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41.
During the Iran-Iraq war (1980-1988), sulfur mustard (as a chemical warfare agent) was launched on several occasions. Thirty-two victims with acute mustard poisoning were referred to our dermatology department, and are basis of this clinicopathologic study. Clinical and laboratory findings of these 32 adult patients exposed to mustard gas were determined. Skin biopsies were obtained from all of the patients and studied after staining of the specimens with routine and special stains. Clinically the most frequently involved areas were genitalia, face and axilla. The most common cutaneous findings were erosions, erythema and hyperpigmentation. The histopathologic changes of skin induced by mustard gas, included four distinct patterns: 1. Interface dermatitis, vacuolar type and lichenoid type; 2. Spongiotic dermatitis and bullous dermatitis (with or without acantholysis); 3. Pigmentary disorder pattern, increase of epidermal melanization. 4. Alteration of dermis/hypodermis, sclerodermoid pattern, vasculopathy and appendageal inflammatory response. Despite some specific characteristics related to sulfur mustard effect, these findings were compatible with histopathological changes of the chemical burns.  相似文献   
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OBJECTIVE: This study was designed to compare psychiatrists with other physicians on measures of academic performance before, during, and after medical school. METHOD: More than three decades of data for graduates of Jefferson Medical College (N=5,701) were analyzed. Those who pursued psychiatry were compared to physicians in seven other specialties on 18 performance measures. Analysis of covariance was used to control for gender effect. RESULTS: Compared to other physicians, psychiatrists scored higher on measures of verbal ability and general information before medical school and on evaluations of knowledge and skills in behavioral sciences during medical school, but they scored lower on United States Medical Licensing Examinations step 3. CONCLUSIONS: The results generally confirmed the authors' expectations about psychiatrists' academic performance. More attention should be paid to the general medical education of psychiatrists.  相似文献   
44.
BACKGROUND: Control of hyperlipidemia is vital in patients with cardiovascular disease (CVD). Omega-3 fatty acids (n-3FAs) have desirable effects on serum triglyceride (TG) levels, thrombosis, and arrhythmia, but lead to increases in serum low-density lipoprotein (LDL) and apo-B as well. OBJECTIVE: To determine and compare the effects of administration of n-3FAs, vitamin C (VitC) and n-3FAs + VitC on the serum levels of LDL, apoB, other serum lipids, and malondialdehyde (MDA). The present study was performed in Tehran University of Medical Sciences from 2000 to 2001. DESIGN: In a double-blind, placebo trial of parallel design, 68 hyperlipidemic patients [total cholesterol (TC) and TG greater than 200 mg/dL] were randomly assigned to receive daily 500 mg VitC, 1 g n-3FAs, 500 mg VitC + 1 g n-3FAs, or placebo (control) for 10 weeks. Fasting blood samples were collected at the beginning and at the end of the period. TG, TC, LDL-cholesterol-C (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) were measured enzymatically, VitC and MDA colorimetrically, and apo-B and apo-A-I immunoturbidometrically. The pattern of food consumption, socio-economic, and anthropometric indices were determined; there was no significant change in these indices during the study. RESULTS: There was a significant difference in the blood VitC level at the end of the study in comparison to the initial value in the VitC (p = 0.001) and VitC + n-3FAs (p = 0.027) groups. Similarly, the serum TG level at the end of study was significantly different from the initial value in the n-3FAs group (p = 0.002) and also from the final value in the control group (p = 0.013). In the VitC group, there was a significant decrease in TC (p = 0.004), apo-B (p = 0.005), and MDA (p = 0.015) at the end of study as compared to the respective initial values. There was also a significant increase in blood VitC compared to the control value (p = 0.018) and a significant decrease in MDA compared to the n-3FAs group (p = 0.034). At the end of study, in the n-3FAs group, there was a significant (p = 0.04) and a marginally significant decrease (p = 0.05), respectively, in TG/HDL and apo-B levels as compared to the initial values, and the TG/HDL ratio showed a significant decrease as compared to the control group (p = 0.047). CONCLUSION: Simultaneous administration of n-3FAs and VitC had no beneficial effects on the lipid profile of hyperlipidemic patients, but 1 g purified n-3FAs daily for 10 weeks is a beneficial supplement for decreasing TG without any increase in LDL-C, apo-B or MDA. Administration of 500 mg VitC for more than 10 weeks might decrease significantly TC and apo-B in hyperlipidemic patients.  相似文献   
45.
Despite the emphasis placed on physicians' lifelong learning, no psychometrically sound instrument has been developed to provide an operational measure of the concept and its components among physicians. The authors designed this study to develop a tool for measuring physician lifelong learning, to identify its underlying components and to assess its psychometric properties. A 37-item questionnaire was developed, based on a review of literature and the results of two pilot studies. Psychometric analyses of the responses of 160 physicians identified 19 items that were included in the Jefferson Scale of Physician Lifelong Learning. Factor analysis of the 19 items showed five meaningful factors that were consistent with the definition and major features of lifelong learning. They were 'need recognition', 'research endeavor', 'self-initiation', 'technical skills' and 'personal motivation'. The method of contrasted groups provided evidence in support of the validity of the five factors. The factors' reliability was assessed by coefficient alpha. It is concluded that lifelong learning is a multifaceted concept, and its operational measure is feasible for evaluating different educational programs and for studying group differences among physicians.  相似文献   
