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161.
1. The effects of dl -tetrahydropalmatine (dl -THP) on cardiovascular function and hypothalamic release of monomines were assessed in rats under urethane anaesthesia. 2. Intravenous administration of dl -THP (1-10 mg/kg) produced hypotension, bradycardia, a decrease in hypothalamic serotonin and noradrenaline release and in increase in hypothalamic dopamine release in rats. 3. Intrahypothalamic administration of DOI (a serotonergic 5-HT2 receptor antagonist) or apomorphine (a dopamine D2-receptor agonist) produced the opposite effects and reversed dl -THP-induced hypotension and bradycardia. 4. The data suggest that dl -THP acts through the 5-HT2 and/or D2-receptor antagonism in the hypothalamus to induce hypotension and bradycardia in rats.  相似文献   
162.
Aim. Detection of methylation in the p16 gene, an inhibitor of cyclin D-dependent protein kinase, as a new tumor marker for early detection of esophageal squamous cell carcinoma (ESCC) in DNA derived from blood and serum. Method. A large family with clustering of ESCC was assessed in Khorasan province in northeastern Iran. The family had three histologically proven cases of ESCC in two consecutive generations and several other deceased cases with histories of ESCC. DNA from blood of 28 living family members in three consecutive generations, 30 sporadic ESCC cases (from serum, blood, and tumor tissues), and 30 healthy volunteers (from blood) were examined for the methylation status of p16 promoter using methylation-specific PCR (MSP). Results. Aberrant p16 promoter methylation was found in 64.3% (n=28) of ESCC family members and none (n=30) of our normal volunteers. Five of the 28 family members with esophageal cancer symptoms had negative endoscopy results for ESCC, while four of these members had p16 hypermethylation in their blood. The family members with negative endoscopy and positive p16 promoter methylation are being monitored closely for signs of ESCC development through regular check-ups and chromoendoscopies. In sporadic ESCC in northeastern Iran, 73.3% (n=30) of tumor tissue samples had p16 hypermethylation. Serum and blood samples from the same patients showed p16 hypermethylation in 26.6% and 43.3% of the samples, respectively. Conclusion. Aberrant p16 methylation may be a valuable diagnostic tool as a tumor marker for the early identification of individuals in high risk ESCC families.  相似文献   
163.

Background

The objective of this study was to determine the prevalence of cystic echinococcosis (CE) in Qom Province, central Iran using ELISA test.

Methods

Overall, 1564 serum samples (800 males and 764 females) were collected from selected subjects by randomized cluster sampling in 2011-2012. Sera were analyzed by ELISA test using AgB. Before sampling, a questionnaire was filled out for each case. Data were analyzed using Chi-square test and multivariate logistic regression for risk factors analysis.

Results

Seropositivity was 1.6% (25 cases). Males (2.2%) showed significantly more positivity than females (0.9%) (P= 0.03). There was no significant association between CE seropositivity and age group, occupation, and region. Age group of 30-60 years encompassed the highest rate of positivity. The seropositivity of CE was 2.1% and 1.2% for urban and rural cases respectively. Binary logistic regression showed that males were 2.5 times at higher risk for infection than females.

