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991.
J Ludmir M B Landon S G Gabbe P Samuels M T Mennuti 《American journal of obstetrics and gynecology》1987,157(3):665-669
Over a 5-year period we have managed 63 diethylstilbestrol-exposed pregnant patients with a standardized protocol requiring weekly cervical examination and decreased physical activity of the patient. Twenty-six patients (42%) underwent a prophylactic cerclage for a history of second-trimester loss or a hypoplastic cervix on initial clinical examination (group I). Thirty-six patients (58%) were followed expectantly (group II). Sixteen patients (44%) in group II demonstrated cervical change and required an emergency cerclage. Twenty-one patients were managed expectantly with no cerclage. The gestational age at delivery for group I was 37.7 +/- 2.80 versus 34.5 +/- 6.9 weeks for patients without a cerclage (p = 0.04). There were no perinatal deaths if a cerclage was performed, whereas there were five deaths (24%) in the group without cerclage. The five deaths occurred at a mean gestational age of 24.40 +/- 4.0 weeks and a mean birth weight of 614.00 +/- 441.73 gm. Patients with a hypoplastic cervix or prior reproductive loss had a better outcome with early cerclage than patients with a normal cervix followed expectantly. We presently lack a reliable method to detect the diethylstilbestrol-exposed patient at greatest risk for perinatal loss. Based on our experience we believe that placement of a cerclage early in pregnancy should be a strong consideration. 相似文献
992.
Stephen Halpern Phyllis Glanc Terri Myhr Marylou Ryan Katherine Fong Kofi Amankwah Arne Ohlsson 《Journal canadien d'anesthésie》1994,41(11):1057-1062
The purpose of this study was to use colour Doppler to determine the effect of epidural anaesthesia on the uterine and umbilical blood flow velocities. After determining the precision of the technique, Doppler insonation of the uterine and umbilical arteries was performed in consenting non-labouring patients requesting epidural anaesthesia for Caesarean section. Patients in Group I were normal and those in Group II were at high risk for uteroplacental blood flow abnormalities. The pulsatility indexes (PI) of both uterine and umbilical arteries were compared at the following times: control, after fluid and after anaesthesia using repeated measure analysis of variance. In Group I (n = 30) the PI increased from 0.72 to 0.82 in the left uterine artery and from 0.71 to 0.85 in the right uterine artery (P < 0.05). In Group II (n = 10) the PI increased from 0.67 to 0.85 in the left uterine artery (NS) and from 0.98 to 1.38 in the right uterine artery (P < 0.05). There was no change in the PI in the umbilical artery. We conclude that the PI of the uterine arteries increases after epidural anaesthesia with lidocaine, epinephrine and fentanyl but there is no change in the umbilical PI. While these changes do not appear to be clinically important in the low-risk population, further studies are required to determine the impact on fetuses at high risk for in utero hypoxaemia. 相似文献
993.
Wyszynski DF Albacha-Hejazi H Aldirani M Hammod M Shkair H Karam A Alashkar J Holmes TN Pugh EW Doheny KF McIntosh I Beaty TH Bailey-Wilson JE 《American journal of medical genetics. Part A》2003,(2):140-147
Non-syndromic cleft lip with/without cleft palate (CL/P) is a common, usually non-fatal birth defect of complex etiology. Several segregation analyses have demonstrated that genetic factors are important in the pathogenesis of CL/P, most likely through the interaction of several genes of modest effects. The aim of this study was to perform a genome-wide linkage analysis to identify/search for candidate gene loci for CL/P. We conducted a genome-wide search in two large, relatively isolated Syrian families, each one with a large number of cases with CL/P (18 in family 1 and 4 in family 2). A locus with a multipoint LOD score of 2.80 and a 2-point non-parametric MLS LOD of 3.0 was detected on 17p13.1. Other chromosomal regions with multipoint LOD scores > or = 1.2 (P < or = 0.01) included 3p21.2, 4q32.1, and 7q34. These data indicate the possible presence of several susceptibility loci for CL/P and identify a strong candidate locus for this common birth defect on chromosome 17p13. 相似文献
994.
