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91.
The full extent of the polymorphism of ELA-DRA in Equidae is not yet known. Given the apparent differences in DRA polymorphisms between Equidae and other species, the aims of this study were to more fully characterize ELA-DRA, determine the extent of gene polymorphism and establish the allele-frequency distribution. An allele reference panel for the second exon of ELA-DRA was established by sequence-based typing of 69 equine DNA samples consisting of various breeds of domestic horse (Equus caballus), together with donkeys (Equus asinus), Grant's zebras (Equus boehmi) and one onager (Equus hemionus). Five of the six previously reported alleles detected using single-strand conformation polymorphism were found: ELA-DRA*0101, ELA-DRA*0201, ELA-DRA*0301, ELA-DRA*0501 (Albright-Fraser DG et al. Polymorphism of DRA among equids. Immunogenetics 1996: 43: 315-7) and ELA-DRA*0601 (GenBank accession number AF5419361). In addition to the previously reported alleles, five novel ELA-DRA alleles were detected within the ELA-DRA allele reference panel. One of these was identified in E. caballus (ELA-DRA*JBH11), one in E. boehmi and E. hemionus (ELA-DRA*JBZ185) and three in E. asinus (ELA-DRA*JBD3, ELA-DRA*JBD17 and ELA-DRA*JBH45). A total of 565 equine DNA samples were screened using reference-strand-mediated conformation analysis, a double-stranded conformation-based mutation detection system that can be used to type existing ELA-DRA alleles and identify new variants. Based on our findings, at least 11 ELA-DRA alleles are now known to exist, and this level of polymorphism at the DRA locus appears to be unique to the genus Equus. Both the previously reported alleles and the new alleles displayed a species-specific distribution.  相似文献   
92.
We tested serial bone-marrow samples from 47 adults with acute myeloblastic leukemia in remission for reactivity with heteroantiserums to leukemia-associated antigens, to determine whether imminent relapse could be detected in patients with acute leukemia. Of 26 patients who relapsed by standard morphologic criteria, 21 had increased immunoreactivity of bone marrow for one to six months (mean, 3.7 months) before relapse. High concordance was observed between a positive test and relapse during the period of study (chi-square = 27.53, P less than 0.001). The median time to relapse after a positive test was four months, as compared with the median remission duration of 19 months for the whole group (P less than 0.02, Peto's log-rank analysis). Serologic detection of leukemia-associated antigens in marrow may be a reliable indicator of imminent relapse in acute myeloblastic leukemia.  相似文献   
93.
We examined white-footed mice (Peromyscus leucopus) from Minnesota for infection with the etiologic agent of human granulocytic ehrlichiosis (HGE). From April to September 1997, we collected P. leucopus from Washington County, Minnesota, an area enzootic for HGE. Blood was cultivated in HL60 cells for isolation of the HGE agent. Of 59 mice examined, only a single mouse was culture positive for the HGE agent. The 16S ribosomal DNA sequence of the isolate was determined to be identical to that of the HGE agent. The isolate was reactive with monoclonal antibodies to the 44-kDa antigen of the HGE agent and was infectious for laboratory mice.  相似文献   
94.
Lymphokine production by human milk lymphocytes.   总被引:3,自引:1,他引:3       下载免费PDF全文
To assess the functional capability of human milk lymphocytes, we studied phytohemagglutinin-induced lymphokine production by breast milk and, for comparison, peripheral blood lymphocyte cultures. Two lymphokines, lymphocyte-derived chemotactic factor (LDCF) and immune interferon, were assayed in supernatants of milk and blood lymphocyte cultures obtained from women 2 to 6 days postpartum. Eleven parallel milk and blood samples were studied for LDCF production. In nine experiments, both milk and blood lymphocytes produced LDCF. In the two other experiments, milk cells did not produce LDCF. In 10 milk cultures studied, all produced interferon activity. Acid and heat lability characteristics were typical of immune interferon. These results further characterize milk lymphocytes as immunologically competent and possibly important effector cells in neonatal immunity.  相似文献   
95.
