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31.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
32.
Nystagmus signaling vestibular dysfunction was observed after vibratory stimulation with a 100 Hz ABC stimulator in a population of 36 patients with unilateral labyrinthine pathology (ULP) (pre and postoperative neuromas, vestibular neurectomies) and 10 patients with vestibular neuritis. The stimulus was applied on 3 bony points of the skull (vertex and 2 mastoids) and 2 muscular points of the neck (right and left posterior cervical region). These results were compared with those in 95 normal subjects and 19 cases of central disease and were correlated on the same day with results of the caloric test and head shaking test (HST). A consistent nystagmus was found in only 6 % of the normal subjects (specificity 94 %) and in 10 % of the central lesions, but in 94 % of the 36 peripheral ULP. The sensitivity of the test was equivalent to the HST. The signal was optimized in 30 patients: stimulus frequency, amplitude, stimulator mass, form of the contact, patient tolerance. The best results were obtained for a frequency of 100 Hz and an amplitude of 0.5 mm (there was no response under 0.1 mm vibration amplitude). Under videoscopy and 3D videonystagmography, the direction or side of the nystagmus was constant, but its axis (horizontal, oblique or rotational) changed according to the location of the stimulator: on the mastoid (elective location of stimulation with responses in 94 % of cases) the axis was most often horizontal or horizontal rotational. On the vertex location (where nystagmus was observed in 60 % of cases) the axis of nystagmus was most often rotational or oblique and sometimes horizontal-rotational. The nystagmus showed short latency (less than 200 ms). It started and stopped as stimulation was initiated and interrupted. Nystagmus persisted for the duration of patient tolerance. This nystagmus generally signifies unilateral vestibular weakness rather than vestibular predominance. It is a good indicator of unilateral vestibular dysfunction and could serve as a useful test in clinical practice. We discuss the origin of the nystagmus which may originate in muscle proprioception (by propagation of the vibration to neck muscles) or in the labyrinth (simultaneous excitation of 3 canals on each side).  相似文献   
33.
Recently the two vesicular-glutamate-transporters VGLUT1 and VGLUT2 have been cloned and characterized. VGLUT1 and VGLUT2 together label all glutamatergic neurons, but because of their distinct expression patterns in the brain they facilitate our ability to define between a VGLUT1-positive cortical and a VGLUT2-positive subcortical glutamatergic systems. We have previously demonstrated an increased cortical VGLUT1 expression as marker of antidepressant activity. Here, we assessed the effects of different psychotropic drugs on brain VGLUT2 mRNA and protein expression. The typical antipsychotic haloperidol, and the atypicals clozapine and risperidone increased VGLUT2 mRNA selectively in the central medial/medial parafascicular, paraventricular and intermediodorsal thalamic nuclei; VGLUT2 protein was accordingly amplified in paraventricular and ventral striatum and in prefrontal cortex. The antidepressants fluoxetine and desipramine and the sedative anxiolytic diazepam had no effect. These results highlight the implication of thalamo-limbic glutamatergic pathways in the action of antipsychotics. Increased VGLUT2 expression in these neurons might constitute a marker for antipsychotic activity and subcortical glutamate neurotransmission might be a possible novel target for future generation antipsychotics.  相似文献   
34.
In a context of therapeutic revolution in older adults with AML, it is becoming increasingly important to select patients for the various treatment options by taking account of short-term efficacy and toxicity as well as long-term survival. Here, the data from three European registries for 1,199 AML patients aged 70 years or older treated with intensive chemotherapy were used to develop a prognostic scoring system. The median follow-up was 50.8 months. In the training set of 636 patients, age, performance status, secondary AML, leukocytosis, and cytogenetics, as well as NPM1 mutations (without FLT3-ITD), were all significantly associated with overall survival, albeit not to the same degree. These factors were used to develop a score that predicts long-term overall survival. Three risk-groups were identified: a lower, intermediate and higher-risk score with predicted 5-year overall survival (OS) probabilities of ≥12% (n = 283, 51%; median OS = 18 months), 3–12% (n = 226, 41%; median OS = 9 months) and <3% (n = 47, 8%; median OS = 3 months), respectively. This scoring system was also significantly associated with complete remission, early death and relapse-free survival; performed similarly in the external validation cohort (n = 563) and showed a lower false-positive rate than previously published scores. The European Scoring System ≥70, easy for routine calculation, predicts long-term survival in older AML patients considered for intensive chemotherapy.Subject terms: Acute myeloid leukaemia, Risk factors  相似文献   
35.
