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排序方式: 共有1112条查询结果,搜索用时 15 毫秒
61.
Kraiem S Chehaibi N Bouladi W Longo S Mghaieth F Bouraoui L Slimane ML 《La Tunisie médicale》2002,80(12):801-806
The aim of this study is to evaluate new echocardiographic modes in diagnosis of arrhythmogenic right ventricular dysplasia (ARVD). Our study is prospective, including ten patients with ARVD and a control group of ten healthy subjects. Transthoracic echocardiography included evaluation of classical criteria's, cross sectional measurements of the right ventricular. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral and septal positions. Assessed by M mode, the total amplitude of the tricuspid annular motion was decreased in the lateral and septal positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (Ea) velocity and an accompanying decrease in early (Ea) to late diastolic(Aa) velocity ratio in all positions; the systolic annular velocity was decreased only in the lateral position. Tricuspid annular measurement are valuable, easy to obtain and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non specific sign of disease. 相似文献
62.
Zefirova JT Zefirova TP Ziganshina LE Ziganshin AU 《Autonomic neuroscience : basic & clinical》2002,99(1):58-61
The contractile activity of the isolated myometrium of pregnant women with mycoplasma, chlamydia and mixed infections has been studied by pharmacological organ bath method. We found that mycoplasma infection decreased while chlamydia or mixed infection increased myometrium contraction evoked by oxytocin or prostaglandin F2alpha. The results of this study could be important for the prediction of possible complications during pregnancy and labour in women with chronic specific urogenital infections. 相似文献
63.
Ictal pattern of EEG and muscular activation in symptomatic infantile spasms: a videopolygraphic and computer analysis 总被引:1,自引:1,他引:0
Bisulli F Volpi L Meletti S Rubboli G Franzoni E Moscano M d'Orsi G Tassinari CA 《Epilepsia》2002,43(12):1559-1563
PURPOSE: To investigate ictal muscular phenomena characterizing symptomatic infantile spasms (ISs) and their relation to ictal EEG. METHODS: Four children with severe encephalopathy, neurologic impairment, and refractory ISs related to different dysplastic lesions, underwent videopolygraphic recordings collecting surface electromyogram (EMG) activity from several cranial and limb muscles to evaluate the pattern of muscular recruitment, duration, and side-to-side asymmetry of ISs. Acquired data were stored for off-line analysis by a computerized polygraphic system. RESULTS: Spasms were characterized by a complex pattern of muscular activation. A constant or rostrocaudal propagation pattern was lacking in all patients. Intervals between the onset of EMG activity in different muscles in each spasm were very long: =100-200 ms. Two patients, with hemispheric cortical dysplasia and agenesis of the corpus callosum, had asymmetric and asynchronous spasms in which the EMG onset of the muscles contralateral to the affected hemisphere constantly anticipated that of the ipsilateral ones. Backaveraging of EEG activity disclosed a high-amplitude EEG complex on the same side as the dysplastic lesion, preceding or succeeding the contralateral muscle activity onset. In the other two patients with diffuse cortical dysplasia, no EEG transient was related to EMG activity onset. CONCLUSIONS: Despite clinical similarity between spasms in the same patient, our data demonstrate the complexity and heterogeneity of these motor phenomena. Our findings cannot be explained simply in terms of cortical or reticular generators like other motor phenomena such as cortical myoclonus or startle reflex. 相似文献
64.
Zaidi M Sifuentes-Osornio J Rolón AL Vázquez G Rosado R Sánchez M Calva JJ de León-Rosales SP 《Archives of medical research》2002,33(3):290-294
BACKGROUND: The impact of nosocomial infections and multidrug resistance on mortality is a topic of considerable controversy. METHODS: A prospective, nested case control study was conducted in four intensive care units (ICUs) in Mexico to measure the impact of antibiotic resistance on and identify the main risk factors for mortality in critically ill patients with nosocomial infections. RESULTS: One hundred thirteen patients developed 119 nosocomial infections. Multivariate analysis identified two variables that were significantly and independently associated with mortality: ventilator-associated pneumonia (p = 0.0041, odds ratio [OR] = 7.7) and inadequate antibiotic treatment (p <0.0001, OR = 70.5). Although antibiotic resistance in Gram-negative rods was not an independent risk factor for mortality, there was a strong association between antibiotic resistance and inadequate treatment (chi2 for linear trend = 29.3, p <0.00001). For patients with ventilator-associated pneumonia, predicted mortality calculated by APACHE II score was 23% compared to an observed mortality of 71%. CONCLUSIONS: In this study the major risk factors for mortality were inadequate antibiotic treatment and development of ventilator-associated pneumonia. Multidrug resistance significantly increased the probability of receiving inadequate antibiotic treatment. The striking differences between observed and predicted mortality in these four ICUs indicate the need for further research and a reassessment of the current programs for prevention and control of nosocomial infections in Mexico. 相似文献
65.
