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151.
PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P 相似文献   
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153.
It is currently accepted that vinil infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptom-, indicative of utopic disease and EBV antibodies in 353 children aged from I month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by en/. yme imimmoassay. Dividing ihe study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s. d.) was, in total, more frequent in the EBV negative (32. 9%) than in the positive subjects (27. 6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels.  相似文献   
154.
The intestinal ecosystem in chronic functional constipation   总被引:3,自引:0,他引:3  
Chronic functional constipation is common in infants, and the bacterial composition of stools in this condition is not known. The study aims were to: (i) investigate the composition of the intestinal ecosystem in chronic functional constipation; (ii) establish whether the addition of the water-holding agent calcium polycarbophil to the diet induces an improvement in constipation; and (iii) determine the composition of the intestinal ecosystem after the use of this agent. In total, 42 children (20F, 22M; mean age: 8.6±2.9y) were studied. Twenty-eight children with functional chronic constipation without anatomical disorders were treated double-blind in random sequence for 1 month with an oral preparation of calcium polycarbophil (0.62g /twice daily) or placebo. Intestinal flora composition was evaluated by standard microbiological methods and biochemical assays on faecal samples collected before and after treatment. Fourteen healthy children were studied as controls. The results show that (i) the constipated children presented a significant increase in clostridia and bifidobacteria in faeces compared to healthy subjects-different species of clostridia and enterobacteriaceae were frequently isolated; no generalized overgrowth was observed; Clostridia outnumbered bacteroides and E. coli mean counts by 2-3log, while bacteroides and E. coli counts were similar (5-6 log10/g fresh faeces); these intestinal disturbances could be defined as a dysbiosis, i.e. a quantitative alteration in the relative proportions of certain intestinal bacterial species. (ii) Clinical resolution of constipation was achieved only in 43% of treated children and an improvement in 21% (one bowel movement every 2 d). (iii) Calcium polycarbophil treatment induced no significant changes in the composition of the intestinal ecosystem, nor in blood chemistry parameters.  相似文献   
155.
156.
Rodents are particularly prone to acquire associative memories during early stages of life. Yet, very little is known about how ethanol interacts with simultaneous associative learning acquired during postabsorptive periods. We have recently observed that preweanling rats avoid lemon odor previously paired with the intraoral infusion of a sapid sweet solution, a result likely to be caused by aversive consequences inherent to this procedure. Two experiments were conducted to analyze the effects of acute ethanol upon the acquisition of this avoidance response. Fourteen-day-old Wistar rats were intragastrically administered with ethanol (0.0, 0.25, 0.5, or 1.25 g/kg) and then exposed for 5 min to a lemon-scented chamber while being intraorally infused with sucrose (12% vol/vol). Four of such pairings were conducted immediately after ethanol administration. Control pups experienced these stimuli in an unrelated fashion. On postnatal day 15 animals were tested in a 5-min, two-way odor-preference test. Pups administered with vehicle during the acquisition phase exhibited a strong aversion to the lemon odor relative to control subjects. This avoidance response was reduced in pups that received 0.5 and 1.25 g/kg doses, whereas it completely vanished in those that received 0.25 g/kg dose. In a second experiment it was observed that, 10 min after the administration, blood ethanol concentrations attained with the 0.25, 0.5, and 1.25 g/kg doses were 11, 39, and 83 mg%, respectively. These data indicate that a very low dose of ethanol is able to counteract early aversive associative learning, a result likely to be mediated by anxiolytic properties of ethanol.  相似文献   
157.
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.  相似文献   
158.
The mechanisms involved in the association between air pollution and increased cardiovascular morbidity are not fully understood. The objective of this study was to test the hypothesis that fine particulate matter (PM(2.5)) induces systemic inflammation and vasoconstriction of small arteries in the lung and heart of rats. Thirty-eight healthy Wistar rats were anesthetized, intubated, and submitted to the instillation of 1 ml of distilled water diluted in the following solution: blank filter, 100 microg and 500 microg of PM(2.5). PM(2.5) was collected in glass fiber filters with a high-volume sampler. The animals were sacrificed 24 h after instillation when blood, heart, and lung samples were collected for morphological and wet-to-dry weight ratio analysis. PM(2.5) consisted of the following elements: sulphur, arsenic, bromine, chlorine, cobalt, iron, lanthanum, manganese, antimony, scandium, and thorium. Total reticulocytes significantly increased at both PM(2.5) doses (p < 0.05) while hematocrit levels increased in the 500 microg group (p < 0.05). Quantification of segmented neutrophils and fibrinogen levels showed a significant decrease, while lymphocytes counting increased with 100 microg of PM(2.5) (p < 0.05). A significant dose-dependent decrease of intra-acinar pulmonary arteriole lumen/wall ratio (L/W) was observed in PM groups (p < 0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500 microg group (p < 0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 microg group (p < 0.001). In conclusion, fine environment particles in the city of S?o Paulo promote pulmonary and cardiac histological alterations. Pulmonary vasculature was markedly affected by particle instillation, resulting in significant vasoconstriction in healthy rats.  相似文献   
159.
