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91.
92.
Background. To evaluate responses of residents to a hematology/oncology rotation.Methods. A self-administered mail survey among internal medicine residents in a university-based training program who were required to complete a hematology/oncology rotation at a comprehensive cancer center.Results. The majority of the residents rated the duration of the rotation as adequate and quality as excellent or good. It had a positive impact on certain knowledge areas, general opinion about hematology/oncology, preparation for board examination, and motivation to pursue this subspecialty, especially among residents who had performed additional electives.Conclusion. A hematology/oncology rotation received a generally positive evaluation from internal medicine residents.  相似文献   
93.
BACKGROUND: Inferior oblique overaction can be either secondary (as a sequela of ipsilateral superior oblique palsy) or primary (commonly associated with horizontal strabismus). Superior oblique underaction often coexists with both primary and secondary inferior oblique overaction. This retrospective case series compares the efficacy of inferior oblique myectomy versus anterior transposition in improving inferior oblique overaction and superior oblique underaction in eyes with either primary or secondary inferior oblique overaction. METHODS: One hundred twenty eyes of 81 patients were included in this retrospective case series, of which 20 had anterior transposition of the inferior oblique and 100 eyes underwent myectomy. Inferior oblique myectomy was compared with inferior oblique anterior transposition in improving inferior oblique overaction and superior oblique underaction in each diagnostic subgroup. Postoperative outcome was qualitatively and quantitatively assessed. Fisher's exact test was used to compare the outcomes. The quantitative improvement of function in terms of inferior oblique overaction and superior oblique underaction was analyzed by regression analysis. RESULTS: When postoperative inferior oblique overaction was considered, there was no statistically significant difference between myectomy and anterior transposition in both primary and secondary inferior oblique overaction. Myectomy was superior to anterior transposition in improving superior oblique underaction in both primary inferior oblique overaction (OR = 0.14; 95% CI, 0.015-1.45; p = 0.056) and secondary inferior oblique overaction (OR = 0; 95% CI, 0-0.027; p < 0.001). The quantitative improvement of function showed a significant difference between procedures for superior oblique underaction (t-test; p = 0.005; 95% CI, 0.25-1.3) but not inferior oblique overaction (t-test; p = 0.8; 95% CI, -0.67-0.54). CONCLUSIONS: This study demonstrates both inferior oblique myectomy and inferior oblique anterior transposition to be effective in correcting primary and secondary inferior oblique overaction. Myectomy is more effective in improving superior oblique underaction associated with both primary and secondary inferior oblique overaction. On this basis, we feel that inferior oblique myectomy has some advantage over anterior transposition in treating combined inferior oblique overaction and superior oblique underaction and can be considered the procedure of choice.  相似文献   
94.
The myelodysplastic syndrome (MDS) represents a group of clonal hematological disorders characterized by progressive cytopenia reflecting defects in erythroid, myeloid and mega karyocytic maturation. The incidence of MDS is greter in older age groups. Detailed studies on MDS from India are not available. Cytogenetic study using GTG-banding and FISH revealed 54.5% clonal chromosomal abnormalities. We have carried out chromosomal breakage study from peripheral blood cultures induced with mitomycin C, in karyotypically normal MDS (49) and 15 (30.6%) showed significant (p < 0.001) increase in chromosome damage compared to controls. Among 22 occupationally exposed MDS, 6 (27.3%) showed a high frequency of chromosome breakage while in the non-exposure (n=27) group, high chromosome breakage was noted in 9 (33.3% ) MDS patients. Our results suggest that the high chromosome damage may be due to acquired Fanconi anemia which leads to multiple defects in chromosomes and clonal chromosome anomalies.  相似文献   
95.
Orbital hydatid disease is rare, even in endemic areas. We present a case of disseminated hydatid disease involving the orbit, spleen, lung and liver in a lady aged 35 years. Based on a typical clinical presentation, presence of eosinophilia, a positive indirect haemagglutination test for hydatid disease and presence of similar disseminated, anechoic cystic masses in the liver, lung, spleen and orbit on imaging studies, the diagnosis of hydatid cyst was seriously considered before surgery. Aspiration of the cyst, followed by cryo-extraction of the cyst wall through transconjunctival route was safely performed. Histopathological examination confirmed the diagnosis. In conclusion, multisystemic involvement of liver, lung and spleen in a case of orbital hydatid cyst has never been reported before. The surgical technique adopted in this case is safe and effective.  相似文献   
96.
Neurofibroma is an extremely rare neural tumor of the lacrimal sac. We present a case of neurofibroma of the lacrimal sac in a 45-year-old lady. Based on the history of intermittent epiphora, presence of a mass in the lacrimal sac region, dacryocystogram suggestive of space occupying lesion within the lacrimal sac and computed tomographic image of a tumor lying in the lacrimal fossa region, a tentative diagnosis of lacrimal sac neoplasm was made. Excision of the tumor with repair of the lacrimal sac was performed. Histopathology proved it to be neurofibroma of the lacrimal sac. Until now, only four cases have been reported worldwide. The paucity of reported cases limits our knowledge regarding the natural course, treatment, results and prognosis of this tumor.  相似文献   
97.