Association of polymyositis with rheumatoid arthritis 总被引:1,自引:0,他引:1
The association of polymyositis (PM) and rheumatoid arthritis (RA) is described in a 40-year-old female Mexican patient who was studied for a long period of time. The characteristic changes of PM that preceded the onset of RA for 7 years included proximal symmetrical muscle weakness, increased creatine kinase activity, and distinctive electromyography and muscle biopsy results. The occurrence of RA during the final 4 years of the 11-year period was characterized by long-lasting deforming and symmetric polyarthritis, high positive rheumatoid factor, subcutaneous nodules, and erosive joint changes. Through observation, myopathic changes other than those from PM were excluded. Joint changes other than from RA were also ruled out. A review of the literature revealed few specific reports of the coexistence of both diseases. 相似文献
66.
67.
The purpose of this study is to evaluate the effect of fluid and diet restriction in fasting on biochemical factors of stone formation. Our study concernes 90 patients divided in three groups: healthy fasting patient (GI), healthy non fasting patient (G2) and non fasting patient with calcium lithiasis (G3). The promotors (oxalate, calcium, uric acid, phosphates) and inhibitors (citrate, magnesium) are statistically significant between G1, G2 and G3, G2. Supersaturation of urine with oxalate, uric acid and brushite are the same for (G1) and (G3) and higher than (G2). Crystalluria is more important in lithiasis subjects compared with healthy non fasting patients (58% vs 11,4%). Oxalate monohydrate (Whewellite) and uric crystal don't exist in the healthy non fasting people but reached 4% and 12% respectively in the lithiasis patient. The crystalluria profil is the same in the heathy fasting patients and calcium lithiasis patients. However healthy patients have equilibria between promotors and inhibitors of crystal formation which minimize the risk of crystalluria and subsequent stone formation. 相似文献
68.
Abdelmoula LC Chaabouni L Ben Hadj Yahia C Montacer Kchir M Zouari R 《Joint, bone, spine : revue du rhumatisme》2005,72(5):427-429
Trochanteric tuberculosis represents less than 2% of all musculo-skeletal tuberculosis. The diagnosis is difficult especially if abscess and fistula are missing. The authors report 3 cases of trochanteric tuberculosis. The diagnosis was established, respectively, 4, 9 months and 1 year after the beginning of the symptoms. The tuberculosis was plurifocal in all cases. Diagnosis was based on the presence of caseum granuloma in the first case, positive Lowenstein culture in the second case and on clinical and paraclinical arguments in the third one. Healing was obtained after medical treatment alone. The authors discuss the potential role of the newer imaging modalities in diagnosis of trochanteric tuberculosis and the indications of medical and surgical treatment. 相似文献
69.
DDT-induced oxidative damage in human blood mononuclear cells 总被引:3,自引:0,他引:3
Pérez-Maldonado IN Herrera C Batres LE González-Amaro R Díaz-Barriga F Yáñez L 《Environmental research》2005,98(2):177-184
Recent work indicates that DDT and its metabolites induce apoptosis in different cellular types. However, the mechanism by which DDT generates apoptosis has not been elucidated. In this study, our data demonstrate that the apoptosis induction by DDT and its metabolites in human peripheral blood mononuclear cells (PBMC) is preceded by an increase in the levels of reactive oxygen species (ROS). Cells isolated from healthy individuals were incubated for different intervals of time (0-24 h) and in the presence of increasing concentrations of p'p-DDT, p'p-DDE, or p'p-DDD (0-80 microg/ml). The induction of oxidative stress was then determined by flow cytometry, using the compound 2',7'-dichlorofluorescein diacetate. The control level of ROS was 4.46+/-0.96 IFM, for DDT- and DDD-treated cells we obtained a 19.0-fold increment, whereas for DDE, the increment was 25-fold. ROS induction by DDT and DDE was observed after 1 h of incubation, while for DDD such levels began to be detected at 3 h of incubation; a maximum effect on the ROS production for the three compounds was found at 6 h of treatment. A significant level of ROS was induced by DDT, DDE, and DDD only at 60 and 80 microg/ml. Finally, to find an association between generation of ROS and apoptosis induction, cells incubated with DDT, DDE, and DDD were evaluated for apoptosis induction and generation of oxidative stress. Our results show that an increase in ROS was accompanied by apoptosis of PBMC in vitro. Moreover, N-acetyl-L-cysteine significantly inhibits the apoptosis induction. 相似文献
70.
Rodríguez-Morales S Compadre RL Castillo R Breen PJ Compadre CM 《European journal of medicinal chemistry》2005,40(9):840-849
Cetylpyridinium chloride (CPC), an alkylpyridinium compound has been recently approved by the US Food and Drug Administration to reduce bacterial contamination in poultry. Although CPC is very effective and has a very good safety record, its relatively high lipophilicity may limit its use in high fat containing foods such as beef. In this study we present the CoMFA analysis (3D-QSAR) of the antimicrobial activity of 60 N-alkylpyridinium compounds against different bacteria. CoMFA contours showed that the activity is highly influenced by the steric factor. Based in these contours we designed new candidates, which were synthesized and characterized by spectroscopic data. MIC activity over Gram positive and Gram negative microorganisms validated the 3D-QSAR study. 相似文献