目的:比较清开灵与利巴韦林对呼吸道合胞病毒肺炎患儿治疗效果的差异。方法:选择2005-02/2006-04在北京儿童医院分中心治疗的小儿呼吸道合胞病毒肺炎97例,患儿法定监护人知情同意。采用单盲、随机、平行对照试验的原则,按区组随机化方法分为2组,清开灵注射液组49例,利巴韦林组48例。①清开灵注射液组:清开灵注射液静脉滴注加口服中成药。②利巴韦林组:利巴韦林注射液静脉滴注加口服复方愈创木酚磺酸钾口服液。两组疗程均为10d,比较两组患儿的疗效。结果:清开灵注射液组脱落3例,利巴韦林组脱落1例,进入结果分析清开灵注射液组46例,利巴韦林组47例。①清开灵注射液组发热患儿体温恢复正常时间比利巴韦林组短[(2.72±1.86)d,(6.29±2.41)d(P<0.01)]。②清开灵注射液组患儿咳嗽、痰壅、气促症状积分改善方面优于利巴韦林组(P<0.05~0.01)。③清开灵注射液组的呼吸道合胞病毒转阴时间明显优于利巴韦林组。④咳嗽、痰壅、病毒转阴时间、气促均进入Logistic模型,其中前两个症状的回归系数绝对值较大。结论:清开灵注射液治疗小儿呼吸道合胞病毒肺炎在退热、止咳平喘、呼吸道合胞病毒转阴时间等方面均具有明显优势,咳嗽、痰壅这两个症状更能反映清开灵注射液的疗效优于利巴韦林。  相似文献   
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38.
G. Dumas  E. Canet 《Réanimation》2016,25(3):123-136
Survival of cancer patients has dramatically increased with the development of new treatments such as targeted therapies. Nevertheless, physicians now face new challenges as identifying and addressing treatment toxicities. While infection remains the leading cause of intensive care unit (ICU) admissions in these patients, various cardiovascular toxicities may occur during multiple lines of chemotherapy and targeted therapies, with progressively higher cumulative doses. Anthracyclines cardiotoxicity was identified in 1950 and has been extensively reported. More recently, multiple cardiovascular side effects of targeted therapies (monoclonal antibodies and tyrosine kinase inhibitors) have been described, including severe hypertension, cardiac failure, arrhythmia, myocardial ischemia, and pericardial effusion. In addition, the risk of both venous and arterial thromboembolic events is increased with the use of chemotherapy and targeted therapies, which can lead to ICU admission in the severe forms or because of bleeding events related to anticoagulation therapy. Microvascular endothelial cell injuries induced by cancer therapies or immunosuppressive agents may be responsible for thrombotic microangiopathy or posterior reversible encephalopathy syndrome. Finally, acute hypersensitivity reactions to chemotherapy or monoclonal antibodies can cause changes in blood pressure or anaphylactoid shock in the most severe cases. Critically ill cancer patients who experienced chemotherapy-related cardiovascular events require the same therapeutic approach to the cardiopathic patients. Maximal intensive care support is justified as most of these toxicities are potentially reversible.  相似文献   
39.

Background  

Breathlessness causes significant burden in our community but the underlying socio-demographic and lifestyle factors that may influence it are not well quantified. This study aims to define these predictors of chronic breathlessness at a population level.  相似文献   
40.
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