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101.
The reductive metabolism in vivo of a flavoring additive, trans-4-phenyl-3-buten-2-one (PBO; trans-methyl styryl ketone) was investigated in rats and dogs. In both species, the double bond-reduced product, 4-phenyl-2-butanone (PBA), was detected by HPLC as the predominant species in blood after i.v. administration of PBO. PBA detected in rat blood was identified by comparison to the authentic sample. In contrast, the carbonyl-reduced product, trans-4-phenyl-3-buten-2-ol (PBOL) was also detected as a minor metabolite of PBO in both species. The area under the curve of PBOL in rat blood was only 3% of that of PBA. PBO was mutagenic in the Ames test using Salmonella typhimurium TA 100 when S-9 mix was added, but PBA and PBOL were not. It appears that PBO is mainly metabolized to PBA in vivo in rats and dogs as a detoxification pathway.  相似文献   
102.
Chromatographic and spectrometric discrimination of fentanyl and its 24 analogues are discussed. Twenty-three of 25 samples were discriminated from each other by gas chromatography (GC), and the combination of GC and mass spectrometry enabled discrimination of all 25 samples. Condensed-phase infrared spectrometry was also useful for the differentiation of structurally similar compounds, but vapor-phase infrared spectra were not useful for discrimination of fentanyls.  相似文献   
103.
Forty-seven strains of methicillin-resistantStaphylococcus aureus (MRSA) isolated from 47 patients with bacteremia were analyzed by chromosomal DNA digestion pattern using pulsed-field gel electrophoresis and evaluated for serological coagulase type, enterotoxin type, and toxic shock syndrome toxin-1 production. The mortality rate was significantly higher in the older patients (51 years of age) than in the younger patients (50 years of age) (50% vs. 4%, p=0.0007). Methicillin-resistantStaphylococcus aureus strains of serological coagulase type II were more likely to be associated with mortality in older patients than were strains of the other types (p=0.037).  相似文献   
104.
Relatively large amounts of DOPA as compared with the concentration of norepinephrine are found in human dental pulp. AADC and COMT are localized in blood vessel walls of human dental pulp. This localization suggests a functional relationship between COMT and AADC with regard to the metabolism of DOPA.  相似文献   
105.
Increased levels of urinary interleukin-6 in Kawasaki disease   总被引:4,自引:0,他引:4  
Kawasaki disease (KD) often presents with abnormal urinary findings, such as aseptic pyuria, mild proteinuria and microscopic haematuria. In this study, we measured urinary interleukin-6 (IL-6) by a sensitive sandwich ELISA assay using mouse monoclonal antibodies against recombinant IL-6 to elucidate the role of IL-6 in the pathogenesis of renal lesions in KD. Serum IL-6 levels were increased in acute KD as well as in febrile controls. Importantly, urinary IL-6 levels were consistently elevated in patients with acute KD, but much lower in febrile controls. Urinary IL-6 levels returned steadily to normal during the convalescent phase. In addition to IL-6, urinary levels ofN-acetyl--d-glucosaminidase (NAG) and 2-microglobulin (2-mg) were also elevated during the acute phase of this disease. Eosinophils and macrophages were identifiable in urinary sediments from these patients. The increased levels of urinary IL-6 in combination with increased NAG and 2-mg seemed to suggest the presence of certain renal parenchymal lesions with cellular infiltration during the acute phase of the disease. IL-6 may serve as clinically useful parameter for the detection and monitoring of the renal involvement in KD.  相似文献   
106.
Two cases of intracranial adenoid cystic carcinoma mimicking meningioma are reported. In one, MRI showed not only a homogeneously enhancing extra-axial tumour attached to the dura mater of the posterior cranial fossa, but also surrounding dural enhancement, the dural tail sign. In the second, CT demonstrated a well-demarcated enhancing extra-axial tumour, indistinguishable from a sphenoid ridge meningioma extending into the orbit. The neuroradiological features of intracranial adenoid cystic carcinoma may thus closely resemble those of meningioma.  相似文献   
107.
