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For physicians to better treat and advise their patients on the roles of behavioral and social factors in health and disease, greater levels of competency in social and behavioral sciences are needed. Physicians should also understand the structure, financing, and administration of the health care delivery system, so that they will be able to practice medicine effectively and participate in planning and managing the delivery of care. And, improving overall public health requires that physicians understand the basic tenets of population-based medicine. One way to achieve these goals is to develop education and training programs for integrating formal public health training with formal medical training.There are many models by which a medical student or practitioner can obtain a master of public health (MPH) degree. In this article, the authors describe an accelerated one-year MPH program for competitively selected New York City medical students who have completed their third year of training and enroll at the Mailman School of Public Health, Columbia University. The Macy Scholars Program, offered between 1999 and 2007 to 12 students per year, is completed between the third and fourth years of medical school. Under full-tuition scholarships, students complete a practicum experience, attend seminars, and write a master-level paper or thesis, among other requirements. Data from an evaluation of this program demonstrate participant satisfaction and support of the program, outstanding academic performance, and the effect of public health training on their residency and career choices.  相似文献   
84.
The human epidermal growth factor receptor (HER) family of receptor tyrosine kinase has been extensively studied in breast cancer; however, systematic studies of EGFR gene amplification and protein overexpression in breast carcinoma are lacking. We studied EGFR gene amplification by chromogenic in situ hybridization (CISH) and protein expression by immunohistochemistry in 175 breast carcinomas, using tissue microarrays. Tumors with >5 EGFR gene copies per nucleus were interpreted as positive for gene amplification. Protein overexpression was scored according to standardized criteria originally developed for HER-2. EGFR mRNA levels, as measured by Affymetrix U133 Gene Chip microarray hybridization, were available in 63 of these tumors. HER-2 gene amplification by fluorescence in situ hybridization (FISH) and protein overexpression by immunohistochemistry were also studied. EGFR gene amplification (copy number range: 7-18; median: 12) was detected in 11/175 (6%) tumors, and protein overexpression was found in 13/175 (7%) tumors. Of the 11 tumors, 10 (91%) with gene amplification also showed EGFR protein overexpression (2+ or 3+ by immunohistochemistry). The EGFR mRNA level, based on Affymetrix U133 chip hybridization data, was increased relative to other breast cancer samples in three of the five tumors showing gene amplification. Exons 19 and 21 of EGFR, the sites of hotspot mutations in lung adenocarcinomas, were screened in the 11 EGFR-amplified tumors but no mutations were found. Three of these 11 tumors also showed HER-2 overexpression and gene amplification. Approximately 6% of breast carcinomas show EGFR amplification with EGFR protein overexpression and may be candidates for trials of EGFR-targeted antibodies or small inhibitory molecules.  相似文献   
85.
Orally induced tolerance is a physiologically relevant form of peripheral tolerance, which is believed to be important for the prevention of pathological immune responses in the gut. Of several mechanisms proposed to mediate oral tolerance, one that has received much attention recently is the concept of regulatory CD4+ T cells. As recent studies have suggested that interleukin (IL)-15 may be important for the differentiation and maintenance of regulatory CD4+ T cells, we have examined the role of IL-15 in oral tolerance, using a soluble form of the IL-15 receptor (sIL-15R) which blocks the biological effects of IL-15 in vivo. Oral tolerance induced by feeding mice ovalbumin (OVA) in a low-dose regimen believed to induce regulatory T cell activity was not affected by the administration of sIL-15R during either the induction or maintenance phase of tolerance. Thus, oral tolerance does not involve an IL-15-dependent mechanism.  相似文献   
86.
BACKGROUND: A self-rating inventory has been developed to measure DSM-IV and ICD-10 diagnoses of major (moderate to severe) depression by the patients' self-reported symptoms. This Major Depression Inventory (MDI) can be scored both according to the DSM-IV and the ICD-10 algorithms for depressive symptomatology and according to severity scales by the simple total sum of the items. METHODS: The Schedule for Clinical Assessment in Neuropsychiatry (SCAN) was used as index of validity for the clinician's DSM-IV and ICD-10 diagnosis of major (moderate to severe) depression. The sensitivity and specificity of MDI was assessed in a sample of 43 subjects covering a spectrum of depressive symptoms. RESULTS: The sensitivity of the MDI algorithms for major depression varied between 0.86 and 0.92. The specificity varied between 0.82 and 0.86. When using the total score of MDI the optimal cut-off score was estimated 26 and the total score was shown to be a sufficient statistic. LIMITATIONS: The sample of subjects was limited. Patients with psychotic depression were not included. CONCLUSION: The MDI was found to have a sensitivity and specificity which is acceptable. The questionnaire is brief and can be scored diagnostically by the DSM-IV and ICD-10 algorithms as well as by its simple total score.  相似文献   
87.
