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101.
BACKGROUND: To determine whether diabetic nephropathy is a risk factor for silent cerebral infarction and whether antiplatelet drug dilazep dihydrochloride decreases the occurrence of silent cerebral infarction in type 2 diabetes patients with microalbuminuria. METHODS: Two hundred four type 2 diabetes patients (124 men, 80 women; age, median 56 years, range 42-74 years) and 60 healthy age-matched subjects (no diabetes, normal renal function) were recruited for brain magnetic resonance imaging. The diabetes patients included 40 without nephropathy (group A), 42 with microalbuminuria (20-200 microg/min) (group B), 44 with macroalbuminuria (>200 microg/min) and normal renal function (blood creatinine <132.7 micromol/L) (group C), 33 with chronic renal failure but not undergoing haemodialysis (blood creatinine >132.7 micromol/L; mean creatinine 335.9 micromol/L) (group D) and 45 undergoing haemodialysis (duration; median 4 years, range 3-6 years) (group E). RESULTS: Silent cerebral infarction was found in 20, 29, 34, 45, 53 and 8% of group A, B, C, D, E and control patients respectively. The incidence of silent cerebral infarction was increased with diabetic nephropathy. Thirty group B patients with no silent cerebral infarction were divided into two groups: (B1) 15 treated with dilazep dihydrochloride and (B2) 15 not treated with dilazep dihydrochloride. Treatment continued for 24 months. The incidence of silent cerebral infarction was significantly lower in the dilazep-treated patients (6.7%) than in the untreated patients (33.3%) (p < 0.01). CONCLUSIONS: These data suggest that diabetic renal dysfunction increases the risk of silent cerebral infarction and that dilazep dihydrochloride prevents its onset in early type 2 diabetic nephropathy patients.  相似文献   
102.
OBJECTIVES: Sphingosine 1-phosphate (Sph-1-P), a bioactive lipid derived from activated platelets, may play an important role in coronary artery spasm and hence the pathogenesis of ischemic heart diseases, since we reported that a decrease in coronary blood flow was induced by this lysophospholipid in an in vivo canine heart model [Cardiovasc. Res. 46 (2000) 119]. In this study, metabolism related to and cellular responses elicited by Sph-1-P were examined in human coronary artery smooth muscle cells (CASMCs). METHODS AND RESULTS: [3H]Sphingosine (Sph), incorporated into CASMCs, was converted to [3H]Sph-1-P intracellularly, but its stimulation-dependent formation and extracellular release were not observed. Furthermore, the cell surface Sph-1-P receptors of S1P family (previously called EDG) were found to be expressed in CASMCs. Accordingly, Sph-1-P seems to act as an extracellular mediator in CASMCs. Consistent with Sph-1-P-elicited coronary vasoconstriction in vivo, Sph-1-P strongly induced CASMC contraction, which was inhibited by JTE-013, a newly-developed specific antagonist of S1P(2) (EDG-5). Furthermore, C3 exoenzyme or Y-27632 inhibited the CASMC contraction induced by Sph-1-P, indicating Rho involvement. Finally, exogenously-added [3H]Sph-1-P underwent a rapid degradation. Since lipid phosphate phosphatases, ectoenzymes capable of dephosphorylating Sph-1-P, were expressed in CASMCs, Sph-1-P may be dephosphorylated by the ectophosphatases. CONCLUSIONS: Sph-1-P, derived from platelets and dephosphorylated on the cell surface, may induce the contraction of coronary artery smooth muscle cells through the S1P(2)/Rho signaling.  相似文献   
103.
104.
A 51-year-old Japanese woman with a solitary liver metastasis originating from a carcinoma of the ampulla of Vater was successfully treated by partial hepatectomy 19 months after curative pancreatoduodenectomy with lymphadenectomy. Histologic examination revealed a stage III well-differentiated tubular adenocarcinoma (pT2, pN1, and pM0). Postoperative serum concentrations of carcinoembryonic antigen increased exponentially to 133 ng/mL. The carcinoembryonic antigen doubling time was 63 days. Computed tomography and ultrasonography of the abdomen showed a solitary metastasis in segment VI of the liver. Since neither local recurrences nor other distant metastases were detected, the patient underwent partial hepatectomy. Histologic study confirmed the presence of a metastatic liver tumor from the ampullary carcinoma. The carcinoembryonic antigen levels returned to normal immediately after the partial hepatectomy. She was well without signs of recurrence 18 months after partial hepatectomy.  相似文献   
105.

Objective

Cervical myelopathy due to ossification of the posterior longitudinal ligament (OPLL) is induced by static factors, dynamic factors, or a combination of both. We used a three-dimensional finite element method (3D-FEM) to analyze the stress distributions in the cervical spinal cord under static compression, dynamic compression, or a combination of both in the context of OPLL.

Methods

Experimental conditions were established for the 3D-FEM spinal cord, lamina, and hill-shaped OPLL. To simulate static compression of the spinal cord, anterior compression at 10, 20, and 30% of the anterior–posterior diameter of the spinal cord was applied by the OPLL. To simulate dynamic compression, the OPLL was rotated 5°, 10°, and 15° in the flexion direction. To simulate combined static and dynamic compression under 10 and 20% anterior static compression, the OPLL was rotated 5°, 10°, and 15° in the flexion direction.

