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91.
Osteocalcin and matrix Gla protein (MGP) are two vitamin K-dependent proteins present in bone and cartilage. Transgenic mice models were recently developed to isolate the function of each of these proteins. While osteocalcin-deficient mice have increased bone formation, MGP-deficient mice have abnormal calcification leading to osteopenia, fractures, and premature death owing to arterial calcification.  相似文献   
92.
Primary dystonia is a disorder of movement for which no consistent pathophysiology has been identified; in the absence of evidence to the contrary, it is assumed to be cognitively benign. We have studied a clinically heterogeneous group of 14 patients with primary dystonia on a battery of neuropsychological tests. Despite well-preserved speed of information processing, language, spatial, memory and general intellectual skills relative to normal controls, we have identified a constellation of attentional-executive cognitive deficits on the Cambridge Neuropsychological Test Automated Battery (CANTAB). Specifically, patients demonstrated significant difficulties negotiating the extra-dimensional set-shifting phase of the IED task. The implications of these findings for the pathophysiology of primary dystonia are discussed. This is, to the best of our knowledge, the first report of a significant cognitive deficit in patients with primary dystonia.  相似文献   
93.
The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.  相似文献   
94.
In the last century, both the health and life expectancy of Americans improved dramatically. These gains were primarily the result of advances in public health. But the approaches used may not be adequate to achieve the next level of improvements in health. Because health exists in the context of social, environmental, community, religious, political, and other spheres, ecological approaches that incorporate behavioral and social science theory and methodologies may provide the best avenue for advancing health in the 21st century. In 1999, the New York City Department of Health (NYCDOH) undertook the task of integrating behavioral and social science into its public health practice. The experience serves as a case study on the integration process at a public health agency.  相似文献   
95.
PURPOSE: Perillyl alcohol (POH) displays preventive and therapeutic activity against a wide variety of tumor models, and it has been suggested that this might be associated with the ability of POH to interfere with Ras prenylation. POH also selectively induces G(1) arrest and apoptosis in Bcr/Abl-transformed hematopoietic cells. Because signaling through Ras is necessary for Bcr/Abl transformation, we examined whether POH induces its anti-leukemia effect by inhibiting Ras signaling. EXPERIMENTAL DESIGN: The ability of POH to inhibit posttranslational farnesylation and signaling from Ras as well as signaling through the Raf-Mek-Erk cascade was examined in Bcr/Abl-transformed and mock-transformed cells and related to the anti-leukemia effect of POH. RESULTS: POH does not affect Ras prenylation or Ras activity, but it blocks signaling downstream of Ras by reversing the state of activation of the Erk kinase, Mek. POH affects Mek activity only when it is added to intact cells. Treatment of either cell lysates or of purified Mek with POH has no effect on Mek activity. Inhibition of the Mek-Erk pathway seems to be related to the POH anti-leukemia effect for the following reasons: (a) the concentration of POH needed to block the Erk pathway, as well the kinetics with which POH inhibits this signaling cascade, both correlate with the anti-leukemia effect of POH; (b) both U0126 (a specific Mek inhibitor) and POH induce similar anti-leukemia effects; and (c) mock-transformed hematopoietic cells are simultaneously resistant to POH anti-leukemia effects and inhibition of the Mek-Erk pathway. CONCLUSION: Blocking Mek is sufficient to induce growth arrest and apoptosis in Bcr/Abl-transformed cells; therefore, POH represents a novel small molecule inhibitor of Mek that might be effective for treating Bcr/Abl leukemias.  相似文献   
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97.
OBJECTIVES: Despite longstanding national guidelines, many children with asthma do not receive annual influenza vaccinations. Information from Medicaid-administrative claims data was integrated into the Michigan Care Improvement Registry (MCIR) to prompt providers regarding influenza vaccination among children with high-risk conditions such as asthma. The attitudes of pediatric primary care providers regarding the implementation of this system were assessed. METHODS: A survey was sent in February 2006 to office-based general pediatricians (n = 300) and family physicians (n = 300) in Michigan. The survey focused on influenza vaccination during the 2005-2006 influenza season and attitudes regarding a reminder system for providers using the MCIR. RESULTS: Overall response rate was 67 percent. MCIR participation was high (91%) among respondents, and most (83%) had MCIR information available to them prior to visits with pediatric patients. Most physicians (75%) considered the MCIR high-risk indicator for influenza vaccination a feature that they would find helpful. Some respondents reported concerns that the reminder system is limited to Medicaid patients only (44%) and regarding the completeness of Medicaid data to identify children with asthma (24%). CONCLUSIONS: Physicians have a positive overall view of a statewide registry-based automated reminder system to assist in identifying children with asthma for influenza vaccination, albeit with specific areas of concern.  相似文献   
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Changes in plasma insulin and glucose concentrations before and after feeding were measured in six female subjects (post-obese) who had regained a normal body mass after a history of severe obesity (mean weight loss, 37.1 +/- 2.6 kg). The responses of the post-obese group were compared with a group of weight- and age-matched subjects who had not been obese (lean). After an overnight fast subjects were fed a meal at 09.00 h and 13.10 h. Fasting and post-prandial insulin concentrations were lower in post-obese than in lean subjects. Immediately after beginning to eat at 13.10 h all subjects showed a rise in insulin concentration with no change in glucose concentration. In this pre-absorptive period there was no significant difference in insulin concentration between post-obese and lean subjects, although the increment in insulin concentration over baseline values was greater in post-obese subjects (P less than 0.05). It is concluded that abnormalities of insulin secretion and action remain after weight loss by obese subjects. These abnormalities may predispose to hyperphagia and accumulation of excess adiposity.  相似文献   
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