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61.
This study measured the changes in moment arm length of thumb motor tendons after simulated ligamentous instability and subsequent reconstruction of the trapeziometacarpal joint. Excursions of thumb motor tendons were measured simultaneously with the trapeziometacarpal joint angulation during flexion to extension and abduction to adduction motion. Tendon moment arms were calculated based on joint and tendon displacement techniques in the intact joint, after sequential sectionings of the capsuloligamentous restraints, and after the reconstruction procedure of Eaton and Littler. The results showed that moment arms of the abductor pollicis longus and extensor pollicis brevis tendons increased significantly as compared with those for normal joints during flexion to extension motion after sectioning the palmar capsuloligamentous components. After the ulnopalmar structures were cut, the moment arm of the extensor pollicis longus tendon had a statistically significant increase during abduction to adduction motion, and those of the extensor and flexor pollicis longus tendons decreased significantly during flexion to extension motion. Changed moment arms were restored to a normal level after the ligamentous reconstruction. These results indicate that ligamentous disruptions alter the mechanical balance of thumb motor tendons, which may contribute to joint deformities observed in trapeziometacarpal joint arthritis. Restoring joint stability is important to correct mechanical imbalance of the tendons.  相似文献   
62.
PURPOSE: Tumor necrosis factor-alpha (TNF-alpha) is involved in oncogenesis of several cancers. The purpose of this study was to investigate whether genotype changes of TNF-alpha promoter regions (-238, -308) and at the 488 region are associated with human prostate cancer. MATERIALS AND METHODS: The DNA from 73 cases of human prostate cancer was analyzed by allele-specific polymerase chain reaction to characterize the genotype changes of three regions of the TNF-alpha gene in prostate cancer patients. We also determined the genotype frequency in these patients. The relative risk of variant genotype was calculated by comparing with our previous data from healthy controls. RESULTS: Genetic changes were detected in 15.1% (11/73) of prostate cancer samples at 488 region of TNF-alpha. Seventy-three percent (53/73) of the patients showed genotype GA at -308 region of TNF-alpha. Genotype GA at 488 region in TNF-alpha was observed in 73% (53/73) of the cancer and 71% (52/73) of the normal tissue. The relative risks of incidence for prostate cancer was 14-fold higher in people with genotype GA at -308 region of TNF-alpha. The relative incidence for prostate cancer was a 17-fold higher in-patient with genotype GA at 488 region of TNF-alpha. Genotype GA at -308 of TNF-alpha was related to higher clinical tumor stage of prostate cancer than genotype G (p <0.05). CONCLUSIONS: The present study demonstrates, for the first time, that the genotype changes in -308 and 488 regions of TNF-alpha are associated with prostate cancer.  相似文献   
63.
PURPOSE: We present our experience with collagen injection for treating urinary incontinence after cystectomy and orthotopic bladder substitution in women. We discuss the efficacy of collagen injection, specific complications and subsequent definitive therapy. MATERIALS AND METHODS: We performed cystectomy and orthotopic bladder substitution in 2 women for muscle invasive transitional cell carcinoma of the bladder. In each case new onset stress urinary incontinence developed after surgery that was refractory to conservative therapy. Intrinsic sphincter deficiency was diagnosed in each patient by video urodynamic studies. Initial treatment involved transurethral collagen injections but subsequent intervention was required due to resultant complications and primary therapy inefficacy. RESULTS: Collagen (3.5 cc per session) was injected in 1 case at 2 treatment sessions and in the other at 3. Incontinence symptoms did not significantly improve in either patient and a new onset vesicovaginal fistula developed 2 days and 1 month after collagen injection, respectively. Subsequently in each case 1-stage transvaginal primary fistula repair was done in multiple layers with a pubovaginal sling procedure. Six months after repair there has been no recurrent fistula and the women remain hypercontinent, requiring intermittent self-catheterization. They are satisfied with their eventual lower tract function and overall outcome. CONCLUSIONS: Collagen injection for type 3 stress urinary incontinence after cystectomy and orthotopic bladder replacement in women may not be as effective and innocuous as in patients with a native bladder. Initial treatment with a pubovaginal sling procedure should be considered.  相似文献   
64.
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.  相似文献   
65.
66.
Fibrous dysplasia, in general, appears as an area of markedly increased uptake on bone scintigraphy. Therefore, the possibility of fibrous dysplasia is likely to be excluded when the lesion shows no or slightly increased uptake. The authors report a case of incidentally detected fibrous dysplasia that appeared as slightly increased uptake on bone scintigraphy and was found to harbor a bone infarction along with typical fibrous dysplasia by pathologic examination of a specimen sampled by curettage. Barely increased bone uptake in fibrous dysplasia may be associated with decreased vascularity and osteoblast activity of the lesion as a result of concurrent bone infarction. The authors suggest that not every case of fibrous dysplasia appears as an area of intensely increased uptake on a bone scan. Clinicians should be cautious in interpreting bone scans of radiographically indicated fibrous dysplasia.  相似文献   
67.
