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61.
This cross-sectional study is aimed at the identification of patterns in the utilization of health care services in Pau da Lima, a neighborhood in the city of Salvador, Bahia. In 1992, a household survey was carried out with 384 families selected through a random cluster sampling design. In each household, the family head or a surrogate informant was asked to answer a questionnaire about their use of any type of health care in the last month. From the total of 1,887 individuals, 236 reported at least one visit to health facilities during the referent period This means an estimated prevalence of health services utilization of 12.5%. With regard to the type of services, 25.9% of all visits were made to public sector facilities. Attendants were mainly women (73.7%) from 15 to 29 years of age. The main reason reported for the choice of the health facility was availability (63.7%), and the major reason for seeking health care was disease-related conditions (75.7%), rather than preventive procedures. These findings may result from the still unfinished process of distritaliza??o(district allocation of services), which is evident in the lack of health services' infrastructure or coverage, as well as in persistent organizational problems. These issues may lead the population living in the respective district to seek health care outside the assigned catchment area. The authors discuss these findings in the context of the expansion of the private sector in the health area and the financial collapse of the public budget in Brazil.  相似文献   
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Differentiation of the non-dividing trypomastigote form of Trypanosoma cruzi, the causative agent of Chagas disease, to the dividing amastigote form normally occurs in cytoplasm of infected cells. Here we show that calyculin A. a potent inhibitor of protein phosphatases 1 and 2A, induces at pH 7.5 extracellular transformation of long slender trypomastigotes to round amastigote-like forms which acquire characteristic features observed after the normal differentiation process: repositioning and structural changes of the kinetoplast, release of surface neuraminidase, and expression of amastigote-specific epitopes. Calyculin A inhibits parasite phosphatases and changes in the phosphorylation of specific proteins occur during the transformation process. As an exposure of trypomastigotes to calyculin A concentrations as low as 1 nM and for only 1-2 h is sufficient to induce transformation, the inhibition of calyculin A-sensitive phosphatase(s) appears to play a major role in initiating the trypomastigote differentiation.  相似文献   
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This study investigates the effects of intracerebroventricular injection of selective agonists and antagonists of tachykinin NK(3)receptor on performance of mice in the elevated plus-maze test. Mice were treated with either vehicle or 1, 10, 100 or 500 pmol of neurokinin B or senktide ([succinil-Asp(6), MePhe(8)]substance P(6-11), a natural and synthetic selective NK(3)receptor agonists, respectively. Other mice received similar doses of [Trp(7)beta-Ala(8)]NKA(4-10)or SR 142801 ((S)-N-(1-(3-(1-benzoyl-3-(3, 4-dichlorophenyl)-piperidin-3-yl)propyl)-4-phenyl-piperidin- 4-yl)-N-m ethylacetamide) tachykinin NK(3)receptor selective peptide and non-peptide antagonists, respectively. Senktide significantly increased the frequency of entries and the time spent in the open arms, which is compatible with an anxiolytic action. Neurokinin B treatment did not alter the plus-maze parameters in a significant way. Conversely, the NK(3)peptide antagonist [Trp(7)beta-Ala(8)]NKA(4-10), but not SR142801 non-peptide antagonist, showed a reverse effect, i.e. an anxiogenic profile of action, reducing the frequency and the time spent in the open arms. Co-injection of either senktide plus [Trp(7)beta-Ala(8)]NKA((4-10)), or senktide plus SR 142801, blocked the effects promoted by senktide, indicating that centrally-administered NK(3)receptor agonists and antagonists can modulate experimental anxiety.  相似文献   
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Osteoradionecrosis (ORN) of the mandible is one of the most dreaded complications in the treatment of cancer of the head and neck. If conservative and surgical treatment have not been successful, very often the only remaining solution is surgical intervention into the bone continuity of the mandible. In a group of eight patients suffering from ORN of the horizontal ramus of the lower jaw we gathered first experiences with hyperbaric oxygen therapy in combination with an operation to preserve the bone continuity (debridement of the bone and closing of the soft tissues). Hyperbaric oxygen was given during a time span of 13 to 52 hours (average: 36 hours). It was only with those two patients who received more than 50 hours of hyperbaric oxygen therapy that we achieved our aim of "total recovery from ORN of the mandible while saving its bone continuity". In one case where there was no clinically manifest recidivation of the tumour, the tumour showed rapid growth under hyperbaric oxygen therapy. In three cases partial resection of the mandible had to be performed without reconstruction for cure of ORN. Despite the loss of bone continuity these patients are only slightly cosmetically impaired and nutrition causes no problems. In two patients ORN still exists. On the basis of our first experiences with a small group of patients and in accordance with various publications, we conclude that hyperbaric oxygen therapy is a significant adjunct in the treatment of the mandible if a well-founded diagnosis is established and if it is followed by a well-adjusted therapy.  相似文献   
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We studied the clinical, EEG and MRI findings in 19 patients with epilepsy secondary to congenital destructive hemispheric insults. Patients were divided in two groups: 10 with cystic lesions (group 1), and 9 with atrophic lesions (group 2). Seizure and EEG features, as well as developmental sequelae were similar between the two groups, except for the finding that patients of group 2 more commonly presented seizures with more than one semiological type. MRI showed hyperintense T2 signal extending beyond the lesion in almost all patients of both groups, and it was more diffuse in group 2. Associated hippocampal atrophy (HA) was observed in 70% of group 1 patients and 77.7% of group 2, and it was not correlated with duration of epilepsy or seizure frequency. There was a good concordance between HA and electroclinical localization. The high prevalence of associated HA in both groups suggests a common pathogenesis with the more obvious lesion. Our findings indicate that in some of these patients with extensive destructive lesions, there may be a more circumscribed epileptogenic area, particularly in those with cystic lesions and HA, leading to a potential rationale for effective surgical treatment.  相似文献   
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The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections.  相似文献   
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