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61.
Objective: Cigarette smoking is one of the major risk factors for coronary artery disease. However, chronic smoking has additional cardiac adverse effects independent of coronary atherosclerosis. We assessed the possible effects of chronic smoking on left and right ventricular (LV, RV) long-axis function using Doppler myocardial imaging (DMI). Methods: Forty otherwise healthy smokers (mean age = 26 ± 3 years) and 40 age-matched nonsmoking controls enrolled. Standard echocardiography protocol was followed by DMI. Peak systolic (VS), early (VE) and late diastolic (VA) velocities, peak systolic strain (S), and strain rate (SR) were measured from septal, lateral, and RV free walls. Results: The baseline characteristics of two groups were similar. There were significant differences regarding Doppler myocardial velocity, S, and SR indices. Septal VE (P < 0.04), S (P < 0.0001) and SR (P < 0.02) were significantly reduced in smokers. For both lateral and RV free wall, VS (P < 0.003, P < 0.002, respectively), VE (P < 0.0001, P < 0.002, respectively), S (P < 0.0001 for both), and SR (P < 0.0001, P < 0.002, respectively) were significantly reduced in smokers. There were significant correlations between the amount of smoking and septal, lateral, and RV free wall S and SR. Conclusions: Chronic cigarette smoking causes alterations in long-axis systolic and diastolic functions of right and left ventricles in healthy young subjects. These changes can be accurately detected with Doppler myocardial velocity and SR imaging.  相似文献   
62.

Background:

Psoriasis and seborrheic dermatitis are both chronic erythemato-squamous dermatoses that can involve the scalp. It may be difficult to differentiate these two diseases when there is isolated scalp involvement. Recently, trichoscopy is commonly used to differentiate noncicatricial alopecias including psoriasis and seborrheic dermatitis that can lead to telogen effluvium (TE).

Objectives:

The objective of this study is to evaluate the trichoscopic figures that may help to differentiate scalp psoriasis and seborrheic dermatitis.

Materials and Methods:

Thirty one with scalp psoriasis and 112 patients with seborrheic dermatitis were enrolled. Trichoscopic examinations were performed using a videodermatoscope (MoleMax 3®). Trichoscopic findings of scalp psoriasis and seborrheic dermatitis were compared with each other, with 100 healthy individuals and with other noncicatricial alopecias including female androgenetic alopecia (FAGA) (n: 138), male androgenetic alopecia (n: 63), FAGA of male pattern (FAGA.M) (n: 5), alopecia areata (39), TE (n: 22) and trichotillomania (n: 4).

Results:

Atypical red vessels, red dots and globules (RDG), signet ring vessels (SRV), structureless red areas and hidden hairs (HH) were statistically more common in psoriasis while twisted red loops and comma vessels (CV) in seborrheic dermatitis. RDG were considered as the characteristic videodermatoscopic figure for psoriasis and arborizing red lines and CV for seborrheic dermatitis. In comparison with previous reports, our study yielded two new trichoscopic structures supporting the diagnosis of psoriasis; HH and SRV. Besides, according to our study, CV were described for the first time in seborrheic dermatitis and considered to be specific for seborrheic dermatitis.

Conclusion:

This study confirmed that trichoscopy might be useful in differentiating scalp psoriasis and seborrheic dermatitis from each other and from other noncicatricial alopecia with three trichoscopic structures as HH, SRV and CV.  相似文献   
63.
A differential-pulse voltammetric method was developed for the determination of amlodipine based on the oxidation of the dihydropyridine group on the surface of glassy carbon electrode under stationary and rotating conditions. The experiments were conducted in a supporting electrolyte consisting of 0.2 MKCl, 0.1 Mphosphate buffer, and 10 % (v/v) methanol during investigation of initial potential and pH effects. No adsorption effect was observed on using an initial potential of 0 mVand the supporting electrolyte solution at pH 5.5 under both stationary and rotating conditions. The factor affecting the voltammetric current was diffusional in the range of 200-1000 rpm for rotating, and 2-40 mV s(-1) for stationary conditions up to a concentration of 0.04 mg mL(-1) amlodipine. The limit of detection (LOD) and the limit of quantitative (LOQ) for the rotating and stationary techniques were found to be 0.004 and 0.0072 mg mL(-1) (for S/N = 3.3) and LOQ 0.012 and 0.022 mg mL(-1) (for S/N = 10), respectively. The proposed method was applied to the tablets containing amlodipine and according to the statistical evaluations acceptable results were obtained at the 95 % probability level.  相似文献   
64.
BACKGROUND: Although transthoracic needle biopsy (TNB) has been the preferred method for the diagnosis of anterior mediastinal masses, it has inherent limitations in accuracy. In particular, lymphoma and thymoma are diagnosed less reliably using needle biopsy. Videothoracoscopy has been advocated as an alternative method for diagnosis. Our goal was to assess the usefulness of extended cervical mediastinoscopy (ECM) in the diagnosis of anterior mediastinal masses. METHODS: The ECM technique was performed in 9 patients in whom TNB and Tru-cut biopsies had been inefficient for histologic diagnosis. All lesions were in the anterior mediastinum. Extended cervical mediastinoscopy was carried out using the same incision as in a standard cervical mediastinoscopy and dissection was performed behind the sternum as previously published. Mean operative time was 50 minutes (range 40 to 70 minutes) and mean hospital stay was 8 hours (range 5 to 36 hours). RESULTS: Diagnosis of lymphoma in 4 cases, thymoma in 3 cases, and thymic hyperplasia in 2 cases were obtained by ECM. In 1 of 2 patients with suspected thymoma who underwent resectional surgical procedures, final histologic diagnosis was non-small cell lung carcinoma. There was no surgical mortality or intraoperative complication. One patient had minimal pneumothorax requiring no intervention. CONCLUSIONS: We conclude that ECM in the diagnosis of anterior mediastinal masses is technically feasible and provides an alternative to the conventional approaches in patients with paraaortic or aortopulmonary masses.  相似文献   
65.
Cytokine interferon gamma (IFN-gamma) is pivotal in the defence against viruses and intracellular pathogens and an age-related decreased IFN-gamma production may explain the increased infectious disease morbidity and mortality in the elderly. Therefore, we performed a series of clinical experiments evaluating the influence of age and health status on IFN-gamma production following in vitro stimulation with influenza vaccine or endotoxin. Both healthy and frail elderly people produced significantly lower amounts of IFN-gamma following ex vivo stimulation with influenza vaccine or endotoxin. We conclude that ageing is accompanied by a decreased capacity to produce IFN-gamma. This may explain the increased incidence and case-fatality caused by viruses and intracellular pathogens in the elderly.  相似文献   
66.
Background: Helicobacter pylori infection has been proposed to have a role in the development of atherosclerosis preceded by endothelial dysfunction. The aim of the present study was to determine if a relationship exists between H. pylori infection in childhood and endothelial dysfunction and level of high‐sensitivity C‐reactive protein (hsCRP). Methods: Between October 2003 and November 2004, 28 subjects who were anti‐H. pylori IgG‐positive and 25 who were anti‐H. pylori IgG‐negative were included in the study. Mean ages of the H. pylori‐positive and negative groups were not significantly different. Endothelial functions were evaluated on Doppler ultrasonography of the brachial artery. Percent ratio of the change in systolic diameter during hyperemic phase to the basal diameter was evaluated. Each subject’s serum was tested for hsCRP, homocysteine and lipids. Results: Percent ratio of the change in systolic diameters during hyperemic phase to the basal diameter was not significantly different between the H. pylori‐negative and ‐positive groups (P > 0.29). Mean levels of hsCRP were also not significantly different (1.48 ± 1.8 g/dL vs 2.35 ± 3.33 g/dL; P > 0.24). Similarly, serum levels of lipids and homocysteine were not significantly different (P > 0.05 for all lipids). Conclusions: Non‐invasive techniques used in the present study were not indicative of early findings of atherosclerosis in H. pylori infection during childhood. Further studies are required to evaluate the relationship between early endothelial dysfunction and H. pylori infection in children with cardiovascular risk factors.  相似文献   
67.
Fever of unknown origin (FUO) is a diagnostic challenge for the practising physician. Detailed medical history, physical examination, non-invasive laboratory tests, and radiologic examinations compose the first level in the diagnostic approach to the FUO. When a diagnosis cannot be established with these procedures, some invasive diagnostic techniques and finally exploratory laparotomy are performed. Although advanced diagnostic measures and imaging-guided less invasive procedures have decreased the need, laparotomy remains as a final diagnostic method for FUO cases. In this study we evaluate the role and importance of laparotomy in the diagnosis of our FUO cases. In 17 out of 126 patients (8 male, 9 female, the median age 35.8 years) hospitalized in our clinic between 1982 and 2002 with the diagnosis of FUO, the diagnosis was established by laparotomy. The diagnosis was made directly in 13 patients, and indirectly (by excluding other diseases) in 2 patients. In several FUO series, the contribution of laparotomy to the diagnosis of FUO was reported as 27-100%. This rate was found to be 88% in the present study. During laparotomy on 17 cases, tissue samples were taken from spleen, liver, intra-abdominal and mesenteric lymph nodes. Pathologic examination of these tissue samples revealed miliary tuberculosis in 4; non-Hodgkin's lymphoma in 3; Hodgkin's lymphoma in 3; liver tumour in 1; hairy cell leukemia in 1; peritonitis carcinomatosis in 1. In the patients with miliary tuberculosis, the liver (3) and/or spleen (2), and/or lymph node (3) revealed caseating granulomas. Laparotomy diagnosed 3 of 5 cases whose abdominal ultrasonography and computerized tomography were normal. In conclusion, although advanced diagnostic methods decreased the need for laparotomy in FUO, if non-invasive and invasive diagnostic measures fail, laparotomy may contribute to the diagnosis. The selection of the patient and the timing are important for laparotomy.  相似文献   
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70.
Purpose Intraperitoneal chemotherapy (IPCT) delivers higher local concentrations of cytotoxic drugs than intravenous (IV) chemotherapy, but it can adversely affect the healing of intestinal anastomoses if given in the early postoperative period. Intestinal anastomotic leakage is a serious surgical complication. Experimental and clinical studies have shown that the local administration of granulocyte macrophage-colony stimulating factor (GM-CSF) improves would healing. Therefore, we evaluated the effects of locally applied GM-CSF on anastomotic wound healing in rats treated with intraperitoneal mitomycin-C immediately after surgery.Methods We performed colon anastomoses in albino rats, which were then divided into three treatment groups. Group A was a control group that received no treatment, Group B was given intraperitoneal mitomycin-C postoperatively, and Group C was given intraperitoneal mitomycin-C with a local injection of GM-CSF postoperatively. We measured bursting pressures and hydroxyproline content, and histologically examined the resected anastomoses on postoperative day (POD) 3.Results Anastomotic healing was impaired after intraperitoneal mitomycin-C, but this was overcome by the injection of GM-CSF into the perianastomotic area.Conclusion Local GM-CSF administration counteracts the detrimental effects of intraperitoneal mitomycin-C treatment on intestinal anastomoses in rats.  相似文献   
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