46.
BACKGROUND and objective: Propofol produces anaesthesia with rapid recovery but also causes pain or discomfort on injection. The effect of remifentanil in prevention of propofol-induced injection pain has been demonstrated in earlier studies. However, sufentanil, an opioid analgesic, has not been evaluated as an agent for managing pain on injection of propofol. In this study we aimed to compare the efficacy of remifentanil and sufentanil for the prevention of propofol-induced pain. METHODS: This double-blind, placebo-controlled clinical study was carried out from July 2006 to February 2007, and included patients who were candidates for elective surgery in a university hospital. From 92 American Society of Anesthesiologists (ASA) status I-II adult patients, 80 were randomly assigned to four groups of 20 each. Patients received 2 mL of sufentanil 0.01 mg, 2 mL of remifentanil 0.01 mg, 2 mL of remifentanil 0.02 mg, or 2 mL of saline 60 seconds prior to administration of 5 mL of propofol 1%. Patients were asked prior to losing consciousness whether they felt any pain due to propofol injection, and their pain scores were evaluated on the four-point scale of Ambesh et al. RESULTS: The incidence of pain was significantly lower in the remifentanil 0.02-mg group, remifentanil 0.01-mg group and sufentanil group compared with the saline group (40%, 70%, 75% and 100%, respectively, p < 0.05). Median pain intensity scores were significantly lower in the group receiving remifentanil 0.02 mg than in the sufentanil group (0 and 1 respectively, p < 0.05). The median intensity of propofol-induced pain was statistically similar between the groups receiving sufentanil or remifentanil 0.01 mg and the placebo group (1, 1 and 1, respectively, p > 0.05). CONCLUSION: Remifentanil 0.02 mg administered over 60 seconds before propofol administration is more effective than sufentanil 0.01 mg, remifentanil 0.01 mg or placebo administered 1 minute prior to propofol in reducing the incidence and intensity of injection pain.  相似文献   
47.
The role of white blood cell (WBC) count in pathogenesis of diabetes, cardiovascular disease, and obesity-related disorders has been reported earlier. Recent studies revealed that higher WBC contributes to atherosclerotic progression and impaired fasting glucose. However, it is unknown whether variations in WBC and haematologic profiles can occur in healthy obese individuals. The aim of this study is to further evaluate the influence of obesity on WBC count, inflammatory biomarkers, and metabolic risk factors in healthy women to establish a relationship among variables analyzed. The sample of the present study consisted of 84 healthy women with mean age of 35.56±6.83 years. They were categorized into two groups based on their body mass index (BMI): obese group with BMI >30 kg/m2 and non-obese group with BMI <30 kg/m2. We evaluated the relationship between WBC and platelet count (PLT) with serum interleukin 6 (IL-6), C-reactive protein (CRP), angiotensin Π (Ang Π), body fat percentage (BF %), waist-circumference (WC), and lipid profile. WBC, PLT, CRP, and IL-6 in obese subjects were significantly higher than in non-obese subjects (p< 0.05). The mean WBC count in obese subjects was 6.4±0.3 (×109/L) compared to 4.4±0.3 (×109/L) in non-obese subjects (p=0.035). WBC correlated with BF% (r=0.31, p=0.004), CRP (r=0.25, P=0.03), WC (r=0.22, p=0.04), angiotensin Π (r=0.24, p=0.03), triglyceride (r=0.24, p=0.03), and atherogenic index of plasma (AIP) levels (r=0.3, p=0.028) but not with IL-6. Platelet count was also associated with WC and waist-to-hip ratio (p<0.05). Haemoglobin and haematocrit were in consistent relationship with LDL-cholesterol (p<0.05). In conclusion, obesity was associated with higher WBC count and inflammatory parameters. There was also a positive relationship between WBC count and several inflammatory and metabolic risk factors in healthy women.Key words: Angiotensin Π, C-reactive protein, Interleukin 6, Obesity, White blood cell count  相似文献   
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Although evidence tends to suggest that high levels of lead exposure increase the risk of spontaneous abortion, we do not yet know whether moderate- to low-level exposure elevates risk. Among 351 women (aged 16 to 35 years, with single pregnancies) who were registered for a longitudinal study, 15 (4.3%) women experienced spontaneous abortion after the 12th week of gestation and before the 20th week. We collected participants' blood samples during the first trimester of pregnancy (8-12 weeks) for lead measurement by inductively coupled plasma-mass spectrometry. Mean ± standard deviation of blood lead was 3.8 ± 2.0 μg/dl (range 1.0-20.5 μg/dl) with a geometric mean of 3.5 μg/dl. Mean blood lead concentrations did not differ significantly between spontaneous abortion cases and ongoing pregnancies (3.51 ± 1.42 and 3.83 ± 1.99 μg/dl, respectively). The findings suggest that in apparently healthy women, low blood lead levels (mean < 5 μg/dl) measured in early pregnancy may not be a risk factor for spontaneous abortion.  相似文献   
50.

