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21.
We successfully replanted five amputated legs in five patients and followed the patients for two years or more (average, six years and three months). Although some patients found it impossible to squat and to run because of joint contractures, muscle weakness, or deformities of the foot, all patients could perform other activities without difficulty. None had important pain or any intolerance to cold, and all were satisfied with the results of the replantation.  相似文献   
22.
Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized.  相似文献   
23.
We report a case of groove pancreatitis (GP) associated with a true pancreatic cyst. An 81-year-old man who had suffered epigastric pain for 4 months was referred to Saisekai Kure Hospital. Computed tomography and endoscopic retrograde pancreatography showed a cystic lesion in the groove area of the pancreas. Serum amylase elevation and imaging findings suggested GP due to the cyst. Six weeks of medical treatment did not improve the clinical symptoms. Therefore, pancreatoduodenectomy was performed. Histologic examination revealed a true cyst with intraluminal necrosis, which produced a protein plug that obstructed the Santorini duct. The parenchyma surrounding the groove area showed marked fibrosis and inflammatory cell infiltration. GP due to true pancreatic cyst was diagnosed. Although GP is usually caused by overconsumption of alcohol, which leads to changes in the pancreatic juice and the ultimate blockage of pancreatic outflow, the histologic features in our patient suggest that true pancreatic cyst stands as a secondary cause of GP.  相似文献   
24.
25.
Endothelin, a 21-amino acid peptide produced by vascular endothelial cells, caused a sustained constriction of isolated large cerebral arteries of cats in a dose-dependent manner. The increased tone of the tissue did not return to the resting level after repeated washings. No vasodilator response was evoked by endothelin in the presence of an active tone. The contractile response of cerebral arteries was not inhibited by rubbing of the endothelium, cold storage denervation or indomethacin. In contrast, nicardipine or diltiazem antagonized the endothelin-induced contraction non-competitively. No contraction was evoked by endothelin in a Ca2+-free solution while the addition of Ca2+ ions in the presence of endothelin in a Ca2+-free solution caused a sustained contraction. Ca2+-induced contraction in the Ca2+-free solution containing endothelin was also inhibited by nicardipine. Therefore, endothelin causes a direct contraction of the smooth muscles of cat cerebral arteries, probably by activating the influx of Ca2+ ions through L-type Ca2+ channels of smooth muscles.  相似文献   
26.
A 47-year-old male was concerned with a large AVM involved extensively in the parietal region and the posterior fossa. Radiological examinations showed multiple radiolucencies in the parietal and occipital bone and torturous vascular nets (nidus) in those bones on the angiograms. Nidus was found also in the dura mater in the posterior fossa. Therefore, this case seemed to be an extremely rare case of calvarial AVM in the parietal region with the mixed calvarial dural AVM in the posterior fossa. His symptoms were bruit, transient hemiparesis and Gerstmann's syndrome in addition to the symptoms due to raised intracranial pressure. Favorable results of therapies could be attained by extensive exfoliation of dura mater from the cranial bone and incision of proximal dura mater in the sinus.  相似文献   
27.
Amlodipine is a dihydropyridine calcium channel blocker that is widely used for the treatment of hypertensive patients and has an antioxidant effect on vessels in vitro. The aim of the present study was to examine whether treatment with amlodipine reduced oxidative stress in the brains of stroke-prone spontaneously hypertensive rats (SHRSP). The animals received amlodipine, nicardipine or hydralazine for 30 days in their drinking water. Levels of thiobarbituric acid-reactive substances (TBARS) in the brain (cortex, cerebellum, hypothalamus, and brainstem) were measured before and after each treatment. Systolic blood pressure decreased to similar levels in the amlodipine-, nicardipine-, and hydralazine-treated groups. Urinary norepinephrine excretion was significantly reduced in SHRSP after treatment with amlodipine, but not with nicardipine or hydralazine. Levels of TBARS in the cortex, cerebellum, hypothalamus, and brainstem were significantly higher in SHRSP than in Wistar-Kyoto rats (WKY), and were reduced in amlodipine-treated, but not in nicardipine- or hydralazine-treated, SHRSP. Electron spin resonance spectroscopy revealed increased levels of reactive oxygen species in the brains of SHRSP, which were reduced by treatment with amlodipine. Intracisternal infusion of amlodipine also reduced systolic blood pressure, urinary norepinephrine excretion, and the levels of TBARS in the brain. These results suggested that oxidative stress in the brain was enhanced in SHRSP compared with WKY rats. In addition, antihypertensive treatment with amlodipine reduced oxidative stress in all areas of the brain examined and decreased blood pressure without a reflex increase in sympathetic nerve activity in SHRSP.  相似文献   
28.
