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51.
铁皮石斛试管苗快速繁殖的研究   总被引:28,自引:0,他引:28  
兰科植物铁皮石斛(Dendrobium candidum Wall.ex Lind1.)的茎为常用名贵中药。多年来,主要依靠采收野生品种供药用和出口,致使野生资源枯竭,现已成为日益稀少的濒危植物。兰属种子和石斛属种子试管繁殖已积累不少资料,但是有关铁皮石斛种子试管繁殖的研究只有少量简单的报道,对其种子在试管繁殖过程中,所需外界条件的研究也不够  相似文献   
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BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
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We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs.  相似文献   
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We conducted a study of the 2 year cumulative incidence of trunkabnormalities in a cohort of 3,071 11 year old children (1,621boys, 1,450 girls). The following data were recorded: height,weight, signs of puberty and menarche. Trunk abnormality wasassessed in the erect child (asymmetry of shoulders and waistline,imbalance of the trunk, scoliosis, lordosis, kyphosis, swaybackand flexibility) and by the forward bending test (FBT) (ribhump or lumbar prominence, persisting scoliosis, kyphosis anddeviant lateral aspect). A normal FBT both at baseline and atfollow-up was found in 84% of the boys and in 79% of the girls.The 2 year cumulative incidence of an abnormal FBT was 10% inboys and 13% in girls.  相似文献   
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Rothner AD 《Headache》2003,43(4):427-428
Curr Pain Headache Rep. 2002;6:233-239.
This article reviews the less frequently encountered varieties of migraine. It is suggested that these disorders be approached by evaluating possible underlying etiologies before positively diagnosing migraine. This decreases the likelihood of "missing" structural or metabolic disorders. The classification, diagnostic evaluation, differential diagnosis, and treatment options of these disorders is reviewed and a selection of references appended for additional information.
Comment: Dr. Rothner is one of the most prominent pediatric neurology headache specialists in the country, and he sees a variety of atypical presentations of migraine. This is an excellent review of such presentations. SJT  相似文献   
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