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91.
Ten protein coding loci (6‐PGD, A1‐AT, ACP1, CaII, ESD, GC, GPX1, Hbβ, PGM1, and TF) were analyzed in the Mbenzele Pygmies from the Central African Republic. The frequency data were used to calculate the genetic distances between Mbenzele Pygmies and other African groups. In the principal coordinate plot of FST genetic distances, the Mbenzele cluster together with other Pygmies of the western cluster, the Biaka from C.A.R., Gielli from Cameroon, and Babinga from Congo. By contrast, they are considerably distanced from other Pygmy groups of the eastern cluster (Twa from Rwanda, Mbuti from Zaire). Genetic distances obtained using protein loci were compared with those based on microsatellite loci. The two distance matrices are insignificantly correlated (r = 0.268; one tail probability = 0.332), and the main difference is in the higher genetic affinity between the Mbenzele and Biaka Pygmies observed at the protein level. Although reasons underlying the discrepancy between inter‐populational variation at protein and DNA loci are not established with certainty, the comparison suggests that the genetic distance between the Mbenzele and Biaka Pygmies at microsatellite loci could have been shaped by genetic drift. Am. J. Hum. Biol. 14:9–14, 2002.© 2002 Wiley‐Liss, Inc.  相似文献   
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We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
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A competitive enzyme immunoassay of histamine in foodstuffs has been developed using a monoclonal antibody against a histamine‐benzoquinone adduct. In this assay, histamine present in food samples was treated with 1,4‐benzoquinone to form histamine‐benzoquinone by a simple and quick reaction and a histamine‐benzoquinone‐horse‐radish peroxidase conjugate was used as the labelled hapten. The apparent association constant (Ka) of the antibody used was 3.6 ×106 l/mol and Gibbs’ energy of the immune complex formation has been estimated to find the optimal incubation time of the assay. The method enabled determination of histamine in fish, cheese, wine and beer at a concentration as low as 7 ng/ml with an accuracy of ± 15%. The recovery of the immunoassay was 88.9–114%. Cross‐reactivities of histidine, tyramine, tryptamine and its derivatives were lower than 0.001% and did not affect the assay.  相似文献   
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The present paper deals with a developing training element in cognitive behaviour therapy (CBT), the self‐practice of therapeutic techniques and the self‐exploration of the person of the therapist. Initially, the current status of this training element in CBT is discussed, and a short note on its terminology is presented. Then an overview of the most important objectives of self‐practice and self‐reflection in CBT, and the concepts and methods of practice of this element is given. The concepts focus on two major aims, the self‐exploration of the person of the therapist within and beyond his or her therapeutic practice, and the self‐application of therapeutic techniques (= self‐practice). In the second part of the paper empirical studies related to the outcome of self‐reflection and self‐practice on the development of the therapist and her or his therapeutic practice are reviewed. The few empirical studies show that trainees experience in their own view substantial professional and personal gains from this training tool, with the professional impact being more important than the personal one. The most important outcomes evaluated by subjective data from the trainees are improvements in self‐insight and self‐awareness and a better understanding of the therapist's role and the therapeutic change process. Additionally, a better understanding of CBT methods and of general therapeutic skills, such as empathy and role‐taking‐competencies, are reported by the trainees. The paper comes to the conclusion that self‐exploration and self‐practice are important components of CBT training. Consequences and recommendations for its integration into training courses for CBT are discussed as well as the necessity for more research in this area. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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There are significant variations among countries in the incidence of brain abscess. We report here 26 cases of brain abscess treated at the Neurosurgery Department of King Faisal University and Dammam Central Hospital Saudi Arabia over a six year period (1982–1988). This is 2.3% of total admissions to the two neurosurgery departments serving a population of approximately 1.2 million in the same period.Young males were most often affected (M/F ratio 3.3:1; 31% were less than 15 years old, 46% aged between 15–39 years, and 23% older than 40 years). Streptococcus was found to be the most common microorganism (38.4%). Mixed infection was seen in 15.3%, and sterile abscesses were found in 11.5% of the patients after aerobic and anaerobic cultures of the pus. Chronic otitis media and paranasal sinusitis predisposed the patients to abscess formation in 57.6% of the cases. The temporo-parietal area was the commonest site. Epilepsy was a complication in 30.7% of our patients, and the mortality rate was 15.3%.  相似文献   
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Khellin (CAS 82-02-0) and methoxsalen (CAS 298-81-7) were examined in male albino rats to evaluate their ability to modify serum lipoprotein cholesterol. Clinical chemistry parameters were also measured to obtain information indicative of possible drug toxicity. The drugs were evaluated in four-week double dose studies. After four weeks at 0.45 mg/100 mg b.wt. for khellin and 0.27 mg/100 g b.wt. for methoxsalen, per day, both drugs significantly lowered low density lipoprotein cholesterol, high density lipoprotein cholesterol and total cholesterol. Very low density lipoprotein cholesterol and triglycerides were not changed. No apparent toxicity was observed as clinical chemistry parameters and body weights were not different compared to control values. Similar results were observed with a lower dose of khellin (0.23 mg/100 g b.wt./d). A dose of 0.13 mg/100 g b.wt./d of methoxsalen had no observable effect in this study. Confirmation of the hypocholesterolemic activity of khellin and methoxsalen in this study enhances the therapeutic potential of these compounds against atherosclerosis.  相似文献   
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