Nocardia asteroides causes an acute, necrotizing pneumonia characterized by extensive infiltration of polymorphonuclear neutrophils (PMNs) into the lungs. Although PMNs have historically been classified as end-point cells, recent investigations have indicated that PMNs have the ability to secrete cytokines such as interleukin (IL)-4 and IL-12. This study investigated the ability of PMNs to produce cytokines in a murine model of N. asteroides pulmonary infection. Flow cytometric analysis demonstrated the production of interferon-gamma (IFN-gamma), but not IL-4, by PMNs in response to this infection. IFN-gamma production correlated with peak infiltration of PMNs into the lungs. Cell sorting and enzyme-linked immunosorbent assay were used to confirm cytokine production by cells with nuclear morphology characteristic of PMNs. This is the first report of IFN-gamma production by neutrophils in response to an infection in vivo. These results suggest that PMNs play an important role in directing the host toward a T helper cell type 1 phenotypic response in the lungs. 相似文献
995.
996.
Terri L. Johnson Christine L. M. Joseph T. Jann Caison-Sorey Richard E. Smith Carlos W. M. Bedrossian Fazlul H. Sarkar 《Diagnostic cytopathology》1994,10(3):276-283
Adolescents may be more susceptible to cervical human papillomavirus (HPV) infections and may have more rapid progression of cervical intraepithelial neoplastic (CIN) lesions than adults. We evaluated Papanicolaou (Pap) smears and cervical tissue specimens from a consecutive series of 25 adolescent (age 15-20 yr) and 17 adult (age 35-40 yr) patients with a histologic diagnosis of CIN III. The study patients were all Detroit residents enrolled in a health maintenance organization (HMO) affliated with Henry Ford Hospital. The cervical tissue specimens were evaluated for HPV 6b/11, HPV 16, and HPV 18 using agarose gel electrophoresis and Southern hybridization following polymerase chain reaction (PCR) DNA amplification. While the small sample size precluded testing for statistical significance, HPV 16 and/or HPV 18 DNA was detected in specimens from 21/25 (84%) adolescents compared to 12/17 (71%) adults (odds ratio [OR] = 2.2; 95% confidence interval [CI] = 0.49-9.74). The relationship between adolescence and HPV infections appears to be stronger for HPV 18 and mixed HPV 16/18 infections (OR = 5.6; 95% CI = 0.7-42.4) than for HPV 16 infections (OR = 1.93; 95% CI = 0.4-8.8). None of the cervical specimens contained HPV 6b/11 DNA. Oral contraceptive (OC) use was associated with HPV infection in patients with CIN III, but there was no association between cigarette smoking and HPV infection. The effect of OC use on the relationship of age and HPV could not be evaluated due to small sample size. The effects of previous sexually transmitted disease (STD) on the relationship of age and HPV were assessed. Among women with a history of STD, there was a strong association between HPV and adolescent age (OR = 18.0; 95% CI = 1.2-260.0). Our data suggest that among women with CIN III, adolescents have a higher prevalence of certain high-risk types of HPV infections than adults. The excess is due predominantly to the higher rates of HPV 18 and mixed HPV 16/18 infections in adolescents. The positive relationship between high-risk HPV infections and young age was most evident in adolescents with a history of STD. The results from this study suggest that differences in HPV type infections may be related to the more aggressive clinical course of CIN in adolescents. © 1994 Wiley-Liss, Inc. 相似文献
997.
Enzyme-cleaved antibodies are used widely for the treatment of envenoming. Such products should comprise only 'highly pure' immunoglobulin fragments since Fc or other contaminating protein fragments or their aggregates may lead to side effects. The digestion of ovine antiserum and its purified IgG were investigated using pepsin and trypsin. Trypsin was effective at digesting purified IgG but unsuitable for the direct digestion of serum. In contrast, pepsin was highly effective at digesting all unwanted serum components to low molecular weight (< or =13 kDa) fragments while leaving the approximately 100-kDa F(ab')(2) intact. The optimum pH for pepsin digestion was between 3.25 and 3.50. The effects of salt concentration and pH on the digestion products were investigated by size exclusion chromatography under various conditions, which revealed a pH-dependent aggregation of some of the low molecular weight Fc and non-IgG fragments. These high molecular weight aggregates were not shown by SDS-PAGE. Unwanted low molecular weight fragments could be removed simply by diafiltration with a 30-kDa nominal molecular weight cutoff membrane and piperazine buffer (containing 150 mM NaCl, pH 6), leaving an F(ab')(2) solution contaminated only with some pepsin and a small amount of the aggregated low molecular weight fragments. These highly acidic contaminants were then removed easily using an anion exchange column and the F(ab')(2) produced following a subsequent concentration step was essentially free from pepsin and aggregates with a purity of over 96% and a yield of 19.3 g F(ab')(2)/l serum. This novel, high yield method for processing serum to highly pure F(ab')(2) avoids salt precipitation and centrifugation and should be suitable for large-scale production. 相似文献
998.
