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101.
Angiographic profile of ischaemic stroke in the young--study of 143 cases   总被引:1,自引:0,他引:1  
The incidence of stroke in the young is higher in the Indian subcontinent than in the West, but the precise cause is not known. Previous angiographic studies in cases of "young stroke" have yielded variable results. The present angiographic study of 143 cases of young stroke (under 40 years of age) showed a high incidence of abnormality (71%). The lesions included atherosclerotic disease of the internal carotid artery (68%), stenosis/occlusion of the major intracranial vessels (37%) and small-vessel disease. Tandem lesions were common (26%). Primary atherosclerosis is thought to be the cause of young stroke in the Indian population.  相似文献   
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Favipiravir,an antiviral, was given restricted emergency use approval to treat coronavirus disease 2019 (COVID-19) in many countries. While the clinical efficac...  相似文献   
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Ehrlichioses are emerging tick-borne bacterial diseases of humans and animals for which no vaccines are available. The diseases are caused by obligately intracellular bacteria belonging to the genus Ehrlichia. Several immunoreactive proteins of ehrlichiae have been identified based on their reactivity with immune sera from human patients and animals. These include the major outer membrane proteins, ankyrin repeat proteins and tandem repeat proteins (TRP). Polyclonal antibodies directed against the tandem repeats (TRs) of Ehrlichia chaffeensis TRP32, TRP47 and TRP120 have been shown to provide protection in mice. In the present study, we evaluated E. muris P29, which is the ortholog of E. chaffeensis TRP47 and E. canis TRP36, as a subunit vaccine in a mouse model of ehrlichiosis. Our study indicated that unlike E. chaffeensis TRP47 and E. canis TRP36, orthologs of E. muris (P29) and E. muris-like agent (EMLA) do not contain tandem repeats. Immunization of mice with recombinant E. muris P29 induced significant protection against a challenge infection. The protection induced by E. muris P29 was associated with induction of strong antibody responses. In contrast to development of P29-specific IgG antibodies following immunization, development of P29-specific IgG antibodies, but not IgM antibodies, was impaired during persistent E. muris infection. Furthermore, our study indicated that CD4+ T cells target P29 during E. muris infection and differentiate into IFN-γ-producing Th1 effector/memory cells. In conclusion, our study indicated that orthologs of E. muris P29 showed considerable variation in the central tandem repeat region among different species, induction of P29-specific IgG antibody response was impaired during persistent E. muris infection, and rP29 induced protective immune responses.  相似文献   
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Endolymphatic mastoid shunt: a reevaluation of efficacy.   总被引:1,自引:0,他引:1  
OBJECTIVES: The main goal of this paper was to statistically reevaluate the efficacy of the endolymphatic shunt procedure for Meniere's disease. METHODS: Thomsen et al (Arch Otolaryngol 1981;107:271-7) reported on the placebo effect in surgery for Meniere's disease in a controlled double-blind study. Thirty patients with typical Meniere's disease in whom medical treatment failed participated in the study. A placebo-controlled blinded surgical study has not since been replicated. We performed a retrospective statistical analysis using data extracted from the published report and reanalyzed it using both the original and new statistical measures and techniques. RESULTS: The original conclusions drawn by Thomsen et al differed considerably from ours in 5 key areas, including postoperative vertigo, nausea and vomiting, tinnitus, and combined score. CONCLUSIONS: This analysis strongly supports the effectiveness of the endolymphatic shunt in the management of Meniere's disease and refutes the placebo effect previously proposed.  相似文献   
109.
The microdosing strategy allows for early assessment of human pharmacokinetics of new chemical entities using more limited safety assessment requirements than those requisite for a conventional phase I program. The current choice for evaluating microdosing is accelerator mass spectrometry (AMS) due to its ultrasensitivity for detecting radiotracers. However, the AMS technique is still expensive to be used routinely and requires the preparation of radiolabeled compounds. This report describes a feasibility study with conventional liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology for oral microdosing assessment in rats, a commonly used preclinical species. The nonlabeled drugs fluconazole and tolbutamide were studied because of their similar pharmacokinetics characteristics in rats and humans. We demonstrate that pharmacokinetics can be readily characterized by LC-MS/MS at a microdose of 1 microg/kg for these molecules in rats, and, hence, LC-MS/MS should be adequate in human microdosing studies. The studies also exhibit linearity in exposure between the microdose and >or=1000-fold higher doses in rats for these drugs, which are known to show a linear dose-exposure relationship in the clinic, further substantiating the potential utility of LC-MS/MS in defining pharmacokinetics from the microdose of drugs. These data should increase confidence in the use of LC-MS/MS in microdose pharmacokinetics studies of new chemical entities in humans. Application of this approach is also described for an investigational compound, MLNX, in which the pharmacokinetics in rats were determined to be nonlinear, suggesting that MLNX pharmacokinetics at microdoses in humans also might not reflect those at the therapeutic doses. These preclinical studies demonstrate the potential applicability of using traditional LC-MS/MS for microdose pharmacokinetic assessment in humans.  相似文献   
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