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81.
Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.  相似文献   
82.
Cryptosporidium is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium hominis and Cryptosporidium parvum are the main agents of cryptosporidiosis in humans. In Egypt, very little is known about genetic structure of Cryptosporidium spp. Therefore, this study was designed to examine samples from sporadic cases of cryptosporidiosis in Egyptians in order to identify the species involved in infection as well as the transmission dynamics and distribution of the parasite in the Great Cairo area. A total of 391 human faecal samples were collected, between May 2008 and March 2009, from ten public hospitals in Great Cairo. Initial screening by immunochromatographic detection kit “the Stick Crypto-Giardia; Operon” showed 23 possible positive cases. Twenty of them were confirmed by microscopic examination. PCR was performed by amplification of the oocyst wall protein (COWP) gene where 18 out of 23 samples were positive, one not detected by microscopy. Cryptosporidium genotyping was performed by RFLP analysis of PCR products of the diagnosis PCR. Only 15 samples rendered a digestion pattern. The genotyping distribution was nine cases showing C. hominis genotype, three showing C. parvum genotype and three showing mixed infection by C. hominis and C. parvum. The data showed an elevated prevalence of C. hominis (80.0%), the most anthroponotic species, suggesting a human–human transmission. Furthermore, the presence of up to 40% of samples infected with C. parvum shows that further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures.  相似文献   
83.
The aim of this study was to analyze the influence of the sense of community (SOC) on satisfaction with life (SWL) in native and immigrant populations in Spain. The main hypothesis was that SOC would moderate the negative effects associated with the immigrant adaptation process. It was further hypothesized that there would be no differences in SWL between immigrants with a high SOC and the native population. The study included 1,646 participants living in Malaga (Spain), comprising 946 natives and 700 immigrants. Data were collected using random route sampling and survey methodology. The results showed that people with higher SOC had significantly greater SWL. It was also found that SWL was greater in natives than in immigrants when the level of SOC was low or medium. However, when SOC was high there were no significant differences between the groups in SWL. The data support the hypothesis that SOC acts as a moderating variable that buffers the effect of the adaptation process experienced by immigrants.  相似文献   
84.
Recent studies consider lifestyle risk score (LRS), an aggregation of multiple lifestyle exposures, in identifying association of gene-lifestyle interaction with disease traits. However, not all cohorts have data on all lifestyle factors, leading to increased heterogeneity in the environmental exposure in collaborative meta-analyses. We compared and evaluated four approaches (Naïve, Safe, Complete and Moderator Approaches) to handle the missingness in LRS-stratified meta-analyses under various scenarios. Compared to “benchmark” results with all lifestyle factors available for all cohorts, the Complete Approach, which included only cohorts with all lifestyle components, was underpowered due to lower sample size, and the Naïve Approach, which utilized all available data and ignored the missingness, was slightly inflated. The Safe Approach, which used all data in LRS-exposed group and only included cohorts with all lifestyle factors available in the LRS-unexposed group, and the Moderator Approach, which handled missingness via moderator meta-regression, were both slightly conservative and yielded almost identical p values. We also evaluated the performance of the Safe Approach under different scenarios. We observed that the larger the proportion of cohorts without missingness included, the more accurate the results compared to “benchmark” results. In conclusion, we generally recommend the Safe Approach, a straightforward and non-inflated approach, to handle heterogeneity among cohorts in the LRS based genome-wide interaction meta-analyses.Subject terms: Genetics, Risk factors  相似文献   
85.
发生于骶骨以上的脊柱骨巨细胞瘤罕见[1],关于其CT表现仅见零星个案报道。我院误诊1例,报告如下。患者男性,20岁。胸背部疼痛2月,加重伴双下肢麻木10天入院。病史中无明显咳嗽、潮热、盗汗现象。外院X线及CT提示第5胸椎体结核伴椎旁冷脓肿形成。专科检查:胸椎活动受限,尤以屈曲位为明显,第5胸椎处叩压痛明显,局部无明显畸形及包块,剑突平面以下痛觉略减退,双下肢踝阵挛阳性,双膝反射、踝反射亢进。实验室检查:肝功、肾功、电解质、CEA、AFP及血、尿常规均无异常,入院时ESR:41mm/h,1周后复查ESR:16mm/h,2周后复查ESR:37mm/h。影像表…  相似文献   
86.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
87.
Speech-controlled generation of radiology reports   总被引:1,自引:0,他引:1  
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.  相似文献   
88.
89.
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary.  相似文献   
90.
Malignant uveal melanoma and simulating lesions: MR imaging evaluation   总被引:7,自引:0,他引:7  
Twenty-one patients with intraocular disease were studied by magnetic resonance (MR) imaging and computed tomography (CT). In 13 cases, malignant uveal melanoma was considered the likely diagnosis. Both imaging methods were accurate in determining the location and size of uveal melanomas. MR imaging was superior for the assessment of possible associated retinal detachment, for assessment of vitreous change, and for differentiating uveal melanoma from choroidal hemangioma and choroidal detachment. A case of retinal gliosis could not be differentiated from uveal melanoma by either technique. Uveal melanomas appeared as hyperintense lesions on T1-weighted images and as hypointense lesions on T2-weighted images. High signal intensity of the vitreous was observed in patients with vitritis and in those who were thought to have protein leaking into the vitreous as a result of impairment of the retinal-blood barrier.  相似文献   
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