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41.
目的探讨单核细胞向巨噬细胞分化过程中CD44 mRNA表达和黏附功能的变化。方法应用豆蔻佛波醇乙酯(PMA)诱导单核细胞系U937向巨噬细胞分化;应用RT-PCR分析U937细胞CD44 mRNA表达变化,并以β-actin作为内参进行半定量评价,并对主要条带进行测序;应用荧光染料BCECF/AM作为探针,测定黏附于激活的内皮细胞上的U937细胞数目。结果与对照组比较,PMA诱导的U937细胞CD44 mRNA总体表达显著增加(P=0.01037),异构体/标准CD44比例显著上升(P=0.0005551),测序结果显示PMA刺激后显著增加的是947 bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体。同时,PMA刺激后U937细胞黏附功能显著增加(P=0.0029)。结论单核细胞向巨噬细胞分化过程中CD44 mRNA,特别是947bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体的表达显著增加,可能与细胞黏附功能的增强相关。  相似文献   
42.
RNA Synthesis in Cultures of Normal Human Peripheral Blood   总被引:6,自引:0,他引:6  
RNA and DNA synthesis were measured in cultures of normal human peripheral blood using tritiated cytidine and thymidine and autoradiographictechnics. RNA synthesis preceded DNA synthesis by 24 hours. RNA synthesisoccurred predominantly in the large and medium-sized "blast-like" cells, butdid occur, to a lesser extent, in the small lymphocytes. RNA synthesis did notoccur in the absence of phytohemagglutinin, nor did DNA synthesis. Mechanisms of action of phytohemagglutinin are discussed with particular referenceto its possible antigenic nature.

Submitted on August 12, 1963 Accepted on January 6, 1964  相似文献   
43.
We studied the interaction between paracetamol (acetaminophenU.S.P.) and enflurane. Sixteen rats were assigned to four groups(n=4) to receive: paracetamol 7.5 mg/100 g body weight; paracetamolplus 1% enflurane; 1% enflurane alone, or no treatment (controls).Animals were killed 6 h later. A second series of 16 were treatedidentically, but were killed after 24 h. Measurements were madeof fluoride concentrations in serum, liver and urine (indicatorsof biotransformation of enflurane), paracetamol concentrationsin urine, pathological changes in liver samples, and concentrationsof the enzymes aspartate aminotransferase (AST) and alanineaminotransferase (ALT) in serum. Pretreatment with paracetamolsignificantly decreased urinary fluoride at 6 and 24 h afterexposure to enflurane, but decreased fluoride concentrationsin serum and liver only at 6 h after exposure to enflurane.Paracetamol concentrations in urine did not change after exposureto enflurane. Exposure to paracetamol alone increased AST andALT. At 24 h after exposure to enflurane, serum concentrationsof enzymes in rats pretreated with paracetamol were similarto those of control rats. Pretreatment with paracetamol maytherefore inhibit metabolism of enflurane. Although no hepaticdamage was observed, the increased in AST and AL T suggestedsubclinical liver damage in rats given only paracetamol.  相似文献   
44.
Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
45.
Effects of alfentanil, preceded by lorazepam, on suppressionof haemodynamic and somatic responses to noxious stimuli wasstudied in patients undergoing CABG. Plasma concentration ofalfentanil, somatic and haemodynamic responses were measuredat loss of consciousness, tracheal intubation, sternotomy andduring multiple applications of electrocoagulation. Additionalalfentanil was administered i.v. to control unwanted responses.Study 1 (six patients): lorazepam 0.08 mg kg–1 by mouth1–2 h before operation, alfentanil priming infusion (60µg kg–1 min–1 for 10 min) followed by maintenanceinfusion (4.5 µg kg–1 min–1). With mean plasmaalfentanil 1178 (SEM 54) ng ml–1, two patients requiredsupplementary alfentanil to suppress somatic motor responses;one patient required nitroglycerin to control an increase inarterial pressure which was unresponsive to additional alfentanilfollowing sternotomy. Study 2 (13 patients): lorazepam 0.04mg kg–1 by mouth as premedication; one of three maintenanceinfusion rates of alfentanil: 5.4 (n=4), 6.6 (n=5), or 7.8 (n=4)µg kg–1 min–1, each preceded by a proportionalpriming infusion. With plasma alfentanil 2181 (62)ng ml–1,somatic motor responses requiring additional alfentanil occurredin nine patients; haemodynamic responses in four of seven patientstested could not be controlled by alfentanil. The highest plasmaconcentration of alfentanil to prevent response to a stimulusother than tracheal intubation was different between the twostudies (P<0.05). We conclude that alfentanil alone is insufficientto suppress haemodynamic and somatic motor responses to noxiousstimulation during CABG and that the role of premedication issignificant. *Department of Anesthesia, Bowman-Gray School of Medicine Winston-Salem,NC 27103, U.S.A. 2114 de Mayo Road, Del Mar, Ca. 92014, U.S.A.  相似文献   
46.
Megakaryocyte Maturation Rate in Thrombocytopenic Rats   总被引:3,自引:0,他引:3  
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47.
Intraspinal synovial cysts: MR imaging   总被引:3,自引:0,他引:3  
Jackson  DE  Jr; Atlas  SW; Mani  JR; Norman  D 《Radiology》1989,170(2):527-530
Juxtaarticular intraspinal synovial cysts are unusual lesions of the spine associated with facet arthropathy. These lesions can cause radicular symptoms and may masquerade clinically as other, more common entities. Synovial cysts have been detected at myelography and have been well characterized at computed tomography as posterolateral epidural masses, typically at L4-5. Six synovial cysts of the lumbar spine were demonstrated on magnetic resonance (MR) images. The signal-intensity patterns of these lesions are variable. MR imaging can be used to document the presence of hemorrhage within the cyst, which may relate to the exacerbation of symptoms. Air-filled synovial cysts may be difficult to detect and distinguish from facet arthropathy.  相似文献   
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