Pastore LM  Carter RA  Hulka BS  Wells E 《Maturitas》2004,49(4):292-303
OBJECTIVE: To examine the prevalence and correlates of self-reported urogenital symptoms (dryness, irritation or itching, discharge, dysuria) among postmenopausal women aged 50-79. DESIGN: A cross-sectional analysis based on n=98,705 women enrolled in the US-based Women's Health Initiative observational study and clinical trials. Urogenital symptoms, symptom severity (mild, moderate, severe), and all covariates were self-reported through questionnaires at enrollment. Prevalence rates of each urogenital symptom were examined and logistic regression was used to identify potential correlates. RESULTS: Prevalence rates for each symptom were: dryness, 27.0%; irritation or itching, 18.6%; discharge, 11.1%; and dysuria, 5.2%. Four factors were correlated with two or more symptoms: Hispanic ethnicity (adjusted odds ratio (AOR)=2.1-3.1 versus white women across all symptoms), obesity (AOR=2.2 severe discharge versus none, AOR=3.6 severe irritation/itching versus none), treated diabetes (pills or shots) compared to no diabetes (AOR=2.4 severe dysuria versus none, AOR=3.2 severe irritation/itching versus none), and vaginal cream HRT/ERT compared to those who never used HRT/ERT (AOR=4.4 severe dryness versus none, AOR=4.6 severe irritation/itching versus none). Factors not associated with the symptoms included sexual activity, age, years since menopause, current smoking, marital status, gravidity, and natural versus surgical menopause. CONCLUSIONS: This is the first report to document urogenital symptoms by race/ethnicity among an exclusively postmenopausal population. We found an elevated prevalence of urogenital symptoms among women who are Hispanic, obese, and/or diabetic. Confirmation of our findings in these subgroups, and, if confirmed, analysis on why these populations are at greater risk, are areas for future research.  相似文献   
96.
Development of an effective vaccine against Leishmania infection is a priority of tropical disease research. We have recently demonstrated protection against Leishmania major in the murine and nonhuman primate models with individual or combinations of purified leishmanial recombinant antigens delivered as plasmid DNA constructs or formulated with recombinant interleukin-12 (IL-12) as adjuvant. In the present study, we immunized BALB/c mice with a recombinant polyprotein comprising a tandem fusion of the leishmanial antigens thiol-specific antioxidant, L. major stress-inducible protein 1 (LmSTI1), and Leishmania elongation initiation factor (LeIF) delivered with adjuvants suitable for human use. Aspects of the safety, immunogenicity, and vaccine efficacy of formulations with each individual component, as well as the polyprotein referred to as Leish-111f, were assessed by using the L. major challenge model with BALB/c mice. No adverse reactions were observed when three subcutaneous injections of the Leish-111f polyprotein formulated with either MPL-squalene (SE) or Ribi 529-SE were given to BALB/c mice. A predominant Th1 immune response characterized by in vitro lymphocyte proliferation, gamma interferon production, and immunoglobulin G2A antibodies was observed with little, if any, IL-4. Moreover, Leish-111f formulated with MPL-SE conferred immunity to leishmaniasis for at least 3 months. These data demonstrate success at designing and developing a prophylactic leishmaniasis vaccine that proved effective in a preclinical model using multiple leishmanial antigens produced as a single protein delivered with a powerful Th1 adjuvant suitable for human use.  相似文献   
97.
98.
Curvularia infections in humans are relatively uncommon despite the ubiquitous presence of this soil-dwelling dematiaceous fungus in the environment. Originally thought to be solely a pathogen of plants, Curvularia has been described as a pathogen of humans and animals in the last half-century, causing respiratory tract, cutaneous, and corneal infections. Only three previous cases of central nervous system involvement by Curvularia have been documented in the medical literature. We report a fatal case of cerebral Curvularia infection in which there was no known history of immunocompromise or prior respiratory tract or sinus infection in the patient.  相似文献   
99.
A family study of hydrocephalus resulting from aqueduct stenosis.   总被引:3,自引:1,他引:3       下载免费PDF全文
Stenosis of the aqueduct of Sylvius accounts for about one third of cases of congenital hydrocephalus. At least 32 families have been reported in which the aqueduct stenosis is inherited in an X linked fashion. In half of these families, flexed adducted thumbs were noted in some affected family members. Occasionally other male members were mentally retarded, suggesting limited expression of the gene. The problem of giving genetic advice to an isolated, clinically unremarkable, case of aqueduct stenosis remains, so a family study was undertaken based on 24 such cases seen at The Hospital for Sick Children over a 19-year period. There were 15 male and nine female index patients. The diagnosis was confirmed in all cases by air encephalogram. One boy had a radial club hand and another developed clasped thumbs secondary to spasticity. No cases had hyaloidoretinal dysplasia. The 15 boys had 18 brothers and 19 sisters, of whom one sister was similarly affected. The nine girls had 12 sibs, none of whom was affected. This study, combined with a similar study in the USA, suggests that the empirical risk of recurrence of a sporadic case of aqueduct stenosis is about 4.5%.  相似文献   
100.
A new route for the synthesis of high glass transition temperature, thermally stable polymer foams has been developed, using compositionally asymmetric microphase-separated block copolymers where the minor component (poly(propylene oxide)) is thermally labile and the major component (polyimide) is thermally stable. The minor component decomposes to low molecular weight species upon heating, and the decomposition products diffuse out of the film, leaving behind pores embedded in a matrix of the thermally stable component. In this study, the polyimide block was crosslinked with ethynyl functionalities to obtain a stable porous structure. The decomposition of the propylene oxide in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild conditions were required to avoid rapid depolymerization of the propylene oxide and plasticization of the polyimide matrix. The foams showed pore sizes with diameters up to a micrometer in size as well as the expected reduction in the mass density.  相似文献   
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