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991.
992.
Sharkis  SJ; Santos  GW; Colvin  M 《Blood》1980,55(3):521-523
Cell suspensions of normal rat marrow mixed with rat acute myelogenous leukemic cells were prepared and incubated in vitro with graded doses of 4-hydroperoxycyclophosphamide (4HC). The cell suspensions were injected into rats prepared with a lethal dose of total body irradiation. Animals injected with these cells survived fatal irradiation induced aplasia. In a dose related manner 4HC was able to "purge" tumor cells from the cell mixtures. Thus, animals given cell suspensions incubated with the lower doses of 4HC showed prolonged survival before death from leukemia and animals given cell suspensions incubated with higher doses of 4HC survival lethal irradiation without the subsequent appearance of leukemia. These studies clearly establish that tumor cells may be eliminated from normal marrow suspensions without completely destroying the pluripotent stem cells.  相似文献   
993.
BACKGROUND & AIMS: Helicobacter infection of the gastric antrum is responsible for a number of gastric disorders. Antibiotic therapy is lengthy and is not always effective. It has been shown previously that oral immunization against Helicobacter felis in mice can prevent colonization after challenge. The aim of this study was to investigate the efficacy of therapeutic immunization in eradicating an established Helicobacter infection and in reducing gastritis. METHODS: Domestic ferrets, confirmed to be infected with Helicobacter mustelae by gastric endoscopy, were orally immunized with varying doses of purified Helicobacter pylori urease in combination with the mucosal adjuvant cholera toxin. Ferrets were assessed 1 week and 6 weeks after treatment for infection and pathology. RESULTS: Therapeutic immunization eradicated Helicobacter colonization in 30% of all immunized ferrets, although there was no difference in efficacy between the varying doses of antigen tested. The difference was statistically significant when compared with animals administered cholera toxin alone or buffer (P = 0.04). The intensity of inflammation was also significantly reduced in immunized animals (P = 0.0003). CONCLUSIONS: Oral immunization with purified H. pylori urease and cholera toxin can eradicate H. mustelae in a natural host pathogen model. Oral immunization of chronically infected animals markedly reduced gastric inflammation. (Gastroenterology 1996 Jun;110(6):1770-5)  相似文献   
994.
Hematopoietic growth factors have been used to accelerate engraftment after bone marrow transplantation and to "mobilize" peripheral blood progenitor cells (PBPC). We report on the data in 85 consecutive patients with Hodgkin's disease who were treated in a single institution using different methods to obtain PB progenitor cells. Use of granulocyte colony-stimulating factor for mobilization resulted in a significantly accelerated time to recovery of granulocytes (10 days v 12 days, P < .01) when compared with "nonmobilized" PBPC recipients. Similarly, use of mobilized PBPC resulted in a significantly accelerated time to platelet engraftment (13 days v 30 days, P < .001) when compared with "nonmobilized" recipients. Moreover, there was a statistically significant difference in total costs in favor of the group receiving "mobilized" PBPC.  相似文献   
995.
肝包虫囊肿周围纤维囊壁病理结构的再认识   总被引:19,自引:1,他引:19  
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996.
The integrin alpha IIb beta 3, a calcium-dependent heterodimer, plays a critical role in platelet aggregation. The alpha IIb subunit of the heterodimer contains four highly conserved putative calcium-binding domains in its extracellular portion. During studies of the molecular basis of Glanzmann thrombasthenia in a child of mixed Caucasian background whose platelets expressed little alpha IIb beta 3 on their surface, we found the patient heterozygous for a two amino acid deletion in the fourth alpha IIb calcium-binding domain. When this alpha IIb mutant was expressed in COS-1 cells, we found that the deletion did not interfere with the assembly of alpha IIb beta 3 heterodimers, but altered their conformation such that they were neither recognized by the heterodimer-specific antibody A2A9 nor able to undergo further intracellular processing or transport to the cell surface. These results suggest that the calcium-binding domains in alpha IIb play an important role maintaining the overall conformation of alpha IIb beta 3. To confirm this suggestion, we deleted each of the four 12 amino acid calcium-binding domains in alpha IIb by in vitro mutagenesis and expressed the mutants along with beta 3 in COS-1 cells. Each construct formed a heterodimer with beta 3, but none of the heterodimers interacted with A2A9 or underwent further intracellular processing. These data indicate that the calcium-binding domains in alpha IIb are not involved in alpha IIb beta 3 heterodimer formation, but their presence is required for the intracellular transport of alpha IIb beta 3 to the cell surface.  相似文献   
997.
