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91.
香菇多糖与IL-2合用对肺癌浸润淋巴细胞抗瘤活性的影响 总被引:1,自引:0,他引:1
目的探讨香菇多糖与IL-2合用对肿瘤浸润淋巴细胞(TIL)抗瘤活性的影响。方法将TIL分别置于含IL-2或IL-2加香菇多糖培养液中培养30d,观察TIL的扩增能力、抗瘤活性的变化。结果IL-2加香菇多糖培养的Til平均扩增倍数和抗瘤活性均明显高于IL-2培养的TIL。IL-2加香菇多糖培养的TIL对自体瘤细胞,K562和Raji细胞的最大杀伤活性分别为67.18±14.73%,71.25±15.86%和66.15±15.07%;而单纯IL-2培养的TIL对各种靶细胞的最大杀伤活性分别为43.81±12.17%,50.83±13.56%和45.41±13.76%。两组相比,差异显著(P<0.05)。结论香菇多糖与IL-2合用具有促进TIL扩增,增强其抗瘤活性的作用。 相似文献
92.
目的:了解腰椎间盘同合并腰骶神经背根节(DRG)嵌压的机制。方法:12例腰椎间盘突出患者术中发现:髓核切除后神经根张力仍较大并固定,沿神经根探查发现腰骶神经DRG充血并肿大,直径0.8-1.2cm,平均1.1cm。嵌压物为增生的上关节突和增生肥厚的关节囊韧带。12例病人共探查15个DRG,其中位于椎间孔6例,椎管和椎间孔交界7例,椎间孔外2例同时合并腰神经在椎间孔外嵌压。 相似文献
93.
Objective. Angiotensin-converting enzyme (ACE) plays a key role in the metabolism of angiotensin Ⅱ (AT Ⅱ) and inactivation of bradykinins and tachykinins, which are potent bronchialconstrictors and mediators of inflammation asthma, and ACE is heavily expressed in the lungs. An insertion-deletion (D/I) polymorphism of ACE gene has been shown to be associated with levels of ACE. We investigate whether the polymorphism of ACE gene is associated with asthma and bronchial responsiveness.Methods. A case-control study was carried out in 50 asthmatics, 7 families with at least 2 asthmatic individuals, and 50 healthy subjects. The insertion/deletion (I/D) polymorphism of ACE gene was amplified by polymerase chain reaction (PCR). Methacholine brocho-provocation and pulmonary function tests were performed in all asthmatics. Results. There was an higher gene frequency of DD genotype of ACE gene in asthmatic subjects and families individuals compared with healthy subjects (46%, 53% vs 16%, P<0.05; odd ratio 4.98). Anhigher prevalence of DD genotype of ACE was in patients with bronchial hyperresposiveness (BHR) (67%vs 33%, P<0.05; odd ratio 3.8). Accordingly, the mean values of FEV1% and FEV1/FVC were higher in asthmatics carrying non-DD alleles than patients with DD genotype (73.78% vs 56.56%, P<0.05; 79.19% vs 69.29%, P<0.05, respectively).Conclusion. These results suggested that DD allele of ACE genotype was significantly involved in genetic susceptibility to asthma. DD genotype of ACE might be a risk factor for the degree of airway obstruction, it could also be implicated in pathogenesis of bronchial hyperresponsiveness. 相似文献
94.
目的:米索前列醇预防产后出血的效果。方法:选择1998年8月至1999年7月在我院住院分娩的300例单胎头位孕妇,随机分为米索前列醇组,催产素组,每组150例,米索组在胎儿娩出前,胎头着冠时给产妇直肠内置米前列醇600ug。催产素组在胎儿娩出后产妇臂部肌注催产素20Iu。观察两组产后2h内出血量。结果:产后2h平均出血量米索前列醇组明显低于催产素组,差异有极显性。产后出血发生率米索前列醇组为3. 相似文献
95.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献
96.
James J Rauh Eric Benner Michael E Schnee Daniel Cordova Caleb W Holyoke Michael H Howard Donglin Bai Steven D Buckingham Michael L Hutton Alain Hamon Richard T Roush David B Sattelle 《British journal of pharmacology》1997,121(7):1496-1505
- The radiolabelled bicyclic dinitrile, [3H]-3,3-bis-trifluoromethyl-bicyclo[2.2.1]heptane-2,2-dicarbonitrile ([3H]-BIDN), exhibited, specific binding of high affinity to membranes of the southern corn rootworm (Diabrotica undecimpunctata howardi) and other insects. A variety of γ-aminobutyric acid (GABA) receptor convulsants, including the insecticides heptachlor (IC50, 35±3 nM) and dieldrin (IC50, 93±7 nM), displaced [3H]-BIDN from rootworm membranes. When tested at 100 μM, 1-(4-ethynylphenyl)-4-n-propyl-2,6,7-trioxabicyclo[2.2.2]octane(EBOB), 4-t-butyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-thione (TBPS), 1-phenyl-4-t-butyl-2,6,7-trioxabicyclo[2.2.2]octane (TBOB) and picrotoxin failed to displace 50% of [3H]-BIDN binding to rootworm membranes indicating that the bicyclic dinitrile radioligand probes a site distinct from those identified by other convulsant radioligands.
