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81.
Grossman RI; Braffman BH; Brorson JR; Goldberg HI; Silberberg DH; Gonzalez- Scarano F 《Radiology》1988,169(1):117-122
Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies. 相似文献
82.
83.
Fibrodysplasia ossificans progressiva: report of two cases 总被引:3,自引:0,他引:3
Fonseca JE Branco JC Reis J Evangelista T Tavares V Gomes AR Queiroz MV 《Clinical and experimental rheumatology》2000,18(6):749-752
Fibrodysplasia Ossificans Progressiva (FOP) is a rare hereditary connective tissue disease, genetically inherited as an autosomal dominant trait with complete penetrance but variable expressivity. Onset is typically in childhood and progressive involvement of the spine and proximal extremities leads to immobility and articular dysfunction. We present two cases with the typical features of FOP and a review of the pathogenesis, clinical manifestations and treatment options of this rare disease. 相似文献
84.
Daniela Medeiros Milhomem Cardoso Paulo Moacir de Oliveira Campoli Chizu Yokoi Flávio Hayato Ejima Paulo Adriano de Queiroz Barreto Alexandre Menezes de Brito Eliane Duarte Mota Ailton Cabral de Fraga Junior Orlando Milhomem da Mota 《Gastric cancer》2008,11(4):226-232
Background Endoscopic resection is an adequate treatment for subgroups of patients with early gastric cancer. Endoscopic submucosal dissection
(ESD) represents a recent advance and leads to good results when adequately indicated. There is great experience with this
technique in Japan and it is gaining acceptance among Western endoscopists. We present the first gastric ESD series performed
in Brazil.
Methods Patients with well-differentiated adenocarcinomas macroscopically classified as early cancer, less than 30 mm with no ulcer
or scar, were included. ESD was performed with an insulated-tip knife and electrosurgical unit with endocut mode. Clinicopathological
aspects and morbidity were evaluated. The study was approved by the local ethics committee and informed consent was obtained
from all participant subjects.
Results From October 2005 to July 2007, 160 patients received surgical treatment for gastric cancer; 44 patients (27.5%) had early
gastric cancer. In this latter group, 15 procedures (ESD) were performed in 12 patients. The mean size of the lesions was
16.8 mm. Almost half of the lesions were located in the proximal third of the stomach and the mean elapsed time for the procedure
was 140 min. In 80% of the cases resection was en bloc and 80% of the resections were considered curative. We had three perforations,
which were managed clinically, and no bleeding.
Conclusion When adequately indicated, ESD is a safe and feasible technique. 相似文献
85.
Queiroz MS 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2000,16(2):363-375
This article focuses on social representations of alternative medicines by a group of professors from the School of Medicine and health professionals from the public health system in the city of Campinas, S?o Paulo, basically physicians and nurses. The article also emphasizes personal trajectories by which these health professionals opted for a dissident theoretical and practical perspective vis-à-vis the hegemonic positivist scientific medical paradigm. The research methods were mainly ethnographic, from a phenomenological perspective. The article concludes by sustaining (in theoretical terms) the importance of these dissident perspectives for scientific development. 相似文献
86.
Phytochemical investigation of the CH2Cl2 extract of Erythrina vogelii led to the isolation of five isoflavonoids. Three prenylated isoflavonoids are new natural compounds. The isolation of the antifungal compounds was monitored by inhibition of the growth of Cladosporium cucumerinum in a direct TLC bioautographic assay. The structures of these compounds were elucidated by spectroscopic techniques. 相似文献
87.
