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991.
BACKGROUND AND AIM OF THE STUDY: Treatment for hypertrophic obstructive cardiomyopathy (HOCM) has been reported; however, there has been no report on the characteristics of medication-responsive and -refractory hypertrophic obstructive cardiomyopathy (HOCM). Using the classification of systolic anterior movement (SAM) which has been previously reported, we tried to identify the characteristics and use them to treat HOCM appropriately. METHODS: The clinical, echocardiographic, catheterization, and surgical data of 29 hospitalized patients with HOCM during 1980 to 1999 were analyzed retrospectively. We classified SAM in all patients by echocardiography. Nineteen patients improved with medical treatment (medical group), and 10 patients underwent surgical treatment because of ineffectiveness of medication (surgical group). We studied the relation between types of SAM and medical/surgical groups, and examined the relation between types of SAM and the surgical methods. RESULTS: Type I SAM was significantly more frequent in the medical group, while type II SAM was more frequent in the surgical group (p = 0.047). Patients in the surgical group underwent mitral valve replacement (MVR), myectomy, or a combination of MVR and myectomy. Left ventricular outflow gradient (LVOG) of over 100 mmHg was recognized in almost all patients with type II SAM. CONCLUSIONS: It was suggested that patients with medication-responsive HOCM tended to have type I SAM and those with refractory HOCM tended to have type II SAM. We consider that in type I SAM, if the position of the papillary muscles changed with medication or myectomy, shift of the chordae and type I SAM were reduced or disappeared. However, in type II SAM, even if the position of the papillary muscles changed, SAM did not disappear because lifting of the mitral leaflets remained. It is therefore suggested that patients with type II SAM should undergo at least MVR.  相似文献   
992.
A 74-year-old man with chronic renal failure under hemodialysis via the left upper extremity underwent an off-pump coronary artery bypass (OPCAB). The left internal thoracic artery (LITA), which was harvested in a skeletonized manner, was anastomosed to the left anterior descending artery (LAD). Postoperatively, he complained of chest pain only during dialysis. Angiography revealed a kinking in the LITA. However, myocardial scintigraphy revealed no ischemia. One year after OPCAB, left ventriculography revealed akinesis and myocardial scintigraphy revealed no viability in the anterior wall. This suggested that the viability was lost due to graft kinking and steal phenomenon during hemodialysis. If the length of the skeletonized ITA graft is redundant, kinking of the graft rarely occurs after the chest is closed. We also suggest that to avoid the kinking of the ITA graft, fibrin glue should be used to paste the ITA graft running in a gentle curve.  相似文献   
993.
OBJECTIVE: Preceding selective cerebral perfusion (P-SCP) is a method whereby SCP and systemic perfusion start simultaneously, and the arch vessels are clamped. Cerebral circulation is isolated from systemic circulation to avoid cerebral embolization due to detachment of atherosclerotic material from the aorta, caused by the "sandblasting" effect of high-velocity jets of blood exiting the aortic cannula. However, neither the safety of SCP at normothermia nor the influence of extended SCP time has been sufficiently clarified. To clarify the safety of P-SCP, the comparison study of P-SCP and conventional SCP (C-SCP) was performed retrospectively. METHODS: Fifty-seven patients (C-SCP group: 29 patients; P-SCP: 28 patients) underwent surgery between 1992 and 2002. RESULTS: Nine (15.8%) in-hospital death occurred; 4 in the C-SCP group (13.8%) and 5 in the P-SCP group (17.9%) (NS). The SCP time was 136.6 +/- 68.5 minutes in the C-SCP group and 195.8 +/- 30.7 minutes in the P-SCP group (p < 0.05). One patient in each group exhibited postoperative neurological dysfunction. CONCLUSION: It may be little dangerous to initiate the SCP with normothermia. P-SCP may be useful in cases in which there is pedunculated atherosclerotic material, or mural thrombus in the ascending and arch aorta.  相似文献   
994.