The ability of an infusion of ex vivo expanded hematopoietic cells to ameliorate cytopenia following transplantation of hematopoietic stem cells (HSCs) is controversial. To address this issue, we measured the recovery of circulating leukocytes, erythrocytes, and platelets in lethally irradiated mice transplanted with 10(3) enriched HSCs, with or without their expanded equivalent (EE) generated after 7 days of culture in interleukin-3 (IL-3), IL-6, granulocyte colony-stimulating factor and Steel Factor. Two HSC populations differing in their content of short-term repopulating progenitors were evaluated. Thy-1loLIN-Sca- 1+ (TLS) bone marrow (BM) is enriched in colony-forming cells (CFCs), day 8 and day 12 spleen colony-forming units (CFU-S) (435 +/- 19, 170 +/- 30, and 740 +/- 70 per 10(3) cells, respectively), and stem cells with competitive long-term repopulating potential (> or = 1 per 43 cells). Thy-1loSca-1+H-2Khl cells (TSHFU) isolated from BM 1 day after treatment of donor mice with 5-fluorouracil (5-FU) are also highly enriched in competitive repopulating units (CRU, > or = 1 per 55 cells), but are depleted of CFCs, day 8 and day 12 CFU-S (171 +/- 8, 0 and 15 +/- 4 per 10(3) cells, respectively). Recipients of 10(3) TLS cells transiently recovered leukocytes to > or = 2,000/microL in 12 days, but sustained engraftment required 25 days. Platelets recovered to > or = 200,000/microL in 15 days, and erythrocytes never decreased below 50% of normal. Mice transplanted with 10(3) TSHFU cells recovered leukocytes in 15 days, and platelets and erythrocytes in 18 days. Recipients of unseparated normal or 5-FU-treated BM cells (containing 10(3) TLS or TSHFU cells) recovered safe levels of blood cells in 9 to 12 days, suggesting that unseparated marrow contains early engrafting cells that were depleted by sorting. Upon ex vivo expansion, total cells, CFCs and day 12 CFU-S were amplified 2,062-,83- and 13-fold, respectively, from TLS cells; and 1,279-, 259- and 708-fold, respectively, from TSHFU cells. Expanded cells could regenerate the majority of lymphocytes and granulocytes in primary (17 weeks) and secondary (26 weeks) hosts and were only moderately impaired compared to fresh HSCs. The EE of TSHFU cells was more potent than that of TLS cells, suggesting that more highly enriched HSCs are more desirable starting populations for this application. When mice were transplanted with 10(3) TSHFU cells and their EE, the duration of thrombocytopenia was shortened from 18 to 12 days, and anemia was abolished. Leukocytes were also elevated on days 9 to 12, although sustained recovery was not accelerated. Anemia was also abrogated in recipients of 10(3) TLS cells and their EE. Early platelet counts were slightly higher than with TLS cells alone, but leukocyte recovery was not improved. These data confirm that TLS cells contribute to early and sustained hematopoiesis, and demonstrate a benefit of ex vivo expanded cells in accelerating engraftment of more primitive TSHFU stem cells depleted of progenitors.  相似文献   
998.
999.
Obstructive sleep apnea is a prevalent sleep disorder characterized by partial or complete obstruction of the upper airway. Continuous positive airway pressure is the first-line therapy for most patients, but adherence is often poor. Alternative treatment options such as mandibular advancement devices, positional therapy, and surgical interventions including upper airway stimulation target different levels and patterns of obstruction with varying degrees of success. Drug-induced sleep endoscopy enables the visualization of upper airway obstruction under conditions mimicking sleep. In the era of precision medicine, this additional information may facilitate better decision-making when prescribing alternative treatment modalities, with the hope of achieving better adherence and/or success rates. This review discusses the current knowledge and evidence on the role of drug-induced sleep endoscopy in the non-positive airway pressure management of obstructive sleep apnea.  相似文献   
1000.
Objective: Rheumatoid arthritis (RA) is an inflammatory disease with increased mortality from cardiovascular disease (CVD). Oxidative stress has a critical role in the pathogenesis of RA and CVD. Sesamin, the main lignin constituent of sesame, has several antioxidant and anti-inflammatory effects. This study aimed to investigate the effects of sesamin supplementation on anthropometric indices, lipid profile, blood pressure, and oxidative stress markers in women with RA.

Methods: In this randomized, double-blind, placebo-controlled clinical trial, 44 patients with RA were randomly divided into 2 groups (intervention and control). Patients consumed 200 mg/day sesamin supplement and placebo in the intervention and control groups, respectively, for 6 weeks (spring 2014). At baseline and at the end of the study, anthropometric indices and blood pressure were assessed. Serum concentrations of lipid profile, malondialdehyde (MDA), and total antioxidant capacity (TAC) were also determined.

Results: At the end of study, sesamin supplementation significantly decreased serum levels of MDA (p = 0.018) and increased TAC and high-density lipoprotein cholesterol (HDL-C) levels in patients with RA (p = 0.020 and p = 0.007, respectively). In the sesamin group, the mean of weight, body mass index, waist-to-hip ratio, body fat, systolic blood pressure, and the concentration of other lipid profiles (triglycerides, total cholesterol, and low-density lipoprotein cholesterol [LDL-C]) were also significantly decreased at the end of study compared to baseline values (p < 0.05). However, the difference between the 2 groups was not statistically significant in this regard (p > 0.05).

Conclusion: Sesamin exhibited a protective effect on cardiovascular risk factors in patients with RA. However, further investigation is suggested.  相似文献   

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