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991.
This article examines practical workplace issues and recent developments related to collective bargaining in the nursing profession, with emphasis on issues affected by recent reforms in the healthcare industry. Included are examples of issues most salient to nurses in their efforts to organize, given the reforms. An overview of recent developments in the political, legal, and local areas is also provided.  相似文献   
992.
Fortification of cereal flours may be a useful public health strategy to combat iron deficiency. Cereal flours that are used shortly after production (e.g., baking flour) can be fortified with soluble iron compounds, such as ferrous sulfate, whereas the majority of flours stored for longer periods is usually fortified with elemental iron powders to avoid unacceptable sensory changes. Elemental iron powders are less well absorbed than soluble iron compounds and they vary widely in their absorption depending on manufacturing method and physicochemical characteristics. Costs vary with powder type, but elemental iron powders are generally less expensive than ferrous sulfate. This review evaluates the usefulness of the different elemental iron powders based on results from in vitro studies, rat assays, human bioavailability studies, and efficacy studies monitoring iron status in human subjects. It concludes that, at the present time, only electrolytic iron powder can be recommended as an iron fortificant. Because it is only approximately half as well absorbed as ferrous sulfate, it should be added to provide double the amount of iron.  相似文献   
993.
994.
The mechanisms of neuronal loss during the course of the prion diseases are not fully understood. In this study, neurones treated with certain non-steroidal anti-inflammatory drugs (NSAIDs) were protected against the otherwise toxic effects of a peptide derived from the prion protein, or extracts containing infectious prions (PrP ). These NSAIDs inhibit the cyclo-oxygenase (cox) enzymes that metabolise arachidonic acid to prostaglandins (PG). Conversely, drugs that inhibited the metabolism of arachidonic acid to leucotrienes enhanced neurotoxicity. Studies with selective inhibitors highlighted the importance of the cox-1 isoform in prion-induced neurotoxicity. The cox-1 inhibitors also inhibited neuronal PGE production and protected both neuroblastoma cells and primary cortical neurones against prions. They also reduced microglia-mediated killing of prion-treated neurones.  相似文献   
995.
996.
Impairment in social reciprocity is a central component of autism. In preclinical studies, arginine vasopressin (AVP) has been shown to increase a range of social behaviors, including affiliation and attachment, via the V(1a) receptor (AVPR1A) in the brain. Both the behavioral effects of AVP and the neural distribution of the V1a receptor vary greatly across mammalian species. This difference in regional receptor expression as well as differences in social behavior may result from a highly variable repetitive sequence in the 5' flanking region of the V1a gene (AVPR1A). Given this comparative evidence for a role in inter-species variation in social behavior, we explored whether within our own species, variation in the human AVPR1A may contribute to individual variations in social behavior, with autism representing an extreme form of social impairment. We genotyped two microsatellite polymorphisms from the 5' flanking region of AVPR1A for 115 autism trios and found nominally significant transmission disequilibrium between autism and one of the microsatellite markers by Multiallelic Transmission/Disequilibrium test (MTDT) that was not significant after Bonferroni correction. We also screened approximately 2 kb of the 5' flanking region and the coding region and identified 10 single nucleotide polymorphisms.  相似文献   
997.
Association between a GABRB3 polymorphism and autism   总被引:10,自引:0,他引:10  
Autistic disorder (OMIM 209850) is a disease with a significant genetic component of a complex nature.(1) Cytogenetic abnormalities in the Prader-Willi/Angelman syndrome critical region (15q11-13) have been described in several individuals with autism.(1) For this reason, markers across this region have been screened for evidence of linkage and association, and a marker (155CA-2) in the gamma-aminobutyric acid type-A receptor beta3 subunit gene (GABRB3) has been associated in one study(2) but not others.(3-5) We completed an association analysis with 155CA-2 using the transmission disequilibrium test (TDT) in a set of 80 autism families (59 multiplex and 21 trios). We also used four additional markers (69CA, 155CA-1, 85CA, and A55CA-1) localized within 150 kb of 155CA-2. The use of multi-allelic TDT (MTDT) (P < 0.002), as well as the TDT (P < 0.004), demonstrated an association between autistic disorder and 155CA-2 in these families. Meiotic segregation distortion could be excluded as a possible cause for these results since no disequilibrium was observed in unaffected siblings. These findings support a role for genetic variants within the GABA receptor gene complex in 15q11-13 in autistic disorder.  相似文献   
998.
The purpose of this study was to determine the incidence of Clostridium perfringens-associated vomiting and diarrhea in canine and feline patients at the Okinawa Branch Veterinary Service and to establish a relationship between dietary indiscretion and the presence of clostridial enterotoxemia. Stool samples were obtained from 38 control animals and 44 animals with vomiting and diarrhea during a 3-month period. For each sample, fecal cytology were examined for the presence of C. perfringens, white blood cells, and red blood cells. A survey was also completed by the animal's owner, which provided the researcher with information on the owner's pet feeding practices. After the data were analyzed, 27% of animals with vomiting and diarrhea were found to have C. perfringens upon examination of their fecal samples (p < 0.05), compared with 11% for control animals. Results of our survey revealed that when owners were questioned regarding their feeding practices, 45% of the animals with C. perfringens-positive fecal samples and with clinical signs of vomiting and/or diarrhea had an episode of dietary indiscretion soon before the illness (p < 0.05). Therefore, we conclude that C. perfringens is an important cause of vomiting and diarrhea in our patient population and that a causal relationship may exist between dietary indiscretion and C. perfringens-associated intestinal disease.  相似文献   
999.
Severe aplastic anemia can be treated with either bone marrow transplantation (BMT) or immunosuppressive therapy (IST). A retrospective review of patients with severe aplastic anemia treated with both of these modalities was conducted. Fifteen BMT and 16 IST patients were available for analysis, and follow-up of 22 and 15 years was available for the BMT and IST groups, respectively. Median survival was limited to 4.3 months in BMT patients vs. 135.2 months in IST patients, despite the older median age of the latter (22 vs. 55 years). Actuarial survival at 1 and 5 years was 87% and 78% for the IST patients and 40% and 33% for the BMT patients. Hematologic response rates, as defined by achievement of transfusion independence, were similar for the two groups. Long-term responses and survival are possible with antithymocyte globulin/cyclosporin A.  相似文献   
1000.
The purpose of this study was to determine how oligodendrocytes die following Fas receptor activation. An immortalized human oligodendrocyte hybrid line (MO3.13) was challenged with Fas ligand (FasL), and cell death was assessed by flow cytometry and DNA gel electrophoresis. Caspase activation was determined by either Western immunoblotting on cell extracts or by whole-cell flow cytometry. FasL challenge clearly induced substantial apoptotic cell death in the oligodendrocyte hybrid cell line, as judged by flow cytometry and by the presence of prominent low molecular weight DNA banding patterns after gel electrophoresis. Western immunoblots showed marked increases in cleaved caspase-1, 8, and 3, indicating that the extrinsic Fas death receptor-induced pathway was activated. The intrinsic mitochondrial pathway was also activated, but only at a minimal level. These findings demonstrate that there are several independent molecular sites within the extrinsic caspase cascade in oligodendrocytes where inhibitory compounds may be capable of blocking cell death in vivo.  相似文献   
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