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1.
Objective The degree of Left Ventricular Mass Index (LVMI) regression following aortic valve replacement correlates with long-term survival. This study aims to assess the extent of LVMI regression at 3 months following aortic valve replacement (AVR) with different types and sizes of mechanical valves in rheumatic aortic valve disease. Methods The LVMI regression was studied in 34 consecutive patients, undergoing elective AVR for rheumatic aortic stenosis and/or regurgitation. They were grouped in A and B, matched in age, body surface area and pre-operative LVMI, receiving respectively a tilting disc and a bileaflet mechanical valve. The LVMI was calculated by M-mode echocardiography using the Devereux' formula pre-operatively and three months post-operatively. The trend of LVMI reduction was compared between the two groups and amongst the patients with stenotic, regurgitant and mixed aortic valve, pathologies; and receiving different sizes of valves. Results The mean preoperative LVMI was 199g±79.5 g/m2. At three months post aortic valve replacement, the mean LVMI was 130g±49.0 g/m2. There was a significant reduction of LVMI post-operatively (p=0.001) at three months follow-up. The extent of LVMI regression following surgery amongst the groups A and B did not vary significantly (p=0.92). The extent of LVMI regression did not vary significantly in patients with different aortic valve pathology nor with different sizes of the valves implanted. Conclusions There is a significant early LVMI regression following aortic valve replacement in rheumatic aortic valve disease. The type and the size of the mechanical prosthesis or the rheumatic pathology do not appear to influence this regression.  相似文献   
2.
Serum copper and iron in ischemic heart disease   总被引:1,自引:0,他引:1  
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3.
Tetrahydrocortisol, -cyclodextrin tetradecasulfate, and minocycline used alone or in combination are not very cytotoxic toward EMT-6 mouse mammary tumor cells growing in monolayer. Tetrahydrocortisol (100 M, 24 h) and -cyclodextrin tetradecasulfate (100 M, 24 h) protected EMT-6 cells from the cytotoxicity of CDDP, melphalan, 4-hydroperoxycyclophosphamide, BCNU, and X-rays under various conditions of oxygenation and pH. Minocycline (100 M, 24 h) either had no effect upon or was additive with the antitumor alkylating agents or X-rays in cytotoxic activity toward the EMT-6 cells in culture. The combination of the three modulators either had no effect upon or was to a small degree protective against the cytotoxicity of the antitumor alkylating agents or X-rays. The Lewis lung carcinoma was chosen for primary tumor growth-delay studies and tumor lung-metastases studies. Tetrahydrocortisol and -cyclodextrin tetradecasulfate were given in a 1:1 molar ratio by continuous infusion over 14 days, and minocycline was given i.p. over 14 days, from day 4 to day 18 post tumor implantation. The combination of tetrahydrocortisol/-cyclodextrin tetradecasulfate diminished the tumor growth delay induced by CDDP and melphalan and produced modest increases in the tumor growth delay produced by cyclophosphamide and radiation. Minocycline co-treatment increased the tumor growth delay produced by CDDP, melphalan, radiation, bleomycin, and, especially cyclophosphamide, where 4 of 12 animals receiving minocycline (14×5mg/kg, days 4–18) and cyclophosphamide (3×150 mg/kg, days, 7, 9, 11) were long-term survivors. The 3 modulators given in combination produced further increases in tumor growth delay with all of the cytotoxic therapies, and 5 of 12 of the animals treated with the 3-modulator combination and cyclophosphamide were long-term survivors. Although neither tetrahydrocortisol/-cyclodextrin tetradecasulfate, minocycline, nor the three modulator combination impacted the number of lung metastases, there was a decrease in the number of large lung metastases. Treatment with the cytotoxic therapies alone reduced the number of lung metastases. Addition of the modulators to treatment with the cytotoxic therapies resulted in a further reduction in the number of lung metastases. These results indicate that agents that inhibit the breakdown of the extracellular matrix can be useful additions to the treatment of solid tumors.Abbreviations 14(SO4)ßCD -cyclodextrin tetradecasulfate - THC tetrahydrocortisol - CDDP cis-diamminedichloroplatinum(II) - 4-HC 4-hydroperoxycyclophosphamide - BCNU N,N-bis(2-chloroethyl)-N-nitrosourea - CAM chick embryo chorioallantoic membrane; IC50, concentration of a drug required to kill 50% of the cells This work was supported by NIH grant P01-CA38493 and a grant from Bristol-Myers-Squibb, Inc., Wallingford, Connecticut  相似文献   
4.
Hypothesis: Analysis of salivary gland lesions by FNAC and correlation with histopathology. To evaluate utility of FNAC in salivary gland lesions.Back ground: Salivary gland lesions form about 2–6.5% of all head and neck neoplasms in adults. They are easily accessible for FNAC (Fine Needle Aspiration Cytology) and risks of fistula formation or tumour implantation are low compared surgical biopsy. Also, cytology can provide a distinction between asalivary and non salivary lesion, benign and malignant lesions so also specific and non specific inflammation. Methods: Seventy patients were studied prospectively over two years. FNAC was done using 10 cc syringes and 20–22 no. needle. Histomorphology was assessed on routine H & E (haemotxylin and eosin) stained paraffin sections. SPAS (periodic acid Schiff) and mucicarmine satins were also done. Results: 80% of the lesions were neoplastic (61% benign, 31% malignant) and 20% were neoplastic. Pleomorphic adenoma was the most frequent benign neoplasm while mucoepidermoid carcinoma was the most frequent malignant lesion. Among the non neoplastic lesions, the maximum number of cases were of chronic sialadentis. In the present study, FNAC has a sensitivity of 94.54% and specificity of 80.95% for neoplastic lesions. Conclusions: FNAC was found to be a useful diagnostic tool in the evaluation of salivary gland lesions because of its simplicity, excellent patient compliance and rapid diagnosis. This cost effective tool is invaluable in planning the surgical management of the patient.  相似文献   
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6.
Purpose:To estimate the prevalence of blindness and severe visual impairment (SVI) by using a door-to-door screening and vision center (VC) examination strategy in an urban area in western Maharashtra (Pune), India and repeat the exercise after 4 years to study its impact.Methods:Four trained community health workers measured the visual acuity and performed an external ocular examination in patients’ homes. People with vision <6/18 were requested to visit the VC for a comprehensive eye examination by an optometrist. An ophthalmologist examined people whose vision did not improve to 6/12. A home examination was done for people who did not visit the VC despite two requests. The same population was examined twice in an interval of 4 years.Results:In the study, 44,535 people in 2015–16 and 98.14% (n = 43,708) of them in 2018–19 were examined. Blindness (vision < 3/60 in better eye), and moderate-to-severe visual impairment (MSVI, vision 6/18–6/60 in better eye) were 0.26% and 1.3%, respectively, in the first cohort, and 0.16% and 1.1%, respectively, in the second cohort (P < 0.001). When the worse eye was considered, the prevalence of blindness reduced from 0.72% to 0.44%, SVI reduced from 0.1% to 0.07%, and MVI decreased from 1.7% to 1.49% between 2015 and 2019 (P < 0.001). Females (P < 0.001) and older individuals (P < 0.001) were more likely to have blindness or SVI. In the VC, 8211 people were examined in 4 years.Conclusion:The reduction of blindness and MSVI in the urban area of Pune can be partly ascribed to the presence of a VC and attendant screening in this locality.  相似文献   
7.
A community-based nationwide survey for hearing loss was conducted in Oman in 1996–97. Audiometric tests and ear examinations were conducted for 12 400 persons in phase I. For children aged less than 4 years, subjective screening tests were used. In phase II, otologists examined the hearing-impaired subjects to determine the cause. The prevalence of bilateral hearing impairment was 55/1000 (95% CI 51.08–59.47). Gender difference was not significant. The rates were 325/1000 and 17/1000, respectively, in the _60-year and _10-year age groups. Presbyacusis and middle ear diseases, respectively, were the causes of 33% and 20% of bilateral hearing impairment. In 30% of the bilateral hearing-impaired subjects, the cause could not be determined. The prevalence of bilateral disabling hearing loss was 21/1000 (95% CI 18.07–23.29). Noise-induced trauma was responsible for only 1.4% of cases of disabling hearing loss. Establishing primary ear care, introducing hearing screening for neonates and schoolchildren, promoting safe preventive practices for ear care, strengthening secondary-level ear care services and introducing comprehensive rehabilitative initiatives for the hearing-disabled are recommended to reduce the hearing loss rates.  相似文献   
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9.
Purpose: To survey the opinion of oculoplastic surgeons on the assessment and management of lower eyelid retraction (LLR).

