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41.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.  相似文献   
42.
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.  相似文献   
43.
The study objective was to determine the effectiveness of a phenotypic chemoresponse assay in predicting response to chemotherapy measured by progression-free interval (PFI) in a retrospective series of ovarian cancer patients whose tumor specimens had been tested with the ChemoFx assay. A statistically significant correlation between assay prediction of response and PFI was observed in 256 cases with an exact or partial match between drug(s) assayed and received. In 135 cases with an exact match, the hazard ratio for progression of the resistant group was 2.9 (confidence interval [CI]: 1.4-6.3; P < 0.01) compared to the sensitive group and 1.7 (CI: 1.2-2.5) for the intermediate compared to the sensitive group. The median PFI for patients treated with drugs assayed as resistant was 9 months, 14 months for those with drugs assayed as intermediately sensitive, and PFI had not been achieved for those with drugs assayed as sensitive. These data indicate that the ChemoFx assay is predictive of PFI in ovarian cancer. As the majority of ovarian cancers display different degrees of response to different chemotherapy agents ex vivo, the incorporation of assay information into treatment selection has the potential to improve clinical outcomes in ovarian cancer patients.  相似文献   
44.
OBJECTIVE: To describe the dieting histories of bariatric surgery candidates. RESEARCH METHODS AND PROCEDURES: One hundred seventy-seven individuals with extreme obesity who sought bariatric surgery completed the Weight and Lifestyle Inventory, a self-report instrument that assesses several variables, including weight and dieting history. Patients' dieting histories were further explored with an aided recall during a preoperative behavioral/psychological evaluation performed by a mental health professional. RESULTS: Participants who completed the Weight and Lifestyle Inventory reported an average of 4.7 +/- 2.9 successful dieting attempts, defined as those that resulted in a loss of 10 lbs (4.5 kg) or more. These individuals reported a mean total lifetime weight loss of 61.1 +/- 41.3 kg. Despite these efforts, their weight increased from 89.4 +/- 27.4 kg at the time of their first diet (age 21.2 +/- 10.1 years) to 144.5 +/- 30.8 kg at the time they underwent their behavioral/psychological evaluation (age 43.0 +/- 11.0 years). Results of the aided recall revealed that participants had made numerous other efforts to lose weight that were unsuccessful. Self-directed diets and commercial programs were used more frequently. DISCUSSION: Individuals who sought bariatric surgery reported an extensive history of dieting, beginning in adolescence, that was not successful in halting progressive weight gain. Thus, the recommendation often made by insurance companies that patients delay surgery to attempt more conservative treatment options may be unwarranted, particularly in the presence of significant obesity-related comorbidities. Weight loss histories should be routinely examined during a behavioral evaluation to determine whether additional attempts at non-surgical weight loss are advisable. Future studies also are needed to explore the potential relationship between dieting history and postoperative outcome.  相似文献   
45.
PURPOSE: Evaluate the effectiveness of body mass index (BMI) tables placed in exam rooms as an intervention to encourage providers to calculate and record BMI scores in patients' medical records. DESIGN: In a prospective cohort design, medical record data for 276 adult patients at a federally funded community health center in New England were examined from August 2000 to August 2002 following the intervention. METHODS: Prominent, multicolored, laminated BMI tables were posted in the exam rooms of one of the study site's three primary health care teams. Medical record data collected included documentation of BMI calculation in medical records, documentation of an obesity diagnosis, and inclusion of heights and current weights. Frequency distributions were calculated; chi-square tests were used to identify associations. FINDINGS: In contrast to the comparison teams, patients on the intervention team were more likely to have BMI recorded in the medical record. A statistically significant increase in the diagnosis of obesity was observed throughout the health center after the intervention. CONCLUSIONS: Posting BMI tables in exam rooms contributed to increased BMI documentation in patients' medical records.  相似文献   
46.
The impact of obesity on female reproductive function   总被引:1,自引:0,他引:1  
Obesity may be described as the new worldwide epidemic, and its serious impact on morbidity and mortality are well known. As more and more women become obese, the reproductive problems associated with obesity present an ever-growing challenge to physicians involved in their fertility care. The spectrum of reproductive problems associated with obesity encompasses a wide range of disorders including infertility problems, miscarriage and pregnancy complications. In this review, we aim to discuss the impact of obesity on the various aspects of female reproductive function with focus on the clinical aspects of fertility problems in obese women. We finally comment on the available therapeutic options available to this group of women.  相似文献   
47.
Theoretical and simulation evidence is presented in support of the idea that the optimal manner of determining blood flow from MR perfusion studies is not necessarily obtained by setting experimental conditions to maximize either the arterial input or the measured tissue concentration level for a particular echo time (TE). The noise power in the contrast concentration curve is associated with its peak because of the nonlinear relationship between the contrast concentration and MR signal intensity curves. The optimum signal-to-noise ratio (SNR), SNR(C), for a particular contrast concentration curve can be obtained when the experimental concentration level and TE are adjusted to produce an MR intensity curve whose signal loss is 63% of the precontrast MR signal intensity. It is demonstrated that the stability of the singular valued decomposition (SVD) deconvolution approach to determine blood flow parameters is increased when the tissue curve maximum signal loss is in the range of 40-80%. The accuracy and stability of the SVD-determined blood flow parameters are affected by deviations from these optimum conditions in a manner that depends on the mean transit time (MTT) associated with the residue function. It is recommended that the experimental TE value be set so that neither the tissue nor the arterial curves are placed a region of rapidly deteriorating SNR(C).  相似文献   
48.
研究补肾抗衰口服液对大鼠衰老模型免疫器官胸腺和脾脏的影响.结果显示,模型组大鼠胸腺和脾脏重量减轻,胸腺重/体重比值、脾重/体重比值减小,胸腺组织学观察,显示萎缩改变;药物组大鼠胸腺和脾脏重量、胸腺重/体重、脾重/体重比值接近正常对照组,胸腺组织学观察,未显示萎缩改变.本研究结果表明,补肾抗衰口服液能延缓胸腺和脾脏萎缩,保护机体的正常免疫功能,提示该药有抗衰老的作用.  相似文献   
49.
Background: The gastric bypass operation has evolved since 1966 when it was first introduced. The purpose of this study was to determine the present state of gastric bypass by consensus among the members of the American Society for Bariatric Surgery (ASBS). Method: A questionnaire was sent to all members of the ASBS. Forty-three percent responded reporting over 41,200 cases. Results: Results were analyzed by using χ2 tests with a null hypothesis. Surgeons agreed on several technical aspects, preferring a vertical to a horizontal stapleline; estimating, rather than measuring, the pouch volume at an average of 22 cc. Few surgeons divide the short gastric vessels, and only 25% of surgeons polled use a restrictive ring or band proximal to the gastroenterostomy. Most surgeons calibrate the gastroenterostomy, reporting a preferred average diameter of 12.3 cm. There was no consensus regarding forming the gastroenterostomy, 58% preferring hand-sewn and 42% stapled anastomoses. There was no consensus regarding dividing the gastric pouch from the bypassed stomach: Conclusion: The preferred gastric bypass is vertical, with the pouch estimated at 20-25 cc, and the gastroenterostomy calibrated at 12 mm diameter. The short gastric vessels need not be divided, and restrictive bands or rings are not preferred. This technique of gastric bypass should be used as the control procedure when modifications are tested in future trials. Randomized prospective studies are suggested to probe the benefits of division of the stomach pouch from the bypassed stomach.  相似文献   
50.
Obesity in youth and middle age and risk of colorectal cancer in men   总被引:5,自引:0,他引:5  
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services.  相似文献   
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