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61.
Background We examined histological changes in the undersurface of the acromion in patients with symptoms of subacromial impingement, in order to clarify whether or not these changes are the main cause of rotator cuff tear.

Methods We studied 39 shoulders. The undersurface of the acromion and the coracoacromial ligament were examined by light microscopy and transmission electron microscopy.

Results The distinct four-layer structure seen in the undersurface of the acromion of normal subjects was not found in any of our patients. In patients with full-thickness cuff tear, the extent of the tear had a greater association with the degree of degeneration in the undersurface of the acromion than age or the duration of illness. There was little association between structural changes in the coracoacromial ligament and the extent of or the presence of full-thickness cuff tear, or the duration of illness, but there was a strong association with patient age.

Interpretation The histological changes in the undersurface of the acromion in patients without cuff tear were merely minute changes compared to those in patients with full-thickness cuff tear. We conclude that the advanced degenerative changes in the undersurface of the acromion result from full-thickness cuff tear.  相似文献   
62.
Pediatric burns are frequently observed: twenty-year burn analysis was performed in a single department, and 354 cases, aged 0-6 years old. The major cause of pediatric burns was scalding (68%) and hot water comprised over half of the scald burns. At 1 year old and younger, the total burn surface area (TBSA) was significantly smaller than from 1 to 6 years old (4.8+/-9.56 versus 10.5+/-18.86%, respectively, p<0.001). TBSA of scald burns was significantly greater than contact burns (8.9+/-15.76 versus 0.9+/-2.0%, respectively, p<0.05). Surgery was performed for 65 patients (18%) and 126 patients were hospitalized (34%). Compared to the first decade of analysis, the second decade had fewer patients (222 versus 142 cases) and lower severity (7.4+/-14.6% versus 6.6+/-13.26%, TBSA). Pediatric burns in younger children should be studied closely as to their causes and with further follow-up.  相似文献   
63.
BACKGROUND: "Double-insurance bypass" was recently advocated to avoid the risk of cerebral ischemia during prolonged temporary occlusion of the carotid artery. For large aneurysms needing temporary but prolonged obliteration of the internal carotid artery (ICA). We have attempted the double-insurance bypass in 15 patients and, herein, report the efficacies and limitations of the procedure, and surgical techniques to make this procedure safer. METHODS: We treated 15 patients with complex internal carotid aneurysms by clipping surgery with the aid of radial artery (RA) to proximal middle cerebral artery (MCA) bypass, so-called double-insurance bypass. We analyzed surgical results of the procedure. RESULTS: In 11 patients, the duration of temporary occlusion of the ICA could be prolonged for as long as 110 minutes (mean, 45 minutes) without any ischemic complications. One patient in the earlier period of our experience suffered extended cerebral infarction due to possible restricted blood flow through the RA, because the brachial artery was compressed by the firm shoulder joint and neighboring structures. Thereafter, we routinely monitored the blood pressure of MCA (MCABP) and never experienced such cortical infarctions. Another 3 patients, however, experienced ischemia in the territory of perforating arteries that originated from a segment that could not be perfused by the RA-MCA bypass. CONCLUSIONS: In combination with monitoring of MCABP, the double-insurance bypass can be a safer and more potent adjunctive procedure for the treatment of complex internal carotid aneurysms which require prolonged temporary occlusion of the ICA.  相似文献   
64.
A 69-year-old woman presented with a transethmoidal meningoencephalocele manifesting as gradually developing anosmia. Examinations revealed a mass in the nasal cavity associated with multiple angiomas in her lip and orbit. Neuroimaging showed meningoencephalocele extending via the ethmoid sinus to the nasal cavity. She had no history of craniofacial trauma and intranasal or intracranial operation, and no skull base tumor was detected. Frontal base reconstruction was performed with a two-layer vascularized flap to prevent cerebrospinal fluid leakage. The dural defect was repaired with the pericranial flap, and the bony defect of the cribriform plate was reconstructed using the reversed U-shaped split temporalis musculofascial flap. Transethmoidal meningoencephalocele is a rare congenital malformation and almost half of the cases are identified in the first year of life. We should be aware of this clinical pathology and avoid unexpected rhinorrhea in elderly patients. The most important aspect of the operation is watertight closure of the patent passage to the intracranial compartment. The reversed U-shaped split temporalis musculofascial flap is useful to reconstruct the midline frontal base defect.  相似文献   
65.

OBJECTIVE

To evaluate whether endothelial dysfunction and hypertension are prevented by trans-cinnamaldehyde (tCA) through the activation of endothelial nitric oxide synthase (eNOS).

METHODS

Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and stimulated with tCA to determine cell viability using the methyl thiazolyl tetrazolium assay. The effect of tCA on nitric oxide (NO) production was determined by diaminofluorescein-dyes in the absence or presence of inhibitors of eNOS, AMPK, PKA, and AKT. The effect of tCA on blood pressure was determined by the tail-cuff method in obesity spontaneous hypertension (SHR. Cg-Leprcp/NDmcr) rats. The phosphorylation of eNOS and protein expression of the insulin-signaling pathway (InsR-IRS1-PI3K-AKT) were measured by western blot.

