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61.
A 64-year-old man in a severely immunocompromised state due to acute myelogenous leukemia died, respirator-unaided, about 10 h after the abrupt onset of coma. An earlier blood culture had yielded Bacillus cereus. The autopsy, performed 2 h after death, demonstrated diffuse subarachnoid hemorrhage without berry aneurysms, and the formalin-fixed brain was tinged with gray-brownish discoloration. The sections of the brain presented a whitish tint of the surface layer of all portion of the cerebral cortices, even those in the sulci. Histological examination of the brain revealed leptomeningeal B. cereus dissemination, and widespread necrosis of the leptomeninges and arachnoid vessels without inflammatory cell reaction. The grossly recognizable whitish surface layer of the cerebral cortex showed overt hyperchromatism, and contained neurons more degenerative than those located in the deeper cortical layer. The total absence of inflammatory reaction may be explained by a combination of the immunocompromised state of the patient and the character of B. cereus infection, which in itself induces little inflammatory reaction. The prominent lesions were confined to the cerebral surface layer and leptomeningeal tissue including the arachnoid vessels, which were all bathed in the cerebrospinal fluid, suggesting that some necrotizing toxins had been secreted into the fluid by the B. cereus. The necrosis of arachnoid vessels is thought to have in turn caused diffuse subarachnoid hemorrhage and marked disturbance of the cerebral blood flow, resulting in the terminal coma. Received: 4 April 1996 / Revised, accepted: 8 September 1996  相似文献   
62.
We previously reported that healthy adult males who consumed coix seeds for 1 week demonstrated an increased intestinal abundance of Faecalibacterium prausnitzii and altered peripheral lymphocyte subset percentages. However, the mechanism underlining these effects has not been elucidated. Therefore, cytokines and metabolites in plasma obtained in this study are comprehensively analyzed. A total of 56 cytokines and 52 metabolites in the plasma are quantified. Among them, 14 cytokines and 9 metabolites show significant changes in their levels following coix seed consumption. We examine the relationship between these changes and those in peripheral lymphocyte subset percentages and intestinal abundance of F. prausnitzii, which is also considerably altered following coix seed consumption. The galectin-9 concentration considerably decreased after coix seed consumption, and these changes correlate with those in cytotoxic T cells and pan T cells. Therefore, galectin-9 is possibly involved in the changes in peripheral lymphocyte subset percentages induced by coix seed consumption.  相似文献   
63.
64.
Left ventricular function during exercise and recovery was investigated in patients with angina pectoris, ST segment depression during exercise and angiographically normal coronary arteries (syndrome X) using a continuous left ventricular function monitor with cadmium telluride detector (CdTe-VEST). Fourteen patients with syndrome X and 14 patients with atypical chest pain without ST segment depression during exercise and normal coronary arteries (control group) performed supine ergometric exercise after administration of 740–925 MBq of technetium-99m labelled red blood cells, and left ventricular function was monitored every 20 s using CdTe-VEST. Left ventricular ejection fraction (EF) response was impaired (55% increase from rest to peak exercise) in 11 or 14 patients with syndrome X but in none of the control patients. Resting EF was similar in the two groups (62.1%±6.7% in patients with syndrome X, 61.9%±6.2% in controls); however, EF increase from rest to peak exercise was lower in syndrome X (–3.1±9.5% vs 14.7%±7.4%, P <0.001). After cessation of exercise, all patients showed rapid EF increase over baseline and this EF overshoot was lower (19.3%±8.3% vs 26.4%±7.3%, P <0.001) with the time to EF overshoot longer (114±43 s vs 74±43 s, P<0.05) in patients with syndrome X. Thus, in patients with syndrome X, left ventricular dysfunction was frequently observed during exercise in spite of normal epicardial coronary arteries. Correspondence to: J. Taki  相似文献   
65.
Summary The gene encoding the specific glycosyltransferases which catalyze the conversion of the H antigen to A or B antigens shows a slight but distinct variation in its allelic nucleotide sequence and can be divided into 6 genotypes when digested with specific restriction enzymes. We extracted DNA from formalin-fixed, paraffin-embedded tissues using SDS/proteinase K treatment followed by phenol/chloroform extraction. The sequence of nucleotides for the A, B and O genes was amplified by the polymerase chain reaction (PCR). DNA fragments of 128 by and 200 by could be amplified in the second round of PCR, using an aliquot of the first round PCR product as template. Degraded DNA from paraffin blocks stored for up to 10.7 years could be successfully typed. The ABO genotype was deduced from the digestion patterns with an appropriate combination of restriction enzymes and was compatible with the phenotype obtained from the blood sample.  相似文献   
66.
Background: In cardiac myocytes, lidocaine reduces but mexiletine increases adenosine triphosphate (ATP)-sensitive K+ currents, suggesting that these class Ib antiarrhythmic drugs may differentially modify the activity of ATP-sensitive K+ channels. The effects of lidocaine and mexiletine on arterial relaxations induced by K+ channel openers have not been studied. Therefore, the current study was designed to evaluate whether lidocaine and mexiletine may produce changes in relaxations to the ATP-sensitive K+ channel openers cromakalim and pinacidil in isolated rat thoracic aortas.

