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排序方式: 共有3154条查询结果,搜索用时 31 毫秒
31.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
32.
Barnetson R Jass J Tse R Eckstein R Robinson B Schnitzler M 《Genes, chromosomes & cancer》2000,29(2):130-136
Although microsatellite instability (MSI) has been shown to be present in 15% of sporadic colorectal carcinomas, the genetic events underlying the development of these tumors have not been well described. By investigating intratumoral heterogeneity, this study attempts to elucidate whether MSI-positive colorectal carcinomas develop as the result of a random accumulation of mutations or as an ordered, stepwise sequence of genetic alterations. Eighty-six regions from 16 MSI-positive sporadic colorectal carcinomas were examined for mutations in repeat nucleotide sequences of the tumour suppressor genes transforming growth factor beta type II receptor (TGFBRII), insulin-like growth factor II receptor (IGFIIR), and BAX, and the mismatch repair genes MSH3 and MSH6. At least 2 and up to 5 of these genes were mutated in each tumour, and widespread intratumoral heterogeneity was observed for each gene. Regions of tumour with TGFBRII mutations were correlated with a poorly differentiated histology. Unlike the situation in microsatellite stable colorectal carcinomas, the findings of the present study did not suggest that a particular sequence of tumour suppressor and mismatch repair genes are mutated during colorectal tumorigenesis. It seems likely that a random accumulation of mutations, as a result of a defect in the mismatch repair pathway, drives tumour progression in this type of colorectal carcinoma. 相似文献
33.
Climacteric symptoms and knowledge about hormone replacement therapy among Hong Kong Chinese women aged 40-60 years 总被引:1,自引:0,他引:1
OBJECTIVES: To evaluate the use of hormone replacement therapy (HRT), the prevalence of climacteric symptoms, and the knowledge about HRT. METHODS: A prospective study was conducted by telephone interview among a randomly selected population-based sample of 978 Hong Kong Chinese women aged 40-60 years. RESULTS: Of 414 women with a history of either natural or surgical menopause, 22 (5.3%) and 17 (4.1%), respectively, were either past or current users of HRT. The climacteric symptom scores of premenopausal women were significantly lower than those of perimenopausal women, but were comparable with those of postmenopausal women. The commonest climacteric symptom was 'muscle and joint pains' which was reported in 553 (56.6%) women, while only 228 (23.3%) and 151 (15.4%) women reported hot flushes and night sweating, respectively. Moreover, only 230 (23.5%) women realized that HRT could relieve menopausal symptoms and only 33 (3.4%) women were aware that HRT was protective against osteoporosis. In general, women with more climacteric symptoms, who had ever used HRT, and those with higher education level and higher family income, had better knowledge about HRT. CONCLUSIONS: Postmenopausal Hong Kong Chinese women have a low HRT usage rate and the majority of them are lacking of the knowledge about HRT. 相似文献
34.
35.
Wayne Kepron June M. James Bryan Kirk Alec H. Sehon Kam S. Tse 《The Journal of allergy and clinical immunology》1977,59(1):64-69
Immunization of neonatal dogs with a conjugate of 2,4-dinitrobenzene and ovalbumin (DNP2-OA), using aluminum hydroxide as the adjuvant, elicited long-lasting (over 30 wk) anti-DNP and anti-OA IgE antibody responses of high titers as determined by homologous passive cutaneous anaphylaxis. Low antigen doses of 10 or 50 μg were more effective than the higher doses of 250 or 1,250 μg in inducing high IgE antibody levels. However, this method of immunization failed to elicit any detectable IgE antibody response in adult dogs. Bronchoprovocation with antigen of sensitized animals having IgE antibody titers in excess of 64 resulted in a marked increase in airflow resistance, which could be corrected by the administration of nebulized isoproterenol. On the other hand, sensitized animals with IgE antibody titers in the order of 64 did not manifest significant bronchoconstriction on inhalation challenge but developed anaphylaxis following intravenous injection of the antigen. 相似文献
36.
