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31.
32.

Purpose

The aim of this study was to investigate whether polyunsaturated phosphatidylcholine. (PPC) pretreatment has any protective effect on gastric mucosal damage induced by cold-restraint stress (CRS) in rats.

Methods

Forty swiss albino rats were divided into 3 groups. Group 1 (n = 10) was control, group 2 (n = 15) was stress ulcer, and group 3 (n = 15) was PPC-treated rats with stress ulcer. Stress ulcer was induced by the cold-restraint method for 4 hours at 4°C after a starvation period of 72 hours. In the group 3 rats, PPC treatment was started 10 days before stress at a dose of 100 mg/d by oral route. Rats were terminated, stomachs were excised. Macroscopic ulcer index (UI), gastric tissue malondialdehyde (MDA) and superoxide dismutase (SOD) activities, plasma total nitrite, and erythrocyte catalase (CAT) concentrations were assayed.

Results

Histopathologic examination showed a stress ulcer index of 0.12 ± 0.19 mm in the treatment group and 23.6 ± 8.97 mm in the stress ulcer group (P < .001). Tissue MDA and SOD concentrations were higher in the stress ulcer group than in the treatment group, the differences were statistically significant (P < .001). Plasma NO3+ NO2 levels were higher (P< .005) and CAT levels were lower (P < .001) in the nontreatment group. There were no significant differences with respect to Ul, MDA, and SOD levels among the control and treatment groups (P > .05).

Conclusions

These results suggest that pretreating rats with PPC inhibits cold-restraint stress-induced gastric mucosal injury and might be useful in preventing stress-induced stomach ulcers.  相似文献   
33.
Early diagnosis of perforated appendicitis is important for reducing morbidity rates. The aim of this study was to determine the value and utility of plasma D-lactic acid levels in identifying the type of appendicitis. In this clinical study, plasma D-lactic acid levels were assessed in 44 consecutive paediatric patients (23 with acute appendicitis, 21 with perforated appendicitis) before laparotomy. D-lactic acid levels were determined by an enzymatic spectrophotometric technique using a D-lactic acid dehydrogenase kit. Patients with perforated appendicitis had higher D-lactic acid levels (3.970 +/- 0.687 mg/dL) than patients in the control group (0.478 +/- 0.149 mg/dL) and patients with acute appendicitis (1.409 +/- 0.324 mg/dL; p < 0.05). For a plasma D-lactic acid level greater than 2.5 mg/dL, the sensitivity and specificity of the D-lactic acid assay were 96% and 87%, respectively. The positive predictive value was 87%, the negative predictive value was 96%, and the diagnostic value was 91%. These results suggest that the measurement of plasma D-lactic acid levels may be a useful adjunct to clinical and radiological findings in distinguishing perforated from acute non-perforated appendicitis in children.  相似文献   
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Aase-Smith syndrome type II is rare in childhood and there are few reported cases. Here, we report an 8-month-old boy with congenital red cell aplasia and triphalangeal thumbs. In addition to thumb anomalies, he presented with growth failure, hypertelorism and novel osseous radiologic abnormalities, large fontanelles and micrognathia as extraordinary. Some clinical symptoms had complete clinical remission with deflazacort treatment.  相似文献   
37.
In this study, the authors examined the concentrations and mineralogical analyses of asbestos, and investigated mesothelioma risk in southeastern Anatolia, Turkey. They used a gravimetric dust sampler to collect samples from 2 villages and 2 asbestos mines (1 active). Samples were then evaluated by an X-ray diffractometer and an electron microscope. The authors found high concentrations of asbestos in an active mine (4.9 fibers[f]/cm3) and at a house that was plastered with asbestos (1.24 f/cm3) and had a very active population. They found a low concentration (0.0042 f/cm3) in indoor measurements taken in Armutova village, and an even lower concentration (0.000081 f/cm3) in the inactive mine environment. Outdoor measurements included a low concentration of 0.007 f/cm3 in the village environment, and a high concentration of 1.17 f/cm3 on the mine road during the passing of a sheep herd. The people in the region are continuously exposed to asbestos during normal activities. This cumulative exposure to asbestos carries sufficient risks for mesothelioma development.  相似文献   
38.
The aims of this study were firstly to investigate the fluoride-releasing characteristics of two composite resins (Tetric and Valux Plus), two polyacid-modified resin composites (Compoglass and Dyract), and conventional glass-ionomer cement (Ceramfil beta). The second aim was to assess the fluoride uptake and subsequent release from the same range of materials. Fifteen discs (6 mm diameter and 1.5 mm height) were prepared for each material. Each disc was immersed in 4 ML of deionized water within a plastic vial. The release of fluoride was measured daily at 1, 2, 3, 4, 5, 15, 30 and 60 days. After daily fluoride release was measured for 60 days, samples were refluoridated in 1000-ppm sodium fluoride (NaF) solutions (pH 6.6) for 10 min and fluoride release was measured daily for a total of 5 days. The release of fluoride from aesthetic restorative materials was measured by using specific fluoride electrode and an ionanalyser. Results were statistically analysed by two-way repeated measure ANOVA and Duncan's multiple range test. The results revealed that all fluoride-containing materials (Ceramfil beta, Compoglass, Dyract, Tetric) released fluoride initially and the release was greatest at the first day. At any time during the test period Ceramfil beta released the most and Valux Plus did not release any detectable fluoride (P < 0.01). Sample exposures to 1000 ppm NaF solution increased the 24-h fluoride release from all fluoride-containing materials. This difference lasted only 24-48 h after exposure. Ceramfil beta had a tendency to recharge not seen with the other materials (P < 0.05).  相似文献   
39.
Fifty-three consecutive children ages 6 to 14 with femur fractures treated with early percutaneous intramedullary fixation were evaluated retrospectively. The operation was performed within 24 hours in 50 patients and in the remainder after 48 hours. All patients were mobilized and allowed full weight-bearing in a functional brace in the early postoperative period. The average hospital stay was 4 days. The average follow-up was 24 months. There were no significant intra- or postoperative complications. An average overgrowth of 1.8 mm was measured using scanogram 24 months after surgery. In the authors' experience, this technique is highly effective for the treatment of children 6 to 14 years old with femur fractures. The main advantages of this method are early weight-bearing, immediate mobilization, short hospitalization, and fewer complications.  相似文献   
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