PURPOSE: We induced radio frequency (RF) lesions in the neuronal pathway leading from the forebrain to the pontine micturition center (PMC) to produce a rat model of bladder overactivity. We studied the effects of gamma-aminobutyric acid agonists (diazepam and baclofen) and glutamate receptor antagonists (MK-801 maleate and GYKI52466 [1-(4-aminophenyl-D-4-methyl-7,8 methylenedioxy-5H-2,3-benzodiazepine] hydrochloride) on the cystometrogram and developed a possible explanation of the neuronal mechanisms underlying RF lesion induced bladder overactivity. MATERIALS AND METHOD: Seven-week-old male Sprague-Dawley rats were anesthetized with sodium pentobarbital and RF lesions were produced in the nuclei basalis. Five days later bladder contractions were induced by infusing fluid into the bladder and cystometrograms were measured in conscious rats. RESULTS: The micturition interval (MI) in rats subjected to RF lesioning was significantly shorter than that in sham operated control rats. Diazepam (0.1 and 1 mg/kg intraperitoneally), baclofen (1 mg/kg intravenously) and MK-801 (0.1 and 1 mg/kg intravenously) did not change or shortened MI in control rats but it prolonged MI in lesioned rats. GYKI52466 (0.5 and 1 mg/kg intravenously) weakly prolonged MI in lesioned rats. CONCLUSIONS: We consider that RF lesioning causes interruption of the inhibitory GABAergic neurons that lead from the forebrain to the PMC. This results in the activation of N-methyl-D-aspartate receptors in the PMC that are involved in the facilitation of voiding.  相似文献   
995.
Tanaka K  Shimada H  Kubota K  Ueda M  Endo I  Sekido H  Togo S 《Surgery》2005,137(2):156-164
BACKGROUND: Consensus remains to be achieved concerning prehepatectomy neoadjuvant chemotherapy as a treatment strategy for multiple bilobar colorectal liver metastases, in part because the effect of prehepatectomy neoadjuvant chemotherapy has not been determined pathologically. We investigated the efficacy of prehepatectomy intra-arterial chemotherapy for multiple bilobar colorectal cancer metastases to the liver. METHODS: Clinicopathologic data for 37 consecutive patients with > or =5 bilobar liver metastases from colorectal cancer who underwent hepatectomy were analyzed retrospectively with respect to long-term outcome and histological findings in resected liver tumors. RESULTS: In the 15 patients receiving neodadjuvant chemotherapy (NEO+ group), liver metastases progressed in 2 patients, remained stable in 8 patients, responded more than 50% in 4 patients, and responded completely in 1 patient (combined response rate, 33.3%). Overall and hepatic recurrence-free survival tended to be higher in responders than in nonresponders ( P = .053). Microscopic invasion of the portal vein, hepatic vein, and bile ducts near liver tumors was less frequent according to use of neoadjuvant chemotherapy and responsiveness to the therapy (responders, 20.0%; patients not receiving neoadjuvant therapy [NEO-], 72.7%; P < .05). Such microscopic invasion independently predicted hepatic recurrence by multivariate analysis ( P = .011). CONCLUSIONS: A neoadjuvant chemotherapy-associated decrease in microscopic vasculobiliary invasion by metastatic liver tumors was related to clinical response and favorable outcome.  相似文献   
996.
997.