Conclusion

Although seroprevalence of CE is relatively low in Qom Province, yet due to the importance of the disease, all preventive measures should be taken into consideration.  相似文献   
164.
Paget's disease of the nipple is characterized by the presence of Paget's cells in the epidermis of the nipple or areola. Two case reports of Paget's disease are described and used to highlight unusual features of the disease. The literature on the radiographic and pathologic findings of this disease is reviewed.  相似文献   
165.
166.
Background Positive patch test results to transition metals (nickel sulphate, palladium chloride, cobalt chloride and potassium dichromate) alone and in combinations with one another are well known. Numerous factors may play a role in isolated and concurrent sensitization to these allergens. Objetive This study aims to describe the isolated and concurrent prevalence of sensitization to transition metals in a Spanish Dermatology Department, between 2000 and 2005, and to determine the prevalence of concomitant positive patch test reactions to different transitional metals. Patients/methods Patients (N= 1092) were tested with the standard series of our Allergic Contact Unity, using a standardized technique. Data from these patients were recorded on a computer entry form and analysed. Statistical analyses to evaluated associations of metal contact allergy were performed, and we evaluated the concordance among these associations of transition metals. Results Three hundred twenty (29.3%) patients reacted positively to nickel, 128 (11.7%) to palladium, 118 (10.8%) to cobalt and 82 (7.5%) to chromium. The prevalence of positive reactions to metals was 32.4%. The association of palladium–nickel was the most frequent, with an acceptable concordance (k= 0.46). Conclusion This study illustrates that concomitant positive patch test reactions to different transitional metals are frequently seen in patients with allergic contact dermatitis. Our results reflect the high prevalence of sensitization to nickel in Spain.  相似文献   
167.
In a phase IIIb clinical trial of the ultrasound contrast agent Levovist® (Schering AG, Berlin, Germany), the role of Levovist® in the management of patients with clinically suspected hepatocellular carcinoma (HCC) was evaluated and its efficacy was assessed. The assessment included the duration of diagnostically usable Doppler signal enhancement, and safety and tolerance of intravenous administration. All patients with clinically suspected hepatocellular carcinoma were referred for Doppler sonographic examination over a 5-month period and lesions with absent or suboptimal Doppler signals were included in the trial. A total of 300 mg/mL in concentration (8.5 mL) of Levovist® was administered through a peripheral vein while Doppler signal intensity in the lesion, based on a visual score, was recorded. Blood pressure and pulse were recorded before and after injection. Thirty-eight patients were examined, of which 29 were included in the trial. The lesions were subsequently proven histologically to be 19 HCC, one cholangiocarcinoma, two regeneration nodules and one colonic metastasis. For six patients in whom histological proof was not available, the diagnosis of HCC was suggested based on markedly elevated serum alpha-fetoprotein levels. All but one (96%) of the 25 HCC demonstrated increased Doppler signal after Levovist®. There were no Doppler signals before and after Levovist® injection in three non-HCC lesions (two regeneration nodules and one colonic metastasis). Two patients (6.9%) suffered minor adverse reactions of nausea and vomiting. The results show that Levovist® is safe and is able to improve lesion characterization and increase diagnostic confidence of hepatocellular carcinoma by enhancing tumour vascularization Doppler signal intensity.  相似文献   
168.
胰岛素样生长因子-1(IGF-1)和胰岛素可能是肠道生长的重要调节因子。为了研究肠细胞萎缩和再生期间小肠IGF-1受体(IGF-IR)和胰岛素受体(IR),我们比较了禁食72小时和肠内再喂养24~72小时大鼠空肠IGF-IR和IR表达的指标。禁食引起肠萎缩,血浆胰岛素和IGF-1浓度降低以及空肠IGF-1信使RNA(mRNA)水平的明显降低,再喂养可逆转这些改变。禁食明显增加胰岛素与空肠特异性地结合,IR含量(达对照组的230%)和9.6kb和7.4kbIRmRNA转录本水平(分别达对照组的202%和218%)。再喂养时,这些IR指标迅速降到对照组水平。禁食时IGP-IR(用Scatchard分析)和IGF-1-RmRNA无明显的改变。再喂养后的前24小时间11-kbIGF-IRmRNA转录本明显增加(达对照组水平166%),IGF-IR数量增加3倍。我们的结论是:大鼠空肠的IR和IGF-IR受到不同营养物利用状态的调节。再喂养时空肠IGF-1和IGF-IR表达的向上调节表明,IGF作用途径在对肠内营养物产生肠道营养反应的过程中起作用。  相似文献   
169.
170.
We report a case of human nasal nosocomial myiasis in a 69-year-old rural man with numerous live maggots in nostrils. The patient was admitted in Emergency Ward due to dyspnea. After 72 hours the companion of patient discovered larva. The presence of the third instar larva indicated that the infestation was not more than three days. The collected instars were cleared, fixed and morphological studies then were carried out precisely and the larva was identified as Lucilia sericata.  相似文献   
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