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury.  相似文献   
29.
The major glomerular abnormalities in hypertensive nephrosclerosis are described as glomerular obsolescence (GO), glomerulosclerosis (GS), and glomerular collapse (GC). However, glomerular cellular changes caused by hypertensive insults have not been well analyzed. Using an immunoenzyme method, we examined eleven biopsy samples from patients with hypertensive nephrosclerosis for two synthetic and secreting phenotypes, a-smooth muscle actin (alpha-SMA) and collagen type III (Col. III), and two apoptotic phenotypes, pro-apoptotic molecule Bax and anti-apoptotic molecule BcI-2. Together with the glomerular and vascular changes and interstitial fibrosis (IF) area, the results were scored quantitatively and semi-quantitatively and compared to the clinical findings, which included systolic blood pressure (SBP), mean arterial pressure (MAP), serum creatinine levels (sCr) and creatinine clearance (Ccr), using univariate and multivariate analyses. As a result, GS was frequently observed in the mild-to-moderate hypertensive group (140 < or = SBP<180 mmHg), whereas GC was positively correlated with SBP. Furthermore, there was a positive correlation of GS with mesangial alpha-SMA and Col. III, suggesting that GS was the reflection of these synthetic and secreting phenotypic changes in mesangial cells. Endothelial Bax was positively correlated with Ccr (p<0.01); in contrast, podocytic Bax was positively correlated with sCr (p<0.05) and showed a tendency to correlate with MAP (p=0.054). In conclusion, these findings support the view that mesangial synthetic and secreting phenotypic changes may be a reflection of cellular activation caused by mild-to-moderate hypertension and that apoptotic phenotypic expression in podocytes, rather than endothelial cells, may be related to the development of a severe form of hypertensive nephrosclerosis.  相似文献   
30.
OBJECTIVE: It has been observed that a systemic inflammatory response after on-pump coronary artery bypass grafting (CABG) participates in the pathogenesis of postoperative atrial fibrillation (AF). In patients undergoing off-pump CABG, it is plausible that inflammation is associated with the development of postoperative AF. The present study examined relation of proinflammatory cytokines, which play an important role in the upstream of inflammatory cascade, to the development of AF after off-pump CABG. METHODS: The present study included 39 patients undergoing off-pump CABG. Tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, and IL-8, were measured by enzyme-linked immunosorbent assay, on anesthetic induction, after sternotomy before anastomoses, at the completion of anastomoses, 3 and 6h thereafter, and on postoperative days (POD) 1-4. C-reactive protein (CRP) was also measured by turbidimetric immunoassay, preoperatively, and on POD 1, 2, 3, 6, 9, and 13. RESULTS: Eleven patients (28%) developed postoperative AF. Patients with postoperative AF were older (70+/-6.4 years vs 60+/-8.8 years, P=0.001); however, there was no difference in other pre- and perioperative variables. TNF-alpha level did not change during the study period. However, IL-8 and CRP levels significantly increased after the surgery, although there was no significant difference between the two groups. IL-6 level also increased after the surgery with its peak at 6h after the completion of anastomoses. IL-6 levels of 3 and 6h after anastomoses were significantly higher in patients with postoperative AF (360+/-143 pg/ml vs 230+/-94 pg/ml, P=0.0047, 435+/-175 pg/ml vs 247+/-102 pg/ml, P=0.0005, respectively). Logistic regression analysis indicated that the highest quartile of IL-6 level immediately after the surgery (odds ratio 7.63; 95% CI, 1.06-54.9; P=0.04) and age (odds ratio 1.18; 95% CI, 1.01-1.39; P=0.04) independently predict postoperative AF. Furthermore, the maximum level of IL-6 immediately after the surgery significantly correlated to age and intraoperative blood loss (r=0.04, P=0.01, and r=0.47, P=0.04, respectively). CONCLUSIONS: Advanced age was a major risk factor for postoperative AF. Furthermore, inflammatory response induced by surgical trauma was also associated with the development of AF after off-pump CABG.  相似文献   
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