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71.
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73.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
74.
股方肌肌骨瓣植入治疗成人股骨头缺血性坏死   总被引:1,自引:0,他引:1  
目的:目前成人股骨头缺血性坏死的手术方法较多,但远期疗效大多不肯定。股方肌肌骨瓣植入术可以治疗成人股骨头缺血性坏死,但需验证其近远期疗效。方法:选择2001-01/2007-01铜川市矿务局中心医院骨科收治的股方肌肌骨瓣植入治疗股骨头坏死患者15例(18髋),均知情同意。术中暴露股方肌及其在股骨近端的附着点,于附着点处凿取骨瓣,骨瓣为4cm×1.5cm×1.0cm的长方形,将骨瓣插入股骨头内,远端用可吸收骨钉固定。术后3,6,12,24个月门诊复查拍患髋正位和蛙式位X射线片,根据临床查体和X射线片表现将手术效果分为优、良、差3级。结果:全部患者均获随访,随访时间4~36个月。近期疗效满意,出院时疼痛症状均缓解,未见手术相关并发症。中远期随访结果优10髋,良6髋,差2髋,优良率88.9%。结论:股方肌肌骨瓣植入术治疗成人股骨头缺血性坏死近远期疗效确切,手术操作相对简单。  相似文献   
75.
SUMMARY This double-blind, randomised, cross-over study investigated the antihypertensive efficacy of ramipril and enalapril was completed by 30 patients with mild-to-moderate essential hypertension. After a four-week placebo run-in phase, the patients received either 2.5mg ramipril or 10mg enalapril once daily for four weeks. The dosages were increased to 5mg ramipril and 20mg enalapril for a further four weeks. After a placebo washout phase of four weeks, the patients were crossed over to the alternative treatment. The decrease in average 24-hour ambulatory diastolic blood pressure from week 0 to week 8 was 1.6mmHg greater with ramipril than enalapril (90% confidence interval 0.6-2.7mmHg). The corresponding reduction in for systolic blood pressure was also greater with ramipril than enalapril by 2.4mmHg (90% confidence interval: 0.5-4.2mmHg). For the difference in the drop of 24-hour ambulatory diastolic blood pressure between ramipril and enalapril the lower level of the 90% confidence interval (CI) is above the clinically relevant difference of -3mmHg. This is an indication that ramipril (2.5 and 5mg dose) is at least as effective as enalapril (10 and 20mg dose) in decreasing blood pressure in patients with mild-to-moderate essential hypertension. The duration of adequate antihypertensive effect was relatively long for both ramipril and enalapril; however, ramipril tended to have a more prolonged antihypertensive effect. Ramipril had a higher diastolic and systolic trough/peak ratio than enalapril, resulting in a more uniform antihypertensive effect over the 24-hour treatment period. Both ramipril and enalapril were well tolerated and the two treatment groups had similar safety profiles.  相似文献   
76.
目的:制备大鼠在体缺血再灌注模型,观察缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化。方法:实验于2005-03/2006-10在解放军沈阳军区总医院医学实验动物中心和全军心血管研究所实验室完成。实验分组:选用健康雌性SD大鼠36只,根据预适应程序分为第1,2,3次缺血,第1,2,3次再灌注,每一时间点6只大鼠。实验过程:用手术套管法造成左冠状动脉主干缺血及再灌注。所有实验动物在实验程序结束后,取出心脏迅速置液氮保存备用。实验评估:用放射免疫法测环磷酸腺苷水平,生化法测环磷酸腺苷依赖蛋白激酶活性变化。结果:36只大鼠均进入结果分析。①环磷酸腺苷含量:第1次再灌注组低于第1次缺血组[(0.325±0.015),(0.395±0.024)pmol/g,t=6.06,P<0.001],第2次再灌注组低于第2次缺血组[(0.523±0.017),(0.708±0.067)pmol/g,t=6.56,P<0.001],第3次再灌注组低于第3次缺血组[(0.567±0.031),(0.712±0.038)pmol/g,t=7.24,P<0.001]。②环磷酸腺苷依赖蛋白激酶活性:第1次再灌注组低于第1次缺血组[(10.115±1.000),(16.351±0.849)pkat/g,t=11.12,P<0.001],第2次再灌注组低于第2次缺血组[(11.877±2.213),(14.869±0.619)pkat/g,t=3.31,P<0.01],第3次再灌注组低于第3次缺血组[(11.745±0.987),(14.766±0.329)pkat/g,t=7.09,P<0.001]。③缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性随缺血及再灌注呈周期性波动。在5min缺血预处理时表现为明显增高,而在间隔的再灌注程序中恰呈相反改变,有明显下降的趋势。结论:环磷酸腺苷及环磷酸腺苷依赖蛋白激酶的周期性波动变化可能是激发心肌缺血预处理的机制之一,环磷酸腺苷可能在预处理保护作用中起一些作用。  相似文献   
77.
