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41.
Data are presented from sample surveys conducted in 1974 (N = 3,119) and 1975 (N = 657) in Alameda County, California, comparing discretionary health practices of Mexican Americans, Blacks, and Anglos. Practices include hours of sleep, regularity of meals, physical activity, obesity, smoking and drinking. Analyses reported focus on a summary measure of health practices and measures of smoking and exercise. Comparisons of crude percentages indicate that while there are differences among the groups, they are not dramatic. In general, Mexican Americans report fewer overall health practices, less exercise, and less smoking than Anglos. Controlling for the effects of age, sex, income, education, perceived health, health status, and use of health examinations reduces differences in overall health practices by decreasing Anglo rates and increasing rates for Chicanos and Blacks. However, even after adjustment for demographic and socioeconomic differences, rates remain lower for the two minority groups. Controlling for the effects of the eight covariates also reduces ethnic differences in exercise, but Chicanos still rank the lowest in terms of reported physical activity. By contrast, adjustment for demographic and socioeconomic differences does not reduce ethnic differentials in smoking behavior. Before and after adjustment Chicanos smoke least and Blacks smoke most. In general, controlling for socioeconomic status and health has the most effect, while some additional explanation is provided by age and sex. Overall, however, ethnicity and the covariates account for less than 10% of the variance in smoking and overall health practices, and less than 20% of the variance in exercise.  相似文献   
42.
Lee E  Im H  Oh E  Jung WW  Kang HS  Sul D 《Inhalation toxicology》2005,17(7-8):401-408
Single-cell gel electrophoresis assays were performed in order to evaluate DNA damage occurring in the T and B lymphocytes, spleens, bone marrow, and livers of rats exposed to benzene at a concentration of 100, 200, or 400 ppm for 2 or 4 wk. The level of t,t-muconic acid (t,t-MA), which is a urinary benzene metabolite, was determined. In the control rats, mean Olive tail moments in the T and B lymphocytes were 1.507 +/- 0.398 and 1.579 +/- 0.206, respectively. DNA damage in the T and B lymphocytes exposed to 400 ppm benzene for 4 wk caused those rats to exhibit the highest Olive tail moments, with their values measured as 4.351 +/- 0.510 and 3.140 +/- 0.631, respectively. Also, the t,t-MA levels increased directly with increasing benzene exposure time and dose during the 4 wk. After 4 wk, the levels of t,t-MA in urine from rats exposed to 100, 200, and 400 ppm were 19.30 +/- 5.62, 30.36 +/- 4.46, and 46.93 +/- 9.10 mg/g creatinine. In conclusion, the present study demonstrates that benzene exposure results in significant DNA damage in the T and B lymphocytes, bone marrow, spleens, and livers of rats. DNA damage in the blood cells and organs was also discovered to vary directly with benzene exposure, in both a dose-dependent and time-dependent manner. In addition, a similar trend regarding DNA damage was found in the blood cells and organs, and evidenced a good association with the level of t,t-MA in the urine.  相似文献   
43.

Objective

In the field of spinal surgery, a few laboratory results or clinical cases about robotic spinal surgery have been reported. In vivo trials and development of related surgical instruments for spinal surgery are required before its clinical application. We investigated the use of the da Vinci® Surgical System in spinal surgery at the craniovertebral junction in a human cadaver to demonstrate the efficacy and pitfalls of robotic surgery.

Methods

Dissection of pharyngeal wall to the exposure of C1 and odontoid process was performed with full robotic procedure. Although assistance of another surgeon was necessary for drilling and removal of odontoid process due to the lack of appropriate end-effectors, successful robotic procedures for dural sutures and exposing spinal cord proved its safety and dexterity.

Results

Robot-assisted odontoidectomy was successfully performed in a human cadaver using the da Vinci® Surgical System with few robotic arm collisions and minimal soft tissue damages. Da Vinci® Surgical System manifested more dexterous movement than human hands in the deep and narrow oral cavity. Furthermore, sutures with robotic procedure in the oral cavity demonstrated the advantage over conventional procedure.