This study investigated the relationship between the use of illicit drugs and sexual-risk-behavior in a sample of students aged 14 to 21 years at a public high school in S?o Paulo in 1997. A total of 689 useable questionnaires documented the sample in consumption of psychoactive substances and sexual behavior. Sexual behavior of drug users and non-users was compared regarding history of complete sexual intercourse, age at first sexual intercourse, use of condoms, sexual intercourse with sex workers, and prostitution. Drug users (N = 366) presented a higher frequency of complete sexual intercourse (80.8% of users versus 53.5% of non-users), (N = 323, p < .001), a younger age at first sexual intercourse (on average 15.2 years in users versus 15.7 among non-users, p < .005), a trend toward lower use of condoms (56.7% among users versus 65.3% among non-users, p < .1), and more sexual intercourse with sex workers (31.1% among users versus 15% among non-users, p < .001). Sexual-risk-behavior increased with the number of drugs used. Alcohol and marijuana use were associated with the highest sexual-risk-behavior. These data are essential for the development of more specific preventive strategies, focusing on male alcohol and marijuana users. 相似文献
88.
Kobayashi E D'Agostino MD Lopes-Cendes I Andermann E Dubeau F Guerreiro CA Schenka AA Queiroz LS Olivier A Cendes F Andermann F 《Epilepsia》2003,44(8):1080-1084
PURPOSE: To describe postoperative outcome in patients with familial mesial temporal lobe epilepsy (FMTLE). METHODS: We studied FMTLE patients who underwent surgical treatment for refractory seizures. FMTLE was defined when at least two individuals in a family had a clinical EEG diagnosis of MTLE. Preoperative investigation included magnetic resonance imaging (MRI), interictal/ictal EEGs, and neuropsychological evaluation. We used Engel's classification for postoperative outcome. RESULTS: To date, 20 FMTLE patients have been operated on, with 1.6 to 9.8 years of follow-up (mean, 5.5 years). Hippocampal atrophy (HA) and other signs of mesial temporal sclerosis (MTS) were present in 18 patients (15 unilateral). Seizures were recorded in 19 patients. Seventeen (85%) patients are in class I. Two patients had normal hippocampal volumes (HcV): one (5%) is in class II and the other (5%) in class IV (extratemporal seizures developed after surgery). One (5%) patient had bilateral HA and is in class III. Qualitative histopathology showed MTS with different degrees of severity. CONCLUSIONS: Refractory FMTLE patients have good surgical outcome when unilateral or clearly asymmetric HA is identified. Preoperative investigation should be the same as that in patients with sporadic refractory MTLE. 相似文献
89.
Since the use of bovine instead of human dentine to evaluate cariogenic and anticariogenic substances is not well established, this in situ study was conducted. Eleven volunteers wore palatal acrylic devices containing 4 dentine slabs (2 human and 2 bovine). Sucrose solution (20%) was dripped over all slabs 4 times a day, simulating a cariogenic challenge. Dentifrice slurries, fluoridated or not, were dripped over specified dentine slabs 3 times a day to evaluate caries reduction. After 14 days, the biofilm formed on the dentine slabs was collected for microbiological analysis. In dentine, mineral loss (DeltaZ) and lesion depth (LD) were determined by cross-sectional microhardness and by polarized light microscopy, respectively. The total streptococci and mutans streptococci counts in the biofilm formed either on human or on bovine slabs, whether treated or not with fluoride dentifrice, were not statistically different. The DeltaZ and the LD values of dentine treated with fluoride dentifrice were significantly lower than the values of dentine treated with non-fluoride dentifrice. The differences in the DeltaZ and LD values between the human and bovine dentine were not statistically significant. The results suggest that bovine dentine can be used instead of human to evaluate caries development and inhibition. 相似文献
90.
Rodrigues CH Mori M Rodrigues AA Nascimento EJ Gonçalves FM Santana KC 《The Journal of clinical pediatric dentistry》2003,27(4):339-346
Since there is a lack of standardization of occlusal contacts for deciduous dentition, this study assessed distribution and different types of occlusal contacts at maximal intercuspal position in children from 4 to 5 1/2 years, with normal occlusion, finding a pattern able to be used as a reference for dentists during the rehabilitation of these children, and suitable for development of the craniofacial complex. 相似文献