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991.
The maculata group currently comprises two species of Triatominae, Triatoma maculata and Triatoma pseudomaculata, which share morphologic and chromatic characteristics. In order to clarify the systematic status of these two vectors of Trypanosoma cruzi and to infer their evolutionary relationships, we performed an enzymatic, morphometric and cytogenetic comparison of them, also taking into account two sister species not included in the group (T. arthurneivai and T. wygodzinskyi). According to our results, T. maculata and T. pseudomaculata belong to distinct evolutionary lineages. Similarly, T. arthurneivai topotypes from Minas Gerais form an independent isolated group by morphometrics. Our results also support the specific status of the Triatoma population from São Paulo State (formerly referred to T. arthurneivai), and suggest the possibility that it is T. wygodzinskyi. Finally, we suggest that only the arboricolous T. pseudomaculata from northeast Brazil and the rupicolous sister species originated from São Paulo State should be classified together in the same group.  相似文献   
992.
SETTING: Rio de Janeiro City, Brazil. OBJECTIVE: To evaluate the effect of directly observed therapy (DOT) on treatment success, by comparing the treatment success rates between patients treated under DOT with those who received self-administered therapy (SAT). DESIGN: A longitudinal study in a cohort of tuberculosis (TB) patients. Of 9929 new pulmonary TB cases, 1190 (12%) were treated under DOT and 8739 (88%) under SAT. All patients received a three-drug regimen consisting of rifampicin (RMP), isoniazid (INH) and pyrazinamide for 2 months followed by 4 months of RMP and INH. RESULTS: Patients under DOT were more likely to convert to sputum-negative at the end of the second month than those treated under SAT (86.3% vs. 61.9%, P < 0.001). DOT alone was significantly associated with successful treatment (OR 1.6, 95%CI 1.37-1.86, P < 0.001), even when controlled by sex, age and positive smear or culture at enrollment (OR 1.56, 95%CI 1.33-1.82, P < 0.001). CONCLUSION: This pilot DOTS implementation phase showed that DOT is highly effective and feasible in a large urban centre of a developing country.  相似文献   
993.
994.
In June 1996 in the state of Oaxaca, Mexico, larvae of the mosquito species Aedes aegypti were exposed to infective preparasites of the nematode Romanomermis culicivorax, Ross and Smith, in the laboratory and in the field. For the laboratory experiments larvae in instars I-IV were used; they had been collected in natural reservoirs. The laboratory experiments were carried out in triplicate, with 100 larvae of each larval stage per experiment. Three preparasite application dosage ratios were tested: 5, 10, or 15 preparasites per mosquito larva. For the field studies 13 A. aegypti outdoor breeding sites were used, with larvae in instars I-IV and a 15:1 preparasite dosage ratio. With the laboratory experiments, an increase was observed in the average infestation of the larvae as the preparasite application ratio was increased from 5:1 to 15:1. With a 10:1 ratio, the rates of parasitism were 100%, 100%, 85%, and 74% in the larvae in instars I, II, III, and IV, respectively; for the 15:1 preparasite ratio, parasitism rates were 100%, 100%, 90%, and 79%, respectively. The field tests with the 15:1 preparasite dosage ratio in the 13 outdoor reservoirs produced parasitism rates of 80% to 98%, thus demonstrating the susceptibility of this species of mosquito to parasitism by R. culicivorax in Oaxaca, Mexico.  相似文献   
995.
A Pacheco  A Perpi?á  L Escribano  I Sanz  C Bellas 《Chest》1992,102(1):296-297
A patient with mediastinal EP with extension to pleural spaces and subsequent pleural effusion is described. The finding of many plasma cells in pleural fluid led to diagnosis. Similar histologic findings such as multiple myeloma and immunoblastic lymphoma were ruled out by clinical approach and immunochemistry, respectively. This pleural effusion represents the first case described caused by EP.  相似文献   
996.
