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291.
Reticulated platelets (RP) are the youngest platelets in the circulation and can be measured by analysing the RNA content of platelets from whole blood or platelet-rich plasma by flow cytometry. Increased RP are indicative of increased production of platelets. Despite the current lack of standardization for the measurement of RP, it is useful in the assessment of patients with ITP by aiding the distinction of these patients from those with decreased platelet production. RP counts also have a role in the assessment of the complicated patient with multiple possible aetiologies for thrombocytopenia. Measurement of the RP count may hold predictive value for marrow recovery following myelosuppressive or myeloablative chemotherapy, and may play a role in monitoring the administration of the various thrombopoietins currently under clinical trial.  相似文献   
292.
Immune thrombocytopenic purpura (ITP) is a disorder for which management remains controversial. The ongoing goal is to define the minimal therapy required for children with acute ITP. A pilot study of short-course oral prednisone (4 mg−1 kg−1 d−1 for 4 d with no tapering) was undertaken in 25 consecutive children with acute ITP and platelet counts under 20 × 109 1−1. Of the 25 children, 22 responded to the prednisone therapy by achieving a platelet count higher than 20 × 109 1−1 within 1 week of commencing treatment. This regimen was found to be safe, inexpensive and effective in increasing the platelet count of children to a haemostatically safe level.  相似文献   
293.
The management of acute and chronic immune thrombocytopenic purpura (ITP) of children differs in many aspects from that of adults. Current paediatric and adult treatment options are discussed in this review in the light of the recently published practice guidelines for the diagnosis and treatment of ITP issued by a panel of paediatric and adult haematologists on behalf of the American Society of Hematology. Uncontrolled rather than controlled randomized studies often represent the basis for treatment decisions. Important issues in improving the management of patients with ITP include the identification of research priorities resulting in controlled clinical trials with well-defined study endpoints, the logistics and coordination of research activities and their presentation at international meetings.  相似文献   
294.
All attendees participated in a round-table discussion regarding directions for research in autoimmune thrombocytopenic purpura (ITP). Suggested areas for study were grouped into five main areas: (i) improved classification of ITP identifying subsets of patients with differing clinical syndromes and response to treatment, and those more likely to have serious bleeding manifestations; identification of patients with reduced thrombopoiesis was emphasized; (ii) studies aimed at elucidating the aetiology and pathophysiology of ITP, with emphasis on distinctions between acute and chronic ITP and between patients responsive or refractory to therapy; these studies focused on measures of humoral and cellular immune dysregulation; (iii) studies of platelet function in ITP, with the intent of defining these abnormalities and correlating them with the clinical manifestations of the disease; (iv) new approaches to treatment, particularly of refractory patients; and (v) a miscellaneous group, which included development of an ITP registry, evaluation of the "burden" of disease, investigation of mood changes in ITP, etc. The discussion was not intended to be all-inclusive, but focused on the content of other talks in this symposium. It is hoped that some of thesesuggestions will be further developed for investigation in multicentre co-operative studies to improve the diagnosis, understanding and treatment of ITP.  相似文献   
295.
The early postdenervation depolarization of rat diaphragm muscle fibers (8–10 mV within 3 h in vitro) is substantially smaller (3 mV) when muscles are bathed with 1×10?3 M l-glutamate (Glu) or 1×10?3 M N-methyl-d-aspartate (NMDA). The effects of Glu and NMDA are inhibited in a dose-dependent manner by competitive inhibitor 2-amino-5-phosphonovaleric acid (APV) withK i 6.3×10?4 M, by 2×10?7 M MK-801, which acts as an open channel inhibitor, by 2–3×10?4 Zn2+, which reacts with surface-located sites of the NMDA subtype of the glutamate receptor, and also by glycine-free solutions and 7-Cl-kynurenic acid, which inhibits the glycine binding sites on NMDA receptors. It follows that the effect of glutamate on early postdenervation depolarization is mediated by the NMDA subtype of glutamate receptor with similar pharmacological properties to those found in neurons. The only exception found was the glutamate-like action of 1×10?7 M MK-801, which partially prevented the early postdenervation depolarization when present in the muscle bath during the first 3 h after nerve section.  相似文献   
296.
A comprehensive clinical study on the effects of various aviation stresses on soft and semisoft contact lenses was carried out to find out their compatibility in aviation environment. Twenty subjects (11 aircrew and 9 non air-crew) participated in the study. Twelve of them were given soft lenses of water contents of 38%, 50% and 78% and rest 8 were given semisoft lenses of daily wear and extended wear type. The environmental trial consisted of exposure to hypoxia, rapid decompression, acceleration, pressure breathing, vibration and high temperature. On successful completion of environmental trials on ground simulators, the inflight trials on high performance aircraft, transport aircraft, passenger aircraft and helicopters were conducted. The soft lenses with low, medium and high water contents and extended wear semisoft lenses (large diameter) were found compatible with all types of aircraft flying.KEY WORDS: Aviation stresses, Acceleration, Contact lenses, Hypoxia, Vibration  相似文献   
297.
Antibacterial activity and phytochemical tests of eight whole plant methanol extracts belonging to family Euphorbiaceae were evaluated. In agar well diffusion assay the diameter of inhibition zones ranged from 3–13 mm. Phyllanthus emblica showed maximum activity of 13 mm. The MIC and MBC observed were 30–140 mcg/ml and 40–160 mcg/ml, respectively. P. piscatorum and P. emblica showed the lowest MIC (30 mcg/ml), P. emblica the lowest MBC (40 mcg/ml) and thus an effective inhibitor of the tested bacteria. Alkaloids, saponins and tannins were detected in 7 out of 8 tested plants.  相似文献   
298.
Reassortant strains for live influenza vaccine (LIV) were selected using two additional markers: intensity of cytopathic effect (CPE) at 40 degrees C in MDCK cells and toxicity for mice (induction of acute hemorrhagic pulmonary edema after intranasal challenge with undiluted virus). All wild-type viruses induced a high CPE in MDCK cells, while the reassortants differed by this sign. Only vaccine strains and attenuation donors were characterized by a low CPE. Modern epidemic viruses are highly toxic for mice, causing the death of 60-100% animals from hemorrhagic pulmonary edema on days 3-4 after intranasal infection. Attenuation donors and vaccine strains were not toxic for mice, the level of toxic effect correlating with CPE in MDCK culture. Evaluation of CPE in MDCK culture and toxicity for mice can be used for primary screening of candidates for LIV.  相似文献   
299.

Background  

YKL-40 (chitinase-3-like-1) is a member of "mammalian chitinase-like proteins". The protein is expressed in many types of cancer cells and the highest plasma YKL-40 levels have been found in patients with metastatic disease, short recurrence/progression-free intervals, and short overall survival. The aim of the study was to determine the expression of YKL-40 in tumor tissue and plasma in patients with borderline ovarian tumor or epithelial ovarian cancer (OC), and investigate prognostic value of this marker.  相似文献   
300.
Single administration of brain-derived neurotrophic factor (BDNF) into the lateral ventricle of ASC mice (Antidepressant Sensitive Catalepsy), a model of depression-like state, significantly decreased predisposition to cataleptic freezing in these animals. These findings indicate that BDNF can appear as a promising antidepressant of new generation and that ASC mice can be used as an adequate model for investigations of the mechanisms of behavior modification by BDNF.  相似文献   
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