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991.
Eighty-four postmenopausal women who were randomly allocated to one of four groups, completed a 1 year follow-up. The first group (n = 20) received 0.625 mg/day conjugated estrogens cyclically (CE; 25 days/month). The second (n = 23) received 0.625 mg/day of CE continuously, and the third (n = 17) received 50 micrograms/day of transdermal 17 beta-estradiol cyclically (24 days/month). All these groups also received 2.5 mg of medroxiprogesterone acetate sequentially for the last 12 days of hormone replacement therapy, while the fourth group (n = 24) constituted a treatment-free control group. Dual photon absorptiometry was carried out before therapy and was repeated after 1 year. Serum calcium, phosphate and osteocalcine levels, and the urinary calcium/creatinine and hydroxyproline/creatinine ratios, were measured prior to treatment and 6 and 12 months thereafter. All treatment groups showed an increase in bone mineral content. This increase was higher in the continuous CE treatment group (4.4%, P less than 0.05) and in transdermal group (7.1%, P less than 0.01). Concomitant biochemical effects at 6 and 12 months, reduction in urine calcium and hydroxyproline, reduction in blood calcium, phosphate and osteocalcine, were compatible with the observed effects on bone mineral.  相似文献   
992.
993.
Experimental models of hypersensitivity pneumonitis are important tools for the study of the pathogenesis of this disease. In this paper we review the characteristics of the main animal models developed until now. The HP models in rats seem to be particularly appropriate for studying pigeon fancier's disease and the HP induced by chemicals, as well as for studying mediators of acute lesions induced by immunocomplexes. However, the HP models developed in rats are of less value in the evaluation of other aspects of the pathogenesis of this clinical entity in humans. The murine models of HP offer several advantages: the ease and simplicity of intranasal administration, the ability to produce acute and subacute pulmonary lesions similar to those found in humans, the possibility of reproducing lesions similar to those of nonaffected exposed subjects and the possibility of pharmacologically modulating the process. Their disadvantages lie in the different pulmonary lymphocyte response and the difficulty in reproducing a model of chronic fibrosis. The HP models in rabbits are extraordinarily useful for evaluating the immunological mechanisms through which subjects repeatedly exposed to the antigen do not develop clinical manifestations. However, the rabbit has several immunological differences when compared to humans, and the effect of some immunomodulators in this animal is different. The models of HP in guinea-pigs have as advantages the ease in handling the animals, the possibility of pharmacological manipulation, and the ability to induce an acute phase that is very similar to that observed in humans. The drawback, however, is the low lymphocyte response and the striking eosinophilic reaction that contrast with the bronchoalveolar data found in HP in humans. In conclusion, there is no ideal model to reproduce all the findings observed in humans, suggesting that the experimental animal and the method of developing HP should be selected on the basis of concrete research aims.  相似文献   
994.
In 1980-1990 in the Strakonice district parallel serological examinations, using the Sabin-Feldman test (SFT) and complement fixation test (CFT), were made in 2,758 blood donors for the presence of antibodies against toxoplasmosis. The total number of examinations was 8,245. In the course of the mentioned time interval no significant increase or decrease of the serological prevalence occurred. During the first examination of blood donors the SFR antibodies (titre > or = 4) were detected in 45.4%, CFT (titre > or = 10) in 24.6% donors. 651 blood donors were examined four times or more frequently after 6-month intervals. 22.9% donors lacked antibodies (SFT and CFT) permanently, a rarely present low titre was recorded in another 22.9% donors, a repeated low titre in 43.6% and a repeatedly encountered medium or high titre in 10.6% of blood donors.  相似文献   
995.
996.
Albendazole is considered to be the drug of choice for treatment of parenchymal brain cysticercosis. Its efficacy, however, for treatment of subarachnoid cysticerci has not been established, to our knowledge. In this study, we treated four patients who had giant subarachnoid cysticerci with albendazole at daily doses of 15 mg/kg of body weight for 8 days. Computed tomographic studies showed that all cysts disappeared 3 months after the end of treatment. This was associated with marked clinical improvement in every case. Our results indicated that albendazole is highly effective for treatment of this form of the disease.  相似文献   
997.
Within Mexico's floristic abundance, plants with curative properties are outstanding due to their popularity in handling several illnesses, a fact that becomes specially important for the social groups of the tropical regions. In this paper the results of an ethnobotanical study carried out in 57 rural populations from the Mexican states of Oaxaca, Veracruz and Puebla are presented; questionnaire and interview methods were applied, with special attention to the use of plants for medical purposes. The most relevant results were: the taxonomic determination of 237 vegetal species from which 399 curative products are obtained, in order to combat 57 illnesses, the most frequent of which are those related to the digestive system, the skin, the reproductive system and those of supernatural origin, which can only be treated by the use of plants in special ceremonies known as 'limpias', due to their peculiar condition.  相似文献   
998.
999.
We have evaluated the clinical toxicity of Epirubicin 80 mg/m2 i.v., every 3 weeks in 58 patients with FIGO III-IV endometrial adenocarcinoma or squamous uterine cervix carcinoma. The median age of the whole group was 59 years (37-77); 37 patients were previously treated with radiotherapy and two with cisplatin based chemotherapy. The median KI at entry was 80. A total of 308 courses of chemotherapy were administered with a median of 5 per patient. Overall toxicity data shows that this dose level is associated with mild haematological toxicity with only two cases having grade 3 (WHO) leukopenia. Nine patients suffered emesis in spite of prophylactic therapy and were classified as grade 3. One case presented grade four diarrhoea but the relation with the antineoplastic treatment was uncertain. One woman with hepatic dysfunction at entry had grade 3 leukopenia, developed pneumonia and died. The median total cumulative dose of EPI was 360 mg/m2 (160-880) with 19 cases exposed to cumulative doses higher than 550 mg/m2. Congestive heart failure was not observed. Our data confirm the safety of EPI at these dose levels and suggest the possibility of developing new trials with higher doses of this anthracycline analog.  相似文献   
1000.
Authors analyse 1792 fractures in children, treated during 10 years in their Department and distributed in age groups. They take the part of conservative treatment of the majority, about two third, of fractures in childhood. They consider as operative indication certain forms of epiphyseal injuries, the dislocated intraarticular fractures, the unstable fractures, certain cases of polytrauma and the open fractures.  相似文献   
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