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71.
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   
72.
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   
73.
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   

74.
Functional competition has been shown to lead to a detrimental outcome in auxiliary liver transplantation. We evaluated the interaction in auxiliary partial orthotopic liver transplantation between the native liver and the graft in terms of portal flow and regeneration. The need for diversion of the portal flow to the graft was also assessed. Reduced-size liver grafts were transplanted orthotopically after partial hepatectomy in beagles. There were two groups: the preserved group, where portal inflow to the native liver was preserved, and the ligated group, where it was interrupted. Portal flow was measured serially and liver regeneration was evaluated on postoperative day 5. Functional competition was not observed in the preserved group. On the other hand, ligation of the native liver portal vein had no obviously detrimental effects on the remnant native liver. This leads to the conclusion that the portal vein to the native liver can be safely ligated to prevent functional competition.  相似文献   
75.
Until December 1997, 699 cases of lung cancer were resected in our institute. Four cases of invasion into the aorta and seven cases of invasion into the superior vena cava were also operated and each vessels were reconstructed. Two pneumonectomies and nine lobectomies were performed. Four cases of squamous cell carcinoma, three of adenocarcinoma, three of large cell carcinoma and one of adenosquamous carcinoma were found on pathological examination. Four cases of N0, four of N2 and two of N3 were also detected on pathological lymph node evaluation. One case was stage IV with metastasis of ipsilateral axillar lymph nodes and the others were stage IIIB. With respect to pathological curability, absolutely noncurative operation was performed in all cases involving the aorta and absolutely noncurative in four and relatively curative three in cases involving the superior vena cava. During resection and reconstruction of the aorta, three cases received temporary blood supplying bypass and one case was underwent temporary clamping. Two cases developed bilateral lower extremity paralysis. During resection and reconstruction of the superior vena cava, one case underwent intraluminal temporary blood supplying bypass, two received sideclamping and four were reconstructed with double artificial grafts for bilateral innominate veins. Two cases who underwent resection of the aorta died within one year and one is alive after nine months of operation. Five cases who underwent resection of the superior vena cava died due to cancer. One case of N0 and relatively curative is alive in free of recurrence after seven years and six months of operation and another case who had brain metastasis resected is alive after two years and two months of pulmonary operation. Careful selection should be made for resection of the aorta because the prognosis is usually poor. In the resection of the superior vena cava, good prognosis is expected in some cases (N0, relatively curative) and quality of life is expected to improve with the prevention of the superior vena cava syndrome. Aggressive resection should be considered for lung cancer invasion into the superior vena cava.  相似文献   
76.
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   
77.
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   
78.
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   
79.
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   
80.
Background: Helicobacter pylori has been reported to play an important role in the development of gastritis and gastric ulcer. Methods: This study included 168 patients with end‐stage renal disease (ESRD; 30 non‐dialysis patients, 138 patients receiving dialysis; mean duration of dialysis: 57.3 ± 61.7 months) and 138 control volunteers. We investigated the prevalence of H. pylori infection by measuring H. pylori antibody (IgG) levels. Results: The prevalence of H. pylori infection was 62.3% in the control group, 53.3% in the non‐dialysis patients, and 36.9% in the dialysis patients. The percentage decreased with a reduction of renal function. In addition, the proportion of H. pylori‐positive patients decreased with the duration of dialysis, and the antibody titre was also significantly decreased. There was no association between long‐term oral administration of H2RA (H2 receptor antagonist) and the incidence of H. pylori infection. Conclusion: Among dialysis patients, the proportion of H. pylori‐positive patients was low. An aetiological factor other than H2RA agents was suggested. Renal failure or dialysis treatment may influence H. pylori infection.  相似文献   
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