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11.
Air embolization is an unusual but potentially dangerous complication in left heart catheterization. Microbubbles can be detected with two-dimensional echocardiography, which is often used for this purpose during open heart and bypass surgeries. Permanent neurologic sequelae and hemodynamic collapse can result from embolization of air bubbles to the cerebral and coronary circulations, respectively. Hyperbaric oxygen is the treatment of choice for cerebral air embolization. We present a 39-year-old man who had air embolization during left ventriculography in the form of a large pocket of "pooled" air. The patient was treated with conservative therapy successfully. Two-dimensional transthoracic echocardiography was used to document the presence of the air and follow its dissolution. 相似文献
12.
MC Doherty RS Garfein D Vlahov B Junge PJ Rathouz N Galai JC Anthony P Beilenson 《Canadian Metallurgical Quarterly》1997,145(8):730-737
This study examines the effect of a Needle Exchange Program (NEP) on the quantity and geographic distribution of discarded needles on the streets of Baltimore, Maryland, and presents methods to survey discarded needles in the community. A random sample of 32 city blocks located within high-drug-use census tracts, stratified by east and west sides of the city and by proximity to the NEP, was selected for survey. Three teams surveyed the number of needles and the number of drug vials and unbroken glass bottles ("trash") to control for practice effects. Surveillance was conducted prior to initiation of the NEP in August 1994 and 1 and 2 months thereafter. Over the three study periods, the absolute count of discarded needles was 106, 130, and 128, respectively; the number of vials and bottles was 3,048, 3,825, and 3,796, respectively. The initial nonstatistically significant increase in needles (mean change = 0.38, 95% confidence interval (CI) -0.18 to 0.93) was offset by accounting for background trash. Regression models fitted with the generalized estimating equation method, which accounted for within-block correlation over time, showed no significant increase in the number of needles after adjustment for trash during the first 2 months of the NEP's operation. These data suggest that the initiation of NEPs does not result in an increase in the number of discarded needles on the street. 相似文献
13.
JC Weber 《Canadian Metallurgical Quarterly》1998,19(12):924-927
INTRODUCTION: Medical practice has to move from a one-on-one relationship to consensual organization of the overall management of patients. Issues at stakes and potential consequences following such changes are discussed. EXEGESIS: The evolution of medical practice is introduced as a necessity resulting from both improvements in medical technology and economical pressure. Utilitarian and procedural doctrines are promoted, taking the place of ethical bases. The one-on-one relationship evidences two essential aspects: there is often more in the request made to the practitioner than just the expression of an immediate need, and the patient is not only an organism. Both aspects reflect the specificity of human beings. There is a danger that they will disappear, as they are not included in the definition of "useful", which in fact controls current choices. CONCLUSION: Medical practice is radically modifying its own basis. Practitioners who acknowledge these changes should be aware of their cost. 相似文献
14.
Several irreversible inhibitors of monoamine oxidase B, can promote survival of damaged neurons in several animal models of cerebral injury. Today it is evident that this effect is not a consequence of monoamine inhibition. Instead it has been proposed that L-deprenyl may act via an unrelated non-monoamine oxidase type- of binding site. In the present study we have investigated if brain tissue from MAOB knockout mice contain such "non-MAO" binding sites for radiolabelled deprenyl. Interestingly, no binding of L-deprenyl was observed indicating that the mother compound does not act directly via a macromolecular target. This is enticing since several alternative mechanisms of action have been proposed in the literature. 相似文献
15.
P Ruffié M Lehmann F Galateau-Sallé JL Lagrange JC Pairon 《Canadian Metallurgical Quarterly》1998,85(6):545-561
The "Standards, Options and Recommandations" (SOR), started in 1993, are a collaborative project between the Federation of the French Cancer Centres (FNCLCC), the 20 French Cancer Centres and specialists from French Public Universities, General Hospitals and Private Clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and outcomes for cancer patients. The methodology is based on literature review and critical appraisal by a multidisciplinary experts group, with feedback from specialists in cancer care delivery. The objectives are to develop a clinical practice guideline with definitions of Standards. Options and Recommendations for the clinical care of malignant pleural mesothelioma. Data have been identified by literature search using Medline (1966-June 1997) and personal references lists. The main criteria considered were incidence, risk factors, pronostic factors and efficacy of cancer treatment. Once the guideline was defined, the document was submitted to 40 independent reviewers for peer review, and to the medical committees of the 20 French Cancer Centres for review and agreement. The results are: 1) systematic assessment of (professional) exposure to asbestos is based on a standardized interrogatory, completed by specific consultation for professional disease; 2) diagnostic and clinical staging is based on multiple biopsies under thoracoscopy and thoracic scanner; 3) there is no indication for extemporaneous examination, immunocytochemistry should use cytokeratine, EMA, vimentine, ACE, Leu-M1; 4) clinical care: the recommended staging classification is the IMIG (International Mesothelioma Interest Group) classification; 5) validated, independent pronostic factors are stage of disease patient's functional status and histologic type (i.e. epithelial lesions are of better prognosis); 6) treatment is based on symptomatic and palliative treatment options. Anticancer treatments (surgery, chemotherapy, immunotherapy, radiotherapy) did not show significant improvement of survival. The inclusion of patients in clinical trials is recommended. 相似文献
16.
