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71.
72.
以不同电性的基团取代顺-3-甲基芬太尼中4-N-丙酰基上的乙基,合成某些顺-3-甲基芬太尼的结构类似物。药理试验结果表明,所合成的化合物均有典型的吗啡样作用。化合物3的镇痛活性略强于顺-3-甲基芬太尼。应用半经验的INDO方法对4个代表化合物进行了量子化学计算,讨论了电子结构与镇痛活性间的关系,化合物3由于氯乙烯基的引入具有与顺-3-甲基芬太尼不同的电子结构特征,氯乙烯基可能作为电子接受体参与了与受体的作用。  相似文献   
73.
The purpose of this study was to determine the occlusal status in young Asian male adults of three ethnic groups. Study models of a sample of male army recruits (N = 339, age 17-22 years) with no history of orthodontic treatment were assessed. The ethnic proportions of the sample were Chinese 76.1% (n = 258), Malay 17.7% (n = 60), and Indian 6.2% (n = 21). British Standard Institute (BSI) and Angle's classification were used to determine incisor and molar relationships, respectively. Chi-square test or Fisher's Exact test was performed to compare the occlusal traits between ethnic groups. The distribution of incisor relationships of the total sample consisted of Class I = 48.1%, Class II/1 = 26.3%, Class II/2 = 3.2%, and Class III = 22.4%. Right Angle's molar relationships were 49.9%, 24.5%, and 24.2% whereas left Angle's molar relationships were 53.1%, 25.1%, and 21.2% for Class I, II, and III, respectively. Comparison between ethnic groups found that Indian subjects were more likely to have Class II/1 malocclusions and clinically missing permanent teeth (P < .05). The study found that the overall prevalence of malocclusion (BSI) was Class I, Class II/1, Class III, and Class II/2 in descending order of proportions. Angle's Class I molar was most prevalent followed by Class II and Class III relations. A significant difference in occlusal status between the ethnic groups was found regarding incisor relationship and missing permanent teeth (P < .05).  相似文献   
74.

Background

The natural resistance-associated macrophage protein 1 (NRAMP1) gene is associated with susceptibility to Mycobacterium tuberculosis in humans and to bacillus Calmette-Guérin (BCG) in mice. The detoxification enzyme, human glutathione peroxidase 1 (hGPX1), is associated with recurrence of bladder cancer (BCa).

Objective

To determine whether NRAMP1 and hGPX1 gene polymorphisms correlate with response to BCG immunotherapy for non–muscle-invasive BCa (NMIBC).

Design, setting, and participants

DNA was obtained from the peripheral blood of 99 NMIBC patients who were prospectively randomized to receive postresection intravesical BCG (81 mg [n = 50] or 27 mg [n = 19]) or BCG (27 mg) with interferon alpha (IFN-α; n = 30). The median follow-up time was 60 mo.

Intervention

Intravesical BCG or BCG–IFN-α.

Measurements

Restriction fragment length polymorphism (RFLP) analysis was performed to identify polymorphisms in the NRAMP1 promoter region (GT repeat number) and at position 543 (aspartate [D] and/or asparagine [N] expression) within the NRAMP1 protein (D543N) and position 198 (proline and/or leucine expression) within the hGPX1 protein (Pro198Leu). Data were analyzed using χ2 analysis, multivariate analysis, and Kaplan-Meier curves.

Results and limitations

On univariate analysis, the NRAMP1 D543N G:G genotype had decreased cancer-specific survival (CSS; p = 0.036). The hGPX1 CT genotype (Pro-Leu) had decreased recurrence time (p = 0.03) after BCG therapy. On multivariate analysis, patients with the NRAMP1 D543N G:G genotype and allele 3 (GT)n polymorphism had decreased recurrence time (p = 0.014 and p = 0.03) after BCG therapy. The limitation of this study was its small sample size.

