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51.
Lymphocyte transformation to 1-24ACTH, as assessed by the incorporation of tritiated thymidine, has been demonstrated to be associated with severe adverse reactions occurring in patients receiving a Zn-linked 1-24ACTH preparation (Tetra cosactrin depot, 'Synacthen'). Antibodies measured with an isotope-binding assay occurred commonly in all patients receiving therapy and did not correlate with adverse reactions. Lymphocyte transformation with the 1-24ACTH polypeptide, a part of the naturally occurring ACTH molecule, has not been previously recorded. The significance of antibodies and cell-mediated immunity to this polypeptide hormone is discussed. 相似文献
52.
Assessment of the epidemic potential of a new strain of rotavirus associated with the novel G9 serotype which caused an outbreak in the United States for the first time in the 1995-1996 season
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Clark HF Lawley DA Schaffer A Patacsil JM Marcello AE Glass RI Jain V Gentsch J 《Journal of clinical microbiology》2004,42(4):1434-1438
Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community. 相似文献
53.
54.
A study of the degree of progesterone support required for the maintenance
of various stages of pregnancy was undertaken in mice. Mated females were
ovariectomized at various stages of pregnancy and progesterone and
oestradiol support provided by s.c. Silastic implants with known release
characteristics. In the earliest stages of pregnancy (days 1-5), very low
concentrations of progesterone (<25% of normal physiological values)
were sufficient to maintain pre-implantation stages and allow implantation.
In the immediate post-implantation period (days 5-9), the development of
implantation sites and decidualization required considerably higher
progesterone support. In mid-pregnancy (days 11-14), progesterone alone
could not maintain pregnancy unless present in very high amounts; however,
the presence of oestradiol during this period lowered the progesterone
requirements to well within the physiological range. This effect of
oestradiol started on day 11 but required the level of oestradiol support
to be kept within strictly defined limits, with high concentrations
inducing abortion. Progesterone alone was able to maintain pregnancy from
day 15. These results indicate that the minimal progesterone support
required for pregnancy in mice varies considerably at different stages of
pregnancy and is at least partly modulated by oestradiol.
相似文献
55.
Comparison of the hybrid capture tube test and PCR for detection of human papillomavirus DNA in cervical specimens. 总被引:5,自引:3,他引:5
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J U Cope A Hildesheim M H Schiffman M M Manos A T Lrincz R D Burk A G Glass C Greer J Buckland K Helgesen D R Scott M E Sherman R J Kurman K L Liaw 《Journal of clinical microbiology》1997,35(9):2262-2265
The strong association of human papillomavirus (HPV) and cervical cancer makes it important to study HPV detection methods that may play a role in cervical cancer screening. We compared two DNA methods that are commonly used for HPV research in the United States: the MY09/MY11 L1 consensus primer PCR-based test and the first-generation Hybrid Capture tube method (HCT). Laboratory assays by each method were performed with 596 cervicovaginal specimens collected from participants in a large cohort study conducted in Portland, Oreg. Included were 499 specimens from women whose cytology was normal and 97 specimens from women with squamous intraepithelial lesions (SILs). The overall HPV DNA positivity for known types was 22.5% by PCR compared to 13.6% by HCT. When the analysis was restricted to the 14 HPV types detectable by both methods, the sensitivity of HCT, with PCR used as the standard for HPV status, was higher for specimens from women with concurrent SILs (81.0%) than for specimens from women with normal cytology (46.7%). Among specimens testing positive by both methods, 97.2% of the time the two methods agreed on whether specimens were positive for cancer-associated HPV types. Both of these HPV test methods provide information that supplements the information provided by the Pap smear. The PCR method has higher analytic sensitivity than HCT in detecting HPV, but HCT may be helpful in identifying women with concurrent SILs. 相似文献
56.
J L Cromien C A Himmelreich R I Glass G A Storch 《Journal of clinical microbiology》1987,25(12):2359-2362
We evaluated a new commercial enzyme immunoassay (EIA) for rotavirus (Rotavirus EIA; International Diagnostic Laboratories, Chesterfield, Mo.). A total of 161 consecutive stool samples (including 18 from infants less than 30 days old) submitted to the diagnostic laboratory at Children's Hospital, Washington University Medical Center, St. Louis, Mo., for rotavirus detection were tested by Rotavirus EIA and by Rotazyme II (Abbott Laboratories, North Chicago, III.) according to the instructions of the manufacturer. In addition, 16 samples from infants less than 30 days old without diarrhea were tested by both assays. Samples showing discrepant results after repeat testing were examined by electron microscopy. Nine samples yielding discrepant results were also tested by using a reference EIA directly on the specimen and on culture supernatants from two passages in MA 104 cells. Rotavirus EIA and Rotazyme II yielded concordant results for 85% of the samples. All of the 26 discrepant samples tested negative by Rotavirus EIA and positive (15 samples) or equivocal (11 samples) by Rotazyme II. These samples included 11 from symptomatic infants more than 30 days old, 2 from symptomatic infants less than 30 days old (neonates), and 2 from neonates without diarrhea. Rotavirus was not detected in any of the 24 that were examined by electron microscopy or in any of the 9 that were tested by the reference EIA. The sensitivity, specificity, positive predictive value, and negative predictive value were 100% for Rotazyme EIA and 100, 90, 70, and 100%, respectively, for Rotazyme II. Rotavirus EIA was comparable to Rotazyme II in ease of performance. We conclude that Rotavirus EIA is equally sensitive and more specific than Rotazyme II for detecting rotavirus. Rotavirus EIA is a practical and accurate rotavirus assay for use in clinical laboratories. 相似文献
57.