A filamentous inclusion body within anterior horn neurones in motor neurone disease defined by immunocytochemical localisation of ubiquitin 总被引:5,自引:0,他引:5
J Lowe G Lennox D Jefferson K Morrell D McQuire T Gray M Landon F J Doherty R J Mayer 《Neuroscience letters》1988,94(1-2):203-210
Using an immunocytochemical method to localise antibodies to ubiquitin, filamentous inclusion bodies were seen in spinal anterior horn neurones in cases of motor neurone disease (MND) but not in any control cases. These inclusion bodies appeared to be closely associated with classical Bunina bodies and immuno-electron microscopy suggested that they were based on arrays of straight 10-15 nm filaments together with some granular material. These observations link the protein ubiquitin with a chronic neurodegenerative disease and extend previous observations of a close association between filamentous inclusion bodies and ubiquitin. Ubiquitin-filament inclusions should be regarded as a new hallmark in the histological diagnosis of MND. 相似文献
999.
Ubiquitin is a component of neurofibrillary tangles in a variety of neurodegenerative diseases 总被引:2,自引:0,他引:2
Ubiquitin has been shown to be a component of neurofibrillary tangles in Alzheimer's disease. We now show immunocytochemically that it is also a component of neurofibrillary tangles in several other neurodegenerative diseases of diverse aetiology, including Down's syndrome, dementia pugilistica and postencephalitic parkinsonism, and in normal ageing. Ubiquitin immunoreactivity is not, however, generally found in the neurofibrillary tangles of progressive supranuclear palsy. These findings show that while associated ubiquitin is not a feature unique to the tangles of Alzheimer's disease, it is not simply a non-specific response to the presence of an inclusion body within the cell. The observations suggest that ubiquitin may have an important role in the formation of neurofibrillary tangles in a variety of neurodegenerative diseases. 相似文献
1000.
Association between IRF6 and nonsyndromic cleft lip with or without cleft palate in four populations. 总被引:2,自引:0,他引:2
Ji Wan Park Iain McIntosh Jacqueline B Hetmanski Ethylin Wang Jabs Craig A Vander Kolk Yah-Huei Wu-Chou Philip K Chen Samuel S Chong Vincent Yeow Sun Ha Jee Beyoung Yun Park M Daniele Fallin Roxann Ingersoll Alan F Scott Terri H Beaty 《Genetics in medicine》2007,9(4):219-227
PURPOSE: The interferon regulatory factor 6 (IRF6), the gene that causes van der Woude syndrome has been shown to be associated with nonsyndromic cleft lip with or without palate in several populations. This study aimed to confirm the contribution of IRF6 to cleft lip with or without palate risk in additional Asian populations. METHODS: A set of 13 single nucleotide polymorphisms was tested for association with cleft lip with or without palate in 77 European American, 146 Taiwanese, 34 Singaporean, and 40 Korean case-parent trios using both the transmission disequilibrium test and conditional logistic regression models. RESULTS: Evidence of linkage and association was observed among all four populations; and two specific haplotypes [GC composed of rs2235373-rs2235371 (p.V274I) and AAG of rs599021-rs2235373-rs595918] showed the most significant over- and undertransmission among Taiwanese cases (P=9x10(-6) and P=5x10(-6), respectively). The AGC/CGC diplotype composed of rs599021-rs2235373-rs2013162 showed almost a 7-fold increase in risk among the Taiwanese sample (P<10(-3)). These results confirmed the contribution of this gene to susceptibility of oral clefts across different populations; however, the specific single nucleotide polymorphisms showing statistical significance differed among ethnic groups. CONCLUSION: The high-risk genotypes and diplotypes identified here may provide a better understanding of the etiological role of this gene in oral clefts and potential options for genetic counseling. 相似文献