Tse GM Tsang AK Putti TC Scolyer RA Lui PC Law BK Karim RZ Lee CS 《Journal of clinical pathology》2005,58(2):185-189
BACKGROUND/AIMS: CD10 (CALLA) has recently been reported to be expressed in spindle cell neoplasia, and has been used to differentiate endometrial stromal sarcoma from leiomyoma and leiomyosarcoma. In the breast, myoepithelial cells express CD10, but there are few studies of the expression of CD10 in mammary fibroepithelial lesions. METHODS: Stromal CD10 expression was studied in 181 mammary phyllodes tumours (102 benign, 51 borderline malignant, and 28 frankly malignant) and 33 fibroadenomas using immunohistochemistry, to evaluate whether differences in expression correlated with the degree of malignancy. RESULTS: There was a progressive increase in the patients' age and tumour size, from fibroadenoma to phyllodes tumours with an increasing degree of malignancy (p < 0.001). Stromal CD10 expression was positive in one of 33 fibroadenomas, six of 102 benign phyllodes tumours, 16 of 51 borderline malignant phyllodes tumours, and 14 of 28 frankly malignant phyllodes tumours. The difference was significant (p < 0.001) and an increasing trend was established. Strong staining was seen in subepithelial areas with higher stromal cellularity and activity. Stromal CD10 expression had a high specificity (95%) for differentiating between benign lesions (fibroadenomas and benign phyllodes tumours) and malignant (borderline and frankly malignant) phyllodes tumours. CONCLUSIONS: CD10 may be a useful adjunct in assessing malignancy in mammary fibroepithelial lesions. 相似文献
37.
Jeremy Yuen-Chun Teoh Terry Cheuk-Fung Yip Grace Chung-Yan Lui Vincent Wai-Sun Wong Viola Chi-Ying Chow Tracy Hang-Yee Ho Timothy Chun-Man Li Yee-Kit Tse Peter Ka-Fung Chiu Chi-Fai Ng David Shu-Cheong Hui Henry Lik-Yuen Chan Cheuk-Chun Szeto Grace Lai-Hung Wong 《Journal of the American Society of Nephrology : JASN》2021,32(4):961
BackgroundSevere acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19) are closely related. The effect of AKI on the clinical outcomes of these two conditions is unclear.MethodsThis retrospective, territory-wide cohort study used an electronic public healthcare database in Hong Kong to identify patients with SARS or COVID-19 by diagnosis codes, virologic results, or both. The primary endpoint was a composite of intensive care unit admission, use of invasive mechanical ventilation, and/or death.ResultsWe identified 1670 patients with SARS and 1040 patients with COVID-19 (median ages, 41 versus 35 years, respectively). Among patients with SARS, 26% met the primary endpoint versus 5.3% of those with COVID-19. Diabetes mellitus, abnormal liver function, and AKI were factors significantly associated with the primary endpoint among patients with either SARS or COVID-19. Among patients with SARS, 7.9%, 2.1%, and 3.7% developed stage 1, stage 2, and stage 3 AKI, respectively; among those with COVID-19, 6.6%, 0.4%, and 1.1% developed stage 1, stage 2, and stage 3 AKI, respectively. In both groups, factors significantly associated with AKI included diabetes mellitus and hypertension. Among patients with AKI, those with COVID-19 had a lower rate of major adverse clinical outcomes versus patients with SARS. Renal function recovery usually occurred within 30 days after an initial AKI event.ConclusionsAKI rates were higher among patients with SARS than those with COVID-19. AKI was associated with major adverse clinical outcomes for both diseases. Patients with diabetes mellitus and abnormal liver function were also at risk of developing severe consequences after SARS and COVID-19 infection. 相似文献
38.
39.
Jerry R. Nedelman Ekaterina Gibiansky Francis L. S. Tse Christine Babiuk 《Journal of pharmacokinetics and pharmacodynamics》1993,21(3):323-334
Five major objectives for pharmacokinetic investigations in support of toxicity studies are identified as follows: Assess whether animals exhibited measurable blood concentrations in a dose-dependent manner; estimate average area under the concentration- time curve (AUC)and maximal concentration (C
max
)for each treatment group; elucidate general patterns in the concentration-time (CxT)profile, and summarize relationships between CxTand treatment group; determine CxTdependence on day into study; and judge interanimal variability and identify any animals with unusual concentration response. Such objectives are generally addressed in rodent toxicity studies by including satellite animals in the study. Satellite animals are extra animals dosed as per protocol but not subjected to toxicological and pathological observations and tests. Instead, they are used exclusively for the evaluation of pharmacokinetic characteristics of the test compound. In this paper, methods are described for achieving the five listed pharmacokinetic objectives in rodent toxicity studies without the use of satellite animals. A rat toxicity study is presented as an example. 相似文献
40.
The aim of this study was to compare the linear growth of children with cerebral palsy (CP) with that of children without CP. The segmental lengths (humerus, ulna, femur, tibia, and spine), recumbent length, body weight, and bone age of 62 children with CP (age range 2.25 to 14 years, mean 7.13 years) were measured and compared with 68 children without CP (age range 1.50 to 12.67 years, mean 6.73 years). The results show that bone-age delay is common in children with CP (68% with a delay of more than 1 year). The linear growth of children with CP is similar to that of children without CP when bone age is used instead of chronological age. There is a strong correlation between segmental lengths and body height. Hence, this study favours using segmental lengths for estimating height in children with CP and using the comparison group as a reference for this purpose. Nutritional and non-nutritional factors on bone-age delay are discussed. 相似文献