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41.
J K Nayar J W Knight P E Kaiser J A Seawright S K Narang 《Journal of the American Mosquito Control Association》1992,8(1):61-64
Susceptibilities of natural populations of sibling species A, B and C of the Anopheles quadrimaculatus complex and the colonized strain A to subperiodic Brugia malayi and Brugia pahangi were compared. All 3 sibling species showed varying degrees of susceptibility to both B. pahangi and B. malayi, and they were considerably more susceptible to B. pahangi than to B. malayi. The rate and intensity of infection to B. pahangi were highest for species A (66.2% and 7.4 L3/female, respectively) and lowest for species B (21.3% and 1.7 L3/female). For B. malayi these values were higher for species A (29.7% and 1.84 L3/female) than for species B (13.3% and 0.86 L3/female) and C (12.6% and 0.75 L3/female). The colonized strain A of An. quadrimaculatus was significantly more susceptible to both Brugia species than the natural populations of sibling species A, B and C. 相似文献
42.
M C Hirst S J Knight M V Bell M Super K E Davies 《Clinical science (London, England : 1979)》1992,83(3):255-264
An amplification of a highly unstable DNA element has been identified at the fragile X locus in Xq27.3. This sequence appears to be both the source of the primary mutation causing the fragile X syndrome, apparently having its causative effect through the methylation of the FMR-1 HTF island and the region of cytogenetic fragility. The direct analysis of the genotype of carrier and affected individuals can be used as a direct diagnosis tool which will improve both the accuracy and speed of diagnosis. The identification of hereditary unstable DNA in a disease with such a wide level of non-penetrance and variable phenotype may give clues as to the basis of non-penetrance in other human genetic disorders. 相似文献
43.
ABSTRACT: Background: The percentage of United States’ births delivered by cesarean section has increased rapidly in recent years, even for women considered to be at low risk for a cesarean section. The purpose of this paper is to examine infant and neonatal mortality risks associated with primary cesarean section compared with vaginal delivery for singleton full‐term (37–41 weeks’ gestation) women with no indicated medical risks or complications. Methods: National linked birth and infant death data for the 1998–2001 birth cohorts (5,762,037 live births and 11,897 infant deaths) were analyzed to assess the risk of infant and neonatal mortality for women with no indicated risk by method of delivery and cause of death. Multivariable logistic regression was used to model neonatal survival probabilities as a function of delivery method, and sociodemographic and medical risk factors. Results: Neonatal mortality rates were higher among infants delivered by cesarean section (1.77 per 1,000 live births) than for those delivered vaginally (0.62). The magnitude of this difference was reduced only moderately on statistical adjustment for demographic and medical factors, and when deaths due to congenital malformations and events with Apgar scores less than 4 were excluded. The cesarean/vaginal mortality differential was widespread, and not confined to a few causes of death. Conclusions: Understanding the causes of these differentials is important, given the rapid growth in the number of primary cesareans without a reported medical indication. (BIRTH 33:3 September 2006) 相似文献
44.
45.
W. M. Gregory P. Smith M. A. Richards C. J. Twelves R. K. Knight R. D. Rubens 《British journal of cancer》1993,68(5):988-995
The outcome for 758 consecutive patients who had received one or more chemotherapy regimens for recurrent or metastatic breast cancer is presented. The response rate following first line treatment was 34%. Median duration of response was 7.8 months, median time to progression was 3.7 months and median survival was 7.9 months. The only factor predicting for response, of factors recorded at presentation and at initiation of chemotherapy, was the use of anthracycline based regimens, though this may reflect the patient selection policy. Initial disease free interval, presence of liver metastases and use of anthracyclines were significantly related to time to progression. Several factors related to survival following first chemotherapy, but anthracycline usage showed only a very weak correlation. One third of patients (249/758) received two or more chemotherapy regimens. The response rate (16%) and median time to progression (2.3 months) were significantly worse than for first line treatment. The outcome after third line chemotherapy was very similar to that observed following second line treatment. Achievement of an objective response with first line chemotherapy predicted for second response, but with insufficient power to be of use in selecting patients for subsequent chemotherapy. Time to progression following first line chemotherapy did not influence that after second line treatment. 相似文献
46.
