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811.
Hunteria umbellata (K. Schum.) Hallier f. (family: Apocynaceae) is reputed for the folkloric management of labour, pain and swellings, stomach ulcers, diabetes, obesity, and anaemia, with no scientific report of its toxicity and reversibility profile. The present study was, therefore, aimed at investigating the in vivo toxicity and reversibility profile of the aqueous seed extract of Hunteria umbellata (HU). The acute oral and intraperitoneal toxicity studies of HU were determined in Swiss albino mice while its 90-day oral toxicity and toxicity reversibility profile on anthropometric, biochemical, haematological and histopathological parameters were also assessed using standard procedures. Results showed that the LD50 values for the acute oral and intraperitoneal toxicity studies for HU were estimated to be 1000 mg/kg and 459.3 mg/kg, respectively. Visible signs of immediate and delayed toxicities including starry hair coat, respiratory distress, and dyskinesia were observed. For the chronic oral toxicity study, HU administered for 90 days produced significant (p<0.001) reductions in the weight gain pattern and significant (p<0.001) and dose related increases in the relative weights of liver, stomach, spleen, testis, lungs and heart, at the 100 and 500 mg/kg of HU. Chronic HU treatment also produced significant (p<0.05, p<0.001) dose related reductions in the serum levels of fasting blood glucose, bicarbonate, urea and creatinine while causing non-significant (p>0.05) alterations in the serum levels of sodium, potassium, alaninine transaminase, aspartate transaminase, alkaline phosphatase, total and conjugated bilirubin, total protein and albumin. Also, chronic oral treatment with HU produced significant (p<0.05, p<0.01, p<0.001) and dose-related increases in the red cell count, packed cell volume, haemoglobin concentration, platelet count, total leucocyte count and lymphocyte differential while producing significant (p<0.05) reductions in neutrophil and granulocyte differentials. HU also produced histological features of proliferations of the stomach epithelia, lung tissues, splenic white and red pulps, and testicular spermatogenic series. Following 14 days of oral toxicity reversibility test, there was no significant (p>0.05) reversal in the serum levels of the biochemical and haematological parameters investigated, including the HU-induced histological lesions.Overall, results of this study showed that HU has a relatively low oral toxicity profile but its prolonged use, particularly, at high doses should be with great caution.Key words: Hunteria umbellata, Toxicity and reversibility profile, Haematology, Liver and Renal function tests, Histopathology, Rodents  相似文献   
812.
Objective: The aim of this study is to assess the correlation between traditional cardiovascular risk factors and elevated plasma tHcy level in Nigerian hypertensive. Methods: Thirty-six hypertensive patients were recruited with 36 age and sex-matched controls. The age, sex and anthropometric measurements including height, weight and body mass index (BMI) were taken. Plasma total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides and tHcy were analyzed. The results of the two groups were compared. Results: The mean total cholesterol and LDL- C were significantly higher in the subjects than in the controls (P = 0.01 and 0.03 respectively). On the other hand, means of HDL-C and triglycerides were not significantly different between the two groups (P =0.06 and 0.68 respectively). Mean total plasma tHcy was ( 12.95 ±4.9) μmol/L in hypertensive patients when compared with ( 11.29 ±3.6) μmol/L in the controls (P = 0.09) , however the mean tHcy was significantly higher in hypertensive patients who had stroke or myocardial infarction than those without these complications (one way Anova F = 3.63, P = 0.04). Significant positive correlation was seen between tHcy and systolic blood pressure, diastolic blood pressure, BMI and LDL-C. Conclusion : The study suggests that elevated plasma tHcy may predict occurrence of cardiovascular complications in hypertensive individuals.  相似文献   
813.
Understanding the effect of radiation on tissue, the principles of dosimetry and fractionation have led to the acceptance and adoption of radiation as a standard treatment option for cancer. Delivered in staged and scheduled aliquots, radiation will break nucleic strands and cause cellular death. In general, radiation therapies are delivered using external techniques (external beam and intensity-modulated therapy). One of the limitations of such external techniques is that of nontarget radiation. That is, despite best efforts to collimate and reflect radiation beams to a small target, nontarget radiation and a dose to areas outside the tumor remains a distinct possibility. With the advent of radioembolization using Yttrium-90 microspheres (90Y), the radiation source is delivered optimally through a novel mechanism: directly into the blood vessel providing flow to the tumor. This revolutionary approach capitalizes on the basic principles of tumor hypervascularity, concentrating radiation within that tumor, while at the same time minimizing the risks of nontarget radiation. This review elaborates on this technology.  相似文献   
814.