目的:与亮脯利特比较,醋酸甲孕酮皮下注射(DMPA-SC104)治疗子宫内膜异位症的有效性和安全性。设计:3期多中心、随机、评价者盲法、对照比较试验。机构:加拿大和美国的临床试验点。患者:274例手术诊断的子宫内膜异位症妇女。干预:每3个月肌注DMPA-SC(104mg)或亮脯利特(11.25mg),共6个月。治疗后随访12个月。主要观察指标:5种子宫内膜异位症症状或体征的减轻(痛经、性交困难、盆腔痛、盆腔触痛、盆腔硬化);骨密度(BMD)改变、低雌激素的症状、出血及体重的变化。结果:DMPA-SC104,在治疗末(6个月)减轻5种子宫内膜异位症症状或体征的4种,在12个月随访末(18个月)减轻全部5种症状,与亮脯利特统计学上效果相当。DMPA-SC104组患者显示在6个月较亮脯利特有更少的BMD损失,在随访的12个月又回到基线水平。  相似文献   
160.
Bothrops jararacussu myotoxin I (BthTx-I; Lys 49) and II (BthTX-II; Asp 49) were purified by ion-exchange chromatography and reverse phase HPLC. In this work we used the isolated perfused rat kidney method to evaluate the renal effects of B. jararacussu myotoxins I (Lys49 PLA2) and II (Asp49 PLA2) and their possible blockage by indomethacin. BthTX-I (5 microg/ml) and BthTX-II (5 microg/ml) increased perfusion pressure (PP; ct120=110.28+/-3.70 mmHg; BthTX I=171.28+/-6.30*mmHg; BthTX II=175.50+/-7.20*mmHg), renal vascular resistance (RVR; ct120=5.49+/-0.54 mmHg/ml.g(-1)min(-1); BthTX I=8.62+/-0.37*mmHg/ml g(-1)min(-1); BthTX II=8.9+/-0.36*mmHg/ml g(-1)min(-1)), urinary flow (UF; ct(120)=0.14+/-0.01ml g(-1)min(-1); BthTX I=0.32+/-0.05*ml g(-1)min(-1); BthTX II=0.37+/-0.01*ml g(-1)min(-1)) and glomerular filtration rate (GFR; ct120=0.72+/-0.10 ml g(-1)min(-1); BthTX I=0.85+/-0.13*ml g(-1)min(-1); BthTX II=1.22+/-0.28*ml g(-1)min(-1)). In contrast decreased the percent of sodium tubular transport (%TNa(+); ct(120)=79,76+/-0.56; BthTX I=62.23+/-4.12*; BthTX II=70.96+/-2.93*) and percent of potassium tubular transport (%TK(+);ct120=66.80+/-3.69; BthTX I=55.76+/-5.57*; BthTX II=50.86+/-6.16*). Indomethacin antagonized the vascular, glomerular and tubular effects promoted by BthTX I and it's partially blocked the effects of BthTX II. In this work also evaluated the antibacterial effects of BthTx-I and BthTx-II against Xanthomonas axonopodis. pv. passiflorae (Gram-negative bacteria) and we observed that both PLA2 showed antibacterial activity. Also we observed that proteins Also we observed that proteins chemically modified with 4-bromophenacyl bromide (rho-BPB) decrease significantly the antibacterial effect of both PLA2. In conclusion, BthTx I and BthTX II caused renal alteration and presented activity antimicrobial. The indomethacin was able to antagonize totally the renal effects induced by BthTx I and partially the effects promoted by BthTx II, suggesting involvement of inflammatory mediators in the renal effects caused by myotoxins. In the other hand, other effects could be independently of the enzymatic activity of the BthTX II and the C-terminal domain could be involved in both effects promoted for PLA2.  相似文献   
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