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21.
Supplements of glucosamine hydrochloride, low molecular weight chondroitin sulfate, and manganese ascorbate were tested separately and in combination for their ability to retard progression of cartilage degeneration in a rabbit instability model of osteoarthrosis. Computerized quantitative histologic evaluation of safranin O stained sections of the medial femoral condyles measured the grade and extent of tissue involvement of lesions. Severe lesions (Mankin grade greater than 7) were absent in all animals supplemented with a dietary mixture of glucosamine, chondroitin sulfate, and manganese ascorbate. Total linear involvement (mm of lesioned surface) and total grade (mean grade x number of lesions per animal) were reduced significantly in animals given the combination compared with controls (59% and 74% respectively). Animals supplemented with glucosamine, chondroitin sulfate, or manganese ascorbate alone had less moderate and severe tissue involvement than controls but not to the extent of the combined group. In vitro, a combination of glucosamine hydrochloride and chondroitin sulfate acted synergistically in stimulating glycosaminoglycan synthesis (96.6%). Chondroitin sulfate and manganese ascorbate but not glucosamine were effective in inhibiting degradative enzyme activity. These data suggest that the disease modifying effect (the ability to retard progression of cartilage degeneration) of a mixture of glucosamine, chondroitin sulfate, and manganese ascorbate is more efficacious than either agent alone.  相似文献   
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目的:评估助视器对年龄相关性黄斑变性(AMD)患者视功能恢复和阅读速度的影响。方法:对低视力门诊44名AMD患者进行评估。收集并分析使用助视器前和使用助视器时裸眼视力、最佳矫正视力、屈光状态、助视器类型(LVAs)以及阅读速度的相关数据。结果:共44例AMD患者,平均年龄为73±10.8岁,男性36例(82%)。其中,29例(67%)受试者视力较好的眼远视力(DVA)为1.0~1.6 LogMAR,而36例(82%)受试者近视力(NVA)小于3.2 m。使用助视器时平均DVA提高0.67±0.27 LogMAR(P=0.000)。使用LVAs时,42例患者NVA达到1 m甚至更佳,仅有2例(4.5%)没有使用LVAs的患者NVA为1 m。在使用一定时间的助视器后,有阅读能力的患者平均阅读速度从每分钟2.9±4.78字提高到每分钟71.31±29.96字(P<0.001)。15名受试者远距离视觉使用单目望远镜,而戴高倍单目镜片眼镜作为最常用的阅读辅助工具。结论:LVAs对AMD患者的视功能恢复和阅读能力的提高有一定的作用。对于AMD患者而言,接受低视力护理服务是有必要的。  相似文献   
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For the prevention of postoperative ocular infections prophylactic topical antibiotics are routinely used. Studies evaluating comparative difference between single dose versus multiple dose administration on aqueous humour concentration of moxifloxacin are lacking. This study compared the aqueous humour concentration of moxifloxacin following its topical administration in rabbit eyes with two dose regimens. Twelve albino rabbits were divided into two groups. In group-1, two drops were administered thrice (total six drops) at 2 min intervals, in both the eyes; in group-2, two drops of moxifloxacin were administered three times a day for three days and also two h before aqueous humour collection i.e. on fourth day. Mean aqueous humour concentrations were calculated and compared using Student''s ‘t’ test and P<0.05 was considered significant. Moxifloxacin concentration in aqueous humour in group-1 was 23.79 μg/ml and in group-2 was 42.08 μg/ml. Both dosing regimens produced substantially higher aqueous concentrations than the known minimum inhibitory concentration for most bacteria. Moxifloxacin concentration in aqueous humour with multiple instillations is significantly higher than single instillation (P<0.05), which is adequate to cover ciprofloxacin-resistant gram-negative bacteria. Repeated topical moxifloxacin administration achieved significantly higher aqueous humour concentrations than single administration.  相似文献   
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ABSTRACT

Introduction

Since the developmentof combined antiretroviral therapy (cART), HIV-associated mortality and the incidence of HIV-associated end-stage kidney disease (ESKD) has decreased. However, in the United States, an increase in non-HIV-associated kidney diseases within the HIV-positive population is expected.  相似文献   
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Myocardial infarction (MI) following blunt chest trauma is rare, but potentially fatal. We treated a young patient for acute MI after falling chest-first on ice while playing hockey. Coronary artery bypass grafting (CABG) was performed after percutaneous stenting attempts were unsuccessful. By reviewing the related literature, we found 179 cases, the majority of which affected young males following road accidents. Left anterior descending artery was most frequently affected followed by right coronary artery particularly in their proximal thirds. Prior to the advent of emergent angioplasty for MI, conservative management was frequently pursued, whereas subsequently both stenting and CABG were performed as initial therapy. Several cases required CABG after the failure of stenting attempts. Trauma-associated MI is uncommon but should be suspected to be properly diagnosed and managed; the potential need for CABG requires that a cardiac surgeon be informed at the time of angiography to avoid possible delay in revascularization.  相似文献   
29.
Kommerell’s diverticulum is a rare saccular aneurysmal dilation of the descending aorta. We report a case of a 3.5-year-old boy with the extremely rare combination of Kommerell’s diverticulum with a right descending aorta and proximal patent ductus arteriosus aneurysm forming an incomplete vascular ring. To our knowledge, this rare case has not been reported to date.  相似文献   
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Earlier studies have suggested an important role of glutathione (GSH) in cytoprotection against free radicals induced oxidative damage. This study reports gastroprotective effects of a cysteine precursor, L-2-oxothiazolidine-4-carboxylate (OTC), in experimental models of gastric secretion and ulceration. Acid secretion studies (volume and acidity) were undertaken in pylorus-ligated rats whereas the gastric lesions were induced by ethanol. Different groups of animals were treated with OTC (0, 100, 200 and 400 mg/kg). The levels of gastric wall mucus, nonprotein sulfhydryls (NP-SH) and myeloperoxidase (MPO) were measured in the glandular stomach of rats following ethanol-induced gastric lesions. Both medium and high doses of OTC significantly reduced the volume and acidity of gastric secretion in pylorus-ligated rats. Pretreatment with OTC significantly and dose-dependently attenuated the formation of ethanol-induced gastric lesion. OTC significantly protected the gastric mucosa against ethanol-induced depletion of gastric wall mucus, NP-SH and MPO. The gastroprotective effects of OTC may be attributed to its ability to inhibit neutrophils activity and replenish GSH demand.  相似文献   
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