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101.
An established fish cell line, epithelioma papillosum cyprini (EPC), originating from the carp (Cyprinus carpio) was found to be susceptible to the penaeid shrimp virus, infectious hypodermal and hematopoietic necrosis virus (IHHNV). This economically important pathogen of penaeid shrimp raised in mariculture has been previously limited to growth only in young post-larval shrimps. This is, to our knowledge, the first reported successful growth of the penaeid virus in a fish cell line; it promises to provide a sensitive and convenient cell culture system for the primary isolation and detection of IHHNV which will aid immensely the production of IHHNV-free penaeid shrimp stocks for mariculture. Of added significance is the replication of a crustacean virus in a fish cell line which has never before been reported. The use of this sensitive cell line will also greatly facilitate the characterization of the IHHN virus and other crustacean viruses.  相似文献   
102.
During thymic development, immature thymocytes expressing major histocompatibility complex (MHC) class I-restricted T cell receptors (TcR) differentiate into CD8+ T cells with cytolytic functions. To evaluate the role of CD8 in positive and negative selection during thymic ontogeny, mice rendered CD8-null by gene targeting were bred with three lines of transgenic mice expressing unique MHC class I-restricted TcR. In all three instances CD8 was required for positive selection of MHC class I-restricted transgenic T cells. The efficiency of positive selection decreased in accordance with a reduced level of CD8 expression on thymocytes. Surprisingly, there was a differential requirement for CD8 expression in negative selection of MHC class I-restricted thymocytes, depending on the antigen specificity of TcR. These observations show that CD8 is essential for positive selection but is differentially required for negative selection of MHC class I-restricted T cells. Thus thymic selection, at least for negative selection, can occur in the absence of the CD8 accessory molecule.  相似文献   
103.
We present a case (41 years old pregnant female) with epithelioid sarcoma arising in the left external auditory canal. On immunohistochemistry, the tumor cell diffusely expressed cytokeratins and showed patchy expression of ERG and CD34. The neoplastic cells demonstrated uniform loss of INI1-expression. Epithelioid sarcoma arising in the external auditory canal is rare. Awareness that ES may rarely arise at unusual sites is of critical importance in order to apply a broad enough panel in the immunohistochemical study, so a misdiagnosis of carcinoma can be avoided.  相似文献   
104.
105.
The authors studied the impact of edge enhancement and gray scale polarity reversal on the detection of subtle lung cancers. Three experienced readers reviewed 46 biopsy-proved subtle lung cancers and 46 normal controls on chest radiographs that had been digitized into a 1,024 X 1,536-pixel matrix 8 bits deep. Receiver-operating characteristics (ROC) analysis of 1,656 pooled observations indicated that performance was best with the unmodified images (ROC area = 0.83), degraded by moderate enhancement of medium frequencies (ROC area = 0.80), and markedly impaired by severe enhancement of low frequencies (ROC area = 0.69). Gray scale polarity reversal further degraded performance (unenhanced ROC area = 0.74; moderately enhanced ROC area = 0.76; severely enhanced ROC area = 0.76). The authors conclude that edge enhancement and gray scale polarity reversal can impair the detectability of subtle lung cancers on digitized radiographs of medium resolution.  相似文献   
106.
107.
AIMS: The purpose of this study was to identify health characteristics of people with intellectual disabilities (ID) and to assess the use of emergency care facilities by these people and factors affecting this utilization. METHOD: A cross-sectional study was employed. Subjects were recruited from the Taiwan National Disability Registration System. A total of 1071 people registered with ID in Taiwan were recruited for this study in 2001. Data were collected via a structured mail-out questionnaire that was completed by the main carers of people with ID. RESULTS: Most of the carers subjectively characterized the overall health status of people with ID as good-excellent. However, people with ID carry a burden of diseases greater than that of the general population. Nearly half (47.7%) of the subjects reported having an illness in the past 7 months. Most of the morbidity was associated with neurological, psychiatric, digestive, dermatological and cardiovascular diseases or disorders. One-third of subjects took medication regularly and 15% were 'Major Illness' card beneficiaries of the Taiwan National Health Insurance scheme. About two-thirds of individuals with ID were classified as having multiple disabilities and 24.5% needed to be provided with frequent rehabilitative therapies to maintain their normal daily functions. Respondents indicated that 18.4% of the subjects had used emergency care in the past 7 months. A stepwise logistic regression model highlighted that the following need factors were significantly related to the utilization of emergency care: having an illness (OR=2.1, 95% CI=1.2-3.6), taking medicine regularly (OR=1.8, 95% CI=1.1-2.9) and self-reported health status (poor health: OR=9.9, 95% CI=2.1-45.7; bad health: OR=8.2, 95% CI=1.3-49.8). CONCLUSIONS: To ensure that people with ID minimize their utilization of emergency care, it is necessary to establish in appropriate community systems to monitor individuals with ID with poor health status, diseases and who take medicine regularly.  相似文献   
108.
