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991.
992.
S Rault JC Lancelot L Bouyazza M Robba MA Quermonne B Nammathao J Louchahi-Raoul R Marcy 《European journal of medicinal chemistry》1991,26(9)
La synthèse de nouveaux pyrrolo[1,2-a]indoles est décrite. Le test d'habituation révèle in vivo pour certains dérivés une activité psychostimulante non amphétaminique. 相似文献
993.
Erythroid-specific processing of human beta spectrin I pre-mRNA 总被引:3,自引:2,他引:1
994.
Camdessanche JP Antoine JC Honnorat J Vial C Petiot P Convers P Michel D. 《Journal of the peripheral nervous system : JPNS》2002,7(3):207-207
Peripheral neuropathy is a rare, yet treatable manifestation of sarcoidosis, a multisystem disorder characterized by the presence of non‐caseating granulomas that are seldom found in nerve biopsy specimens. In order to learn more about the subject, we reviewed our clinical and pathological findings in a series of 11 patients (six men and five women aged 26‐83 years) with symptomatic neuropathy associated with characteristic granulomas in nerve biopsy specimens. Only two patients were known to have sarcoidosis before the occurrence of the neuropathy. The neuropathy was focal or multifocal in six patients, including one with a multifocal neuropathy associated with conduction blocks, and one with a multifocal axonal motor deficit. Four patients had a distal symmetrical deficit and one patient had a Guillain‐Barré‐like syndrome with facial diplegia and respiratory failure. Serum angiotensin‐converting enzyme concentration was elevated in only two patients. Epineurial granulomas and perineuritis were present in all nerve specimens. The inflammatory infiltrates invaded the endoneurium, following connective tissue septae and blood vessels, in five patients. Multinucleated giant cells were found in eight patients and necrotizing vasculitis in seven. Inflammatory lesions were associated with variable, asymmetrical involvement of nerve fascicles and axon loss. A muscle specimen was sampled during the same procedure in 10 patients. It showed inflammatory infiltrates and granulomas in nine patients and necrotizing vasculitis in two. Immunolabeling showed a mixed inflammatory infiltrate of T cells (predominantly CD4+ cells) and macrophages, in keeping with a delayed hypersensitivity reaction. In addition to nerve involvement, all patients had at least one other tissue or organ affected, including muscle in nine patients, lungs and/or intrathoracic lymph nodes in eight, skin in three, arthritis in two, and peripheral lymph nodes, stomach and eye in one patient each. Most patients improved on corticosteroids. Two patients remain free of symptoms after 7 years. Severe side‐effects of long‐term treatment with corticosteroids occurred in two patients, leading to death in one. This study illustrates the wide range of clinical manifestations of sarcoid neuropathy and the frequent association of granulomatous inflammatory infiltrates with necrotizing vasculitis and with silent or symptomatic involvement of other organs. 相似文献
995.
Leptomeningeal metastasis: MR imaging 总被引:3,自引:0,他引:3
Seven patients with central nervous system neoplasia and leptomeningeal metastases, proved either at initial diagnosis or on follow-up with contrast material-enhanced computed tomography (CT), were evaluated with magnetic resonance (MR) imaging. In two patients, diffuse sulcal enhancement on CT scans was inapparent on T1- or T2-weighted MR images. Likewise, in four patients diffuse cisternal enhancement on CT scans was not identifiable with MR. Nodular or focal cisternal masses were identified with both CT and MR imaging in three patients; in two, however, MR imaging provided less information. Ependymal and subependymal metastases identified with CT (two patients) were indistinguishable on MR images from periventricular abnormalities of radiation therapy and/or hydrocephalus. These findings suggest that leptomeningeal metastasis may be so subtle or inapparent as to be overlooked with MR imaging alone. Thus, CT and MR imaging should be considered complementary techniques for initial diagnosis and follow-up of tumors with a propensity for leptomeningeal metastasis. 相似文献
996.
Fetal lung maturation involves a number of separate developmental processes. An ultrasonic technique is reported for grading the dynamic behavior of the right middle lobe or lingula in the second or third trimesters on ultrasound (US) study. Fetal lungs are stiff initially. Lung compressibility during diastole is typical after 36 weeks' gestational age, when phospholipid profiles of the amniotic fluid also indicate lung-tissue maturity. Compressibility also occurs earlier in the third trimester and has indicated, in preliminary observations on a small subgroup of infants delivered prematurely, a low risk of subsequent neonatal respiratory distress syndrome. High-speed magnification US study of fetal lung compressibility can be used to evaluate fetal lung development, possibly independently of gestational age and of conventionally measured lecithin/sphingomyelin values in amniotic fluid. 相似文献
997.
The role of glutathione reductase in maintaining human granulocyte function and sensitivity to exogenous H2O2 总被引:1,自引:0,他引:1
Human granulocytes (polymorphonuclear leukocytes, PMN) produce H2O2 and other reactive oxygen species while undergoing phagocytosis. To examine the role of the glutathione cycle in metabolizing H2O2, we incubated PMN with 1,3-bis (2-chloroethyl) nitrosourea (BCNU). Incubation of PMN with BCNU results in a dose-dependent inhibition of PMN glutathione reductase (GRED), with 50% inhibition occurring at approximately 2 micrograms/mL BCNU. PMN hexose monophosphate shunt activity stimulated with an exogenous H2O2-generating system was inhibited only when the GRED activity was reduced to less than 30% of control. BCNU-treated cells contained lower levels of reduced sulfhydryls and reduced glutathione, which decreased even more in the presence of an exogenous H2O2-generating system. The effect of BCNU and exogenous H2O2 on various aspects of phagocytosis were examined. Exposure of BCNU-treated PMN to an H2O2-generating system resulted in an inhibition of chemotactic peptide-induced shape changes and degranulation. The ability of BCNU-treated cells to produce O2- was diminished only when the PMN were incubated with an H2O2-generating system in the presence of cyanide. Ingestion of opsonized bacteria by BCNU-treated PMN was unaffected by incubation in an H2O2-generating system even in the presence of cyanide. We conclude that PMN GRED is inhibited by BCNU, the ability of PMN to metabolize H2O2 is affected only when GRED is reduced more than 70%, this inhibition affects the glutathione content of these cells, and some, but not all of the phagocytic functions of GRED-inhibited PMN are inhibited after exposure to an H2O2-generating system. 相似文献
998.
999.
1000.
In a prospective study, the effect of infusion of a low-density contrast material was evaluated as an adjunct to high-density, double-contrast imaging of the sigmoid colon. After double-contrast barium enema (DCBE) study, 52 consecutive patients with sigmoid diverticulosis received an additional 500-750-mL enema either with water or a 1.5% barium suspension for computed tomography. Rectosigmoid radiographs were evaluated for luminal distention, visualization of the interhaustral space, definition of diverticula, and interpretation of polypoid defects. While double-contrast views were excellent in 21% of patients, improvement in multiple factors by water or 1.5% barium flush resulted in improved sigmoid images in 65% and 75% of patients, respectively. Polyps were confirmed and artifactual defects confidently excluded. Sigmoid flush, particularly with low-density barium, is a simple adjunct to DCBE study that improves visualization of the diverticular sigmoid and increases interpretive confidence. 相似文献