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91.
Functional interleukin 2 receptors on B cells lacking Tac antigens   总被引:3,自引:0,他引:3  
Human B lymphoblastoid line, SKW 6-4, cells were induced to IgM-secreting cells by high concentrations of interleukin 2 (IL 2). These cells were found to be unreactive with anti-Tac antibody and did not express mRNA detectable for Tac antigen. In Scatchard plot analysis, low-affinity IL 2-binding sites were found on SKW 6-4 cells. Moreover, analysis of the IL 2-binding molecules revealed ones (molecular weight 70,000 and 75,000) distinct from Tac antigen. It is conceivable that IL 2 exerts its effect through its interaction with these novel IL 2-binding molecules in SKW 6-4 cells.  相似文献   
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93.
It is well known that non Hodgkin's lymphoma (NHL) cells express various antigens which are normally involved in a variety of functions. In addition, NHL is diverse in its proliferative capacity. To investigate the relation between these factors and the clinical picture, 45 cases of NHL were studied by immunohistochemistry using snap-frozen materials obtained before therapy. Reactivities with 27 monoclonal antibodies were examined and the results were correlated with clinical findings. The expression of surface μ and CAM-1 in B-NHLs and CD25 in T-NHLs were significantly associated with bone marrow involvement. B-NHLs without expression of CD21(B2) and T-NHLs with CD25 were seen more frequently in cases with a LDH value of over 500 units/ml. The positivity rate of Ki-67 on B-NHLs was correlated with serum LDH value, NHL histologic classification, and overall survival. These data indicate that immunophenotyping and determination of the proliferative capacity of NHL are of value not only for confirmation of the histopathologic classification of the tumor but also for assessment of clinical behavior.  相似文献   
94.
The structural basis of the high affinity interleukin-2 receptorwhich was previously reconstituted in a cultured murine T cellline, EL4 by expressing either wild-type Tac antigen complementaryDNA (cDNA) or a chimeric cDNA was characterized. The chimericcDNA encodes a membrane portion whose extracellular portionconsists of that of Tac antigen whereas transmembrane and cytoplasmicportions consists of those the human insulin beta chain. TheTac antigen/anti-Tac antibody complex was treated by chemicalcrosslinking reagents, purified by goat anti-mouse immunoglobulin(lg), and was analysed by SDS–PAGE. We here demonstrated the presence in mouse EL4 transfectantsof a novel membrane protein which is closely associated withthe products of transfected cDNAs in the absence of interleukln-2.The protein is 75 kDa in size and is detected in cells whichexpress high affinity interieukln-2 receptor but not in cellswhich only express low affinity interleukin-2 receptor. Thetransmembrane region and the cytoplasmic region of Tac antigenis not necessary for the formation of the complex consistingof Tac antigen and 75 kDa molecule, indicating that a murine75 kDa molecule associates with Tac antigen extra-cellularly.  相似文献   
95.
STUDY OBJECTIVES: Sleep deprivation has a profound effect on cardiovascular regulation through the autonomic nervous system. This study examined the effect of 24-hour total sleep deprivation on muscle sympathetic nerve activity (MSNA), which is a direct measurement of the postganglionic sympathetic efferent innervating the vascular bed in the skeletal muscle and other circulatory structures. DESIGN: The study was performed on 6 young healthy men. The factors exerting influence on MSNA, such as aging, obesity, body posture, activity, intensity of illumination, and food and beverage consumption were strictly controlled. Burst rate and burst incidence were used as parameters of MSNA. The burst rate, burst incidence, heart rate, and systolic and diastolic blood pressure were measured after total sleep deprivation and control sleep. To perform a linear regression analysis of arterial baroreflex (ABR), the incidence of MSNA bursts corresponding to a given diastolic blood pressure (%MSNA) was examined. MEASUREMENT AND RESULTS: The diastolic blood pressure was significantly higher after total sleep deprivation than after control sleep (66.5 +/- 1.7 vs 57.4 +/- 3.3 mm Hg). The burst rate (9.6 +/- 1.8 vs 13.3 +/- 2.7 bursts/min) and burst incidence (21.6 +/- 4.5 vs 30.3 +/- 8.9 bursts/100 heart beats) of MSNA were significantly lower after total sleep deprivation than after control sleep (P < .05). Analysis of the ABR disclosed a significant linear regressive relation between %MSNA and diastolic blood pressure in every subject after both total sleep deprivation and control sleep. This result implies that the ABR regulates the occurrence of MSNA bursts under different diastolic blood pressure conditions. The threshold (X-axis intercept) of the blood pressure regression line (ie, an indicator of the ABR set point) shifted by 12 +/- 4.3 mm Hg toward a higher blood pressure level after total sleep deprivation (P < .05). The ABR sensitivity, or the slope of the regression line, tended to be less steep after total sleep deprivation than after control sleep, although it was not statistically significant (P = .09). CONCLUSIONS: The diastolic blood pressure increased and both burst rate and burst incidence of MSNA decreased after total sleep deprivation. The results show that resetting of the ABR toward a higher blood pressure level occurred after total sleep deprivation. This ABR resetting probably brings about an increase in arterial blood pressure after total sleep deprivation.  相似文献   
96.