Dry and 24 h imbibed rapeseeds and sesame seeds were defatted with hexane and the resulting freeze-dried powder was analysed for the functional properties of the meals. Water absorption capacity (WAC) of imbibed rapeseed meal and fat absorption capacity (FAC) of both the imbeded meals were higher than those for dry meals. Protein solubility of rapeseed meals was improved by imbibition and both the imbibed meals exhibited maximum protein solubility at pH 12. Rapeseed meal possessed better foaming properties and viscosity than sesame seed meal. Imbibition considerably enhanced the foaming properties of rapeseed meal while the emulsification properties and viscosity did not change appreciably. Emulsification properties of sesame meal were higher than rapeseed meal.  相似文献   
98.
BACKGROUND: Global health care costs in Canada and the United States have been examined on a macroeconomic level. However, to our knowledge, comparative costs of specific procedures in the 2 countries have not been closely studied. METHODS: To perform a microeconomic comparison of costs of open abdominal aortic aneurysm (AAA) repair, we examined the costs of treating 1057 consecutive patients from 4 Canadian (n = 552) and 6 US (n = 505) hospitals. Participating hospitals used the same cost accounting system that provided demographic, clinical, and cost data (excluding physician's fees) for each patient. Canadian dollar costs were converted to US dollar costs using purchasing power parities. RESULTS: Compared with patients who underwent AAA repair in the United States, Canadian patients were significantly younger (mean +/- SD, 70.2 +/- 10.5 vs 73.3 +/- 8.5 years; P<.001) and were less likely to undergo elective repair (48.5% vs 73.3%; P<.001). The median length of hospital stay was longer in Canada (9.0 vs 7.0 days; P<.001), and mortality rates were similar (12.0% [Canada] vs 9.9% [United States]; P =.29). The mean +/- SEM cost of AAA repair was dollars 15 852 +/- dollars 790 in Canada compared with US dollars 23299 +/- US dollars 1410 in the United States. CONCLUSIONS: The cost of AAA repair is substantially higher in the United States compared with Canada, despite shorter lengths of stay and similar clinical outcomes. The difference in total treatment costs between Canadian and American hospitals was partially attributable to differences in direct costs, but was largely due to differences in overhead costs.  相似文献   
99.
We examined whether early maternal separation influenced the susceptibility to behavioural sensitization produced by repeated intravenous (i.v.) injections of cocaine in adult female rats. For the first 21 days of life litters were separated from their mother for either 15 min (MS-15) or 180 min/day (MS-180). Control animals were subjected only to regular cage changes (animal facility reared; AFR). In adulthood, these three groups did not differ in their locomotor response to placement in a novel environment or to an acute i.v. injection of cocaine. After six additional daily injections of either saline or cocaine and following a 7-day drug-free interval, sensitization was assessed by giving all rats a challenge i.v. injection of cocaine. Rats exposed to either period of maternal separation (MS-15 or MS-180) showed significantly less robust sensitization than AFR rats. Therefore, early maternal separation decreased susceptibility to behavioural sensitization produced by cocaine in adulthood and the specific duration of maternal separation had no effect on this outcome.  相似文献   
100.
Chronic stress and obesity: a new view of "comfort food"   总被引:6,自引:0,他引:6       下载免费PDF全文
The effects of adrenal corticosteroids on subsequent adrenocorticotropin secretion are complex. Acutely (within hours), glucocorticoids (GCs) directly inhibit further activity in the hypothalamo-pituitary-adrenal axis, but the chronic actions (across days) of these steroids on brain are directly excitatory. Chronically high concentrations of GCs act in three ways that are functionally congruent. (i) GCs increase the expression of corticotropin-releasing factor (CRF) mRNA in the central nucleus of the amygdala, a critical node in the emotional brain. CRF enables recruitment of a chronic stress-response network. (ii) GCs increase the salience of pleasurable or compulsive activities (ingesting sucrose, fat, and drugs, or wheel-running). This motivates ingestion of "comfort food." (iii) GCs act systemically to increase abdominal fat depots. This allows an increased signal of abdominal energy stores to inhibit catecholamines in the brainstem and CRF expression in hypothalamic neurons regulating adrenocorticotropin. Chronic stress, together with high GC concentrations, usually decreases body weight gain in rats; by contrast, in stressed or depressed humans chronic stress induces either increased comfort food intake and body weight gain or decreased intake and body weight loss. Comfort food ingestion that produces abdominal obesity, decreases CRF mRNA in the hypothalamus of rats. Depressed people who overeat have decreased cerebrospinal CRF, catecholamine concentrations, and hypothalamo-pituitary-adrenal activity. We propose that people eat comfort food in an attempt to reduce the activity in the chronic stress-response network with its attendant anxiety. These mechanisms, determined in rats, may explain some of the epidemic of obesity occurring in our society.  相似文献   
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