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101.
AC Lidral PA Romitti AM Basart T Doetschman NJ Leysens S Daack-Hirsch EV Semina LR Johnson J Machida A Burds TJ Parnell JL Rubenstein JC Murray 《Canadian Metallurgical Quarterly》1998,63(2):557-568
Nonsyndromic cleft lip with or without cleft palate (CL/P) and nonsyndromic cleft palate only (CPO) are common congenital anomalies with significant medical, psychological, social, and economic ramifications. Both CL/P and CPO are examples of complex genetic traits. There exists sufficient evidence to hypothesize that disease loci for CL/P and CPO can be identified by a candidate-gene linkage-disequilibrium (LD) strategy. Candidate genes for clefting, including TGFA, BCL3, DLX2, MSX1, and TGFB3, were screened for LD with either CL/P or CPO in a predominantly Caucasian population, with both case-control- and nuclear-family-based approaches. Previously reported LD for TGFA with both CL/P and CPO could not be confirmed, except in CL/P patients with a positive family history. Also, in contrast to previous studies, no LD was found between BCL3 and either CL/P or CPO. Significant LD was found between CL/P and both MSX1 and TGFB3 and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2, MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of the CL/P patients. No common mutations were found in the coding regions of these genes; however, several rare variants of MSX1 and TGFB3 were found that may alter the latters' normal function. These results form the basis for future research, including (a) mutation searches in the MSX1 and TGFB3 genes in Caucasian CL/P patients and (b) extension of the search for MSX1 mutations in CPO patients to the noncoding regions. 相似文献
102.
Kartagener's syndrome (KS) usually includes mirror-image dextrocardia. The incidence of congenital heart disease in KS is comparable with that in the general population. This paper reports on a case of Kartagener's syndrome associated with dextrocardia, corrected transposition of the great arteries (I,D,D), ventricular septal defect, and valvar pulmonary stenosis in an 8-year-old girl. 相似文献
103.
U Schiefer M Skalej M Kolb TJ Dietrich R Kolb C Braun D Petersen 《Canadian Metallurgical Quarterly》1998,38(9):1303-1312
An attempt was made to clarify whether the site of postchiasmal lesions affects subjective perception of homonymous visual field defects during stimulation with flickering random dot patterns (white noise-field). Out of 56 patients with homonymous hemianopia, 38 (68%) perceived scotomata in this situation, but 18 (32%) discerned none at all. Neuroradiologic superposition of cerebral lesions detected by computed tomography (CT) or magnetic resonance imaging (MRI) showed that nearly all patients who perceived their scotomata had lesions involving the primary visual cortex or the perigeniculate region, whereas those who received no scotoma had lesions centered within the optic radiation. Functional MRI of six normal subjects during stimulation with flickering random dot patterns indicated predominant activation of the primary visual cortex. Since noise-field defects were most frequently perceived by patients whose lesion involved the primary visual cortex, it appears that the sensitivity of noise-field campimetry depends on the site of damage in the visual pathway. The explanation for this may be that damage to long-range horizontal connections impairs filling-in processes. 相似文献
104.
PURPOSE: We studied the frequency of testicular microlithiasis (TM) in a select group of otherwise healthy infertile men with abnormal semen. METHODS: We reviewed scrotal sonography records of 180 consecutive patients with abnormal semen who were referred for evaluation of male infertility. The pampiniform plexus was evaluated for possible varicocele, and the testes were examined for the presence or absence of intratesticular calcifications and/or masses. Five patients with more than 5 echogenic foci per transducer field in either testis were identified. The medical records and sonograms of this subgroup of patients were analyzed. RESULTS: Of the 180 patients, 5 (2.8%) had TM. Three patients with TM had concomitant small varicoceles; 2 others had a history of testicular maldescent. Two patients eventually became fertile. CONCLUSIONS: Our results indicate a higher than expected frequency of TM in otherwise healthy infertile men. We speculate that the magnitude of hypospermatogenesis in patients with TM is variable and may relate to both the degree of testicular dysgenesis and the presence or absence of concomitant scrotal pathology (eg, scrotal varicocele and cryptorchidism). 相似文献
105.
