but has a long RNA pattern typical of subgroup II human rotaviruses. From the stool specimen containing this virus, we successfully isolated in MA104 cells a rotavirus, designated AU-1, which possesses these novel characteristics. The possibility that strain AU-1 was a laboratory contaminant of an animal rotavirus previously adapted to tissue culture cells was ruled out, and the identity of the AU-1 strain was established. Genetic analysis by RNA-RNA hybridization revealed that the AU-1 strain is not a simple reassortant between subgroup I and II human rotaviruses but that it shares a high level of sequence homology only with the gene encoding VP7 (the major neutralization protein) of serotype 3 human rotaviruses. Weak homology of the genomic RNA segments was also observed between the AU-1 strain and animal rotavirus strains, including rhesus rotavirus strain RRV and bovine rotavirus strain NCDV. These results suggest that the AU-1 strain may be an animal rotavirus that infected a human. 相似文献
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Molecular species of R-protein antigens produced by clinical isolates of group B streptococci. 总被引:8,自引:2,他引:8
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Clinical isolates of group B streptococci from body fluids and mucosal surfaces were examined for production of a trypsin-resistant antigen known as R protein. R protein was extracted with 1% trypsin from cells grown in a semidefined medium. The extracts were tested by immunodiffusion in agarose with a panel of antisera for detection and precise identification of the four species of R protein described by Wilkinson. R antigen was present in 49 of 131 (37%) of the strains tested. Analysis by serotype revealed that 0 of 2 type Ia, 0 of 11 Ib, 1 of 16 (6%) Ia/c, 12 of 15 (80%) II, 0 of 20 II/c, 35 of 49 (71%) III, 0 of 6 IV, and 1 of 12 (8%) nontypeable strains produced R antigen. Production of the R protein and the trypsin-resistant or alpha component of the c protein appeared to be mutually exclusive. R antigen was more prevalent in isolates from blood (50%) than in those from mucosal sites (27%) for type II strains; no difference was seen for type III strains from these sites. Concordant results were obtained with five paired body fluid-mucosal surface isolates from individual patients and with isolates from 17 mother-baby pairs. The most frequent species of R antigen was R4 (45 of 49), followed by R1 (4 of 49). These two species of R protein were biochemically (trypsin resistant and pepsin sensitive) and immunologically identical to the R-protein antigens produced by prototype strains of groups A, B, and C streptococci. 相似文献