Forty patients underwent surgical resection for cancer of the middle and distal bile duct. Nineteen patients underwent a curative resection with 3- and 5-year survival rates of 63% and 48%, respectively. None of the patients who underwent a palliative resection survived two years. The factor most strongly associated with recurrence was the presence of tumor in the surgical margin. Recurrence was frequent in patients with disease in the middle portion of the bile duct who underwent extrahepatic biliary resection with choledochojejunostomy, while lower bile duct cancer was associated with peri-aortic or retroperitoneal recurrence. Pancreatoduodenectomy, with combined resection of the portal vein in middle bile duct cancer, regional lymphadenectomy, including peri-aortic lymph nodes and nerve plexus is required for curative resection of middle and distal biliary carcinoma beyond the early noninvasive stage.  相似文献   
108.
Clinical analysis of ossified thoracic ligaments and thoracic disc hernia]   总被引:2,自引:0,他引:2  
Thoracic lesions present several clinical problems, particularly in their diagnosis and treatment, compared with cervical or lumbar lesions. Since 1983, 18 cases of thoracic space lesions, excluding spinal tumors or trauma have been experienced: nine cases of ossification of yellow ligament (OYL), five of ossification of posterior longitudinal ligament (OPLL), and four of disc hernia (DH). In these 18 patients, problems of clinical manifestations, neuroradiological examination, and surgical approaches are analyzed and discussed. As clinical manifestations, there was a preponderant occurrence in males in the OYL group, while in the OPLL group all the patients were females. OYL and DH occurred at lower thoracic levels. Thirteen of the 18 patients showed combined lesions either in the cervical or in the lumbar regions, such as cervical OPLL, cervical spondylosis, lumbar DH, and lumbar canal stenosis. In the neuroradiological examinations diagnosis of the upper thoracic lesions was difficult. Computed tomography (CT) scan with intrathecal metrizamide injection seemed essential for examination of ossified thoracic lesions. However, because CT imaging of the entire spine is impractical, efficient use of this examination requires previous localization of the offending vertebral level from either the neurological findings or other neuroradiological examinations such as myelography. Magnetic resonance imaging seemed most useful for ruling out the thoracic compressing lesions. As for surgical approaches, posterior decompression was effective for OYL and the anterior approach was useful for OPLL and DH. In patients with "tandem lesions," neurological and neuroradiological findings played an important role in deciding the responsible site.  相似文献   
109.
Summary Twenty-seven patients with juvenile nonprogressive muscular atrophy localized in the hand and forearm were analyzed. The clinical characteristics were juvenile male occurrence, insidious onset, specific distribution of localized muscular atrophy and a stationary course. On electromyography, denervation voltage (or giant NMU) is found in the atrophied muscles and sometimes in contralateral nonatrophied ones. Sensory disturbance was not remarkable. Although the etiological factor was not known, strenuous exercise of arms in sports was noted frequently in the history.
Zusammenfassung 27 Patienten mit juveniler nonprogressiver Muskelatrophie, lokalisiert an der Hand und dem Vorderarm wurden analysiert. Klinisch charakteristische Merkmale waren Vorkommen bei jungen Männern, schleichender Beginn, lokalisierter Befall der erwähnten Muskelgruppe und stationärer Verlauf nach einer anfänglichen Progression. Elektromyographisch wurde eine Denervation in den atrophischen Muskeln und manchmal in den Muskeln der kontralateralen Seite bemerkt. Sensible Ausfälle waren nicht eindrücklich. Obgleich die Ätiologie nicht klar war, wurde häufiger Gebrauch der Hand im Sport in der Krankheitsgeschichte bemerkt.
  相似文献   
110.
Three rare cases of purely intraventricular aneurysms are described, including a unique aneurysm in the fourth ventricle. A 30-year-old female, a 47-year-old male, and an 11-year-old girl presented with disturbance of consciousness due to massive intraventricular hemorrhage. Digital subtraction angiography revealed an idiopathic peripheral aneurysm in the fourth ventricle in the first patient, and aneurysms in the lateral ventricle associated with moyamoya disease in the latter two patients. The former two aneurysms were treated surgically and histologically confirmed to be pseudoaneurysms. The latter aneurysm disappeared spontaneously within 2 months after onset. The aneurysm in the lateral ventricle was resected via a parietal corticotomy with stereotactic insertion of an 8-Fr silicone tube to guide the approach route. This method was very useful because computerized neuronavigation was not available. The aneurysm in the fourth ventricle was resected via a midline suboccipital approach with C-1 laminectomy. Conservative treatment is usually recommended initially for patients with intraventricular aneurysm because spontaneous cure often occurs. We recommend direct surgery if the size of the aneurysm remains unchanged, because the risk of surgery has decreased recently owing to new techniques for neuronavigation.  相似文献   
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