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1.
We describe two patients with lesions clinically resembling pseudoxanthoma elasticum and histologically exhibiting focal elastosis. with normal-appearing elastic fibres in the mid- and deep dermis. We consider that these skin lesions represent a previously undescribed entity, whose pathogenesis appears to be related to the ageing process.  相似文献   
2.
SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC50 was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.  相似文献   
3.
The most serious problem regarding a laparoscopic partial nephrectomy is how to perform bloodless excision without causing renal ischemia in a limited working space. We report the case of a 65-year-old man with left small renal cell carcinoma in the posterior mid zone who underwent a laparoscopic partial nephrectomy through a retroperitoneal approach by carrying out the ligation of the tumor-feeding artery, but without clamping the renal pedicle. Both preoperative abdominal computed tomography (CT) and intraoperative ultrasonography revealed the tumor to be fully encapsulated. The tumor-feeding artery could be exposed by dissection from the renal hilum and, after an arterial ligation, tumor resection with a safety margin was smoothly performed with minimal bleeding. Postoperatively, CT revealed a limited defect of the renal parenchyma and excretory pyelography showed no urine leakage or urinary tract obstruction. The preoperative and postoperative creatinine levels were 0.66 and 0.69 mg/dL, respectively. As a result, a tumor-feeding artery ligation with a laparoscopic partial nephrectomy for left renal cell carcinoma in the posterior mid zone is considered to be an effective surgical modality which avoids renal ischemia and pelvic heat injury.  相似文献   
4.
Background: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. Methods: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. Results: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal‐looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal‐looking surface or non‐elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable‐sized vacuoles, and were related to lymph follicles. Conclusion: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.  相似文献   
5.
To clarify the pathogenesis of the widely known but obscuresyndrome of sudden death with hepatic fatty metamorphosis observedin alcohol abusers, we have scrutinized both the clinical andpathological data of 11 subjects who died under such circumstancesbetween 1987 and 1993. Death followed several days of uninterrupteddrinking often with little dietary intake. The notable clinicalfeatures on arrival at the emergency room were disturbance ofconsciousness (11/11), hypotension (47/6), hypothermia (3/5),hypoglycaemia (8/11), metabolic acidosis (6/6), renal dysfunction(11/11), and hyperammonaemia (5/5). The common hepatic pathologywas the extensive appearance of numerous microvesicular fattydroplets in the hepatocytes together with varying degrees ofmacrovesicular fatty change; four subjects had an underlyingcirrhosis. Death undoubtedly results from a variety of metabolicdisturbances triggered by the combination of massive ethanolintake and starvation. The appearance of extensive microvesicularfatty change superimposed on macrovesicular fatty change wasconsidered to be an associated phenomenon  相似文献   
6.
AIM: The aim of the present study was to investigate the safety and efficacy of endoscopic laser therapy for transitional cell carcinoma (TCC) of the upper urinary tract. METHODS: Tumors of the renal pelvis and ureteropelvic junction were detected by ureteroscopy. The tumors were subjected to biopsy, and after TCC was diagnosed, endoscopic laser therapy (Neodymium-YAG and Holmium-YAG) was conducted using a 6.9 Fr. flexible ureterorenoscope. RESULTS: From January 1997 to April 2002, six patients underwent ureteroscopic treatment. Tumor grade was 1 in four patients and 2 in two patients. Average tumor size was 1.45 cm. Endoscopic treatment was chosen for two patients because of the high medical risk associated with open surgery. Another patient underwent diagnostic ureteroscopy, followed immediately by endoscopic treatment. A further three patients elected to undergo ureteroscopic treatment. One patient with large (3 cm), multifocal and incompletely treated tumors died of metastatic disease 22 months after the initial operation. One patient requested nephroureterectomy one month after endoscopic treatment, and pathological examination of the resected specimen revealed no tumor. The other four patients have been followed up for a mean period of 14 months after initial treatment. Recurrence occurred in one patient, and was successfully treated by repeat endoscopic resection. None of the patients required blood transfusion or emergency open surgery. CONCLUSION: Ureteroscopic treatment of small, localized, low-grade TCC of the upper urinary tract is now a safe and feasible alternative to nephroureterectomy in selected patients.  相似文献   
7.