- Dissociation studies showed that dieldrin, ketoendrin, toxaphene, heptachlor epoxide and α and β endosulphan displace bound [3H]-BIDN from rootworm membranes by a competitive mechanism.
- Rat brain membranes were also shown to possess a population of saturable, specific [3H]-BIDN binding sites, though of lower affinity than in rootworm and with a different pharmacological profile. Of the insecticidal GABAergic convulsants that displaced [3H]-BIDN from rootworm, cockroach (Periplaneta americana) and rat brain membranes, many were more effective in rootworm.
- Functional GABA-gated chloride channels of rootworm nervous system and of cockroach nerve and muscle were blocked by BIDN, whereas cockroach neuronal GABAB receptors were unaffected.
- Expression in Xenopus oocytes of either rat brain mRNA, or cDNA-derived RNA encoding a GABA receptor subunit (Rdl) that is expressed widely in the nervous system of Drosophila melanogaster resulted in functional, homo-oligomeric GABA receptors that were blocked by BIDN. Thus, BIDN probes a novel site on GABA-gated Cl− channels to which a number of insecticidally-active molecules bind.
97.
抗生素在预防胸外科择期手术切口感染中的应用 总被引:28,自引:4,他引:24
目的 探讨抗生素在预防胸外科择期手术切口感染中的合理应用。方法 按Ⅰ、Ⅱ、Ⅲ类切口对635 例胸外科择期手术分组进行抗生素的种类、应用时机、术后疗程等方面切口感染率的统计比较。结果 Ⅰ、Ⅱ、Ⅲ类切口感染率分别为2.56% 、4.39% 、7.54% ;青霉素类、喹诺酮类和头孢菌素类抗生素应用,切口感染率分别为10.05% 、3.23% 、2.83% 。术后抗生素应用疗程,Ⅰ、Ⅱ类切口感染率3 天以上无差异性,Ⅲ类切口感染率5 天以上无差异性。结论 预防性抗生素应用在胸外科择期手术中有确实的临床意义;Ⅱ、Ⅲ类切口的预防性抗生素以二、三代头孢菌素类或三代喹诺酮类为好,Ⅰ类切口的预防性抗生素应用仍应首选青霉素类为宜 相似文献
98.
视频显示终端脉冲磁场对细胞间隙连接通讯功能的影响研究 总被引:1,自引:0,他引:1
目的:研究视频显示终端(VDT)脉冲磁场对细胞间隙连接通讯功能的影响。方法:用15.6kHz、峰值强度为200 μT的脉冲磁场(PMF)和(或)十四酰基咐拜醇酯(TPA:5 ng/m l)对培养的中国仓鼠肺成纤维细胞(CHL)进行辐射24 h,采用离子电渗注射法观察荧光黄向与其接触的周围细胞的传递情况。结果:TPA对细胞间隙连接通讯(GJIC)功能具有抑制作用,与空白对照组相比有显著差异(P< 0.01),单纯VDT组对GJIC无抑制作用(P> 0.05),亦未见该脉冲磁场对TPA的抑制作用有增强效应。结论:视频显示终端脉冲磁场(15.6 kHz)对细胞间隙连接通讯功能无直接和(或)协同TPA的抑制作用 相似文献
99.
目的 :探讨黄色肉芽肿性肾盂肾炎 (XGP)的诊治方法。方法 :分析了 8例XGP的临床资料 ,并就其临床表现、诊断及治疗进行分析讨论。结果 :7例术前误诊或漏诊 ,1例术前诊为XGP ;7例呈弥漫型XGP患者行患肾全切 ,1例呈局限型XGP行肿块剜除术 ,术后疗效好 ,未见复发。结论 :对于有长期尿路感染史以及X线发现某些可疑性改变者 ,CT、DSA以及B超有助于正确诊断。尿沉淀找泡沫细胞和B超引导下细针穿刺活检可以明确诊断。治疗上对弥漫型病变主张肾全切除术 ,局限型主张行肾部分切除或肿块剜除术。 相似文献
100.
采用有机磷化合物对层柱交联累托石催化剂进行了改性研究。考察了有机磷化合物的加入对催化剂轻瓦斯油裂化活性和积炭性能的影响。结果表明:含有适量磷化合物的层柱交联累托催化剂,焦炭产率可降低30%,轻瓦斯油在层柱交联累托石催化剂上的裂化反应和积炭反应是并行的,而裂化活性仍保持不变。磷化合物的加入使层柱交联累托石催化剂的B酸强度增加,但积炭反应主要不是由B酸强度决定,而是与强弱B酸中心数目的比例以及B酸和L 相似文献