Conclusion

Presenting cadaveric study proved the probability of robot-assisted transoral approach. However, the development of robotic instruments specific to spinal surgery must first precede its clinical application.  相似文献   
44.
45.
Background: The current hard tissue implants research aims to accelerate bone healing by designing surfaces that are bioactive. However, the role of the inflammatory response to these surfaces is so far incompletely described. Purpose: The aim of the study was to evaluate early inflammatory response in vitro to a potentially bioactive surface—an anodized surface with Mg ions incorporated (anodized/Mg)—and to compare it to a turned, a blasted, and an anodized surface. Materials and Methods: An interferometer was used for topographical characterizations. The disks were incubated with human mononuclear cells. Adherent cells were investigated with respect to number of cells, viability, differentiation, and cytokine production with and without lipopolysaccharide stimulation after 24 and 72 hours. Results: The number of adhered mononuclear cells differed significantly between the different modified surfaces, with the highest number on the anodized surface. However, there were no significant differences in cytokine production and differentiation between the different modified surfaces. The amount of anti‐inflammatory mediator interleukin‐10 remained over time, while the number of cells and pro‐inflammatory cytokine tumor necrosis factor‐α decreased. The cells were viable on all surfaces, respectively. Conclusion: The anodized surfaces with and without Mg ions showed an increased cell adherence, however, otherwise an inflammatory response similar to the turned and blasted surfaces. Furthermore, the potentially bioactive anodized/Mg surface showed a similar response to the TiUnite‐like anodized surface despite the former having a surface roughness of a smoother character.  相似文献   
46.
Capsule endoscopy (CE) requires placement of an eight-lead sensor array over the abdomen that receives image and localization data transmitted from the capsule. The current process of applying this array to the skin has several disadvantages: firstly, it is time-consuming; secondly, it can be cumbersome for the patient; and thirdly, it is often difficult to place the leads consistently. A new external sensor array system designed to improve this process was tested. It was hypothesized that the new method would be able to receive the transmitted data adequately during CE. The new method and device were tested on an in-patient who had two sets of sensor arrays, batteries, and data recorders placed on her simultaneously. One set was placed in the standard fashion, which served as the control, while the other set was placed using the novel external method. The data provided by the two recorders were compared and the patient's preferences were noted. The quality of the CE images provided by the two methods was identical, but the CE localization tracings were different, presumably due to movement of the gown and leads during the recording period. No signal interference was noted. The patient preferred the external device. A prepositioned external sensor array is capable of transmitting CE data without any loss in image quality, but the localization tracing differs due to movement of the external array. This new method will require testing with a larger sample size in an outpatient setting to allow full assessment of the clinical value of the new approach.  相似文献   
47.
PURPOSE: This study compared the speed and strength of osseointegration and osteoconductivity between an oxidized experimental magnesium (Mg) implant, an oxidized commercially available TiUnite implant, and a dual acid-etched surface Osseotite implant. The aim was to investigate which surface properties enhance bone response to implants, and thereby to test a biochemical bonding theory. MATERIALS AND METHODS: A total of 60 screw implants (20 of each design) were inserted through 1 cortex into the tibiae of 10 rabbits. Surface chemistry, oxide thickness, morphology, crystal structure, and surface roughness were evaluated. After healing times of 3 and 6 weeks, all bone implants were unscrewed with removal torque (RTQ) devices, and the bone specimens were subjected to histomorphometry. RESULTS: RTQ values for Mg, TiUnite, and Osseotite implants were 27.1, 21.3, and 15.4 Ncm, with new bone formation values of 29%, 18%, and 15%, respectively, at 3 weeks. At 6 weeks the RTQ values were 37.5, 36.4, and 21.5 Ncm, with new bone formation values of 39%, 31%, and 26%, respectively. Discussion: Mg implants demonstrated significantly greater RTQ values (P = .008 and P = .0001) and more new bone formation (P = .031 and P = .030) than Osseotite at 3 and 6 weeks, respectively. Mg implants also showed higher RTQ values at 3 weeks and new bone formation at 6 weeks than TiUnite, but neither were significant (P > .05). TiUnite showed significantly higher RTQ values than Osseotite at 6 weeks (P = .001), but was not significant at 3 weeks (P > .05). Osseointegration rate (deltaRTQ/deltaweeks) was significantly faster for Mg (P = .011) and TiUnite (P = .001) implants between 3 and 6 weeks of healing time, but was not significant for Osseotite. CONCLUSIONS: The results indicate that surface chemistry facilitated more rapid and stronger osseointegration of the Mg implants despite their minimal roughness compared to the moderately roughened TiUnite. This suggests potential advantages of Mg implants for reducing high implant failure rates in the early postimplantation stage and in compromised bone, making it possible to shorten bone healing time from surgery to functional loading, and enhancing the possibility of immediate/early loading.  相似文献   
48.
FK506 (tacrolimus) has been shown to be a safe and effective immunosuppressant for the prevention of organ rejection after liver and kidney transplantation. Like cyclosporine,

the use of FK506 has been associated with some adverse effects such as toxicity and organ rejection. Therapeutic monitoring of the whole-blood FK506 drug concentrations has been used in an effort to determine how the concentration of FK506 in the blood is related to the development of toxicity or the risk for organ rejection. Cox regression analysis of two recent clinical trials of FK506 in patients receiving kidney and liver transplants shows a significant correlation between the whole-blood FK506 concentrations and the incidence of both toxicity and organ rejection. Because of these relationships and the pharmacokinetics of FK506, therapeutic monitoring of the whole-blood FK506 levels is expected to be helpful for minimizing the risks of both toxicity and rejection in liver and kidney transplants.  相似文献   
49.
We developed nomograms to predict disease recurrence in patients with Ta, T1 transitional cell carcinoma of the bladder. Thirty-eight training hospitals participated in this retrospective multicenter study. Between 1998 and 2002, a total of 1,587 patients with newly diagnosed non-muscle invasive bladder cancer were enrolled in this study. Patients with prior histories of bladder cancer, non-transitional cell carcinoma, or a follow-up duration of less than 12 months were excluded. With univariate and multivariate logistic regression analyses, we constructed nomograms to predict disease recurrence, and internal validation was performed using statistical techniques. Three-year and five-year recurrence-free rates were 64.3% and 55.3%, respectively. Multivariate analysis revealed that age (hazard ratio [HR]=1.437, p<0.001), tumor size (HR=1.328, p=0.001), multiplicity (HR=1.505, p<0.001), tumor grade (HR=1.347, p=0.007), concomitant carcinoma in situ (HR=1.611, p=0.007), and intravesical therapy (HR=0.681, p<0.001) were independent predictors for disease recurrence. Based on these prognostic factors, nomograms for the prediction of disease recurrence were developed. These nomograms can be used to predict the probability of disease recurrence in patients with newly diagnosed Ta, T1 transitional cell carcinoma of the bladder. They may be useful for patient counseling, clinical trial design, and patient follow-up planning.  相似文献   
50.
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