TJ Christmas AP Doherty GJ Rustin MJ Seckl ES Newlands 《Canadian Metallurgical Quarterly》1997,84(7):1022-1025
BACKGROUND: Primary retroperitoneal germ cell tumours usually present as a large abdominal mass in young men. The testes are normal on examination and ultrasonography but there are usually raised serum levels of human chorionic gonadotrophin and/or alpha-fetoprotein. METHODS: Fourteen men (median age 33 years) with primary retroperitoneal germ cell tumours were treated by chemotherapy followed by surgical resection of the primary tumour and metastases via a thoracoabdominal extraperitoneal approach. RESULTS: There was minimal morbidity. The survival rate was 13 of 14 and the disease-free survival rate was 11 of 14 after a median follow-up of 15 months. CONCLUSION: The thoracoabdominal extraperitoneal approach for the removal of retroperitoneal germ cell tumours and their metastases after chemotherapy improves tumour clearance, morbidity and recovery time compared with the transperitoneal anterior approach. 相似文献
106.
PURPOSE: To quantify the workload of residents on night call and to determine the residents' perceptions of the balance between service and education in their night-call activities. METHOD: Twenty-two internal medicine residents--nine first-year residents and 13 senior residents (i.e., in their second, third, or fourth year)--kept logs of their night-call activities for two periods of 16 days each in 1991-92, at a 772-bed teaching hospital affiliated with Wright State University School of Medicine. The residents used the following five-point scale to rate each activity: 1, strictly service; 3, even balance; 5, strictly education. They also recorded the total times spent on various activities. Data were analyzed by using the independent and paired t-tests. RESULTS: Ninety-eight percent of the logs were returned. The first-year and senior residents did not differ significantly in times spent on logged events. Both the first-year and the senior residents perceived many night-call activities to be weighted toward education, especially those involving evaluation of acutely ill patients being considered for hospital admission (overall mean rating of 3.3). There was no striking difference between the first-year and senior residents' perceptions of the balance between service and education in their activities. CONCLUSION: The residents' perceptions of the relationship between service and education indicate that there was an even balance between the two. The educational aspects of night-call duties can and should remain an integral part of residents' training. 相似文献
107.
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109.
Aging differentially affects receptor function. In the present electrophysiological study we compared neuronal responsiveness to locally applied dopamine D1 and D2 receptor agonist in the striatum of female Fischer 344 rats aged 3 and 26-27 months. In a subgroup of the old rats, the nigrostriatal dopamine bundle was destroyed unilaterally with 6-hydroxydopamine (6-OHDA) to assess receptor plasticity in response to denervation. Spontaneous firing rate of striatal neurons was higher in aged compared to young rats. Higher doses of the D1 agonist SKF 38393 or the D2 agonist quinpirole were required to elicit a 50% change in firing rate in aged compared to young rats. No difference with SKF 38393 or quinpirole was detected between 6-OHDA denervated and control (nonlesioned) striatum in aged rats. Supersensitivity to D2 agonists has been reported following 6-OHDA lesions in young rats. These observations suggest that D2 receptors in aged rat striatum might not be as plastic as in younger rats. 相似文献
110.
Ependymomas are rare neuroectodermal tumors arising from ependymal cells of the ventricular system, choroid plexus, filum terminale, and central canal of the spinal cord (1,2). This review focuses on intracranial ependymomas with special emphasis on pathology, etiology, cytogenetic characteristics, and adjuvant radiation therapy. Recent advances in neurosurgical technique, radiation therapy, and molecular biology have affected management of these tumors and have the potential to increase long-term cure rates. The role of highly advanced radiation therapy techniques such as stereotactic radiosurgery will need to be better defined. 相似文献