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51.
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   
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Nonobese diabetic (NOD) mice develop multi-organ autoimmune diseases, including type 1 diabetes. We hypothesized that backcrossing the MHC region from SJL (H-2(s)) mice, which have an endogenous PLP(139-151)-reactive repertoire, onto the background of autoimmune-prone NOD mice would result in a mouse strain that is highly susceptible to experimental autoimmune encephalomyelitis (EAE). Unexpectedly, although we detected an endogenous PLP(139-151) repertoire in the NOD.S mice, they did not develop spontaneous EAE and were relatively resistant to PLP(139-151)-induced EAE when compared to SJL mice. This resistance was associated with lower production of proinflammatory cytokines and a decreased expansion of PLP(139-151)-specific CD4(+) T cells after immunization and restimulation with PLP peptide in vitro. V(beta) chain usage among PLP(139-151)-reactive T cells differed between SJL and NOD.S mice. Furthermore, NOD.S mice were resistant to the development of insulitis and cyclophosphamide-induced diabetes, but not sialadenitis. Altogether, even though NOD mice develop spontaneous autoimmune diseases, they become relatively resistant to induction of EAE even when they express the EAE-permissive class II molecule I-A(s). Our data show that certain combinations of otherwise susceptibility-conferring MHC and non-MHC genes can mediate autoimmune-disease resistance when they are paired together. These findings do not support the "shared autoimmune gene" hypothesis.  相似文献   
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The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.   相似文献   
57.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
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ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold.  相似文献   
59.
Hypotony with reduced a reduced visual acuity is often seen after trabeculectomy with mitomycine. In this study we describe measures such as reattaching the sleral flap with at least seven nylon sutures and the controlled and delayed use of argon laser suture lysis. With these preventative measures the percentage of hypotonies (IOP 6 mmHg) three months after surgery was reduced from 38 to 15% and chronically reduced visual acuity was reduced from 38 to 5%. With these adaptations in the surgical technique the complication rate of trabeculectomies with mitomycine can be markedly reduced without affecting the mean IOP (10.9 mmHg versus 10.8 mmHg) three months after surgery and the percentage of eyes with IOP 18 mmHg or less without medication (94 versus 91%).  相似文献   
60.
Vascular concepts in glaucoma   总被引:5,自引:0,他引:5  
A relationship has been found among vascular risk factors, normal-tension glaucoma (NTG), and visual field progression. All these factors have been measured qualitatively. These factors are disc hemorrhages, peripapillary atrophy, myopic disc, choroidal sclerosis, slow filling of the choroid and veins, and vasospasms. Now we are in a transition period where more and more quantitative methods are becoming available: pulsatile ocular blood flow measurement (POBF), scanning laser angiography of the peripapillary choroid (SLAPPC), scanning laser angiography of the retinal circulation (SLARC), scanning laser Doppler flowmetry (SLDF), and color Doppler imaging. With POBF, SLAPPC, SLARC, and SLDF a deficient blood flow was found in at least 50% of patients with NTG. With these results a vascular pathogenesis of NTG becomes more and more evident.  相似文献   
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