Methods: A web-based survey queried oculoplastic surgeon members of Ojoplast, Spanish and Brazilian Oculoplastic Societies on the management of LLR. The frequency and percentage proportions of the responses were analyzed.

Results: One hundred ninety-six oculoplastic surgeons participated in the survey. The main cause of LLR is post-blepharoplasty (62;31.6%). The most used sign to detect LLR is scleral show. The most common approaches to managing LLR are lateral canthal surgery (164/593;27.6%), autogenous spacers (148/593; 24.9%) and retractor release (131/593;22.1%). The preferred autogenous graft material includes ear cartilage (102/260;39.2%). The majority of surgeons (161/314; 51.3%) recommend massage or steroids injection (80/314;25.5%) for early post-blepharoplasty LLR, while, 54.1% (106/196) of participants suggested waiting for at least six months prior to surgical intervention. Frost suture is used after most LLR surgeries (154/196;91.1%). Incomplete correction is the main complication (111/310;35.8%) of LLR surgery. For mild LLR, 48% of the responders prefer clinical treatment; conversely, severe cases routinely require combined surgical techniques.

Conclusions: Oculoplastic surgeons frequently diagnose LLR based on scleral show. LLR management depends on the cause and severity of lid retraction. Mild cases, in general, receive clinical treatment and severe cases need a combination of surgical techniques and grafts.  相似文献   

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