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41.
OBJECTIVE: To perform a retrospective analysis of patients with nasopalatine duct cysts (NPDC) in Brazil and compare with previous analyses. MATERIALS AND METHODS: The files of the Laboratory of Oral Pathology (Minas Gerais Federal University) from 1966 to 1997 were reviewed. Demographic, clinical and histologic data of patients with nasopalatine duct cysts were collected. RESULTS: The mean age of patients with nasopalatine duct cysts at the time of diagnosis was 37.4 years and with a predilection for males. The majority of cases were asymptomatic. Histologically, non-keratinized stratified squamous epithelium alone or in combination with other epithelia was observed in 93% of the cases. Recurrence was not recorded. CONCLUSION: The demographic, histopathological, radiographic, and clinical data of the NPDC in our series are similar to previous studies in other populations. 相似文献
42.
43.
Cholecystokinin/opioid interactions 总被引:3,自引:0,他引:3
Cholecystokinin (CCK) acts as an anti-opioid peptide. The mechanisms of CCK-opioid interaction under normal and pathological conditions were examined with various techniques. Nerve injury induces upregulation of CCK mRNA and CCK2 receptors in sensory neurons. The involvement of CCK in spinal nociception in normal and axotomized rats was examined. The CCK2 receptor antagonist CI-988 did not reduce spinal hyperexcitability following repetitive C-fiber stimulation in normal or axotomized rats, suggesting that CCK is probably not released from injured primary afferents. With in vivo microdialysis intravenous (i.v.) or intrathecal (i.t.) morphine increased the extracellular level of CCK in the dorsal horn in a naloxone reversible manner. Morphine also released CCK after axotomy, but not during carrageenan-induced inflammation. In contrast, K(+)-stimulation failed to increase extracellular levels of CCK in axotomized rats, but did so in inflamed rats. Double-coloured immunofluorescence technique revealed partial co-localization between CCK-like immunoreactivity (LI) and mu-opioid receptor (MOR)-LI in superficial dorsal horn neurons. The presence of MOR in CCK containing neurons suggests a possible direct influence of opioids on CCK release in the spinal cord. Axotomy, but not inflammation, induced a moderate decrease in CCK- and MOR-LI in the dorsal horn. I.v. morphine further temporarily reduced CCK- and MOR-LIs in axotomized, but not in normal or inflamed, rats. While the effect of morphine on CCK-LI can be interpreted as the result of increased CCK release, the effect on MOR-LI may be related to changes in the microenvironment of the dorsal horn induced by nerve injury. 相似文献
44.
Snedaker SC Araújo RJ Capin AA Hearon MD Ofengand EA 《Toxicology and industrial health》1999,15(1-2):214-230
A search of the published and unpublished literature was conducted for analytical data on organochlorine compounds in tissues of subtropical and tropical marine organisms. The search was limited to reports of analyte concentrations in whole body or muscle tissue that were minimally determined by chromatographic procedures. A total of 1564 sample analyses consisting of 4431 analyte determinations were obtained for hard and soft corals, sponges, benthic seagrasses and algae, gastropods, fish and shellfish, and 'market-basket' (processed seafood) samples. For comparative purposes, data that were reported on a wet- or fresh-weight basis were uniformly converted to a common dry-weight estimate by dividing the wet-weight values by five (i.e., 80% water, 20% dry-weight tissue). Due to the large variation in analytical procedures, target analytes, chromatographic interpretations, and reporting units, the data were pooled by organochlorine-compound class (i.e., chlorinated cyclodienes, chlorinated aliphatics, chlorinated phenols, and chlorinated terpenes, hexachlorocyclohexanes, and polychlorinated biphenyls). A meta-analysis of the resulting database yielded a mean analyte concentration of 1594 +/- 8768 ng g-1 (dry weight), a median concentration of 23 ng g-1 (dry weight), and a mean of 2.89 analytes per sample; the corresponding mean tissue burden is 4608 ng g-1 (dry weight), the equivalent of 922 ng g-1 on a wet-weight basis. It was also found that the chlorinated aliphatics (i.e., DDT and its metabolites) constituted 40.15% of the reported analyte determinations. 相似文献
45.
Teicher B Holden S Ara G Sotomayor E Menon K Tarbell N Sallan S 《International journal of oncology》1992,1(6):625-630
The use of chemotherapy has led to improved treatment outcome for some pediatric patients with medulloblastoma. We have used a pre-radiation chemotherapy regimen consisting of vincristine and CDDP. The 9L gliosarcoma implanted intracranially and subcutaneously in the same animals was used as a preclinical model system to assess the efficacy of treatment combinations including: vincristine, CDDP, cyclo-phosphamide, etanidazole and radiation. The experimental endpoints were percent increase-in-lifespan, tumor growth delay and tumor cell survival. Both the tumor growth delay and percent increase-in-lifespan improved as the number of agents included in the chemotherapy regimen increased. so that the chemotherapy regimen including all four agents (ETA/VIN/CDDP/CTX) resulted in the greatest tumor growth delay (23.6 +/- 1.5 days) and the greatest increase-in-lifespan (35.8%). When radiation (20 Gray, single dose) was added to the treatment regimens the combinations of ETA/CTX/X-ray and ETA/VIN/CDDP/CTX/X-ray resulted in equivalent tumor growth delays (25.2 +/- 1.3 days and 25.8 +/- 1.7 days, respectively), while the greatest increase-in-lifespan (39.1%) was obtained with the five agent combination. The response of the 9L gliosarcoma to CDDP and cyclophosphamide over a dosage range was very similar to that of the murine FSaII fibrosarcoma. Our results indicate that etanidazole may be an effective chemosensitizer of combination chemotherapy and combined modality treatment regimens for brain tumors. 相似文献
46.