Results

The stress distribution in the spinal cord increased following static and dynamic compression by cervical OPLL. However, the stress distribution did not increase throughout the entire spinal cord. For combined static and dynamic compression, the stress distribution increased as the static compression increased, even for a mild range of motion (ROM).

Conclusion

Symptoms may appear under static or dynamic compression only. However, under static compression, the stress distribution increases with the ROM of the responsible level and this makes it very likely that symptoms will worsen. We conclude that cervical OPLL myelopathy is induced by static factors, dynamic factors, and a combination of both.  相似文献   
106.
A 79-year-old man presented with dilated cardiomyopathy and chronic atrial fibrillation. A DDD pacemaker was implanted due to sick sinus syndrome. His left ventricular ejection fraction was 23%. He was repeatedly admitted with congestive heart failure. Although cardiac resynchronization therapy was attempted, insertion of a pacing lead into the coronary sinus failed. Right ventricular bifocal pacing was done. The QRS width was shortened to 155 msec during bifocal pacing and 157 msec during right ventricular outflow pacing from 221 msec during right ventricular apical pacing. Heart failure was improved from New York Heart Association class III to II. Regional wall motion was assessed by strain of the myocardium. Bifocal pacing increased stroke volume due to improvement of longitudinal dyssynchrony of the septal and lateral walls. Bifocal pacing is effective for patients with severe congestive heart failure in whom biventricular pacing therapy has failed. Strain Doppler imaging is useful for the assessment of regional wall motion during cardiac pacing.  相似文献   
107.
BACKGROUND/AIMS: When a repeat hepatectomy is possible, it is the most effective treatment modality for recurrent colorectal liver metastasis. The aim of this study was to evaluate the surgical risks of repeat hepatectomy for liver metastasis from colorectal carcinoma. METHODOLOGY: Between 1986 and 1996, 60 patients with hepatic metastasis from colorectal carcinoma underwent surgery in the Department of Surgery I, Oita Medical University. Ten of them underwent a repeat hepatectomy. The cases of these 10 patients were studied retrospectively; in particular, postoperative complications and intraoperative blood loss were compared between the initial and second operation. RESULTS: During the second surgery, recurrence was detected adjacent to the hepatic stump in 9 of the 10 patients. During the initial surgery, 6 underwent non-anatomic resections, and 4 had anatomic resection, including 1 extended lobectomy, 1 lobectomy, and 2 segmentectomies. For the second surgery, 3 had anatomic resections, including 2 lobectomies, and 1 segmentectomy, and 7 underwent non-anatomic resections. There were no mortalities during the initial or second operation. There was no morbidity following the initial surgeries and 7 postoperative complications (intraabdominal abscess, 4 cases; biloma, 3 cases) following the second surgeries. Mean blood loss during the second operation (1044 mL) was significantly greater than during the initial operation (561 mL). CONCLUSIONS: The present results show that repeat hepatectomy for recurrent liver metastasis from colorectal carcinoma resulted in significantly greater intraoperative blood loss and postoperative complications than those of the initial surgeries. The blood loss and complications in the second operation, the one for the recurrence, were directly associated with the fact that the recurrence was so close to the hepatic stump. Since the resection line in the second surgery was adjacent to the hepatic hilus, resection of the lesion caused much more injury to the main bile duct and main portal vein than that caused by the.  相似文献   
108.
After more than two decades of experimental and clinical work, fetal surgery has become a reasonable treatment modality for selected fetuses with life-threatening anomalies. We review the literature on anatomic anomalies of the fetal lung that are amenable to fetal surgical therapy. Ultrafast fetal magnetic resonance imaging has enhanced the accuracy of prenatal evaluation. Fetal lung masses associated with hydrops are nearly 100% fatal. These lesions can be resected in utero if they are predominantly solid or multicystic. Thoracoamniotic shunting may be effective in the setting of a single large predominant cyst. Fetuses diagnosed with left congenital diaphragmatic hernia before 26 weeks' gestation, who have liver herniation and a sonographic right lung-to-head circumference ratio of less than 1.0, may benefit from temporary fetal tracheal occlusion to enhance lung growth before birth.  相似文献   
109.
A rat model of esophageal varices   总被引:12,自引:0,他引:12  
We have developed a new method for inducing portal hypertension and esophageal varices in rats--partial ligation of the portal vein after devascularization of the circumference of the left renal vein and complete ligation of the portal vein on the fifth day thereafter. Thirty rats were separated into groups of 10, control (sham operation), complete portal ligation only and complete portal ligation plus devascularization. Two weeks after the surgery, the presence of esophageal varices in rats with complete portal ligation plus devascularization was confirmed by portography and by the histological findings. The diameter (mean +/- SD) of the submucosal veins of the lower esophagus in the complete portal ligation plus devascularization group (219.4 +/- 86.6 microns) was significantly larger than that in the complete portal ligation group (99.8 +/- 53.4 microns) or in the control group (30.5 +/- 16.6 microns) (p less than 0.01). Vascular structures of the lower esophagus closely resembled those in humans with esophageal varices. This new technique is simple, rapid and reliable, and application can be made to various experimental studies on portal hypertension.  相似文献   
110.
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