The effects of bakuchiol, a meroterpenoid isolated from the leaves of Psoralea glandulosa L., on phospholipase A2 (PLA2) activity from different sources, human neutrophil responses, zymosan air pouch and topical inflammation in mice, were investigated. This natural product was a weak inhibitor of secretory and intracellular PLA2 but dose-dependently reduced the formation of LTB4 and TXB2 by human neutrophils and platelet microsomes, respectively. In addition, bakuchiol inhibited degranulation in human neutrophils, whereas superoxide generation was not affected. In mice, bakuchiol decreased cell migration, myeloperoxidase activity and eicosanoid levels in the air pouch inflammation induced by zymosan. After topical administration, this compound was effective as an inhibitor of oedema and myeloperoxidase activity in the 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear oedema and significantly reduced the PGE2 content and ear oedema in the arachidonic acid-induced response. Bakuchiol is a natural anti-inflammatory agent able to control leukocytic functions such as eicosanoid production, migration and degranulation in the inflammatory site.  相似文献   
997.
OBJECTIVE: To determine if the luminal epithelium and/or exogenous transforming growth factor beta (TGFbeta) affects growth of the cricoid. DESIGN: Subglottises from 20 neonatal mice were subdivided into four groups: A, five subglottises with luminal epithelium grown in basic medium; B, five epithelium-free subglottises in basic medium; C, five epithelium-free subglottises in basic medium with supplemental TGFbeta1, and D, five epithelium-free subglottises in basic medium with supplemental TGFbeta3. RESULTS: Groups A and D demonstrated the greatest luminal area expansion. Group A rings demonstrated statistically higher chondrocyte proliferation than Groups B and C and lesser amounts of luminal apoptosis. Groups B and C rings demonstrated the least amount of cell proliferation, and greater luminal apoptosis relative to Group A. Groups A and D rings had similar apoptotic and proliferative results. CONCLUSIONS: Luminal epithelium exerts influence over the cricoid by increasing chondrocyte proliferation and decreasing the relative proportion of luminal chondrocytes that undergo apoptosis. Exogenous TGFbeta3, not TGFbeta1, also increases chondrocyte proliferation within the cricoid and appears to influence apoptosis as well.  相似文献   
998.
Abstract  – Avulsions are very common in a school setting. Teachers are often requested to help in such emergency situations. A survey consisting of seven simple questions regarding dental avulsion was answered by 60 teachers from five different elementary schools in Rio de Janeiro, Brazil, in order to evaluate their knowledge on the subject and establish a guideline to be followed when an accident of this type happens. A lack of technical information was observed among the teachers; most of them answered intuitively rather than on an informative basis. This study showed the need of a more effective communication between dental professionals and school teachers in order to better handle dental emergencies.  相似文献   
999.
Two samples of inpatients (493 and 158 subjects, respectively) of a large teaching hospital, collected using the same methodology and with a 20-year time frame, were analyzed aiming at finding information about alcohol consumption, abuse or dependence in the subjects' medical charts. Items reviewed were: the list of medical problems; hospital intake form; daily nursing review; medical anamnesis; pre-surgery records, and discharge forms. Only 54% and 50% of each sample, respectively, had some type of reference to alcohol consumption; when references were present, they were in most part incomplete, possibly reflecting distortions in the process of gathering information about alcohol consumption that involves the client and the health professionals. The authors discuss potential reasons for this, suggesting that lack of training of medical personnel in the identification of alcoholism, as well as prejudice towards its recovery, may be some of the underlying causes.  相似文献   
1000.
Serotonergic neurons in the fetal dorsal raphe nucleus were grafted together with fetal anterior hypothalamic tissue including the suprachiasmatic nucleus (SCN) to the anterior eye chamber of adult rats. After 6 weeks transplantation, the double grafts were immunocytochemically examined using antisera against serotonin, arginine vasopressin (AVP) and vasoactive intestinal polypeptide (VIP). The raphe grafts contained a large number of serotonin-immunoreactive neurons and fibers, but only a few AVP-immunoreactive fibers and VIP-immunoreactive neurons and fibers. On the other hand, numerous AVP- and VIP-immunoreactive neurons and fibers were found in the SCN of the anterior hypothalamic graft. Outgrowing serotonin-immunoreactive fibers from the raphe tissue were densely distributed in the anterior hypothalamic graft. In the SCN, however, only a few fibers were detected. The results demonstrate that the isolated anterior hypothalamic grafts can be innervated by the serotonergic neurons from the raphe grafts, but the innervation pattern of these fibers was quite different from the normal rat. The present results indicate that the isolated SCN has an inhibitory influence on the growth of serotonergic fibers.  相似文献   
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