Apoptosis has been well documented to play a significant role in cell loss during neurodegenerative disorders, such as stroke, Parkinson disease, and Alzheimer's disease. In addition, reactive oxygen species (ROS) has been implicated in the cellular damage during these neurodegenerative disorders. These ROS can react with cellular macromolecular through oxidation and cause the cells undergo necrosis or apoptosis. The control of the redox environment of the cell provides addition regulation in the signal transduction pathways which are redox sensitive. Recently, many researches focus on the relationship between apoptosis and oxidative stress. However, till now, there is no clear and defined mechanisms that how oxidative stress could contribute to the apoptosis. This review hopes to make clear that generation of ROS during brain injury, particularly in ischemic stroke and Alzheimer's Disease, and the fact that oxidative state plays a key role in the regulation and control of the cell survival and cell death through its interaction with cellular macromolecules and signal transduction pathway, and ultimately helps in developing an unique therapy for the treatment of these neurodegenerative disorders.  相似文献   
109.
The present study based on World Health Organization quality of life (WHOQOL-BREF) scale to examine quality of life of the caregivers caring for their children/adolescents with intellectual disabilities in Taiwan, and the factors contributing to their quality of life. Structured interviews were conducted with 597 caregivers of children/adolescents with intellectual disabilities. The results found that the mean scores in each domain of WHOQOL-BREF of the caregivers as the followings: physical capacity (PC) was 13.71 ± 2.35, psychological well-being (PW) was 12.21 ± 2.55, social relationship (SR) was 12.99 ± 2.43 and environment (EN) was 12.32 ± 2.38. These mean scores were lower than the general population and slight higher than the caregivers of adults with intellectual disabilities in Taiwan. Finally, multiple stepwise regressions were conducted to examine the characteristics of caregiver and children/adolescents with intellectual disabilities will more likely explained the WHOQOL-BREF mean scores. The study found the following three factors: self-perceived health status, household income and stress from insufficient family support were significantly correlated to all four domains in multiple stepwise regression analyses. The results highlights that caregivers of children and adolescents with intellectual disabilities seem to display a lower WHOQOL-BREF mean score than the general population, probably for a combination of stress, health and household income factors. These finding must be taken into account in policy making to provide better and more specific supports and interventions for the caregivers of people with intellectual disabilities.  相似文献   
110.
Previously, we have shown that mice deficient in either vasoactive intestinal peptide (VIP) or pituitary adenylate cyclase‐activating polypeptide (PACAP) exhibit specific deficits in the behavioral response of their circadian system to light. In this study, we investigated how the photic regulation of the molecular clock within the suprachiasmatic nucleus (SCN) is altered by the loss of these closely‐related peptides. During the subjective night, the magnitude of the light‐induction of FOS and phosphorylated mitogen‐activated protein kinase (p‐MAPK) immunoreactive cells within the SCN was significantly reduced in both VIP‐ and PACAP‐deficient mice when compared with wild‐type mice. The photic induction of the clock gene Period1 (Per1) in the SCN was reduced in the VIP‐ but not in the PACAP‐deficient mice. Baselines levels of FOS, p‐MAPK or Per1 in the night were not altered by the loss of these peptides. In contrast, during the subjective day, light exposure increased the levels of FOS, p‐MAPK and Per1 in the SCN of VIP‐deficient mice, but not in the other genotypes. During this phase, baseline levels of these markers were reduced in the VIP‐deficient mice compared with untreated controls. Finally, the loss of either neuropeptide reduced the magnitude of the light‐evoked increase in Per1 levels in the adrenals in the subjective night without any change in baseline levels. In summary, our results indicate that both VIP and PACAP regulate the responsiveness of cells within the SCN to the effects of light. Furthermore, VIP, but not PACAP, is required for the appropriate temporal gating of light‐induced gene expression within the SCN.  相似文献   
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