Francisco José H. N. Braga Elaine B. Araújo Edwaldo E. Camargo Leontina C. M. Tedesco-Marchesi Maria Cecilia M. Rivitti Hateme Bouladour Pierre Galle 《European journal of nuclear medicine and molecular imaging》1991,18(11):866-869
Gallium 67 imaging was used in 12 patients with documented Hansen's disease undergoing treatment or not, in an attempt to determine the pattern of the disease. Diagnosis was confirmed by histopathology in all patients. The Mitsuda reaction was seen in all patients. Specific nuclear studies were performed when needed to evaluate particular organs better. Gallium 67 images show homogeneous, diffuse and moderate accumulation over the entire skin surface (except for the face) of untreated patients with multibacillary disease. The facial skin in these cases presented homogeneous, diffuse but very marked uptake of gallium. Internal organ involvement was variable. There was a very good correlation among clinical, scintigraphic, immunological and histopathological data. The pattern of the body skin (skin outlining) and facial skin (beard distribution) may be distinct for untreated patients with multibacillary leprosy. 相似文献
47.
Beverly A. Teicher Julia S. Wong Hideya Takeuchi Laura M. Gravelin Gulshan Ara David Buxton 《Cancer chemotherapy and pharmacology》1998,42(1):24-30
Introduction: A series of molecules designed to be allosteric effectors of hemoglobin were examined for their potential as radiation sensitizers
in vitro and in vivo and for their potential as chemosensitizers in vivo as well as for their antimetastatic effect. Results: At a concentration of 100 μM for 1 h prior to, during and for 1.5 h after radiation exposure, the allosteric effectors decreased the shoulder of the radiation
survival curve of normally oxygenated EMT-6 cells and increased the slope of the radiation survival curves of hypoxic EMT-6
cells resulting in dose-modifying factors of 1.8 to 2.1. In vivo the allosteric effectors had antitumor activity against the
Lewis lung carcinoma and produced primarily additive tumor growth delay when administered along with fractionated radiation
therapy. When administered on days 4 through 18 after tumor implantation, the allosteric effectors, especially JP-7, RSR-13
and RSR-4, were highly effective antimetastatic agents in animals bearing Lewis lung carcinoma. In cell culture, simultaneous
exposure to the allosteric effectors (at 100 μM ) effectively sensitized EMT-6 cells to the effects of 4-hydroperoxycyclophosphamide, thiotepa and carboplatin. The allosteric
effectors were not very cytotoxic toward EMT-6 tumor cells from tumors treated in vivo with single doses of each molecule
nor were these agents very cytotoxic toward bone marrow CFU-GM taken from the same animals. Conclusions: It is likely that the allosteric effectors have a molecular target in addition to hemoglobin. Other possible targets include
hydroxymethyl-glutaryl-CoA reductase or microsomal cytochrome b5.
Received: 27 June 1997 / Accepted: 8 October 1997 相似文献
48.
Ines Lessa Maria Jenny Araújo Lucélia Magalh?es Naomar de Almeida Filho Estela Aquino Maria Cecília R Costa 《Pan American journal of public health》2004,16(2):131-137
OBJECTIVE: To estimate the frequency of modifiable cardiovascular risk factors, with and without inclusion of arterial hypertension, occurring simultaneously in a racially-mixed population. METHOD: A cross-sectional study was carried out with 1,298 adults aged > or = 20 years in the city of Salvador, Brazil, in 2000. Eight modifiable cardiovascular risk factors were assessed, in any combination: total cholesterol > or = 240 mg/dL; high density-lipoprotein cholesterol (HDL-c) < 40 mg/dL; triglycerides > or = 200 mg/dL; glycemia > or = 126 mg/dL + well-controlled diabetes; body mass index > or = 25 kg/m2, waist > or = 102 cm for males and > or = 88 cm for females, smoking and alcoholism. The results were stratified according to the number of simultaneous risk factors (zero to five or more and two or more risk factors). The data were analyzed in terms of estimated proportions and 95% confidence intervals (95%CI), with and without the inclusion of arterial hypertension (VI Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure [JNC-VI], United States of America), ratio of proportions and chi-square for proportions as a measure of association. RESULTS: Among men (41.4% of participants), 7.5% (95%CI: 2.5 to 9.7) did not present risk factors; 68.8% (95%CI: 65.0 to 72.8) presented two or more risk factors, not including hypertension. After inclusion of hypertension, 73.4% (95%CI: 69.7 to 77.1) presented two or more risk factors. Among women, 11.6% did not present risk factors. The presence of two or more risk factors, not including hypertension, was observed in 67.7% (95%CI: 64.8 to 71.4). After inclusion of hypertension, 71.7% (95%CI: 68.5 to 74.9) of the women presented two or more risk factors. Significant differences were observed for the presence of two or more risk factors in men with not more than 4 years of schooling vs. 5 to less than 11 years of schooling (P < 0.05); in women with not more than 4 years of schooling vs. 5 to less than 11 years of schooling; in women with not more than 4 years of schooling vs. 11 or more years of schooling (P < 0.01); and in black vs. white women (P < 0.01). CONCLUSIONS: The high proportion of clustering cardiovascular risk factors in Salvador, with or without hypertension, especially in the population with little schooling and in black individuals, suggests the need for broad social strategies to reduce social inequality, promote health, and facilitate the treatment of cardiovascular risk factors. 相似文献
49.
Veridiana M Rodrigues Silvana Marcussi Rafael S Cambraia Ana L de Araújo Natael R Malta-Neto Amélia Hamaguchi Eloísa A V Ferro Maria I Homsi-Brandeburgo José R Giglio Andreimar M Soares 《Toxicon》2004,44(3):305-314
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects. 相似文献
50.