Summary In normal human skin, immtmoreactive thrombomodulin (TM) is expressed in a strict differentiation related pattern. solely in suprabasal spinous layer keratinocytes. To evaluate the polential application of TM as a differentiation marker for keratinocyte-derived skin tumours, we have studied immunohistopathological, biochemical and functional TM activities in various skin tumours. Immunoreactive, full sized and enzymatically active TM was expressed in keratinocyte-derived skin tumours (squamous cell carcinoma, seborrhoeic keratosis and partly Bowen's disease), as well as normal epidermal keratinoeytes and endothelial cells. However, no TM was detected in basal cell carcinotnas, senile keratosis or non-squanious epithelial tumours such as malignant melanoma, naevus pigmentosus and Paget's disease. Interestingly, decreased expression was observed in verruca vulgaris. These findings suggested that differentiation-dependent TM expression was restricted to epithelial skin tumours and undetectable on neural crest derived tumours. TM is a differentiation marker for spinous layer keratinocytes and is a useful tool in histopathological study of epithelial tumours.  相似文献   
8.
Fetal anaesthesia was performed 5 times in 1 patient to treat pleural effusions, obtain fetal blood sampling, provide albumin infusion, and establish and replace a pleuro-amniotic indwelling shunt catheter under ultrasound guidance. A maternal epidural catheter was placed and used for epidural anaesthesia for the first 4 anaesthetics. Fetal administration of pancuronium 0.15 mg·kg?1 via the umbilical vein or 0.25 mg·kg?1 intramuscularly was enough to produce immobilization without maternal effect. However, maternal pretreatment with intravenous diazepam and fentanyl was required for fetal sedation and analgesia, which was necessary for accurate and safe injection, and for suppression of fetal stress.  相似文献   
9.
Four cases of Ischemic enterocolitis without arterio–occlusive lesion were described. Three cases were associated with sigmoid colon carcinomas. Ischemic lesions developed anal to the carcinomas in two cases, and oral to sigmoidostomy to relieve intestinal obstruction by carcinoma in one case. One other case was associated with inguinal hernia. Grossly, ischemic lesions involved relatively short intestinal segments, and the ischemic colonic lesions were not related to teniae coli. Extensive veno–occlusive lesions were discovered in a case of ischemic stricture of the ileum, which had been incarcerated in the right inguinal hernia. Reversible mechanical occlusion of the intestinal vessels caused by transient or recurrent intestinal strangulation is the most probable cause of these ischemic lesions., ACTA PATHOL. JPN. 33: 249–256, 1983.  相似文献   
10.
Effect of relaxation training on cardiac parasympathetic tone   总被引:8,自引:0,他引:8  
To examine the hypothesis that the relaxation response is associated with an increase in cardiac parasympathetic tone, the frequency components of heart rate variability during relaxation training were investigated in 16 college students. Electrocardiograms and pneumograms were recorded during a 5-min baseline period followed by three successive 5-min sessions of the autogenic training (relaxation) or by the same periods of quiet rest (control), while subjects breathed synchronously with a visual pacemaker (0.25 Hz). Although neither the magnitude nor the frequeney of respiration showed a significant difference between relaxation and control, the amplitude of the high-frequency component of heart rate variability increased only during relaxation (p= .008). There was no significant difference in the ratio of the low-frequency (0.04–0.15 Hz) to the high-frequency amplitudes. The increased high-frequency amplitude without changes in the respiratory parameters indicates enhanced cardiac parasympathetic tone. Thus, our results support the initial hypothesis of this study. Enhanced cardiac parasympathetic tone may explain an important mechanism underlying the beneficial effect of the relaxation response.  相似文献   
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