A phase I study ofN 4-behenoyl-1-β-d-arabinofuranosylcytosine (BHAC) was conducted in 66 patients, 41 with solid tumors and 25 with hematological malignancies. The patients received either a 2-h single intravenous (i.v.) drip infusion (Schedule 1) or consecutive daily 2-h i.v. infusions (Schedule 2). In Schedule 1 the daily dose was initiated with 1.5 mg kg?1 which was escalated up to 7 mg kg?1. Side-effects were mild, and included nausea, vomiting, epilation, and hot flushes. Because of the presence of the solvent vehicle, HCO-60 and in consideration of the mechanism of action of BHAC, the dose escalation was stopped at 7 mg kg?1. In Schedule 2, the daily dose was started with 1.5 mg kg?1 which was escalated up to 8 mg kg?1 and given for 2–16 days. Myelosuppression was found to be dose-limiting toxicity. The maximum tolerated dose (MTD) in patients with non-hematological solid tumors was assumed to be 5 mg kg?1 daily × 5 days. The plasma disappearance curve of BHAC looked biphasic, and when 4 mg kg?1 of BHAC were administered the half-lives of the initial phase (t 1/2α) and the second phase (t 1/2β) were calculated as 0.798 and 5.76 h respectively. In Schedule 2 complete remission was observed in 5 out of 21 patients with acute leukemia, one partial remission in Hodgkin’s disease, and one 1-B response (Karnofsky) in thyroid papillary adenocarcinoma.  相似文献   
97.
98.
Summary Transverse osseous structure of the carpal groove was studied using serial sections and microradiography. The width and area of the carpal groove were measured in x-ray films of each section. The wrist and carpal region was divided into six levels: 1) radio-ulnar joint level, 2) proximal level of the carpal bones, 3) intermediate level of carpal bones, 4) distal level of carpal bones, 5) the first C-M joint level, and 6) bases of the metacarpal bone level. The width of the carpal groove averaged 32 mm at the inlet and became narrower toward the outlet. Both inlet and outlet areas were small, the largest area was observed at the middle part. Although the carpal bones did not support the body weight, a remnant of the trajectorial architecture of the trabeculae was observed.
La structure osseuse de la gouttière carpienne
Résumé La structure transversale des os de la gouttière carpienne a été étudiée à l'aide de coupes et par microradiographie. L'épaisseur et la superficie de la gouttière carpienne ont été mesurées sur des clichés aux rayons X de chacune de ces coupes. La région du poignet et du carpe a été divisée en six rangées: 1) la rangée de l'articulation radiocubitale, 2) la rangée proximale des os du carpe, 3) la rangée intermédiaire des os du carpe, 4) la rangée distale des os du carpe, 5) la rangée de la première articulation C-M et 6) la rangée de la base des os du métacarpe. L'épaisseur moyenne de la gouttière carpienne atteignait 32 mm à l'entrée, se rétrécissant en direction de la sortie. Tant la zone d'entrée que celle de sortie étaient de superficie réduite, la superficie la plus importante étant observée dans la partie médiane. Si les os du carpe ne supportent pas le poids du corps, un reste de structure trajectorielle des travées a cependant été observé.
  相似文献   
99.
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function.  相似文献   
100.
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