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41.
A long-term controlled field experiment on the interactions of the populations of Biomphalaria glabrata (target population) and B. straminea (competitor) was carried out in the county of Alhandra, state of Paraíba, Brazil, during the period 1980 through 1989. Results obtained in the current paper show that the snail B. straminea has strong competitive advantages over B. glabrata. In six out of nine streams the native population of B. glabrata were totally excluded and replaced by B. straminea. There is evidence showing that seasonal dryness has marked influence on the phenomenon studied in this paper. In all the streams were B. straminea already predominated, return of B. glabrata was never observed.  相似文献   
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43.
Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented.  相似文献   
44.
The effects of a gestational exposure of 80 rats Wistar EPM-1 to nicotine and undernutrition was examined. The weight and histological alterations on the liver and lungs was evaluated on the rats and their offspring. A significantly lower weight gain, including liver and lung weight, was observed in nicotine exposed groups. There was no alteration of the placental weight. Decidual necrosis and hepatic congestion was frequent in the rats. Lung emphysema was found in the neonates.  相似文献   
45.
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   
46.
Gynecomastia is a benign condition that frequently occurs in the male breast gland; however, the cytogenetic data on this entity are very limited. To our knowledge, three cases have been reported in the literature, and the only one with an abnormal karyotype had a concomitant breast carcinoma. In this study we report clonal chromosomal alterations in a gynecomastia sample without any signs of adjacent malignant tissue. The nonrandom abnormalities observed were a deletion of 12p, monosomies of chromosomes 9, 17, 19, and 20, and the presence of a marker chromosome. Most of these alterations have been previously described in the literature in other breast lesions, including benign and malignant (male and female) tumors, indicating their recurrence and nonrandomness in abnormal processes of the mammary gland.  相似文献   
47.
The authors describe the results of an application of the surgical technique called ASTRA (anterior sagittal transrectal approach) in a 16-year-old girl with recurrent urethro-vaginal fistula. The young girl had a posttraumatic urethro-vaginal fistula. It recurred after 4 operations by a direct vaginal approach before definitive correction with the ASTRA. Three years after the operation the patient has remained well with complete healing and no fistula recurrence confirmed by a voiding cystourethrogram and urodynamic and rectal manometric tests. This report suggests that ASTRA is a useful method of treating acquired or developmental anomalies of the perineal region.  相似文献   
48.
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   
49.
Lewis (LEW) is an inbred strain of rats frequently used as an animal model of autoimmune diseases. However, there is evidence that some lines of LEW rats develop autoimmune diseases more readily than do other LEW rat lines. Because the hypothalamus-pituitary-adrenal system is involved in the pathophysiology of these diseases, we compared two LEW lines (SsNHsd and HANRijHsd) in their behavioural and neuroendocrine response to stress. In addition, we studied the psychostimulant effects of acute and repeated amphetamine in these two LEW rat lines. HAN rats were less active in the open field test and showed faster habituation of novelty-induced locomotion. The acoustic startle response was lower in HAN than in SSN rats, whereas prepulse inhibition of the startle response was greater in the HAN than in the SSN LEW subline. Moreover, HAN rats showed impaired acquisition of the two-way active avoidance response relative to SSN rats. The psychostimulant effects of acute amphetamine were smaller in HAN rats. Following repeated injections of amphetamine, behavioural sensitization to the psychostimulant effects of amphetamine was more pronounced in HAN than in SSN rats. Basal concentrations of serum corticosterone did not differ between the two rat lines. Following stress, however, HAN rats showed slightly higher corticosterone secretion than SSN rats. Our results show that two sublines of the LEW inbred strain of rats show profound behavioural differences which are only marginally paralleled by differences at the level of the HPA system.  相似文献   
50.
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