Use of 16S rRNA gene sequencing for rapid identification and differentiation of Burkholderia pseudomallei and B. mallei
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Gee JE Sacchi CT Glass MB De BK Weyant RS Levett PN Whitney AM Hoffmaster AR Popovic T 《Journal of clinical microbiology》2003,41(10):4647-4654
Burkholderia pseudomallei and B. mallei, the causative agents of melioidosis and glanders, respectively, are designated category B biothreat agents. Current methods for identifying these organisms rely on their phenotypic characteristics and an extensive set of biochemical reactions. We evaluated the use of 16S rRNA gene sequencing to rapidly identify these two species and differentiate them from each other as well as from closely related species and genera such as Pandoraea spp., Ralstonia spp., Burkholderia gladioli, Burkholderia cepacia, Burkholderia thailandensis, and Pseudomonas aeruginosa. We sequenced the 1.5-kb 16S rRNA gene of 56 B. pseudomallei and 23 B. mallei isolates selected to represent a wide range of temporal, geographic, and origin diversity. Among all 79 isolates, a total of 11 16S types were found based on eight positions of difference. Nine 16S types were identified in B. pseudomallei isolates based on six positions of difference, with differences ranging from 0.5 to 1.5 bp. Twenty-two of 23 B. mallei isolates showed 16S rRNA gene sequence identity and were designated 16S type 10, whereas the remaining isolate was designated type 11. This report provides a basis for rapidly identifying and differentiating B. pseudomallei and B. mallei by molecular methods. 相似文献
58.
Rotavirus diarrhea in Bangladeshi children: correlation of disease severity with serotypes. 总被引:7,自引:0,他引:7
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C Bern L Unicomb J R Gentsch N Banul M Yunus R B Sack R I Glass 《Journal of clinical microbiology》1992,30(12):3234-3238
To improve the understanding of the relative importance of serotypes of rotavirus in dehydrating diarrhea, we examined the correlation of clinical characteristics and disease severity with serotype in 2,441 diarrheal episodes among children younger than 2 years of age in rural Bangladesh. Of 764 rotavirus-associated episodes, a single G type (serotype 1, 2, 3, or 4) was determined by oligonucleotide probe in 485 (63%), while 233 episodes were nontypeable. Episodes with G types 2 and 3 were associated with more-severe dehydration than episodes associated with G type 1 or 4 or with nontypeable rotavirus. Episodes did not differ by G type in prevalence of vomiting, copious diarrhea, fever, abdominal pain, or length of treatment center stay. Rotavirus reinfections were detected in seven children, with homologous reinfection (G type 2) in one. Twelve children with diarrhea who died had rotavirus detected in stool specimens within 30 days of death. Children who died were more likely to be malnourished than were surviving children with rotavirus diarrhea. Of 40 specimens tested by polymerase chain reaction, 29 (72.5%) were P type 1, 9 (22.5%) were P type 2, 1 (2.5%) was P type 3, and 1 (2.5%) was nontypeable. One severely symptomatic diarrheal episode was associated with P type 3 rotavirus, a serotype usually found in asymptomatic nursery infections. Although G types 2 and 3 were associated with more-severe dehydration than other serotypes, the differences do not appear to be of major clinical importance. Effective vaccines should protect against all four major G types. 相似文献
59.
Comparison of Southern blot hybridization and polymerase chain reaction methods for the detection of human papillomavirus DNA. 总被引:8,自引:2,他引:8
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M H Schiffman H M Bauer A T Lorincz M M Manos J C Byrne A G Glass D M Cadell P M Howley 《Journal of clinical microbiology》1991,29(3):573-577
A methodologic study was performed to compare the polymerase chain reaction (PCR) and Southern blot hybridization, two commonly used testing strategies for the detection of human papillomavirus (HPV) infection. Three laboratories tested masked aliquots of exfoliated cervical cell specimens obtained from 120 women by cervicovaginal lavage. The study population included 32 women with condylomatous atypia or cervical intraepithelial neoplasia and 88 control women with no known history of cervical neoplasia. Two laboratories used PCR with different sets of consensus primers for HPV detection. The third laboratory used low-stringency Southern blot hybridization to identify all HPV types, followed by high-stringency Southern and/or dot blot hybridization to confirm specific HPV types. One of the PCR primer sets detected HPV types with a differential efficiency that was not predicted by analysis of DNA sequences or direct testing of HPV-containing plasmids. In contrast, the second PCR primer set was shown to be a much broader consensus system, detecting the same HPV types as Southern blotting, though requiring much less clinical specimen. Over 80% of women with cervical intraepithelial neoplasia or condylomatous atypia were found to be HPV infected both by Southern blotting and by the second PCR primer set. Among the control women, 11% were HPV positive by Southern blotting, while 31% were positive with the second set of primers. Most of the HPV infections found only by PCR were not due to HPV type 6, 11, 16, 18, 31, 33, or 45. These known HPV types were uncommon among normal women in the study population, even as determined by the PCR method. 相似文献
60.
The terminal nucleotide sequences of group C Cowden rotavirus gene segments 1-4 were determined. When compared with the published sequences, we found 14 to 29 additional nt at the 5 ends of the four reported gene sequences. For the 3 ends, we observed an additional 16 nt in gene 2 and 14 fewer nt in gene 4. 相似文献