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101.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented. 相似文献
102.
Vinicio Granados-Soto Marcelo de O. Rufino Lúcia D. Gomes Lopes Srgio H. Ferreira 《European journal of pharmacology》1997,340(2-3)
The effect of inhibition of nitric oxide synthesis and guanylate cyclase on the peripheral antinociceptive effect of morphine was assessed by using the formalin test in the rat. Saline, NG-monomethyl-
-arginine, a nitric oxide synthesis inhibitor (50 μg) and methylene blue, a guanylate cyclase inhibitor (500 μg), did not exhibit any antinociceptive activity. However, morphine (10 μg) produced a significant antinociceptive effect in phases 2a and 2b, which was reduced by pretreatment with either NG-monomethyl-
-arginine or methylene blue. These results suggest that the local administration of morphine induces antinociception by the activation of the
-arginine–nitric oxide–cGMP pathway. 相似文献
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103.
104.
Nucci M Pulcheri W Spector N Bueno A Silveira S Marangoni D Ferreira R Deoliveira H 《Oncology reports》1994,1(6):1101-1105
To assess the efficacy of quinolones in the prophylaxis of infections in neutropenic patients with acute non-lymphocytic leukemia, and to evaluate the emergence of quinolone resistance in two University Hospitals in Brazil, we retrospectively compared 101 consecutive episodes of neutropenia managed with quinolone prophylaxis between 1989 and November 1993, and 26 previous episodes without prophylaxis, and reviewed the results of in vitro sensitivity of Gram-negative strains to quinolones in the same period. Prophylaxis with quinolones resulted in less episodes of bacteremias (21% vs. 69%, p=10(-7)), including Gram-negative bacteremias (6% vs. 38%, p=10(-5)), with no statistically significant difference in the death rate (18% vs. 31%, p=0.14, 95% confidence interval -6-32). The resistance of Gramnegative strains to quinolones rose from 7% to 18% between 1990 and 1993 (p=10(-5)). The resistance against ceftazidime and amikacin, the agents used in the empirical antibiotic therapy, increased in the same proportion as the quinolones. Given the limited benefit of quinolones as prophylaxis and the increasing number of quinolone-resistant Gram-negative strains observed in our hospitals, the use of quinolones as prophylaxis must be seriously questioned. A stricter control of the use of quinolones in these hospitals might decrease resistance. 相似文献
105.
V M Bessa Ferreira M C Portela 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1999,15(2):317-324
Data from the Hospital Information System (SIH-SUS) were linked to data from the AIDS Case Reporting System (Sinan) to assess the level of under-reporting of AIDS cases in the city of Rio de Janeiro. A high level of unreported cases(42.7%) was observed for patients treated in hospitals under Brazil's Unified Health System in the city of Rio. Bivariate analysis showed an association between reporting to the Sinan and age, principal diagnosis, and type of hospital. 相似文献
106.
O'Neill P Trombley L Gundel M Hunter T Nicklas JA Ferreira ML Bugallo MJ Farias AC Lohr A Diamantopoulos M Raskin S 《Arquivos de neuro-psiquiatria》1999,57(4):907-911
The mutation in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene has been determined in two brothers affected with Lesch-Nyhan syndrome. Female members of the family who are at risk for being heterozygous carriers of the HPRT mutation were also studied to determine whether they carry the mutation. DNA sequencing revealed that the boys' mother is heterozygous for the mutation in her somatic cells, but that three maternal aunts are not heterozygous. Such carrier information is important for the future pregnancy plans of at-risk females. The mutation, an A-->T transversion at cDNA base 590 (590A-->T), results in an amino acid change of glutamic acid to valine at codon 197, and has not been reported previously in a Lesch-Nyhan syndrome male. This mutation is designated HPRTBrasil. 相似文献
107.
Ferreira EL Alexsandro da Silva E Pereiro B Roque Devesa A Zungri Telo E 《Actas urologicas espa?olas》1999,23(10):895-897
While prevalence of uterine leiomyoma is high, its presentation affecting the urinary tract is uncommon. We contribute the cases of two adult women with symptoms of nephritic colic and urinary retention. Etiology was acute obstruction of the urinary tract due to previously asymptomatic urine myomas. Management in both patients was surgery, using hysterectomy to resolve the urinary obstruction. A brief review of the literature is included. 相似文献
108.
The minimum sum of absolute errors regression: a robust alternative to the least squares regression.
S C Narula P H Saldiva C D Andre S N Elian A F Ferreira V Capelozzi 《Statistics in medicine》1999,18(11):1401-1417
This paper concerns the minimum sum of absolute errors regression. It is a more robust alternative to the popular least squares regression whenever there are outliers in the values of the response variable, or the errors follow a long tailed distribution, or the loss function is proportional to the absolute errors rather than their squared values. We use data from a study of interstitial lung disease to illustrate the method, interpret the findings, and contrast with least squares regression. We point out some of the problems with the least squares analysis and show how to avoid these with the minimum sum of absolute errors analysis. 相似文献
109.
B B Lorenzetti G E Souza S J Sarti D Santos Filho S H Ferreira 《Journal of ethnopharmacology》1991,34(1):43-48
Oral administration of an infusion of lemongrass (Cymbopogon citratus) fresh leaves to rats produced a dose-dependent analgesia for the hyperalgesia induced by subplantar injections of either carrageenin or prostaglandin E2, but did not affect that induced by dibutyryl cyclic AMP. These results indicate a peripheral site of action which was confirmed with the essential oil obtained by steam distillation of the leaves. Silica gel column fractionation of the essential oil allowed the identification of myrcene as the major analgesic component in the oil. Identification of the components was made by thin-layer chromatography and checked by mass spectrometry. The peripheral analgesic effect of myrcene was confirmed by testing a standard commercial preparation on the hyperalgesia induced by prostaglandin in the rat paw test and upon the contortions induced by intraperitoneal injections of iloprost in mice. In contrast to the central analgesic effect of morphine, myrcene did not cause tolerance on repeated injection in rats. This analgesic activity supports the use of lemongrass tea as a "sedative" in folk medicine. Terpenes such as myrcene may constitute a lead for the development of new peripheral analgesics with a profile of action different from that of the aspirin-like drugs. 相似文献
110.
M elikta N Okur KS Aikimbaev F Binokay M Sert E Akgül 《Journal of Medical Imaging and Radiation Oncology》2004,48(3):398-400
Pheochromocytomas of the bladder are rare neoplasms, constituting <0.06% of all vesical tumours. Common presenting features of this tumour include episodes of sweating, hypertension, haematuria and postmicturition syncope. We describe a case of bladder pheochromocytoma in a 66‐year‐old man whose only symptom of macroscopic haematuria was initially assessed with ultrasonography. Clinical presentation highlights the need for a high index of suspicion during sonographic evaluation of bladder neoplasms because such tumours might present without symptoms of adrenergic excess. 相似文献