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81.
Zhang L  Cheung KJ  Lam WL  Cheng X  Poh C  Priddy R  Epstein J  Le ND  Rosin MP 《Cancer》2001,91(11):2148-2155
BACKGROUND: Two staging systems for oral leukoplakias have been proposed to better predict prognosis. Although one system includes site as an independent determinant, its use is controversial. METHODS: Recent studies have shown that loss of heterozygosity (LOH) in oral premalignancies is associated with risk of progression. The authors analyzed 127 oral dysplasias for LOH on 3 chromosome arms (3p, 9p, and 17p). The lesions included 71 from the floor of mouth, ventrolateral tongue, and soft palate complex (designated high risk [HR] sites) and 56 from the rest of the oral cavity (low risk [LR] sites). RESULTS: Dysplasias from HR sites contained significantly higher LOH frequencies than LR sites (percentage with any loss, P = 0.0004; percentage with multiple losses, P = 0.0001; percentage loss on each of the arms, P < 0.05). Loss on 3p and/or 9p, a pattern associated with a 24-fold increased risk of progression (Rosin MP, Cheng X, Poh C, Lam WL, Huang Y, Lovas J, et al. Use of allelic loss to predict malignant risk for low-grade oral epithelial dysplasia. Clin Cancer Res 2000;6:357-62) was more frequent among HR lesions (P = 0.0005). Loss of heterozygosity frequencies were elevated at HR sites among both genders and among smokers and nonsmokers. For different histologic groups, LOH frequencies were elevated for HR sites in mild dysplasias (P < 0.05) and moderate dysplasias (marginal significance, P = 0.06), but not in severe dysplasias/carcinoma in situ. CONCLUSIONS: Anatomic location of mild and moderate oral dysplasias in Western populations may be an important diagnostic indicator because lesions at HR sites have a greater tendency to include genetic alterations associated with elevated risk of progression.  相似文献   
82.
A limited number of access ports used in laparoscopic surgery may impair the ability of the surgeon to achieve adequate retraction and exposure, or to stabilize "moving targets" while operating on nonfixed organs. Solutions such as adding more ports or using a hand-assisted technique have the disadvantages of being more invasive, possibly creating a cumbersome situation of multiple instruments in a limited working space. We describe a useful technique for retraction and stabilization with the use of temporary sutures that pass through the abdominal wall. Although not new, this technique is not widely known or used, and laparoscopic surgeons may find it useful for a variety of applications. apd: 11 May 2001  相似文献   
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84.
Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.

Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants.  相似文献   
85.
Bacteremia during extracorporeal shock wave lithotripsy of renal calculi   总被引:2,自引:0,他引:2  
An increasing incidence of bacterial endocarditis has been observed since the beginning of the last decade. An explanation for this fact is the expansion of diagnostic and therapeutic procedures in diverse medical disciplines. In a clinical study performed on 49 consecutive patients undergoing extracorporeal shock wave lithotripsy a 14.3% rate of bacteremia was detected during treatment. The bacterial spectrum consisted of gram-positive cocci, gram-negative cocci, Bacteroides capillosus and Proteus mirabilis. In principle, these results do not call for an antibiotic prophylaxis. Nevertheless, according to the recommendations of the American Heart Association and the Deutsche Gesellschaft für Herz- und Kreislaufforschung, patients with a cardiac risk predisposing to bacterial endocarditis must receive perioperative antibiotic prophylaxis.  相似文献   
86.
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.  相似文献   
87.
88.
Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day.  相似文献   
89.
90.
Variations in the response of individuals to beta-carotene supplementation were studied by measuring the accumulation of beta-carotene in oral mucosa cells. Beta-carotene was administered orally to 178 individuals for 3 consecutive days, exfoliated oral mucosa cells were collected by brushing the entire oral mucosa on the 7th day following supplementation, and the beta-carotene content was measured by HPLC analysis of the pronase-treated cells. The rise in beta-carotene levels in the oral mucosa following supplementation varied considerably. Significant differences in mean beta-carotene levels in the oral mucosa were observed in 4 population groups. After supplementation, beta-carotene levels increased by factors of 10.3 (100 Mile House), 7.8 (Williams Lake), 6.9 (Lytton) and 3.4 (Vancouver), respectively. This difference in mean beta-carotene values is due to there being different proportions of weak and strong responders in the various population groups. Neither peak levels nor increases in beta-carotene levels were correlated with base-line concentrations of beta-carotene in the pre-supplementation samples. A second supplementation was given to 54 individuals several months after the initial supplementation. Of 17 weak responders in the first supplementation study, 10 (58.8%) individuals again showed only a small increase. A time-course study revealed that low responders showed no significant changes in beta-carotene levels over the 21 days following supplementation. Particular attention should be paid to weak responders when results of intervention trials using beta-carotene are interpreted.  相似文献   
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