Introduction  

Extracorporeal membrane oxygenation (ECMO) is a supportive cardiopulmonary bypass technique for babies with acute reversible cardiorespiratory failure. We assessed morbidity in ECMO survivors at the age of five years, when they start primary school and major decisions for their school careers must be made.  相似文献   
815.
Aim:  To report the stability of parent-perceived child irregular eating from 6 months to 14 years of age and to investigate a predictive model inclusive of child and parent factors.
Methods:  Of the 7223 singleton children in a birth cohort, 5122 children were re-interviewed at 5 years and 4554 for the 14-year analysis. Information was obtained from structured interviews including questions answered by parents of the child at birth, 6 months, 5 years and 14 years; and by teenagers at age 14 years and from physical measures of the child. The mother's perception that the child was an irregular eater at age 14 years was the major outcome variable of interest.
Results:  Approximately 40% of irregular eaters at age 5 will still be irregular eaters at age 14 years. This was not related to maternal education or socio-economic class. Significant at multivariate analysis were infant feeding problems and the children's ability to regulate their sleep and mood. Significant maternal factors were greater age, not feeling positive about the baby and persistent maternal anxiety during the child's early years.
Conclusion:  Irregular eating behaviour displays considerable continuity from childhood to mid-adolescence. Independent contributions to this behavioural phenotype include child biological and psychological factors and maternal anxiety during the child's early years.  相似文献   
816.
A simple co-culture bioassay system was used to investigate whether or not the anatomical origin affected the ability of epithelial cells from the human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also used to identify some of the factors which may be involved in the regulation of sperm-epithelial interactions in vitro by comparing different tissue culture models and assessing the effect of oestradiol concentration. Epithelial explants harvested from different regions of human uterine tubes were co-incubated with a known concentration of motile donor spermatozoa. All results were adjusted to reflect a standard sperm concentration of 5 x 10(6)/ml. More spermatozoa associated per field of isthmic compared to ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/- SEM); n = 36, P < 0.05, ANOVA] and cells from post-menopausal patients had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0, ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage nor addition of mid-cycle concentrations of 17beta-oestradiol (750 pmol/l) affected the number of spermatozoa which bound to epithelium from either tubal region. In addition, the number of spermatozoa which bound per field of polarized explants was greater (P < 0.05) than that bound to dissociated primary and passaged epithelial cell monolayers. This report is the first to provide evidence suggestive of a role for sperm- epithelial binding in the formation of an isthmic sperm reservoir in the human uterine tube. Results also indicate that oestrogen is not involved in the regulation of these interactions, and that cell polarity is an important factor for such associations in vitro.   相似文献   
817.

Background

Perception of midline diastema differs among individuals and cultures. To some, it is a feature of beauty, while to others it is aesthetically appalling. From a scientific point of view, midline diastema is a deviation from normal adult dentition. It is not uncommon among some African natives to find individuals demanding for artificially created midline diastema from dental practitioners.

Objective

To present a rare case of pulpal necrosis involving maxillary and mandibular central incisors as a result of poorly executed teeth modification in a bid to create upper and lower midline diastemata.

Result

A 23-year old lady presented with history of spontaneous, sharp, persistent pain associated with palatal swelling and discharging sinus of two weeks duration in relation to maxillary central incisors (11, 21). The complaint was preceded by a history of recurrent pain in relation to 11, 21, 31 and 41 which started soon after obtaining artificially created maxillary and mandibular midline diastemata from a dental quack. Periapical x-ray revealed periapical radiolucency in relation to 21 and 41. Vitality test confirmed necrotic pulp in the lower central incisors. The affected teeth were scheduled for root canal therapy (RCT) and porcelain fused to metal crown. The RCT of 11 and 21 had been completed but further treatment stalled due to financial constraint.

Conclusion

This is a case of obsession for midline diastema, poor dental health education, and illegal dental practice.  相似文献   
818.
BACKGROUND: The study aimed to determine whether allergic conditions accompany analgesic intolerance. METHODS: A total of 132 analgesic-intolerant patients with bronchial asthma admitted to the adult allergy unit from January 1991 to October 1997 and 103 patients with bronchial asthma randomly selected from among the asthmatics referred to our department between January and October 1997 were enrolled in the study. Those having analgesic intolerance and bronchial asthma were accepted as group I; patients having only asthma were accepted as group II. A standard questionnaire was completed for all the patients. Physical examination, routine skin prick tests, determination of total IgE levels and blood type, and oral analgesic provocation tests were also performed. RESULTS: The results showed that some allergic conditions were significantly more common in group I (22.7% and 7.8% for food allergy/intolerance [P<0.05], 16.7% and 7.8% for antibiotic allergy, 16.7% and 2.9% for dermographism, 9.8% and 1.0% for metal allergy, and 9.1% and 1.0% for chronic urticaria for groups I and II, respectively [P<0.001]). In addition, the mean of the total IgE level in the serum was higher in group I than group II (77.6 and 53.7 IU/ml; P<0.05), and the cumulative analgesic consumption was more in group I (14.2+/-17.1 and 9.1+/-12.5 boxes; P<0.05). CONCLUSIONS: Dermographism; chronic urticaria; antibiotic, metal, and food allergy; high levels of total IgE; and a high amount of cumulative analgesic consumption may be the conditions accompanying analgesic intolerance in asthmatics.  相似文献   
819.
In a double-blind, block randomized study we investigated the effect of dietary supplementation with eicosapentaenoic acid in patients with psoriasis. The experimental group received 10 g of fish oil daily containing approximately 1.8 g eicosapentaenoic acid, while the controls were given an isoenergetic amount of olive oil. We found no significant change in the clinical manifestations of psoriasis in either group after 8 weeks of treatment. In the experimental group, the amount of n-3 fatty acids in serum phospholipids was significantly increased at the end of trial as compared to pre-treatment values, whereas the level of n-6 fatty acids was decreased.  相似文献   
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