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101.
Morales MA Ferdeghini EM Piacenti M Dattolo P Distante A Maggiore Q 《Echocardiography (Mount Kisco, N.Y.)》2000,17(3):201-208
Histological changes of the myocardium occur with aging due to an increase in collagen content, hypertrophy of fibers, and patchy fibrosis. Quantitative analysis of conventional echocardiographic images provides an in vivo assessment of myocardial structure by the evaluation of the gray level distribution; with this technique, a relation between myocardial fibrosis and pathological ultrasonic response has been documented. The aim of this study was to evaluate the relation between ultrasonically assessed myocardial structure and age in a normal population. Seventy-eight subjects (47 men; mean age, 51 years; age range, 23-87 years) without apparent cardiovascular and systemic disease underwent conventional two-dimensional echocardiographic examinations. Still frames at end-diastole from apical four-chamber view were digitized and converted in matrices of 256 x 256 pixels. First-order statistical analysis was performed to describe a region of interest in the interventricular septum. The following parameters were studied: mean (gray level amplitude), standard deviation (overall contrast), uniformity (tonal organization), and entropy (tendency of gray levels to be spread). Myocardial structure was assessed in 75 of 78 subjects, divided into three groups: I, age 23-40 years; II, age 41-65 years; and III, > 65 years. Significant differences for all the parameters were found between the age groups. Age correlated directly with mean and entropy (r = 0.77 and 0.69, respectively) and inversely with uniformity (r = 0.70). Our results suggest that quantitative echocardiography can reveal age-related changes in myocardial structure that are characterized by a greater echogenicity and loss in tonal organization, possibly due to increased collagen content within the fibers. 相似文献
102.
103.
G Maggiore C de Giacomo M D Marzani A Colombo M S Scotta 《Archives fran?aises de pédiatrie》1985,42(8):683-685
In order to evaluate the intrafamilial spread of hepatitis B virus (HBV) infection we studied the serological markers of HBV in 101 relatives of 35 children with chronic hepatitis B. Sixty per cent of relatives had markers of infection and 25% showed persistent HBs antigenemia. The high prevalence of HBeAg versus anti-HBe in chronically infected relatives suggests a close temporal relationship of the infection between adults and children. These results support the hypothesis that the child is the main carrier of HBV infection in his family. 相似文献
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105.
Dios Castro E Maquet Dusart JA 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(11):775-778
PURPOSE/METHOD: We present a case of a patient who developed recurrent epithelial herpes simplex keratitis after starting treatment with latanoprost. Her ophthalmic history was only remarkable for a past episode of herpetic keratitis 21 years previously. RESULTS/CONCLUSIONS: Episodes of herpetic keratitis were under remission only when latanoprost was discontinued. No recurrences of herpes simplex keratitis have been observed since then. Latanoprost usage might be associated with recurrent episodes of herpes simplex keratitis in patients with previous history of ocular herpes simplex virus infection. 相似文献
106.
Monge-Argiles J Maloteaux J Van Den Bergh P Sindic C 《Neurología (Barcelona, Spain)》2002,17(2):110-112
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis. 相似文献
107.
山苍子水提物柠檬醛抗哮喘作用的实验研究 总被引:5,自引:0,他引:5
目的:研究山苍子水提物柠檬醛的抗哮喘作用及其机理。方法:通过豚鼠氯化乙酰胆碱-磷酸组胺喷雾致喘法、小鼠浓氨水喷雾引咳法、小鼠酚红排泻法观察柠檬醛的平喘、镇咳、祛痰作用,通过观察张力变化研究柠檬醛对豚鼠离体气管环张力的影响及乙酰胆碱对气管收缩的抑制作用。结果:柠檬醛能明显延长氯化乙酰胆碱-磷酸组胺喷雾引起的豚鼠哮喘潜伏期,能延长浓氨水喷雾诱发小鼠咳嗽反应潜伏期,明显减少咳嗽次数。能增加小鼠呼吸道酚红排泌量,能抑制乙酰胆碱对豚鼠离体气管平滑肌的收缩作用,使乙酰胆碱所致气管平滑肌量效曲线右移。结论:柠檬醛气雾剂具有一定的平喘、镇咳和祛痰作用,具有良好的支气管解痉作用。 相似文献
108.
Michael H Holzscheiter Niels Bassler Nzhde Agazaryan Gerd Beyer Ewart Blackmore John J DeMarco Michael Doser Ralph E Durand Oliver Hartley Keisuke S Iwamoto Helge V Knudsen Rolf Landua Carl Maggiore William H McBride S?ren Pape M?ller J?rgen Petersen Lloyd D Skarsgard James B Smathers Timothy D Solberg Ulrik I Uggerh?j Sanja Vranjes H Rodney Withers Michelle Wong Bradly G Wouters 《Radiotherapy and oncology》2006,81(3):233-242
BACKGROUND AND PURPOSE: Antiprotons travel through tissue in a manner similar to that for protons until they reach the end of their range where they annihilate and deposit additional energy. This makes them potentially interesting for radiotherapy. The aim of this study was to conduct the first ever measurements of the biological effectiveness of antiprotons. MATERIALS AND METHODS: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7MeV antiprotons, 48MeV protons, or (60)Co gamma-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose and particle fluence response relationships were constructed from data in the plateau and Bragg peak regions of the beams and used to assess the biological effectiveness. RESULTS: Due to uncertainties in antiproton dosimetry we defined a new term, called the biologically effective dose ratio (BEDR), which compares the response in a minimally spread out Bragg peak (SOBP) to that in the plateau as a function of particle fluence. This value was approximately 3.75 times larger for antiprotons than for protons. This increase arises due to the increased dose deposited in the Bragg peak by annihilation and because this dose has a higher relative biological effectiveness (RBE). CONCLUSION: We have produced the first measurements of the biological consequences of antiproton irradiation. These data substantiate theoretical predictions of the biological effects of antiproton annihilation within the Bragg peak, and suggest antiprotons warrant further investigation. 相似文献
109.
110.
PURPOSE: We assess the reliability of intraoperative cavernous nerve stimulation for producing an erectile response during radical prostatectomy. MATERIALS AND METHODS: In 61 patients cavernous nerve function was assessed during radical retropubic prostatectomy using a CaverMap nerve stimulator. Control stimulation was also performed before and after prostatic dissection by placing the nerve stimulator tip on the anterior bladder wall. An increase in penile circumference measured by the device was considered a tumescence response while any measurable detumescence was also categorized. RESULTS: Patient age ranged 43 to 72 years (mean 59.8). Before apical dissection 41% and 46% had tumescence, 31% and 21% had detumescence, and 28% and 33% had no response with stimulation of the neurovascular bundle and anterior bladder wall, respectively. After dissection 42% and 25% had tumescence, 16% and 18% had detumescence, and 42% and 57% had no response with stimulation of the neurovascular bundle and anterior bladder wall, respectively. CONCLUSIONS: A response to neurovascular bundle stimulation using this device does not necessarily correlate with the precise anatomical location of the cavernous nerves. There is considerable background variability related to anesthesia, surgical manipulation and other undefined factors that may cause minor but measurable changes in penile circumference. 相似文献