Nepetalactone, the primary component of catnip oil, was compared with the repellent N,N-diethyl-3-methylbenzamide (deet) for its ability to affect the host-seeking ability of Aedes aegypti (L.). A triple cage olfactometer was used to bioassay each substance and to assess its attraction inhibition (spatial repellent) attributes when combined with the following attractants: carbon dioxide, acetone, a blend of L-lactic acid and acetone, and human odors. Repellent tests were conducted with each substance against female Ae. aegypti, Anopheles albimanus Weidemann, and Anopheles quadrimaculatus Say. Catnip oil and deet were both weakly attractive to Ae. aegypti, catnip oil was the better spatial repellent, whereas deet was a more effective contact repellent in tests with all three species of mosquitoes.  相似文献   
88.
AIM: We tested the hypothesis that oxytocin in normal man causes natriuresis by means of nitric oxide and/or atrial natriuretic peptide. METHODS: Normal male subjects were investigated after 4 days of sodium controlled diets (30 mmol sodium chloride day(-1), n = 8 or 230 mmol sodium chloride day(-1), n = 6). Oxytocin was infused intravenously (1 pmol kg(-1) min(-1) for 240 min). RESULTS: Mean arterial blood pressure, heart rate and glomerular filtration rate by clearance of chromium-labelled ethylenediaminetetraacetate remained stable. Plasma oxytocin increased from 2 to 3 pg mL(-1) to around 50 pg mL(-1). Oxytocin decreased urine flow (4.2 +/- 0.2--0.75 +/- 0.11 and 4.6 +/- 1.3-1.4 +/- 0.6 mL min(-1), low- and high-salt diet, respectively). During low-salt conditions, oxytocin reduced sodium and potassium excretion (11 +/- 2--4 +/- 2 and 93 +/- 19--42 +/- 3 micromol min(-1), respectively). Plasma renin, angiotensin II, aldosterone and renal excretion of metabolites of nitric oxide (nitrate and nitrite) all decreased. Plasma atrial natriuretic peptide and cyclic guanosine monophosphate were unchanged. A similar pattern was obtained during high-salt conditions but in this case the antinatriuresis was not different from that occurring during the corresponding time control series. CONCLUSIONS: The data reject the hypothesis. In contrast, we found significant antinatriuretic, antikaliuretic and antidiuretic effects, which were not mediated by the renin-angiotensin-aldosterone system, atrial natriuretic peptide, systemic haemodynamics, or processes increasing urinary excretion of metabolites of nitric oxide. The natriuretic effect of oxytocin found in laboratory animals is species-specific.  相似文献   
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90.
The effect of ellagic acid and some of its more lipophilk derivativeson the mutagenicity of (? )-7ß, 8-di-hydroxy-9 10-epoxy-7,8, 910-etrahydrobenz[a]pyrene was examined in Salmonella typhimuriumTA100. Ellagic acid, 3, 3' -di-O-methylellagic add, 4, 4' -di-O-methylellagicacid and 3-O-decyiellagic acid were found to have approximatelyequal antimutagenic activity. The tissue distribution and eliminationof ellagic add, 3, 3' -di-O-methyleCagic add and 3-O-decylellagicacid were examined in CD-I mice. Little or no ellagic acid (<1 nmol/g) was found in blood, lung or liver after the oral administrationby gavage of 300 µunol of ellagic acid per kg body weightor after feeding 1% of ellagic acid in the diet for 1 week.Following the i.p. administration of 120 µmol/kg of ellagicacid, the blood and lung levels of ellagic acid were 15–20nmol/g at 30 min after the dose, and the concentrations of ellagicacid decreased to 1–3 nmol/g at 6–8 h after thedose. A portion of the administered i.p. dose precipitated inthe abdominal cavity. After i.v. administration, ellagic acidwas eliminated very rapidly from blood, lung and liver, and 70% of the administered dose was recovered in the urine andfeces as free ellagic acid and its conjugates. At 2 h afteran i.v. injection of 60 µ/kg of ellagic add, 46% of thedose was recovered in the urine as ellagic acid and its conjugates.Of this amount, about half was excreted as free ellagic acidand half was excreted as conjugates. An additional 25% of thedose was recovered in the feces (mostly as free ellagic acid)after 7 h. The disposition of 3, 3' -di-O-methylelIagic acidor 3–O-decyIellagic acid after i.v. administration (32µmol;sol;kg) was examined and compared to the dispositionof the same i.v. dose of ellagic acid. The concentrations ofellagic acid, 3,3' -di-O-methylellagic acid and 3-O-decytellagicadd decreased rapidly in the blood, liver and lung, but theconcentrations of 3-O-decylellagic add in the lung throughoutthe experimental period (2–360 min) was on average 20-to 40-fold higher than the corresponding average concentrationsof ellagic acid or 3, 3' -di-O-methylellagic acid.  相似文献   
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