Alveolar soft part sarcoma: MR and angiographic findings   总被引:5,自引:5,他引:0  
Suh JS  Cho J  Lee SH  Shin KH  Yang WI  Lee JH  Cho JH  Suh KJ  Lee YJ  Ryu KN 《Skeletal radiology》2000,29(12):680-689
Objective. To present the MR and angiographic findings of alveolar soft part sarcoma (ASPS). Design and patients. MR examinations (12 tumors of 10 patients) of ASPS performed at multiple hospitals were retrospectively reviewed. The tumors were found in the thigh (n=4), lower leg (n=4), femur (n=2, local metastasis), scalp (n=1) and arm (n=1). The MR signal characteristics including signal intensity, homogeneity and signal void of lesions and bony invasion including direct invasion or local metastasis were evaluated. Angiographic findings (n=4) and post-embolotherapy follow-up MR imaging (n=2) findings were also assessed. Results. Local bony metastasis was found in two cases. Seven tumors showed heterogeneous high signal intensity on T1- and T2-weighted images with good enhancement. One tumor had a very high signal on T1-weighted images. Eight tumors (67%) showed numerous signal voids in or near the tumors. All four angiographic studies showed numerous enlarged vessels, arteriovenous shunts and delayed washout. Two cases mimicked arteriovenous malformations on angiographic studies but MR images demonstrated solid soft tissue components as well as tortuous vessels. Conclusions. High signal on T1-weighted image and numerous signal voids are highly suggestive of ASPS, although they are not universal as has been suggested and arteriovenous malformation should be included in the differential diagnosis. Local bony metastases in ASPS were seen in two cases and should be carefully investigated. Received: 12 April 2000 Revision requested: 27 June 2000, 8 August 2000 Revision received: 2 August 2000, 21 August 2000 Accepted: 22 August 2000  相似文献   
68.
ABSTRACT: INTRODUCTION: Although pneumonia has been identified as the single most common risk factor for acute lung injury (ALI), we have a limited knowledge as to why ALI develops in some patients with pneumonia and not in others. The objective of this study was to determine frequency, risk factors, and outcome of ALI in patients with infectious pneumonia. METHODS: A retrospective cohort study of adult patients with microbiologically positive pneumonia, hospitalized at two Mayo Clinic Rochester hospitals between January 1, 2005, and December 31, 2007. In a subsequent nested case-control analysis, we evaluated the differences in prehospital and intrahospital exposures between patients with and without ALI/acute respiratory distress syndrome (ARDS) matched by specific pathogen, isolation site, gender, and closest age in a 1:1 manner. RESULTS: The study included 596 patients; 365 (61.2%) were men. The median age was 65 (IQR, 53 to 75) years. In total, 171 patients (28.7%) were diagnosed with ALI. The occurrence of ALI was less frequent in bacterial (n = 99 of 412, 24%) compared with viral (n = 19 of 55, 35%), fungal (n = 39 of 95, 41%), and mixed isolates pneumonias (n = 14 of 34, 41%; P = 0.002). After adjusting for baseline severity of illness and comorbidities, patients in whom ALI developed had a markedly increased risk of hospital death (ORadj 9.7; 95% CI, 6.0 to 15.9). In a nested case-control study, presence of shock (OR, 8.9; 95% CI, 2.8 to 45.9), inappropriate initial antimicrobial treatment (OR, 3.2; 95% CI, 1.3 to 8.5), and transfusions (OR, 4.8; 95% CI, 1.5 to 19.6) independently predicted ALI development. CONCLUSIONS: The development of ALI among patients hospitalized with infectious pneumonia varied among pulmonary pathogens and was associated with increased mortality. Inappropriate initial antimicrobial treatment and transfusion predict the development of ALI independent of pathogen.  相似文献   
69.
Metastasis is a major cause of cancer recurrence or death. This study attempted to quantitatively identify different proteins in metastatic lung adenocarcinoma. The N/T quotient [number of metastatic lymph nodes (n)/tumor diameter (cm)] was used to select samples with an extreme metastatic phenotype. Among the six fresh frozen lung adenocarcinoma specimens, the three showing the highest N/T quotient represented the metastatic group, and others with the greatest tumor diameters without metastasis represented the non-metastatic group. After 2-dimensional electrophoresis, the significantly different protein spots were selected by image analysis and analyzed with MALDI-TOF mass spectrometry. Acyl-CoA thioesterase 8 isoform c (ACOT8) was one of most overexpressed proteins in the metastatic group, and it was validated by Western blot and immunohistochemical staining on 108 paraffin-embedded tumor samples. High ACOT8 expression was correlated with lymph node metastasis (p = 0.002), recurrence (p = 0.034), predominant histologic subtypes (p = 0.007), and higher stage (p = 0.005). In multivariate analysis, high ACOT8 expression was significantly associated with increased risks of lymph node metastasis (p = 0.009) and cancer-related death (p = 0.030), independent of clinical factors. ACOT8 may be a candidate prognostic biomarker and therapeutic target of lung adenocarcinoma.  相似文献   
70.
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