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1.
Two-stage stimulation of SK activity of normal human peripheral blood lymphocytes by soluble factors was demonstrated. The first stage was initiated by factors present in supernatant derived from normal B-LCL cultures. Only cell lines which could induce SK activity in culture in an MLR-type reaction had the capacity to produce the active factor. Supernatant factor required adherent cells to cause SK augmentation. The interaction of adherent cells plus supernatant factor resulted in the production of a second soluble factor which stimulated an increase in SK activity in responding lymphocyte populations. This second stage involved a different soluble factor which acted directly on the non-SK, Fc-negative lymphocyte population, and within 3 hr. Data obtained using antisera to interferon (IF) indicated that IF is a component of the second soluble factor, and not of the supernatant factor derived from the B-LCL. 相似文献
2.
Contractile properties of synthetic cationic polypeptides in guinea-pig isolated trachea. 总被引:2,自引:2,他引:0
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1. Purinoceptor agonist-induced currents in untreated (proliferating) and lipopolysaccharide- (LPS; 100 ng ml-1) treated (non-proliferating) rat microglial cells were recorded by the whole-cell patch-clamp technique. 2. In non-proliferating microglia, adenosine (0.01-100 microM), 2-methylthio ATP (3-3000 nM), ATP (0.1-1000 microM), and ATP-gamma-S (1-10 microM), but not alpha,beta-methylene ATP (alpha,beta-MeATP; 100 microM) produced a slow outward current at a holding potential of 0 mV. When K+ was replaced in the pipette solution by an equimolar concentration of Cs+ (150 mM), the 2-methylthio ATP- (300 nM) induced outward current disappeared. The effect of 2-methylthio ATP (300 nM) did not depend on the presence of extracellular Mg2+ (1 mM). The outward current response to 2-methylthio ATP (300 nM) was larger in proliferating than in non-proliferating microglia. 3. ATP (1-1000 microM) evoked a fast inward current at a holding potential of -70 mV in nonproliferating microglia, while adenosine (100-1000 microM) was inactive. When the effects of ATP were compared at 0 and -70 mV, it became evident that ATP is much more potent in evoking the outward current. 4. The 2-methylthio ATP- (300 nM) induced outward current was blocked by suramin (300 microM), but not by 8-(p-sulphophenyl)-theophylline (100 microM), while the adenosine- (1 microM) induced outward current had the reverse sensitivity to these antagonists.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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6.
The pineal gland and reproduction 总被引:2,自引:0,他引:2
The hormonal activity of the pineal gland is influenced by boththe dark-light cycle and the seasonal cycle, causing it to playan important role in the neuroendocrine control of reproductivephysiology. This is especially evident in seasonally breedinganimals, in which reproductive function is clearly influencedby seasonal variations in the duration of night and day. Humansare not seasonal breeders. Nevertheless, seasonal fluctuationshave been described in human reproduction, and the pineal glandalso appears to exert an important role in the neuroendocrineregulation of human reproductive physiology. There is evidencethat the epiphysis is involved in the control of sexual maturation.In rats, the maternal pineal appears to influence the gonadaland genital development and function of offspring; this hypothesishas yet to be confirmed in humans. The pineal apparently influenceshuman reproductive function not only at the hypothalamic-pituitarylevel, by inhibition of the hypothalamic pulsatile secretionof gonadotrophin-releasing hormone, but also at the gonadallevel, where melatonin receptors have also been found. In addition,melatonin is reported to increase serum prolactin concentrationsin both rats and humans. It has been suggested that melatoninis involved in the control of menstrual cyclicity. 相似文献
7.
G B Catalano N Cavallaro P Gangemi A Garozzo G Gorgone F Spina 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1988,196(4):200-203
A rare case of basosquamous carcinoma of the orbit invading the maxillary sinus is presented. The authors discuss clinical and pathological findings. Techniques for removal and reconstructive plastic surgery are reported. 相似文献
8.
Autoradiographic localization of beta-adrenoceptors in pig lung using [125I]-iodocyanopindolol. 总被引:1,自引:1,他引:0
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R. G. Goldie J. M. Papadimitriou J. W. Paterson P. J. Rigby D. Spina 《British journal of pharmacology》1986,88(3):621-628
The binding of the beta-adrenoceptor radioligand [125I]-iodocyanopindolol (I-CYP) has been studied in pig lung parenchyma and the distribution of binding sites visualised by light microscopic autoradiography. I-CYP binding was saturable (maximum binding capacity Bmax = 51 +/- 3 fmol mg-1 protein), involving sites with high affinity (dissociation constant KD = 73 +/- 10 pM). Specific I-CYP binding was displaceable both by beta-adrenoceptor agonists ((-)-isoprenaline greater than (-)-adrenaline greater than (+/-)-fenoterol greater than (-)-noradrenaline greater than (+)-isoprenaline greater than (+/-)-RO363) and antagonists ((+/-)-propranolol greater than ICI-118551 greater than atenolol), indicating a predominance of beta 2-adrenoceptors. Further analysis showed that displacement data for the beta 1-selective antagonist atenolol and the beta 2-selective antagonist ICI-118551 were fitted best to a 2 binding site model and that both beta 1- and beta 2-adrenoceptors were present in pig lung in the ratio 28:72 respectively. Autoradiographic grains were localized over tissue and were most dense over alveolar walls greater than vascular endothelium greater than vascular smooth muscle greater than bronchial smooth muscle = bronchial epithelium. Atenolol (10(-5) M) caused a 31% reduction in specific grain density over alveolar wall tissue, while a 10 fold lower concentration of ICI-118551 (10(-6) M) caused a 50% decrease. These results are consistent with binding data in pig lung parenchyma demonstrating a mixed population of beta-adrenoceptors with a predominance of the beta 2 subtype.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
10.
Improved quality of life after distal splenorenal shunt. A prospective comparison with side-to-side portacaval shunt.
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G Spina R Santambrogio E Opocher F Galeotti G Cucchiaro M Strinna G Pezzuoli 《Annals of surgery》1988,208(1):104-109
The distal splenorenal shunt (DSRS) was compared with the side-to-side portacaval shunt (PCS) in 93 prospectively matched patients with portal hypertension. After 38 months mean follow-up the two shunts had a different incidence of acute encephalopathy (22% in PCS group and 33% in DSRS group) and chronic encephalopathy (35% in PCS group and 17% in DSRS group), but the difference was not statistically significant. However, the only cases of severe and disabling chronic encephalopathy arose after PCS (p = 0.049). Actuarial curves of chronic encephalopathy showed that the maximum rate of encephalopathy (18%) in the DSRS group was reached 27 months after shunt surgery, whereas this value was reached and passed in PCS group only 4 months after shunt. Chronic encephalopathy occurred for a total duration of 20.1 months after PCS and only 11.1 months afer DSRS (p = 0.003) and occupied 46.3% of the follow-p of PCS patients, as contrasted to 18.7% of the follow-up of DSRS patients (p = 0.0001). DSRS is associated with a lower global incidence of chronic HE without severe forms and provides a better quality of life than does a nonselective shunt. 相似文献