Background

The body mass index (BMI) is the most commonly used marker for evaluating obesity related risks, however, central obesity measures have been proposed to be more informative. Lipid accumulation product (LAP) is an alternative continuous index of lipid accumulation, which is computed from waist circumference (WC, cm) and triglycerides (TGs, mmol/l): (WC-65) ×TG (men) and (WC-58) ×TG (women). We sought in this study to assess if LAP can outperform BMI, waist-to-height-ratio (WHtR), or waist-to-hip-ratio (WHpR) in identifying prevalent and predicting incident diabetes.

Results

The cross-sectional analyses were performed on a sample included 3,682 men and 4,989 women who were not pregnant, aged ≥ 20 years. According to the age (≥ 50 and <50 years) - and sex-specific analyses, odds ratios (ORs) of LAP for prevalent diabetes were higher than those of BMI, WHpR, or WHtR among women, after adjustment for mean arterial pressure and family history of diabetes. The OR of LAP in old men was lower than those of other adiposity measures; in young men, however, LAP was superior to BMI but identical to WHpR and WHtR in identifying prevalent diabetes. Except in young men, LAP showed highest area under the receiver operating characteristic curves (AROC) for prevalent diabetes (P for trend ≤ 0.005).For longitudinal analyses, a total of 5,018 non-diabetic subjects were followed for ~6 years. The ORs of BMI, WHpR, and WHtR were the same as those of LAP in both sexes and across age groups; except in young men where LAP was superior to the BMI. AROCs of LAP were relatively the same as anthropometric adiposity measures.

Conclusions

LAP was a strong predictor of diabetes and in young individuals had better predictability than did BMI; it was, however, similar to WHpR and WHtR in prediction of incident diabetes.
  相似文献   
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