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11.
Epidemiology of gentamicin-resistant, gram-negative bacillary colonization in a spinal cord injury unit. 下载免费PDF全文
A prospective epidemiological survey of a spinal cord injury unit for gentamicin-resistant, gram-negative bacilli was undertaken. The initial survey of the unit suggested a low level of cross-infection involving Pseudomonas aeruginosa and Providencia stuartii. However, a longitudinal study of new admissions revealed that only 13 of 52 nosocomial acquisitions could be considered to be due to cross colonization. Comparison of data on antibiotic use did not suggest selective pressure for resistant endogenous flora. Nosocomial acquisition was directly related to the length of the hospital stay. Antibiotic susceptibility testing of gentamicin-resistant, gram-negative bacilli showed only minor differences between nosocomial isolates and those present during the initial survey. Of the usual antimicrobial agents, amikacin, carbenicillin, and cefoxitin were the most active against all organisms, with the exception of Serratia spp. Of the new beta-lactams, ceftazidime and imipemide (N-formimidoyl thienamycin) were most active. 相似文献
12.
Willis F Graff-Radford N Pinto M Lawson L Adamson J Epstein D Parfitt F Hutton M O'Brien PC 《Journal of the National Medical Association》2003,95(1):71-76
Through its role in lipid metabolism, Apolipoprotein epsilon4 (ApoE4) may affect "brain repair" in stroke, brain hemorrhage, Alzheimer's disease, and other brain injury syndromes for which African Americans may have greater morbidity and mortality. Cross-cultural evaluations of these and other genetic factors may provide insight on possible ethnic differences in risk of morbidity to acute central nervous system (CNS) injury and chronic neurodegenerative processes. As an initial step toward expanding knowledge of ApoE allele frequencies for persons of African descent, we compared ApoE genotype of a group of 70 young Ugandans to 59 (subset of a larger group of 342 African Americans of all ages) age-matched African Americans and to published frequencies for Caucasians and Asians. We found that the ApoE4 and epsilon2 alleles are more frequent in Ugandans (U) than Caucasians (C) or Asians (A) with corresponding alleles showing significant elevations of epsilon2 (U 15.71%, C 8.40%, A 4.20%) and 14 (U 25%, C 13.70%, A 8.90%) (p < .001). Comparing the differences between Ugandans and age-appropriate African Americans (AA) was not statically significant, but this outcome may be due to small sample size. These results provide the only published ApoE frequencies for Ugandans and the complete set of data provides the largest published community group of ApoE frequencies for African Americans. 相似文献
13.
Dithiothreitol prevents age-associated decrease in oocyte/conceptus viability in vitro 总被引:2,自引:0,他引:2
The present study was designed to ascertain whether the negative effects on
reproductive potential of post-ovulatory ageing in vitro of oocytes can be
prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were
aged in vitro for 12 h prior to insemination in the presence of varying
concentrations of L-ascorbic acid, 6-methoxy-
2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine
dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta-
mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was
associated with lower fertilization rate, higher proportion of concepti
exhibiting cellular fragmentation at 24 h post-insemination and lower
percentage of concepti reaching the blastocyst stage. Ascorbic acid, Trolox
and EDTA had no effect on cellular fragmentation or potential of oocytes
for development. However, the probability of an oocyte reaching the
blastocyst stage was decreased (P < or = or = 0.05) in oocytes incubated
in the presence of L-cystine (50 and 500 microM) and beta-mercaptoethanol
(5, 50 and 500 microM) when compared to control aged oocytes.
Age-associated cellular fragmentation at 24 h post-insemination was
partially prevented (P < or = 0.05) by incubating oocytes in the
presence of beta-mercaptoethanol (500 microM). DTT (50 and 500 microM)
increased (P < or = 0.05) fertilization rate and number of cells at 81 h
post-insemination to levels similar to those exhibited by control oocytes.
Furthermore, both age-associated fragmentation at 24 h post-insemination (P
< or = 0.05) and decreased potential of oocytes for development to the
blastocyst stage (P < or = 0.05) were prevented, at least in part, by
culturing oocytes in the presence of DTT (50 microM). Although the
mechanism by which DTT exerts its beneficial effects on aged oocytes
remains to be elucidated, it may protect oocytes by preventing oxidation of
free thiol groups and/or altering a redox-independent signalling pathway
that mediates cellular fragmentation and death.
相似文献
14.
