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101.
Apart from cannabis abuse in northern and southern Africa and khat chewing in north-eastern Africa, the history of drug abuse in Africa is relatively short. The abuse of drugs in Africa is nevertheless escalating rapidly from cannabis abuse to the more dangerous drugs and from limited groups of drug users to a wider range of people abusing drugs. The most common and available drug of abuse is still cannabis, which is known to be a contributing factor to the occurrence of a schizophrenic-like psychosis. The trafficking in and abuse of cocaine and heroin are the most recent developments in some African countries that had had no previous experience with these drugs. Efforts should be made to design and implement drug abuse assessment programmes to determine the real magnitude and characteristics of the problem and to monitor its trends. A lack of funds and a shortage of adequately trained personnel have made it difficult to implement drug abuse control programmes. In addition to formal drug control involving the implementation of legislation, there is an informal system of drug abuse control operating through the family, church, school, neighbourhood and work environment, as well as healthy recreational activities. It is suggested that efforts in African countries should be directed towards strengthening not only the formal drug control system but also informal control in order to compensate for the insufficient funds and the shortage of personnel trained in implementing formal drug control measures. It is very likely that the drug problems in African countries will worsen in future unless more effective measures are implemented to arrest the current situation.  相似文献   
102.
ABSTRACT The claims made for the contribution of Evolutionary Psychology to psychotherapy are questioned. The relevance of human evolutionary history is not disputed, but it is argued that insufficient account is taken of the unique features of human beings, that the polemical attacks made on the social and human sciences are irrational, that the hypothetical reconstructions of human evolution are frequently arbitrary and biased, and that the extent to which evolved innate'mentalities'are said to determine social roles ignores the evidence for the plasticity of human brains and for social influences in individual development. In its consistent bias in favour of innate rather than learned and culturally formed processes and in its language and assumptions EP underestimates the inherited and acquired capacities of human societies and individuals to change. It fails to take adequate account of the key evolutionary development whereby humans became symbol-making and symbol-using social animals whose individual psychological development involves processes, the understanding of which requires a new theoretical perspective. These features, combined with the absence of a clear model of practice, seriously limit the contribution of EP to psychotherapy.  相似文献   
103.
BACKGROUND: Allergen-specific immunotherapy is the only treatment for allergic disease providing long-lasting symptom relief. Currently, it is mainly based on the use of crude allergen extracts. The treatment may be improved by the use of genetically engineered allergens, hypoallergens, aiming at a more effective and safer therapy. OBJECTIVE: The aim of this study was to provide a rational design of hypoallergen candidates for immunotherapy by using structural information and knowledge of B and T cell epitopes of an allergen. METHODS: The three-dimensional structure of the major cat allergen Fel d 1 was systematically altered by duplication of selected T cell epitopes and disruption of disulphide bonds. Seven Fel d 1 derivatives were generated and screened for allergenic reactivity in comparison with recombinant Fel d 1 in competition-ELISA. The allergenicity was further evaluated in basophil activation experiments and T cell reactivity was assessed in a lymphoproliferation assay. RESULTS: Three out of seven Fel d 1 derivatives, with two duplicated T cell epitopes and one or two disulphide bonds disrupted, were carefully evaluated. The three derivatives displayed a strong reduction in allergenicity with 400-900 times lower IgE-binding capacity than recombinant Fel d 1. In addition, they induced a lower degree of basophil activation and similar or stronger T cell proliferation than recombinant Fel d 1. CONCLUSION: By a rational approach, we have constructed three Fel d 1 hypoallergens with reduced IgE-binding capacities and retained T cell reactivities. This strategy may be applied to any well-characterized allergen to improve immunotherapy for allergic patients.  相似文献   
104.
Intersexualität     
Zusammenfassung Intersexualität bezeichnet eine seltene Störung der somatosexuellen Differenzierung mit einer Inzidenz von etwa 2 pro 10.000 Geburten pro Jahr in Deutschland. Dahinter verbergen sich verschiedene Diagnosen einer vermehrten Virilisierung bei 46,XX-Karyotyp oder deutlich verminderter Virilisierung bei 46,XY-Karyotyp. Manchmal werden diese Störungen erst während der Pubertätsentwicklung entdeckt. Dann ist eine rasche Diagnostik zur Prognosestellung notwendig. Bei allen Jugendlichen mit Intersexualität muss das Management während der Pubertät viele Aspekte von der psychosexuellen Begleitung bis hin zur medizinischen Behandlung mit Hormonsubstitution oder Therapie und der Beratung hinsichtlich chirurgischer Maßnahmen enthalten.  相似文献   
105.
It is shown that with the holding potentials (Eh) ranging from -50 to -30 mV the amplitudes of the inward Ca current of identified neurons are significantly higher in old (20-24 months) Lymnaea stagnalis molluscs than in adult ones.  相似文献   
106.
107.
Two hundred and seventy-seven patients with advanced prostatic cancer were treated by either orchiectomy or oestrogen. During the 2-year follow-up period, the response to treatment was considered more favourable in the oestrogen group, and this response was particularly emphasised in patients with poorly differentiated tumour and metastases at the time of diagnosis. Further evaluations included the cardiovascular side effects of oestrogen therapy.  相似文献   
108.
109.
PURPOSE: Two experiments explored the extent to which induced blur, reduced luminance, and reduced visual fields affect drivers' steering performance in a driving simulator. METHODS: In experiment 1, ten young participants (M = 21.2 years) drove at approximately 89 km/h (55 mph) along a curvy roadway while being exposed to blur (0 to + 10 D), luminance (0.003 to 16.7 cd/m), and visual field (1.7 and 150 degrees) manipulations. In experiment 2, a new group of ten young participants (M = 18.5 years) drove while exposed to seven visual field sizes (1.7 to 150 degrees). RESULTS: Steering was sensitive to a reduced field size but not to the blur and luminance challenges. Acuity, on the other hand, was sensitive to the blur and luminance challenges but not to reduced field size. DISCUSSION: In healthy young drivers, steering performance is remarkably robust to severe blur and to extremely low luminances. These results support a key element of the selective degradation hypothesis advanced by Leibowitz and colleagues--that steering abilities are preserved at night even when the ability to recognize objects and hazards is not. Additional research should address the other element of this hypothesis--that drivers fail to appreciate the extent to which their visual abilities are degraded at night.  相似文献   
110.
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 23, No. 5, pp. 540–549, May, 1989.  相似文献   
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