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991.
The production of biochemical markers associated with the osteoblastic phenotype, and accompanying changes in the expression of voltage-operated Ca2+ channels, have been examined in rat bone marrow stromal cell cultures treated with dexamethasone (10-8 M). Whole cell clamp analysis of voltage-operated Ca2+ channels in control cultures (using Ba2+ as the charge carrier) revealed primarily a high voltage-activated (HVA), slowly inactivating current, which was enhanced two- to threefold by treatment of the cells with Bay K 8644 (300 nM) and inhibited by nifedipine (4 M). In dexamethasone-treated cultures, the I–V relationship for inward current was shifted to more positive potentials in comparison with control cells. Most cells in these cultures possessed both the HVA current and also a faster inactivating, low-voltage-activated (LVA), nifedepineresistant current. These two currents could be separated both by nifedipine and by the use of steady state inactivation of the LVA current. The two components of the Ba2+ current varied widely in their relative size. The combination of LVA and HVA currents seen in dex-induced stromal cells resembles records of voltage-operated Ca2+ channels from cultures of calvarial osteoblasts. 相似文献
992.
INTRODUCTION: Patients transported by helicopter often require advanced airway management. The purpose of this study was to determine whether or not the in-flight environment of air medical transport in a BO-105 helicopter impairs the ability of flight nurses to perform oral endotracheal intubation. SETTING: The study was conducted in an MBB BO-105 helicopter. METHODS: Flight nurses performed three manikin intubations in each of the two study environments: on an emergency department stretcher and in-flight in the BO-105 helicopter. RESULTS: The mean time required for in-flight intubation (25.9 +/- 10.9 seconds) was significantly longer than the corresponding time (13.2 +/- 2.8 seconds) required for intubation in the control setting (ANOVA, F = 38.7, p < .001). All intubations performed in the control setting were placed correctly in the trachea; there were two (6.7%) esophageal intubations in the in-flight setting. The difference in appropriate endotracheal intubation between the two settings was not significant (chi 2 = 0.3; p > 0.05). CONCLUSION: Oral endotracheal intubation in the in-flight setting of the BO-105 helicopter takes approximately twice as long as intubation in a ground setting. The results support pre-flight intubation of patients who appear likely to require urgent intubation during air medical transport in the BO-105 helicopter. 相似文献
993.
Gerald P. Marquette Thomas Mechas Jean Charest J. Evelyne Rey 《Journal canadien d'anesthésie》1994,41(11):1053-1056
This prospective study was completed to determine the influence of epidural anaesthesia on the fetoplacental circulation of
normal subjects. Thirty-seven normal pregnant patients at term, undergoing elective Caesarean section, had Doppler measurements
of the fetal umbilical artery blood flow velocity before and after epidural anaesthesia using lidocaine 2% without epinephrine.
There were no differences in systolic/diastolic, resistance or pulsality indices following epidural anaesthesia. These results
suggest that this technique has no adverse effect on fetoplacental circulation in normal non-labouring subjects.
Cette étude prospective a pour but de déterminer l’influence de l’anesthésie épidurale sur la circulation foeto-placentaire
dans le contexte d’une grossesse normale. Des indices de vélocité du flot de l’artère ombilicale foetale ont été mesurés par
Doppler chez trentesept patientes gravides à terme, sans complications, programmées pour une césarienne élective, avant et
après une anesthèsie épidurale utilisant la lidocaine 2% sans épinéphrine. Les indices de rapport systole/diastole, de résistance
et de pulsatilité sont demeurés inchangés après l’induction de l’anesthésie épidurale. Ces constatations suggèrent que l’anesthésie
épidurale n’a pas d’influence sur la circulation foetoplacentaire chez des patientes enceintes normales à terme qui ne sont
pas en travail. 相似文献
994.
Aidonopoulos AP Papavramidis ST Zaraboukas TG Habib HW Pothoulakis IG 《Obesity surgery》1994,4(1):8-12
Morbidly obese patients constitute a high risk group for the development of gallbladder disease. In our series 70 consecutive
patients underwent vertical gastroplasty in an effort to manage morbid obesity. The mean age was 37 years (range 20-60), and
the mean excess body weight was 92 kg (range 52-265). Six patients (8.5%) had undergone cholecystectomy before bariatric surgery
because of symptomatic cholelithiasis. The remaining 64 patients underwent cholecystectomy at the time of vertical gastroplasty.
Ninety-seven percent of the removed gallbladders had gross or histologic abnormalities, including cholelithiasis 18.5% (13
patients), and cholesterolosis 31% (22 patients). Histologically, chronic cholecystitis was present in all patients with cholelithiasis
and cholesterolosis. Chronic cholecystitis alone was found in 27 patients (38.5%) and only two patients (3%) had normal findings.
The mean excess body weight of the patients with cholesterolosis (96 kg) was not significantly greater than that of patients
with cholelithiasis (89 kg) or chronic cholecystitis (88 kg). Our findings suggest that cholecystectomy should be performed
in all morbidly obese patients concomitant with vertical gastroplasty. 相似文献
995.
996.
Age-related differences in breast cancer treatment 总被引:3,自引:0,他引:3
Background: More than half of the cases of breast cancer treated in the United States occur in women over age 65. This study investigates age-related differences in breast cancer therapy.
