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51.
Campylobacteriosis is a disease of worldwide importance, but aspects of its transmission dynamics, particularly risk factors, are still poorly understood. We used data from a matched case-control study of 4,269 men who have sex with men (MSM) and 26,215 controls, combined with national surveillance data on Campylobacter spp., Salmonella spp., and Shigella spp., to calculate matched odds ratios (mORs) for infection among MSM and controls. MSM had higher odds of Campylobacter (mOR 14, 95% CI 10–21) and Shigella (mOR 74, 95% CI 27–203) infections, but not Salmonella (mOR 0.2, 95% CI 0–13), and were less likely than controls to have acquired Campylobacter infection abroad (χ2 = 21; p<0.001). Our results confirm that sexual contact is a risk factor for campylobacteriosis and also suggest explanations for unique features of Campylobacter epidemiology. These findings provide a baseline for updating infection risk guidelines to the general population.  相似文献   
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Two middle age sisters had most manifestations of the SC phocomelia syndrome including postnatal growth retardation, symmetric limb deficiencies with radial aplasia and absent thumbs, facial anomalies with microcephaly, microphthalmia, hypoplastic nasal alae, and borderline to mild mental retardation. Unusual findings included congenital paralysis of some cranial nerves in both patients and malignant melanoma in the proposita. Cultured lymphocytes from both patients, and skin fibroblasts, Epstein Barr virus-transformed lymphocytes, and tumor cells from the proposita demonstrated premature separation of centromeric heterochromatin (PCS) of many chromosomes, a finding noted previously in the SC phocomelia syndrome and the similar but more severe Roberts syndrome. Extensive overlap of the phenotypes of the sisters and 15 other patients with either syndrome and PCS confirms that these are either allelic conditions or the same disease--designated Roberts-SC phocomelia syndrome. The role of PCS in the syndrome(s) remains uncertain since some patients with the characteristic clinical phenotypes are reported to lack it.  相似文献   
54.
High expectations may contribute to stress in the patient and dentist during dental treatment. Esthetic and restorative results can be predicted for laminate veneers by using a powder blower and a liquid dispenser preoperatively to form self-cured resin veneers. Trial veneers are formed in a precision "salt and pepper" technique that conserves materials and time. The trial veneers are placed, without tooth preparation, on the treatment site so that the patient can preview the planned treatment and so that the dentist can explain proposed treatment in a reversible procedure. This may circumvent misunderstandings between dentist and patient and allow the consideration of alternate treatment plans.  相似文献   
55.
Every year, analysts in the Health Care Financing Administration present figures on what our Nation spends for health. As the result of a comprehensive re-examination of the definitions, concepts, methods, and data sources used to prepare those figures, this year's report contains new estimates of national health expenditures for calendar years 1960 through 1988. Significant changes have been made to estimates of spending for professional services and to estimates of what consumers pay out of pocket for health care. In the first article, trends in use of and expenditure for various types of goods and services are discussed, as well as trends in the sources of funds used to finance health care. In a companion article, the benchmark process is described in more detail, as are the data sources and methods used to prepare annual estimates of health expenditures.  相似文献   
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重度肥胖患者胃肠分流术后低氧血症机制的分析   总被引:2,自引:0,他引:2  
目的 研究重度肥胖对胃肠分流术后动脉血氧分压的影响。方法 对 6 1例进行胃肠分流术的重度肥胖患者及 5 5例择期腹部手术的正常体重患者进行术前肺功能、术前及术后 1~ 5d的血气分析检测。结果 肥胖组术后1~ 5d、对照组术后 1~ 2d的动脉血氧分压较术前显著下降 (P <0 .0 5 ) ;肥胖组术后 1~ 2d动脉血氧分压与其最大分钟通气量及腰臀比显著相关 (P <0 .0 0 0 1)。结论 重度肥胖者较正常体重患者在腹部手术后发生低氧血症的程度较严重且持续时间长。  相似文献   
57.
Background: upper body, or abdominal, distribution of body fat is associated with a number of metabolic and hormonal aberrations that could influence resting energy expenditure REE. The purpose of our study was to examine the effects of fat distribution on REE of 96 morbidly obese premenopausal females. Methods: the study population consisted of three groups of study subjects, 32 with lower body fat distribution (LBD) and waist-to-hip circumference ratios WHR < 0.80, 20 with intermediate (INT) fat distribution and WHR between 0.80 and 0.85 and 34 females with upper body distribution of fat (UBD) and WHR > 0.85. Indices measured included: (1) REE; (2) maximal oxygen consumption during an exercise tolerance test (VO2max); (3) basal respiratory quotient (RQ); (4) fasting blood glucose; and (5) serum cholesterol and triglycerides. Results: we found that morbidly obese women who store fat abdominally (WHR > 0.80) have significantly (p < 0.01) higher REE (kcal per h per BSA) than those with lower body obesity. Levels of triglyceride and glucose of the UBD group were also higher than those of the LBD subjects, i.e. 35% and 23%, respectively. VO2max and RQ were similar between the study groups, suggesting that the elevated REE of the patients with abdominal adiposity were likely not the result of their greater muscle mass or differences in substrate utilization. Conclusion: fat distribution affects REE in morbidly obese premenopausal females, and further research is needed to identify the various entities regulating REE in the morbidly obese.  相似文献   
58.
This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine.  相似文献   
59.
We conducted a double-blinded, randomized, cross-over, prospective trial to evaluate the pain relief effect of millimeter waves (MW) under experimental conditions. The cold pressor test was used as a model of tonic aching pain. Twelve healthy male volunteers were exposed to an active medical MW generator and to a disabled sham generator with at least 24 h between exposures. Characteristics of continuous-wave electromagnetic output from the active generator were: wavelength 7.1 mm, incident power density 25 +/- 5 mW/cm2, and duration of exposure 30 min. MW produced a significant (P < 0.05) suppression of pain sensation, with an average 37.7% gain in pain tolerance and a 49.3% increase in pain sensitivity range (the latter being the difference between pain tolerance and pain threshold values). Of the 12 volunteers, 7 (58.3%) reacted to the active MW generator with an increased pain tolerance, and the individual reactions varied from 120% to 315% comparison with their own preexposure levels. MW therapy can potentially be used as a supplementary or alternative treatment for pain relief. Implications: Pain management is still a significant medical problem. In a double-blinded, experimental setting, we confirmed that low-intensity millimeter wave therapy can reduce pain sensitivity in healthy human volunteers and can potentially be used as a supplementary or alternative treatment for pain relief.  相似文献   
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