OBJECTIVE: Misplacement of subclavian vein catheters has been reported. We assessed the rate of misplacement of a subclavian vein catheter with and without a novel stylet. METHODS: A prospective, randomized, controlled clinical trial was conducted between September 2001 and June 2003 in a university hospital. Two hundred sixteen adult patients were enrolled to receive subclavian vein catheterization under non-emergency conditions. Patients were randomly assigned to undergo right subclavian vein catheterization with the stylet (n = 109, stylet group) or without the stylet (n = 107, control group). The rate of subclavian vein catheter misplacement was determined and risk factors for failure and complications were analyzed. RESULTS: There was no incidence of catheter misplacement in the stylet group, but this occurred in 12 patients in the control group in whom the catheter was misplaced into the ipsilateral internal jugular vein (0% versus 11.2%, P = 0.0003). In multivariate analyses, use of the stylet (odds ratio = 0.062, 95% confidence interval = 0.008 to 0.495, P = 0.009) and a close to average body mass index (odds ratio = 0.73, 95% confidence interval = 0.54 to 0.98, P = 0.038) were associated with low risks of complications and failure, respectively. CONCLUSIONS: This stylet is useful for decreasing the incidence of misplacement of subclavian vein catheters. Body mass index is predictive of failed vein puncture.  相似文献   
998.
OBJECTIVES: The goal of our study was to determine whether altered adenosinergic mechanisms contribute to the depressed ventilatory response observed in obese Zucker rats. RESEARCH METHODS AND PROCEDURES: Eight lean and eight obese Zucker rats were studied at 7 to 8 weeks of age. Ventilation (V(E)) during room air, during 5-minute hypercapnic (7% CO(2), balance O(2)), and during 30-minute sustained hypoxic (10% O(2)) exposures were sequentially measured by the barometric method on three separate occasions after the randomized blinded administration of equal volumes of either saline (control), 8-(p-sulfophenyl)-theophylline (8-PST, 7 mg/kg, peripheral adenosine antagonist), or aminophylline (AMPH, 15 mg/kg, peripheral and central adenosine antagonist). RESULTS: During room air and hypercapnic exposures, AMPH (but not 8-PST) significantly (p < 0.05) increased V(E) in both lean and obese rats. During acute (2 minute) hypoxic exposure, 8-PST (but not AMPH) significantly depressed V(E) in lean rats. In contrast, AMPH (but not 8-PST) selectively increased V(E) in obese rats. During sustained (10 to 30 minutes) hypoxic exposure, neither AMPH nor 8-PST administration altered V(E) in lean rats. In contrast, AMPH (but not 8-PST) selectively increased V(E) during the late response in obese rats. DISCUSSION: Our findings indicate that obese rats possess altered adenosinergic modulation of ventilatory responses to acute and sustained hypoxia in two opposite ways. We conclude that the reduced hypoxic ventilatory response observed in obese Zucker rats is attributed to depressed adenosinergic peripheral excitatory mechanisms and to enhanced adenosinergic central depression mechanisms, both of which contribute to the blunted ventilatory response in obesity.  相似文献   
999.
The authors report two cases of patients with lumbar ossification of the posterior longitudinal ligament (OPLL). One patient underwent surgery via the single posterior approach, and the other patient underwent combined anterior-posterior surgery. The authors consider the anterior approach for excision of the ossified lesion to be the most reasonable for treatment of lumbar OPLL. It is extremely important, however, to select the surgical procedure according to the individual patient's condition.  相似文献   
1000.
PURPOSE: To investigate a new modality of mucosal vaccines, we evaluated the effectiveness of intragastric immunization for inducing a mucosal immune response in the gastrointestinal tract. METHODS: Mice were immunized with beta-galactosidase (beta-gal) and synthesized oligodeoxynucleotides containing a CpG motif (CpG-DNA) by intragastric injection, and the immune response was compared with those induced by 3 other immunization forms: intranasal, oral, and intradermal. RESULTS: Intragastric immunization with beta-gal and CpG-DNA induced significant anti-beta-gal fecal IgA production at 2 weeks; however, at 4 weeks the response was lacking. In contrast, intranasal immunization with beta-gal and CpG-DNA induced the highest anti-beta-gal fecal IgA production at 4 weeks. CONCLUSION: Although intragastric immunization with protein and CpG-DNA induces a mucosal immune response in the gastrointestinal tract, intranasal immunization is the most effective to induce both mucosal and systemic immune responses. This finding may increase the possibility for developing vaccines against mucosal pathogens, especially Helicobacter pylori.  相似文献   
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