Conclusions

Polymorphisms of the NRAMP1 and hGPX1 genes may be associated with recurrence of BCa after BCG immunotherapy.  相似文献   
75.
OBJECTIVE: To establish if there are ethnic differences in the various metabolic disturbances that are common with clozapine treatment. METHOD: Forty subjects (20 Asians and 20 Caucasians) with a diagnosis of schizophrenia were recruited for the study. Clozapine blood levels as well as fasting blood glucose, lipid levels, and liver function tests were established. Other clinical parameters such as blood pressure and Body Mass Index (BMI) were recorded for each patient. RESULTS: The mean clozapine dose was significantly higher in the Caucasian subjects (432.5+/-194.7 mg) as compared to the Asian subjects (175.6+/-106.9 mg) (p<0.001) while the mean weight-corrected dose for Asian patients was lower (3.0+/-1.9 and 5.0+/-2.1 mg/kg, respectively, p=0.005). There were, however, no ethnic differences in the mean plasma clozapine concentration (415.3+/-185.8 ng/ml in Caucasians and 417.1+/-290.8 ng/ml in Asians). BMI were significantly higher in Caucasians, as were the number of subjects with hypertension; levels of hepatic enzymes were higher in the Asian group. CONCLUSIONS: Not only are there pharmacokinetic differences between Asian and Caucasian patients receiving clozapine, but there may also be differential emergence of certain metabolic abnormalities like hypertension and weight gain in these two ethnic groups. However, the effects of life style including diet and exercise cannot be excluded.  相似文献   
76.
Umapathi T  Tan WL  Tan NC  Chan YH 《Muscle & nerve》2006,33(6):742-746
We studied the relationship between epidermal innervation and age, gender, height, and weight. Intraepidermal nerve fiber density (IENFD) of skin biopsies obtained from the proximal thigh and ankle of 84 normal individuals was quantified. A linear regression model was performed using IENFD at the thigh, IENFD at the ankle, and the thigh IENFD/ankle IENFD ratio, with age, gender, and height-weight interaction as predictors. An independent, negative correlation was found between age and IENFD at the ankle. No correlation was found between age and IENFD at the thigh. With increasing age the thigh IENFD/ankle IENFD ratio, a measure of the length-dependent distal-to-proximal gradient of epidermal nerve density, increased significantly. Gender, height, and body weight did not independently influence IENFD at either site. In normal individuals, distal epidermal innervation decreases in a length-dependent manner with advancing age. This must be considered when interpreting IENFD in disease states.  相似文献   
77.
The study, conducted in 2003–2005, was aimed at investigating the pattern of benzodiazepine (BZD) use and the attitudes and perceptions of doctors' prescribing practices by a hundred BZD-dependent patients in Singapore. Data on patients' demographic characteristics, psychiatric profiles, patterns of BZD use, and perceptions about doctors' prescribing practices were collected. A benzodiazepine dependence self-report questionnaire (Bendep-SRQ) was also administered. The mean age of the study participants was 39.4 years (SD = 9.7); 88% were Chinese, 58% were males, 46% were married, 48% had received secondary school education, and 48% were unemployed. BZD abuse in Singapore is contributed to by both doctor-shopping behavior and doctors' prescribing practices. Doctors need training on the assessment and management of BZD dependence. The study's limitations were noted. This project was supported by an institutional block grant received from the National Medical Research Council, Singapore.  相似文献   
78.
柏亚玲  娄皓  马春燕  董燕 《医学争鸣》2005,26(21):2005-2005
1 临床资料 2000-12/2005-01进行人工耳蜗植入手术的深度双耳感音神经性耳聋患者62(男37,女25)例,年龄1.2~21.0岁;语前聋60例,语后聋2例;先天性27例(其中用药17例,患腮腺炎2 例,原因不明25例),术前常规行颞骨薄层CT,部分患者行MRI扫描;术中面神经监测,所有患者经听力学评估均行右侧人工耳蜗植入.  相似文献   
79.
INTRODUCTIONTwo strategies are available for prevention of early-onset group B streptococcal (GBS) sepsis – clinical risk factor-based screening and routine culture-based screening of pregnant women for GBS colonisation. In our hospital, we switched from the former to the latter approach in 2014.METHODSWe compared the incidence of early-onset GBS sepsis during 2001–2015 between infants born to pregnant women who were screened for GBS colonisation and those born to women who were not screened.RESULTSAmong 41,143 live births, there were nine cases of early-onset GBS sepsis. All infants with GBS sepsis were born to pregnant women who were not screened for GBS colonisation. The incidence of early-onset GBS sepsis among infants of women who were not screened was 0.41 per 1,000 live births (95% confidence interval [CI] 0.19–0.77) when compared to infants of women who were screened, for whom the sepsis incidence was zero per 1,000 live births (95% CI 0–0.19; p = 0.005).CONCLUSIONOur data suggests that routine culture-based screening of pregnant women for GBS colonisation is a better preventive strategy for early-onset GBS sepsis in neonates when compared to clinical risk factor-based screening.  相似文献   
80.
OBJECTIVE The aim of this study was to provide a comprehensive benchmark of 30-day ventriculoperitoneal(VP)shunt failure rates for a single institution over a 5-year study period for both adult and pediatric patients,to compare this with the results in previously published literature,and to establish factors associated with shunt failure.METHODS A retrospective database search was undertaken to identify all VP shunt operations performed in a single,regional neurosurgical unit during a 5-year period.Data were collected regarding patient age,sex,origin of hydrocephalus,and whether the shunt was a primary or secondary shunt.Operative notes were used to ascertain the type of valve inserted,which components of the shunt were adjusted/replaced(in revision cases),level of seniority of the most senior surgeon who participated in the operation,and number of surgeons involved in the operation.Where appropriate and where available,postoperative imaging was assessed for grade of shunt placement,using a recognized grading system.Univariate and multivariate models were used to establish factors associated with early(30-day)shunt failure.RESULTS Six hundred eighty-three VP shunt operations were performed,of which 321 were pediatric and 362 were adult.The median duration of postoperative follow-up for nonfailed shunts(excluding deaths)was 1263 days(range 525-2226 days).The pediatric 30-day shunt failure rates in the authors'institution were 8.8%for primary shunts and 23.4%for revisions.In adults,the 30-day shunt failure rates are 17.7%for primary shunts and 25.6%for revisions.In pediatric procedures,the number of surgeons involved in the operating theater was significantly associated with shunt failure rate.In adults,the origin of hydrocephalus was a statistically significant variable.Primary shunts lasted longer than revision shunts,irrespective of patient age.CONCLUSIONS A benchmark of 30-day failures is presented and is consistent with current national databases and previously published data by other groups.The number of surgeons involved in shunt operations and the origin of the patient's hydrocephalus should be described in future studies and should be controlled for in any prospective work.The choice of shunt valve was not a significant predictor of shunt failure.Most previous studies on shunts have concentrated on primary shunts,but the high rate of early shunt failure in revision cases(in both adults and children)is perhaps where future research efforts should be concentrated.  相似文献   
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