Whereas most liver resections can be performed within 60 min, the period of vascular clamping and resulting ischemia may prove too short to allow complex major liver resections (MLR) especially on diseased livers. To overcome this problem, cooling of the liver with 4 degrees C preservations solution routinely used in liver transplantation may be used in three different approaches to MLR: I "In situ": the liver remains in the abdomen and integrity of afferent and efferent vessels is conserved. II "Ex situ-in vivo": the liver exteriorized from the abdomen by transecting all hepatic veins, remains connected to the porta hepatis. III "Ex vivo": the liver being removed from the abdomen, the MLR is performed extracorporeally. Of 15 MLR reported here, 11 were performed "in situ" and 4 "ex situ-in vivo"/Nowadays, the liver surgeon's "toolbox" must contain hypothermic liver perfusion. In carefully selected cases, these techniques allow MLR on diseases livers or mandating complex vascular procedures. 相似文献
17.
JC Lovejoy 《Canadian Metallurgical Quarterly》1998,7(10):1247-1256
Women have a higher prevalence of obesity than men in most developed countries. Obesity affects many aspects of women's health by increasing risk for heart disease, diabetes, breast cancer, and infertility. One reason for the gender difference in obesity may be that fluctuations in reproductive hormone concentrations throughout women's lives uniquely predispose them to excess weight gain. Studies in experimental animals and women have shown that hormonal changes across the menstrual cycle affect calorie and macronutrient intake and alter 24-hour energy expenditure. Pregnancy is a significant factor in the development of obesity for many women. Various factors are associated with excess weight retention following pregnancy, including weight gain during pregnancy, ethnicity, dietary patterns, and interval between pregnancies. There is a need to tailor recommendations for energy intake during pregnancy to individual women, and recent evidence also suggests that the timing of weight gain during pregnancy is a critical factor. Menopause is also a high-risk time for weight gain in women. Although the average woman gains 2-5 pounds during menopausal transition, some women are at risk for greater weight gains. There is also a hormonally driven shift in body fat distribution from peripheral to abdominal at menopause, which may increase health risks in older women. Hormone therapies have varying impacts on body weight and fat distribution. In summary, hormonal fluctuations across the female life span may explain the increased risk for obesity in women. Awareness of these factors allows development of targets for prevention and early intervention. 相似文献
18.
While loss-of-function mutations in Gsalpha are invariably associated with the short stature and brachydactyly of Albright hereditary osteodystrophy (AHO), the association with hormone resistance (to parathyroid hormone and thyrotropin) typical of pseudohypoparathyroidism type Ia (PHP-Ia) is much more variable. Observational studies and DNA polymorphism analysis suggest that maternal transmission of the Gsalpha mutation may be required for full expression of clinical hormone resistance. To test this hypothesis, we studied transmission of a frameshift mutation in Gsalpha through three generations of a pedigree affected by AHO and PHP-Ia. While all family members carrying this loss-of-function mutation in one Gsalpha allele had AHO, neither the presence of the mutation nor the degree of reduction of erythrocyte Gsalpha bioactivity allowed prediction of phenotype (AHO alone versus AHO and PHP-Ia). Paternal transmission of the mutation (from the patriarch of the first generation to three members of the second generation) was not associated with concurrent PHP-Ia, but maternal transmission (from two women in the second generation to four children in the third generation) was invariably associated with PHP-Ia. No expansion of an upstream short CCG nucleotide repeat region was detected, nor was there evidence of uniparental disomy by polymorphism analysis. This report, the first to document the effects across three generations of both paternal and maternal transmission of a specific Gsalpha mutation, strongly supports the hypothesis that a maternal factor determines full expression of Gsalpha dysfunction as PHP-Ia. 相似文献
19.
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