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991.
992.
We describe a modified keyhole laminoforaminotomy (LF) using anatomic landmarks on the posterior aspect of the cervical vertebral body to decompress the intervertebral foramen with minimal bone removal. Twenty-four procedures were performed at C3-4, C4-5, and C5-6; 12 at C6-7; and 3 at C7-Tl. Facets and laminae structures were identified based on relative surgical perspectives. Bony resection was limited as follows: 1) inferior limit; inferior border of the superior facet; 2) superior limit, superior border of the superior facet; 3) lateral limit, a vertical line linking the junction of the lamina-facet to the lateral end of the superior limit; and 4) lateral aspect of the dural sac. Fluoroscopy was used to confirm that the intervertebral space was reached. The amount of bony removal was quantified for the superior and inferior laminae and facets. The length of the exposed nerve root was measured. The intervertebral foramen was exposed and the intervertebral disc reached in all specimens. Fluoroscopy showed that the center of the exposure remained at the same height with the intervertebral space. The mean length of the nerve root was 4.6 mm; the mean percentage of bony resection was 21.8%, 7.5%, 11.3%, and 11.5% for the superior and inferior laminae and facets, respectively. Opening the intervertebral foramen posteriorly consistently exposed sufficient nerve root length and allowed access to the intervertebral disc. The technique offers the most direct and safest method of decompressing the intervertebral foramen while minimizing bony resection. This simple surgical procedure may help reduce postoperative morbidity.  相似文献   
993.
PURPOSE: To evaluate prospectively the safety and efficacy of totally percutaneous placement of abdominal and thoracic aortic endografts using the Prostar XL suture-mediated closure system. METHODS: From January 2002 to January 2005, we attempted to insert percutaneously all bifurcated abdominal aortic and thoracic endografts. Consecutive patients (25 men, four women), with mean age 74.9 years (range 44-84), underwent endovascular repair for 20 abdominal aortic aneurysms (AAA) and nine thoracic aortic aneurysms (repeat operation in one case). Endografts used included 21 Zenith (Cook), eight Talent (Medtronic), one AneuRx (Medtronic). For the technique, two Prostar XL 8F were used to close 22-24F access sites and one Prostar XL 10F to close 16F access sites. RESULTS: Procedural success was achieved in 21/29 (72.4%) patients and in 39/47 access sites (83%). Closure of 22-24F access sites with tandem 8F Prostar devices was successful in 23/29 (79.3%) cases. Closure of 16F access sites with 10F Prostar device was successful in 16/18 (88.8%) cases. There were seven peri-procedural failures requiring surgery to repair the femoral artery in three cases. Four access complications healed without intervention. Overall 25/29 (86.2%) patients had complete percutaneous repair. No late complications were detected during follow-up (median 17.5 months). CONCLUSIONS: Percutaneous treatment of patients with AAA and thoracic aneurysms is feasible in most cases, with a very low risk of access-related complication, providing that the operator has sufficient practical experience of this technique.  相似文献   
994.
The aim of the study was to describe the experience, current trends and management of incontinence surgery for urodynamic stress incontinence (USI) in the United Kingdom. The study was a postal questionnaire survey that was sent to a cohort of surgeons known to be performing continence surgery. The subjects addressed included the considered role of the surgeon, the total number and type of operations performed in the last year, urodynamics and physiotherapy prior to incontinence surgery, operative complications, postoperative advice and follow-up (lengths and methods). The response rate was 54%. Large variations were found in all areas. The survey provides evidence of the number of incontinence operations performed, potentially important trends and differences in the practice and management of incontinence in the United Kingdom. This survey may be helpful in making guidelines and standards for audit at regional, local and individual levels as well as recommendations for strategies to enhance professional expertise in urogynaecology in the United Kingdom.  相似文献   
995.