Determination of the parent of origin in nine cases of prenatally detected chromosome aberrations found after intracytoplasmic sperm injection 总被引:1,自引:17,他引:1
Van Opstal D; Los FJ; Ramlakhan S; Van Hemel JO; Van Den Ouweland AM; Brandenburg H; Pieters MH; Verhoeff A; Vermeer MC; Dhont M; In't Veld PA 《Human reproduction (Oxford, England)》1997,12(4):682-686
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic
sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome
aberrations including two cases of 47,XXY, four cases involving a 45,X cell
line and three autosomal trisomies. Molecular analysis of the parental
origin of the deleted or supernumerary chromosome was performed by using
polymorphic microsatellite markers. Six cases involving a sex chromosome
abnormality were found to be of paternal origin while the two trisomic
cases that could be analysed were of maternal origin. Two cases involved
the same infertile couple who had two consecutive ICSI pregnancies
terminated because of a chromosome abnormality. The replaced embryos in
both cases originated from a single batch of ICSI fertilized oocytes of
which part was used to initiate the first pregnancy and part was
cryopreserved and used to initiate the second pregnancy.
相似文献
15.
16.
Floyd Thompson Julia Emerson William Dalton Jin-Ming Yang Daniel McGee Hugo Villar Sally Knox Kathy Massey Ronald Weinstein Achyut Bhattacharyya Jeffrey Trent 《Genes, chromosomes & cancer》1993,7(4):185-193
Cytogenetic analysis was performed on a selected series of short-term cultures of primary breast carcinomas from 28 patients. All patients had histopathologically confirmed malignancies, with the majority (25/28 cases) demonstrating infiltrating ductal carcinoma. All 28 cases evidenced clonal chromosome abnormalities, with 10/28 displaying only numeric aberrations, whereas 18/28 displayed clonal structural alterations. In near-diploid tumors the most common numeric changes were — 17 and — 19. However, trisomy 7 was the only numeric change in two near-diploid tumors. Structural chromosome alterations were primarily isochromosomes, apparent terminal deletions, and unbalanced non-reciprocal translocations. Chromosomes 1 (10/18–56%) and 6 (8/18–44%) were most frequently altered in this series. Breakpoints of clonal structural abnormalities were shown to cluster to several chromosome segments, including 1p22-q11, 3p11, 6p11–13, 7p11-q11, 8p11-q11, and 19q13. Analysis of the gain or loss of specific chromosome segments revealed that the most consistent tendency was over-representation of 1q, 3q, and 6p. © 1993 Wiley-Liss, Inc. 相似文献
17.
Sid E O'Bryant John A Lucas Floyd B Willis Glenn E Smith Neill R Graff-Radford Robert J Ivnik 《Archives of clinical neuropsychology》2007,22(3):327-332
The influence of education on cognition has received a great deal of attention in the literature. Although there is general consensus regarding the importance of education on cognitive functioning, the extent to which self-reported level of education corresponds to true educational attainment remains unclear, especially in ethnic minority populations where equal access to education has not always been available. Several investigators have suggested that reading skill may serve as a quantitative estimate of true education experience. Among African-Americans, however, research has shown that self-reported educational level consistently over predicts estimated reading level. The current study analyzed the discrepancy between self-reported years of education completed and estimated reading level in a sample of community-dwelling, elderly African-Americans participating in Mayo's Older African Americans Normative Studies (MOAANS) (Lucas, J.A., Ivnik, R.J., Willis, F.B., Ferman, T.J., Smith, G.E., Parfitt, F.C., Petersen, R.C., & Graff-Radford, N.R. (2005). Mayo's Older African Americans Normative Studies: Normative data for commonly used clinical neuropsychological measures. The Clinical Neuropsychologist, 19, 162-183). In this sample, 29% of the participants read at a level that was 3 or more years below what would be expected based on self-report of education attained. This study also sought to evaluate the extent to which this discrepancy fluctuated as a function of demographic variables such as location of schooling (urban, suburban, rural; North vs. South), parental education and literacy, and percentage of segregation in schooling. Implications of these results are discussed, as are areas for further inquiry. 相似文献
18.
A woman with neurofibromatosis (von Recklinghausen's disease) presented with a giant plexiform neuroma of the arm and chest wall, with dysplastic scoliosis and a pseudarthrosis of the humerus. Her arm resembled that of the "Elephant Man" described by Sir Frederick Treves. 相似文献
19.
James Kortney Floyd Aycock Dawn M. Fouquier Kate Hires Kimberly A. Barkin Jennifer L. 《Maternal and child health journal》2022,26(4):788-795
Maternal and Child Health Journal - Racial identity, which is the degree that individuals define themselves regarding their racial group membership, may influence the mental well-being of Black... 相似文献
20.
Flaherty JD Levett PN Dewhirst FE Troe TE Warren JR Johnson S 《Journal of clinical microbiology》2003,41(5):2237-2239
This is the first reported case of endocarditis due to the Lactobacillus-like vancomycin-resistant gram-positive bacillus Weissella confusa. Full identification and susceptibility testing of Lactobacillus-like organisms recovered in blood culture should be performed for patients with clinical presentations that suggest endocarditis. 相似文献