Methods: A retrospective review of all women with primary operable invasive breast cancer treated at the University of Michigan Breast Care Center over a 30-month period showed a total of 77 older patients aged 65 years (median, 71; oldest patient, 92) for whom full information was available regarding comorbidity, tumor stage and histology, and details of surgery, radiation, and chemohormonal therapy and complications. Fifty-one similar younger patients aged 55–64 years (median, 59) were identified for comparison. Patients were classified as either having received standard treatment or nonstandard treatment. Standard therapy was prospectively defined as follows: local/regional—lumpectomy and axillary lymph node dissection plus radiation therapy or modified radical mastectomy; systemic—chemotherapy and/or tamoxifen for stage II disease. A comorbidity score calculated for each patient assigned one point each for nursing home residence, nonambulatory status, recent surgery, and each medical problem requiring drug therapy.
Results: When overall treatment (local/regional plus systemic) was assessed, proportionately fewer older patients (55 of 77 versus 47 of 51;p<0.01) received standard treatment. Fewer older than younger patients (62 of 77 versus 50 of 51;p<0.01) received surgical therapy that included an axillary dissection. A smaller proportion of older patients received radiation therapy following lumpectomy and axillary lymph node dissection (26 of 29 versus 19 of 19; N.S.). Overall, only 59 of 77 older patients versus 50 of 51 younger patients (p<0.001) received standard local/regional care. Similar proportions of younger and older patients (19 of 22 and 24 of 30, respectively) received standard systemic therapy for stage II breast cancer, but older patients were less likely to receive chemotherapy than younger patients (7% versus 50%;p<0.001). Treatment-related complications were not age-related but were more frequent in patients receiving standard treatment than in patients receiving nonstandard treatment (45 of 102 versus two of 26;p<0.001). Comorbidity score correlated with the use of nonstandard therapy but not with age. The scores for both older and younger patients receiving overall standard treatment were 0.8 versus 1.5 and 1.4, respectively, in patients receiving nonstandard treatment. Interestingly, explanations for decisions to deviate from standard treatment guidelines were often not identified. Comorbidity was explicitly noted in only one of four younger patients who received nonstandard treatment therapy. In 22 older patients who received nonstandard treatment, comorbidity was cited in eight cases, patient age was cited in six cases, and patient choice was cited in four cases. Follow-up (median, 34 months) did not show that disease-free or overall survival differences were related to age or to treatment (standard versus nonstandard).
Conclusions: These data demonstrate age-related variations in breast cancer treatment in a multidisciplinary breast care unit. Lower complication rates and equivalent short-term outcomes in women who received nonstandard therapy suggest good clinical judgment may have played a role in these differences. Although age-related patient preferences and comorbidity are relevant, the age-related attitudes of caregivers must also be taken into account to fully explain these variations.Presented at the 46th Annual Cancer Symposium of the Society of Surgical Oncology, Los Angeles, March 18–21, 1993. 相似文献
997.
Thomas GL 《Health facilities management》1994,7(6):56, 58, 60-56, 58, 61
998.
Information from a study group of doctors training or recentlytrained in occupational medicine was gathered using a self-administeredquestionnaire mailed to each subject's registered address. Ofthe 224 individuals identified from scrutiny of records heldby the Faculty of Occupational Medicine, replies were receivedfrom 181 (81 per cent). Recruitment occurs in broadly equalproportions from general practice, general practice trainees,the hospital sector and the forces, with a wide diversity ofexperience among trainees. On average, trainees experience atleast two industrial sectors during their training. There weredisappointingly small numbers in part-time training. 相似文献
999.
1000.
The Influence of Obesity on the Self-Reported Health Status of Chamorros and other Residents of Guam
Pinhey TK Heathcote GM Rarick J 《Asian American and Pacific Islander journal of health》1994,2(3):195-211
PURPOSE OF THE PAPER. We report on an analysis of the relationship of obesity to self-assessments of physical health for a probability sample of Guam's indigenous (Chamorro) and resident populations. Further, we examine whether Guam's populations fit a Western model, in terms of viewing obesity as an unhealthy condition. As background for our analysis, we review the literature on (1) the relationship between obesity and chronic noninfectious diseases; (2) social and behavioral associations of obesity; and (3) the reliability of self-assessed physical health and measures of obesity. METHODS. The data analyzed were taken from a Behavioral Risk Factor Survery (BRFS) conducted on Guam in 1991. We employed various standard univariate (chi-square analysis, ANOVA) and multivariate (OLS regression and logisitic regression analusis) statistical procedures in exploring our data and testing hypotheses on the correlates and associations of self-reported health and obesity. PRINCIPAL FINDINGS. Controlling for ethnicity, age, gender, marital and socioeconomic status, we found that obesity and being Chamorro was associated significantly with low assessments of physical health and that income was a signifcant predictor of higher self-assessments. A small sample of Micronesians, with a slightly greater level of obesity than the Chamorros, did not show the same tendency towards lower self-evaluation of their health. This probably reflects their lesser degree of internalizaition of Western ideas about obesity, appearance and health. When controlling for self-assessments of physical health, obesity was also shown to be related significantly with dieting by Chamorro women but was not a significant predictor of their increased participation in physical exercise. Young males were significantly more likely to report participation in physical exercise regardless of their weight or ethnicity. CONCLUSIONS. We hypothesize that historical (acculturative) changes to the diet and life ways of Chamorros, together with a likely genetic predisposition to store fat, has led to the relatively high levels of obesity seen on Guam today. Because of internalization of Western ideals about obesity and appearance, and increased community awareness of the health perils of obesity, Chamorros are at a public health crossroads. Effective health interventions must reckon with powerful genetic and cultural cross-currents. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS. Colleagues are encouraged to examine the effects of ethnicity and acculturation on the health attitudes, behaviors, and status of other Pacific Islander and Asian populations. The creation of such a comparative data base will service APIA health interventions. KEY WORDS. Guam, Chamorros, Asian Pacific Islander Americans, survey, obesity, self-evaluated health status, socioeconomic status, cross-cultural comparisons. 相似文献