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The aim of this study was to evaluate the biochemical changes in cobalt-exposed rats and to investigate the potential role of Tunisian propolis against the cobalt-induced renal damages. Twenty-four pregnant Wistar rats were divided into four groups and were treated as follows: group 1 (control) received distilled water; group 2 received 350 ppm of CoCl2 in drinking water; group 3 received 350 ppm CoCl2 in drinking water and a propolis-supplemented diet (1 g/100 g of diet); group 4 received a propolis-supplemented diet (1 g/100 g of diet) without cobalt. In the cobalt group, a significant decrease in body, absolute and relative weights was noted when compared to controls. The administration of cobalt to pregnant rats from the 14th day of pregnancy until day 14 after delivery resulted in an increased level of renal malondialdehyde, a decreased renal content of glutathione and antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase in lactating rats and their pups. A statistically significant increase in plasma urea and creatinine serum levels was seen in treated female rats and their pups. Histopathologically, the cobalt-administration induced degenerative changes in the kidney of lactating rats and their pups. When compared with cobalt-treated rats, those receiving the propolis supplementation (along with cobalt-treatment) had lower malondialdehyde levels, higher antioxidant activities and the cobalt-related histopathological changes in the kidneys were at lower severity.Our results suggested that the propolis might be a potential candidate agent against cobalt-induced nephrotoxicity in adult and juvenile rats when administered to female rats during the late pregnancy and the early postnatal period.  相似文献   
3.
This article proposes a Fuzzy Second Order Integral Terminal Sliding Mode (FSOITSM) control approach for DFIG-based wind turbines subject to grid faults and parameter variations. Since traditional terminal sliding mode control (SMC) suffers from singularity, a novel integral terminal sliding manifold is proposed to eliminate chattering and improve the wind turbine's performance in the presence of faults and disturbances. A fuzzy system is proposed to auto-tune the controllers' gains and ensures the invariance of the sliding surfaces even under heavy uncertainties, thus further improving the reliability and performance of the proposed controller. The performance of the proposed approach was assessed under various operating conditions. A comparison analysis with a standard SMC approach as well as the state of the art in voltage sag mitigation was also carried over. Reliability, robustness, and power availability under faulty grid conditions are among the main features of the proposed approach. In addition, the proposed approach exhibited chattering free dynamics and enabled the finite time convergence of the sliding manifold and overcame the singularity problem associated with standard TSMC.  相似文献   
4.
Interpretation of densitometric results requires a comparison with reference bone mineral density (BMD) values of normal age and sex-matched persons. Thus the aim of this study was to determine these values for healthy Tunisian women, to estimate the prevalence of osteoporosis and to compare our findings with other populations. A cross-sectional study of 1378 Tunisian women aged between 20 and 96 years was carried out using DXA (GE-Lunar Prodigy). Subjects with suspected conditions affecting bone metabolism were excluded. Measurements were taken at the lumbar spine and femoral neck. These values were expressed at T-scores, with reference to the mean BMD values of the group aged 20–40 years. The peak bone mass, estimated in this age group was 1.174 + 0.127 g/cm2 at the lumbar spine and 1.016 ± 0.118 g/cm2 at the femoral site. It was attained respectively within the age of 25 years and 36 years. For both sites, the expected decline in BMD was shown when the successive age groups [40–49 years] and [50–59 years] were compared. Bone loss was rapid during the first 5 years after menopause. Thereafter BMD declined slowly but continually. The prevalence of osteoporosis in the women over 50 years of age, taking account of peak bone mass observed in our cohort, was 23.3% at the spine and 17.3% at the femoral neck with a combined prevalence of 23.4%. These rates attained respectively 30.4%, 11.8% and 32.9% when we considered the Italian values, which demonstrate the variability of osteodensitometric depending to the reference population adopted.  相似文献   
5.