Methods: Rings of rat thoracic aortas without endothelia were suspended for isometric force recording. Concentration-response curves were obtained in a cumulative fashion. During submaximal contractions to phenylephrine (3 x 10 (-7) M), relaxations to cromakalim (10-7 to 3 x 10-5 M), pinacidil (10-7 to 3 x 10-5 M), or diltiazem (10-7 to 3 x 10 (-4) M) were obtained. Lidocaine (10-5 to 3 x 10-4 M), mexiletine (10-5 to 10-4 M) or glibenclamide (5 x 10-6 M) was applied 15 min before addition of phenylephrine.

Results: During contractions to phenylephrine, cromakalim and pinacidil induced concentration-dependent relaxations. A selective ATP-sensitive K+ channel antagonist, glibenclamide (5 x 10-6 M), abolished these relaxations, whereas it did not alter relaxations to a voltage-dependent Ca (2+) channel inhibitor, diltiazem (10-7 to 3 x 10-4 M). Lidocaine (more than 10-5 M) significantly reduced relaxations to cromakalim or pinacidil in a concentration-dependent fashion, whereas lidocaine (3 x 10-4 M) did not affect relaxations to diltiazem. In contrast, mexiletine (more than 10-5 M) significantly augmented relaxations to cromakalim or pinacidil. Glibenclamide (5 x 10-6 M) abolished relaxations to cromakalim or pinacidil in arteries treated with mexiletine (10-4 M).  相似文献   

67.
We present a case of malignant fibrous histiocytoma of the spermatic cord. An 86-year-old man was admitted to the hospital with a right painless scrotal mass. Under the diagnosis of a testicular tumor, right radical orchiectomy was performed. Grossly, the tumor firmly adhered to the spermatic cord. The right testis and epididymis were normal. The histologic diagnosis was malignant fibrous histiocytoma. There was local recurrence 2 months after surgery. The recurrent tumor was resected with the surrounding soft tissue, but the patient died 5 months after the initial operation.  相似文献   
68.
Aortobronchial fistula is a fatal complication after thoracic aortic surgery. So far, treatment options for aortobronchial fistula have included surgical and endovascular stent-graft methods. Herein, a case of an aortobronchial fistula with life-threatening hemoptysis managed with transcatheter embolization of the fistula with N-butyl cyanoacrylate is reported. For the patient with an aortobronchial fistula who cannot be treated by surgical or endovascular stent-graft methods, transcatheter embolization of the fistula may be the only available life-saving method.  相似文献   
69.
PURPOSE: We studied preoperative variables in a contemporary series of men who underwent nonnerve sparing radical prostatectomy in an effort to establish criteria that would predict side specific extraprostatic extension (EPE) of cancer. MATERIALS AND METHODS: We reviewed the records of 430 patients who underwent radical prostatectomy for localized prostate cancer with no prior therapy between 1996 and 1998, and for whom we had at least sextant biopsy information. We evaluated biopsy data (Gleason score, maximum length of cancer in positive cores, percent of cancer per involved core, proportion of positive biopsy cores, tumor location and number of positive biopsy cores) and correlated these findings with EPE at the neurovascular bundle and posterior lateral (NVB/PL) region. RESULTS: We found that a higher number of positive cores, a higher biopsy Gleason score on a side, a positive core at the basal region, 50% or greater tumor in the core or a maximum tumor length of 7 mm or greater increased the likelihood that EPE was present at the NVB/PL region on the corresponding side of the prostate. On multivariate analysis maximum tumor length 7 mm or greater and positive basal core location were the strongest independent predictors of EPE at the NVB/PL region on a given side (p <0.0001 and 0.002, respectively). CONCLUSIONS: Excluding any patient with 1 positive biopsy core with a maximum tumor length of 7 mm or greater plus a positive basal core of any tumor length and grade can decrease the risk of EPE at the NVB/PL region to approximately 10%.  相似文献   
70.
BACKGROUND: Concerning the relationship between morphology and clinical outcome, there have been many reports using computed tomography/myelography but not so many using axial magnetic resonance imaging (MRI) of the spinal cord. This is the first report to correlate axial cord image, intensity changes in MRI, and cord expansion pattern using intraoperative ultrasonography. OBJECTIVE: The objectives were to correlate MRI studies, axial cord images/expansion, and changes in MRI intensity to see if there is a direct prognostic significance to these changes and to determine whether preoperative axial MRI images of the spinal cord predict recovery from compressive myelopathy. METHODS: Posterior cervical decompressions with laminoplasty were performed in 44 patients with cervical myelopathy due to ossification of the posterior longitudinal ligament. On T2-weighted MR images, the cross-sectional shape of the cord at the level of maximal compression was categorized as boomerang, teardrop, or triangle. Additionally, with use of intraoperative ultrasonography, the expansion pattern of the cord that occurred intraoperatively was contrasted with that seen on postoperative MR images. RESULTS: Clinical recovery rates were the worst for those with triangular, intermediate for those with boomerang, and the best for those with teardrop shape. Preoperative low T1 and high T2 signals were found in most cases with triangular cord configurations. Triangular cord configurations showed the least expansion among the three categorized spinal cords. CONCLUSION: Patients with triangular deformity of the cord have atrophy as confirmed on MR studies where there is a low T1 and high T2 signal in the cord. Poor postoperative clinical recovery correlates with the lack of postoperative cord expansion on either MR or ultrasound evaluations. Those with either teardrop or boomerang deformities demonstrate a relatively good recovery rate.  相似文献   
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