Anna Gasinska Jan Skolyszewski Tadeusz Popiela Piotr Richter Zbigniew Darasz Krystyna Nowak Joanna Niemiec Beata Biesaga Agnieszka Adamczyk Krzysztof Bucki Krzysztof Malecki Marian Reinfuss Teresa Kowalska 《Journal of gastrointestinal surgery》2007,11(4):520-528
Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal
cancer response to preoperative radiotherapy (RT).
Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I),
or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before
RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as
a percentage of BrdUrd-labeled cells.
Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before
RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically
significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical
and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios
were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with
overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation
was observed only in slowly proliferating tumors.
Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI
was correlated to inhibition of proliferation in responsive tumors.
The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France 相似文献
47.
Julian Knight 《Current infectious disease reports》2007,3(5):427-439
An increasing number of genetic association studies have implicated polymorphisms of cytokine genes as host genetic factors
influencing susceptibility to infectious disease, primarily using a candidate gene approach based on knowledge of disease
pathogenesis. The application and limitations of association studies are reviewed together with the impact of recent advances
in single nucleotide polymorphism mapping on strategic approaches to defining genetic susceptibility loci. It often remains
unclear whether associated genetic polymorphisms are themselves functionally relevant or acting only as markers within an
extended haplotype, and experimental approaches to investigating the functional impact of polymorphisms in noncoding regulatory
DNA sequences are discussed. An overview of genetic associations of cytokine genes with infectious disease is presented, together
with discussion of recent studies in a number of infectious diseases including hepatitis, HIV, malaria, and sepsis. 相似文献
48.
49.
M. Al-lsmaily A. AI-Khussaiby I. G. Chestnutt K. W. Stephen A. AI-Riyami M. Abbas M. Knight 《Community dentistry and oral epidemiology》1996,24(5):362-363
Abstract This study reports the first ever national oral health survey of Omani 12-year-olds. Conducted in October 1993, of the 3,435 children examined, 1,438 (41.9%) were caries-free, although regional variations ranged from 24.8% to 61.9%. Overall, the national DMFT averaged 1.53, the majority of caries experienced being in the form of untreated decay, with occlusal surfaces of first permanent molars being the most commonly involved site. Oral hygiene was poor, only 11% of those examined being scored as plaque-free. 相似文献
50.
Jonathan C. Craig Les M. Irwig James Christie Albert Lam Ella Onikul John F. Knight Premala Sureshkumar L. Paul Roy 《Pediatric nephrology (Berlin, Germany)》1997,11(4):455-459
Variability in the interpretation of micturating cystourethrography by paediatric radiologists for the diagnosis of vesicoureteric
reflux in children was evaluated. All 265 micturating cystourethrograms (MCUs) that were available from 304 consecutive children
aged 0.5 – 61 months – who were investigated after their first urine infection between 1993 and 1995 as part of a prospective
cohort study – were selected for interpretation. Three experienced paediatric radiologists from the same department independently
interpreted the MCUs according to the grading system of the International Reflux Study in Children, from grades 0 to V, with
the presence of intrarenal reflux also noted. Apart from being informed that urine infection was the indication for the MCU,
no other clinical information was given to the radiologists. The indices of variability used were the percentage of agreement
and the kappa statistic, expressed as a percentage. Both measures were weighted with integers representing the number of categories
from perfect agreement. Disagreement was analysed for children and kidneys. For the diagnosis of vesicoureteric reflux in
individual patients, including grade, the percentage of agreement was 96% – 97% (kappa 90% – 91%) and the weighted percentage
of agreement was 96% – 98% (weighted kappa 93% – 94%). The same high level of agreement was present for individual kidneys,
with a percentage of agreement of 97% – 98% (kappa 89% – 92%) and a weighted percentage of agreement of 98% – 99% (kappa 94% – 95%).
There was near perfect agreement in the interpretation of radiological micturating cystourethrography among three experienced
paediatric radiologists for the diagnosis and grade of vesicoureteric reflux. Any variations in the medical care of children
suspected of having vesicoureteric reflux are not explained by differences in the reporting of this diagnostic test.
Received June 19, 1996; received in revised form November 1, 1996; accepted December 6, 1996 相似文献