RESULTS

tCA at concentrations less than 100 did not affect cell viability in cultured HUVECs. Stimulation with tCA promoted NO release in a time-dependent manner compared with the control group. tCA-treated HUVECs also significantly increased AKT-Ser473 and eNOS- Ser1177 phosphorylation. In SHR-CP rats, treatment with tCA at a dose of 40 mg/kg/day for 6 weeks markedly reduced the systolic blood pressure and diastolic blood pressure, increased the phosphorylation of AKT and eNOS, and increased urinary nitric oxidation.

CONCLUSION

tCA attenuated endothelial dysfunction and reduced blood pressure in SHR-CP rats. The underlying mechanisms may involve the increase in AKT and eNOS phosphorylation and the release of eNOS-derived NO.  相似文献   
66.
Mutant herpes simplex virus-mediated suppression of retinoblastoma.   总被引:2,自引:0,他引:2  
PURPOSE: To test the ability of a mutant herpes simplex virus (HSV) hrR3 to inhibit growth of Y79 human retinoblastoma in vitro and in vivo. METHODS: Cultured Y79 cells were infected with multiplicities of infection (MOI) ranging from 0.004 to 0.1 of hrR3. Surviving cells were counted using trypan blue dye exclusion. Using X-gal staining, expression of the lacZ gene was examined in vitro on day 3 postinfection to evaluate viral replication. Nude mice harboring Y79 tumors subcutaneously received an intraneoplasmic injection of 5 x 10(7) plaque-forming units of hrR3. The tumor sizes were measured weekly. Expression of the lacZ gene was also examined on one week postinfection. RESULTS: There are 31% and 13% cells surviving in cultured Y79 cells infected by hrR3 at an MOI of 0.1 on days 3 and 5 postinfection respectively compared to those of mock-infected cells. Also more than 70% of Y79 cells were stained with X-gal at an MOI of 0.1 which demonstrated active viral replication in vitro. Virus-treated subcutaneous tumors were smaller than control tumors (p<0.05, Student's t-test) on days 14, 21, and 28 postinfection. Positive X-gal staining was also observed in the tumor nodule which was challenged with this viral vector. CONCLUSIONS: We have demonstrated that hrR3 is capable of inhibiting Y79 tumor growth both in cell culture and in nude mice. These data suggest that gene therapy using this mutant HSV vector can be a new supplementary therapeutic modality for retinoblastoma.  相似文献   
67.
Six cochlear implant recipients with hearing aids in the opposite ear were studied to survey binaural advantage. They were examined in separate tests by using a hearing aid alone, cochlear implant alone, and by using both devices (bimodal condition). Test items used were the Japanese monosyllable word list 67--S and Japanese HINT. Statistically significantly results were obtained in the bimodal condition, three out of six subjects were successful in the monosyllable word test and all successful in the Japanese HINT. We conclude that all subjects enjoyed binaural advantage in speech perception in bimodal condition with no conflict at the recognition level; even when different sounds from cochlear implant and contralateral hearing aid were received. The plasticity of the brain is thought to be of importance in the bimodal condition.  相似文献   
68.
Photodynamic therapy (PDT) with topical application of 5-aminolaevulinic acid (ALA) is a promising new treatment option for the management of various cutaneous malignancies. Generally, topical ALA-based PDT has relatively insignificant adverse effects of transient character; these include itching, stinging or burning pain and slight to moderate erythema. We describe the first case of photocontact urticaria induced by topical ALA-based PDT for the treatment of unilesional mycosis fungoides. Although the first treatment session resulted merely in mild erythema, the second PDT caused marked urticaria corresponding to the PDT-applied area with an intolerable stinging sensation. A photopatch test demonstrated that black light and visible light irradiation after topical ALA provoked an urticarial reaction in the patient's uninvolved skin. These observations suggested an allergic pathogenesis for the wheal formation induced by PDT with topical ALA in this case. Photocontact urticaria should be considered as a possible adverse effect in ALA-based PDT.  相似文献   
69.
PURPOSE: To diagnose an atypical retinal degenerative disease with choroidal neovascularization by means of gene diagnosis. CASE: A 47-year-old woman had good visual acuity at the first examination. She had scattered chorioretinal degeneration and pigmentation in the peripheral retina. There was a symmetrical visual field defect in the upper and temporal periphery in both eyes. Seven years later, choroidal neovascular membrane (CNV) developed in the fovea of her left eye and visual acuity deteriorated to 0.4 in this eye. Optical coherence tomography revealed type 2 CNV with minimal subretinal fluid. Fluorescein angiography showed very little leakage from the CNV. We used denaturing high performance liquid chromatography(DHPLC) to perform gene diagnosis and found a peripherin/RDS gene mutation of Gly167-Ser. CONCLUSION: Our case had moderate peripheral retinal degeneration with CNV. It is possible that cases like this tend to be misdiagnosed as AMD (age-related macular degeneration) or CNV with high myopia. Evaluation of the gene mutation was useful for diagnosis in this case.  相似文献   
70.
Transurethral resection of the bladder neck was performed in 6 female patients with neurogenic bladders who presented with a large volume of residual urine and bladder neck obstruction on voiding cystourethrography without detrusor hyperreflexia on cystometry. In 4 of the patients, transurethral sphincterotomy was performed concomitantly. Five of the patients demonstrated significant improvement in bladder emptying and 4 did not need self-catheterization. No complications of the operation were observed.  相似文献   
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