WT-1 positivity has previously been noted in nonneoplastic endometrial stroma. In this study we examined WT-1 expression in endometrial stromal neoplasms to ascertain whether these tumors are immunoreactive and whether this antibody might be of value in the diagnosis of these lesions. We also stained cases of cellular and highly cellular leiomyomas to investigate whether WT-1 might be of value in distinguishing these from an endometrial stromal neoplasm. We compared WT-1 staining with CD10, desmin, alpha smooth muscle actin, h-caldesmon, and AE1/3, many of these antibodies being commonly used to distinguish between an endometrial stromal and a smooth muscle phenotype. Cases of ESN (n = 5), low grade ESS (n = 14), and cellular or highly cellular leiomyoma (n = 14) were stained with the aforementioned antibodies. Cases were scored on a scale of 0 to 4+, with 4+ cases exhibiting positivity of >50% of cells. Sixteen of 19 endometrial stromal neoplasms were positive with WT-1, most (14 of 16) with 4+ positivity. Staining was nuclear (5 cases), cytoplasmic (5 cases), or combined nuclear and cytoplasmic (6 cases). All endometrial stromal neoplasms exhibited 4+ staining with CD10. Staining for alpha smooth muscle actin was present in most cases (14 of 19) and desmin and h-caldesmon were positive in a smaller number of cases (8 and 2 respectively). There was 4+ positivity with desmin in only 1 case. The 2 cases that were h-caldesmon positive both exhibited 1+ staining (<5% cells positive). Six cases were positive with AE1/3, 1 with 4+ staining. Leiomyomatous neoplasms always exhibited 4+ staining with desmin and alpha smooth muscle actin and in most cases (12 of 14) with h-caldesmon. The other 2 cases exhibited 2+ positivity. Most cases (12 of 14) were positive with WT-1 (7 of 14 with 4+ staining) and CD10 (5 of 14 with 4+ positivity). One case was positive with AE1/3. We conclude that diffuse WT-1 positivity is characteristic of endometrial stromal neoplasms and that this may be of value in diagnosis. However, WT-1 is of limited use in the distinction between an endometrial stromal and a cellular leiomyomatous neoplasm because many of the latter are also positive. This study confirms the value of h-caldesmon in the distinction between an endometrial stromal neoplasm (almost always h-caldesmon negative) and a cellular leiomyomatous neoplasm (h-caldesmon positive). Although CD10 is positive in endometrial stromal neoplasms, the commonly observed immunoreactivity of cellular and highly cellular leiomyomas with this antibody limits its diagnostic usefulness. Desmin is useful as all leiomyomatous neoplasms exhibited diffuse positivity, whereas only a small number of endometrial stromal neoplasms were focally positive and only 1 case exhibited 4+ positivity. Smooth muscle actin is of limited value since most neoplasms studied were positive. The overlapping immunophenotype of endometrial stromal and leiomyomatous neoplasms may reflect the origin of both cell types from a common progenitor within the uterus.  相似文献   
996.
Anti Orthostatic Hypokinetic posture in rats by tail suspension for 15 days (d) simulates the deconditioning effects of weightlessness on the weight bearing bones. The present study evaluates the effects of daily 4 hour (h) weight support (WS) during simulated weightlessness (S-W) in preventing these changes. Adult male albino rats were divided into three groups as (i) Control (CON, n = 12), (ii) Hind limb unweighing by tail suspension for 15 d (HU, n = 18), (iii) HU with daily 4 h WS (4 HRWS, n = 11). After 15 d tibia from all the animals were removed and subsequently dried, ashed and then calcium content of the bones were determined. HU showed reductions in the water content by 35.8%, organic matrix by 12.2% and calcium content by 33.4% of tibia. 4 h WS during S-W resulted in complete prevention of water loss and organic matrix loss and partial prevention of the loss of calcium content. Calcium content of tibia in 4 HRWS remained 15.2% less as compared to CON. These findings indicate that 4 h WS is partially successful in preventing the demineralisation effects of S-W on weight bearing bone tibia.  相似文献   
997.
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing.  相似文献   
998.
999.
1000.
Inflammatory abnormalities may be involved in the inadequate basal oxidant/antioxidant balance and local exercise-induced oxidative stress in chronic obstructive pulmonary disease (COPD) patients. The time course of oxidative stress and inflammation was investigated in 10 COPD patients and seven healthy subjects before and after local dynamic quadriceps endurance exercise at 40% of maximal strength. Venous samples were collected before, immediately after and up to 48 h after exercise. At rest, levels of an oxidant released by stimulated phagocytes, the superoxide anion, were significantly higher in patients, as were plasma levels of C-reactive protein, tumour necrosis factor-alpha and interleukin-6, inflammatory markers. An inverse relationship was found between baseline C-reactive protein levels and endurance time in patients. Six hours after exercise, superoxide anion release and levels of protein oxidation products, an index of oxidative stress, increased similarly in both groups, whereas thiobarbituric acid reactive substance levels, another index of oxidative stress, increased significantly only in patients. Plasma nonenzymatic antioxidant and inflammatory cytokine levels were unchanged by the exercise protocol. The increased baseline systemic inflammation in chronic obstructive pulmonary disease patients could be related to disturbed oxidant/antioxidant balance, and, together, these may have triggered the exercise-induced oxidative stress. The absence, however, of local exercise-induced systemic inflammation suggests that additional mechanisms explain local exercise-induced oxidative stress.  相似文献   
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