Pain in chronic pancreatitis(CP) shows similarities with other visceral pain syndromes(i.e.,inflammatory bowel disease and esophagitis),which should thus be managed in a similar fashion.Typical causes of CP pain include increased intrapancreatic pressure,pancreatic inflammation and pancreatic/extrapancreatic complications.Unfortunately,CP pain continues to be a major clinical challenge.It is recognized that ongoing pain may induce altered central pain processing,e.g.,central sensitization or pro-nociceptive pain modulation.When this is present conventional pain treatment targeting the nociceptive focus,e.g.,opioid analgesia or surgical/endoscopic intervention,often fails even if technically successful.If central nervous system pain processing is altered,specific treatment targeting these changes should be instituted(e.g.,gabapentinoids,ketamine or tricyclic antidepressants).Suitable tools are now available to make altered central processing visible,including quantitative sensory testing,electroencephalograpy and(functional) magnetic resonance imaging.These techniques are potentially clinically useful diagnostic tools to analyze central pain processing and thus define optimum management approaches for pain in CP and other visceral pain syndromes.The present review proposes a systematic mechanism-orientated approach to pain management in CP based on a holistic view of the mechanisms involved.Future research should address the circumstances under which central nervous system pain processing changes in CP,and how this is influenced by ongoing nociceptive input and therapies.Thus we hope to predict which patients are at risk for developing chronic pain or not responding to therapy,leading to improved treatment of chronic pain in CP and other visceral pain disorders.  相似文献   
78.
JH Lee  ; HG Klein 《Transfusion》1995,35(5):384-388
BACKGROUND: Granulocyte collection relies on the use of a red cell- sedimenting agent and is influenced by poorly defined intrinsic donor characteristics. The donor's baseline red cell (erythrocyte) sedimentation rate (ESR), a readily measurable intrinsic donor variable, may influence the effectiveness of red cell-sedimenting agents and affect the granulocyte yield. STUDY DESIGN AND METHODS: The in vitro and in vivo effects of 6-percent hydroxyethyl starch on the donor ESR were prospectively studied in 67 granulocytapheresis procedures with a blood cell separator, and the findings were correlated with granulocyte collection efficiency (GCE). A relationship that predicts the GCE on the basis of the donor ESR was then derived and tested. RESULTS: The 3.7-fold mean increase in the donor ESR measured after in vitro addition of hydroxyethyl starch approximated the 3.3-fold increase measured when it was administered to the donors. Higher baseline ESR correlated with larger in vitro and in vivo hydroxyethyl starch-induced increases in ESR and predicted more efficient cell collections and greater cell yields. Furthermore, both ESR and GCE, which varied significantly among donors, remained constant for a given donor undergoing repeat procedures. The results could be summarized by a simple predictive formula that relates the GCE (%) to the ESR (mm/hour): GCE = 1.3ESR + 45. The GCE and yield as predicted by the formula were accurate within 10 percent of the observed values in six subsequent procedures. CONCLUSION: In granulocyte harvests using a blood cell separator with hydroxyethyl starch as the sedimenting agent, 1) both ESR and GCE vary widely among donors yet may remain relatively constant for a given donor; 2) the baseline ESR correlates with hydroxyethyl starch-modified ESR and with GCE; and 3) it may be possible to predict GCE and yield from the donor's baseline ESR.  相似文献   
79.
Klingemann  HG; Tsoi  MS; Storb  R 《Blood》1986,68(1):102-107
Prostaglandins are said to influence T and B cell function by inhibiting the generation of interleukin 2 (IL 2) and the formation of suppressor lymphocytes. After bone marrow transplantation, patients usually have a profound immunodeficiency that persists in recipients with chronic graft-v-host disease (GVHD) and generally resolves in long- term survivors without GVHD. In vitro tests of lymphocyte function such as allogeneic mixed lymphocyte culture (MLC) and cell-mediated lympholysis (CML) have been shown to be impaired in many patients. We postulated that prostaglandin E2 (PGE2) plays a role in the impaired in vitro tests. To test this hypothesis, we studied in vitro tests in the presence of PGE2 antagonists, indomethacin, and anti-PGE2 antiserum with cells from 22 short-term patients (less than 100 days postgrafting) and 32 long-term survivors with or without GVHD. Results show that blockade of PGE2 release by indomethacin and anti-PGE2 significantly (P less than .01) enhanced the MLC (+67%) and the CML responses (+10.5%) of cells from long-term survivors with chronic GVHD but not from those of long-term, stable recipients. No enhancement of MLC and CML activity was observed with cells from donors of long-term recipients. In patients shortly after marrow grafting, enhancement in the MLC was not significant. However, CML activity in this patient group was significantly increased (+12.5% in recipients with no GVHD, 8.5% in those with acute GVHD, P less than .01). Indomethacin also suppressed the activity of nonspecific suppressor cells in patients with chronic GVHD. When cells from patients with chronic GVHD were treated with recombinant IL 2 and IL 2 combined with indomethacin, it was possible to get an additional augmentation of lymphocyte proliferation after the addition of indomethacin to IL 2-treated cultures. Thus it is very likely that PGE2 inhibits T lymphocyte proliferation, not exclusively by inhibition of IL2 production or activity. We conclude that PGE2, among other factors, may play a role in the pathogenesis of the immunodeficiency after transplantation. PGE2 does not act primarily by interfering with IL2 but presumably by inducing a suppressorlike activity.  相似文献   
80.
患者为1例39岁女性,患T/NK细胞淋巴瘤,在外周血异基因干细胞移植后15天,发生环孢素A(CSA)毒性相关的微血管病溶血性贫血(MAHA).因血清肌酐从移植前的0.4mg/dL,上升至移植后第9和15天的1.0和2.9 mg/dL.故停用CSA.  相似文献   
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