Gibberellic acid (GA3), a plant growth regulator, was largely used in agriculture of many countries including Tunisia. However, its potential hazardous effects on human health were relatively unexplored. The purpose of this study was to investigate the effects of GA3 on hepatic function in female rats and their pups. Animals were given daily 200 ppm GA3 in drinking water from the 14th day of pregnancy until day 14 after delivery. It was found that GA3 induced liver damages as evidenced by the elevation of plasma aminotransferases (ALT, AST), lactate dehydrogenase activities, bilirubin and albumin levels. Hepatotoxicity was objectified by the significant increase of malondialdehyde (MDA) level and a decrease of antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione content in liver of suckling pups and their mothers. Impairment of hepatic function corresponded histologically. We have observed blood vessels congestion and leucocytes infiltration, which were more pronounced in hepatocytes of dams than those of suckling pups.Results of this current study suggest that exposure rats to GA3 induces hepatotoxicity and histopathological changes in liver of female rats and their progeny.  相似文献   
6.
Autosomal dominant cerulean cataracts (ADCC) have previously been mapped to two loci: one on chromosome 17q24 and the other on chromosome 22q11.2-q12.2, which includes the beta-B2 crystallin (CRYBB2) candidate gene. Using polymorphic markers in these regions (D17S802, D17S836, D17S1806 and CRYBB2, D22S258) for linkage analysis, we excluded these loci in a large Moroccan family presenting with an unusual form of ADCC with early onset of lens opacities and rapid evolution. This finding confirms the clinical and genetic heterogeneity of autosomal dominant congenital cerulean cataracts.  相似文献   
7.
Osler Weber Rendu Disease is an hereditary haemorrhagic télangectasia habitually revealed by reccurent bleeding (epistaxis). Hepatic involvement in Osler disease is found in 8 to 31%, manifested by cholestasis. We report an original observation of a cholangitis revealing Osler disease.  相似文献   
8.
Hydatic pulmonary embolism: complication of a cardiac hydatic cyst:a case report hydatic cardiac cyst is a rare condition and represents only 0.5 to 2% of all visceral localisations of the hydatid disease. We reported a 28 year old patient with a multiple hydatic pulmonary embolism caused by the rupture of a hydatic cyst of the interventricular septum. The diagnosis was established by transthoracic echocardiography and CT Scan. Surgery was performed without delay and the outcome was good after a five month follow-up. This case illustrates the diagnostic value of the non invasive imaging means in hydatic cyst of the heart and underlines the importance of surgery realized before complications occur.  相似文献   
9.
The survey was performed during the month of March 1998 and concerned 9 ICUs located in teaching hospitals. To be included each ICU had to MV for more than 12 hours were included in the study and had a 28 day follow-up in the ICU or until hospital discharge. Collected parameters were indications of MV, modalities of MV and of weaning, complication and outcome at hospital discharge. Assist-control ventilation was the most used ventilation modality (69.8%). Weaning of MV was performed in 63% of the study patients and was based on a once-a-day attempt of spontaneous breathing through a T-piece (59.5%) and a combination of intermittent mandatory ventilation with pressure support (IMV-PS: 27%) or pressure support alone (11.2%). Mean length of hospital stay was 19.7 +/- 15.9 days of which 11.6 days were spent in the ICU. Fifty nine patients (54%) were alive at discharge form the ICU of whom 4 ultimately died during their hospital stay. MV practice as well as ICU facilities are not homogenous in Tunisia. Recommendations and guidelines should be built in order to standardize MV practice in Tunisia.  相似文献   
10.
The aim of this study is to report the results, the complications and limits of laparoscopy in patients with tuberculous peritonitis. In a retrospective study of 163 laparoscopy realized from 1970 to 1998. All the patients had exsudative ascites with predominantly of lymphocytes. Miliary nodules were found in 87% of cases, adhesions between the peritoneum and organs were found in 69% of cases and congestion in 63% of cases. Laparoscopically guide peritoneal biopsies detected caseating granulomas in 87% of cases. Laparoscopic appearance of the peritoneum mimicking a carcinosis in 15% of cases. One patient had complication as a bowel perforation. Miliary nodules and adherences are the more frequent appearances into peritoneal cavity in tuberculous peritonitis. With peritoneal biopsies, laparoscopy is always the best method for definitively and rapidly diagnosis of tuberculous peritonitis.  相似文献   
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