Enhanced antitumor effects of tumor antigen-pulsed dendritic cells by their transfection with GM-CSF gene

To investigate the biological characterization and antitumor activitites of GM-CSF gene-transfected dendritic cells, the splenic dendritic cells were infected with GM-CSF recombinant replication-deficient adenoviruses in vitro . Their enhanced expression of B7 was demonstrated by FACS analysis, and more potent stimulatory activity was confirmed by allogeneic MLR. Immunization of dendritic cells pulsed with irradiated B16 melanoma cells induced sig-nificant CTL and enabled host to resist the challenge of wild-type B16 cells. When they were transfected with GM-CSF gene subsequently, the induced CTL activity was higher, and the produced protection against B16 cell challenge and therapeutic effect on the mice with preestablished pulmonary melastases more effective. These data suggest that the dendritic cells pulsed with tumor antigen then transfected with GM-CSF gene can be used as an effective vaccine in tumor immunotherapy.     

马尾松毛虫雄蛾触角毛状感受器的细微结构

马尾松毛虫Dendrolimus punctagus(Walker)雄蛾有一对羽毛状触角。在触角鞭节的每对侧枝的内侧(迎风面)着生许多毛状感受器。每个毛状感受器由几丁质表皮毛及位于其下的三个感觉神经原和三个呈同心排列的辅助细胞-鞘原细胞、毛原细胞和膜原细胞构成。几丁质表皮毛上有许多孔。毛腔内充满感受器淋巴液。感觉神经原发出的树状突伸入毛腔,浸浴于感受器淋巴液内。这些结构特征表明它是一种司嗅觉的化学感受器。雄蛾终生不取食,推断它的嗅觉感受器主要用以感受雌蛾释放的性外激素,帮助寻找配偶。     

四川省鱼类寄生粘孢子虫两新种（粘孢子纲：双壳目）

本四川省鱼类寄生粘孢子虫两新种：寄生墨头鱼的宜宾两极虫,新种Ｍｙｘｉｄｉｕｍ ｙｉｂｉｎｅｎｓｅ ｓｐ．ｎｏｖ．和寄生鳙Ａｒｉｓｔｉｃｈｔｈｙｓ ｎｋｂｉｌｉｓ的鳙单尾虫,新种Ｕｎｉｃａｕｄａ ａｒｉｓｔｉｃｈｔｈｙｄｉｓ ｓｐ．ｎｏｖ。     

东海黑潮锋面涡旋区浮游动物的分布

本文根据中日黑潮合作调查研究,１９８９年４月航次在东海北部黑潮及其邻近海域采集的浮游生物样品,分析黑潮锋面涡旋区饵料浮游动物的分布特点及其与海洋环境的关系。首次报道了在东海黑潮锋面涡的冷中心区发现冷水性桡足类,从而丰富了调查区浮游动物区系的冷水种成分,并为锋面涡涌升水的研究和黑潮潜流的研究提供了生物学证据。     

丁酸钠和pH值对离体蚕豆花药中小孢子有丝分裂的影响

含单核中后期至后期花粉的蚕豆离体花药,经过2mM丁酸钠24小时预处理后,再漂浮培养于pH5.8或7.0的液体培养基。以不经预处理的作为对照。结果如下: 1.培养后9天内,丁酸钠预处理和培养基pH值并不明显影响花粉退化百分率。2.培养初期,pH7.0显著促进小孢子不等分裂。3.丁酸钠预处理抑制培养初期的小孢子有丝分裂,而后又显著增加小孢子均等分裂百分率。4.丁酸钠预处理导致小孢子有丝分裂类型的趋向改变。本文还对丁酸钠导致有丝分裂类型趋向改变的可能原因,进行了讨论。     

家兔晶状体纤维的超微结构:纤维细胞的间隙连接

本文报道晶状体纤维细胞间间隙连接的形态结构。我们利用冰冻断裂技术,在不同部位的球-和-凹连结的头部以及在纤维细胞和纤维细胞之间都观察到间隙连接的存在。通过极其丰富的上述连接,可实现细胞间代谢物和离子的传递。作者认为:对正常晶状体纤维细胞之间的间隙连接的深入了解,将会为晶状体发病机制的研究提供新的线索。     

猫尾核头部前区对三叉神经尾端脊束核的抑制作用及其方式

在清醒麻痹状态下的55只猫上,观察了电刺激尾核头部前区(Cd)对三叉神经尾端脊束核(cST)中了齿槽神经(AI)伤害性刺激所诱发的放电的影响。刺激 Cd 可以抑制大多数 cST 神经元的伤害性反应,抑制持续约100—500ms。抑制时程可为静脉注射戊巴比妥钠和安定而延长,注射印防己毒素可使其缩短。马钱子素使抑制时程稍有延长。这些结果提示,Cd 对 cST神经元的抑制作用是通过突触前抑制的方式实现的。     

人工补充寄主卵对松林内卵蜂种群消长的影响

在不同生境的松林中,人工补充寄主卵都能提高寄生效果。但林地生境不同,寄生率有明显差异。在松阔混交林中补充寄主,其寄生率比对照提高5.5—16.2倍。植被稀疏的纯松林效果较差,补充的寄生率比对照提高3.0倍。 卵蜂种群消长随季节温度而变化,全年以5月中旬至6月下旬和9月中旬至10月中旬为两个寄生高峰。卵蜂种群与松毛虫种群的消长存在较明显的相依关系,卵蜂种群随着松毛虫种群的消长而消长。施药对卵蜂种群有较大影响,施药区比对照区的寄生率约降低一倍。在混交林中填充寄主卵,能促进卵蜂种群世代延续。在逐步改善林地生境的基础上,利用人工补充寄主,可以代替人工繁蜂放蜂。     

现代化经济建设与生态科学——试论当代生态学工作者的任务

宇宙空间是无限的,但适于人类生活和生物生存的生物圈则是有限的,它是个松散结构的大系统,其中包括许多类型的生物集团与无机环境结合而成的功能单元,即生态系统。在长期进化过程中,通过物质循环与能量交换,生物圈与生态系统之间建立了相互协调与补偿关系,并使生物圈及生态系统都具有一定限度的调节功能。人类对自然界的依存关系,以及自然界所形成的生态平衡是长期演化而形成的,人类亦参与和适应了此平衡过程。维持这种平衡的基础是有规律的物质循环和能量交換。此种质能流动则是通过     

Transients in toad skin: Short circuit current and ionic fluxes related to inner sodium substitution by monovalent cations

Summary When the Na electrochemical potential difference across the skin (_Na) is altered by perturbing the transmembrane electrical potential difference or the external Na concentration, effects on transport and associated oxygen consumption can be described by the formalism of linear nonequilibrium thermodynamics (Vieira, Caplan & Essig, 1972,J. Gen. Physiol. 59:77; Danisi & Lacaz-Vieira, 1974,J. Gen. Physiol. 64:372; Procópio and Lacaz-Vieira, 1977,J. Membrane Biol. 35:219). We now show that with modifications of _Na by substitution of Li or choline for Na in the inner bathing solution, this formalism is no longer applicable. Inner Na by K substitution ((Na×K) _i ) causes profound alterations in short-circuit current (SCC),J _Na ⁱⁿ , K efflux (J _K ^eff ) and PD. SCC drops transiently after (Na×K) _i in Cl and in SO₄ media, increasing subsequently. In Cl medium, following the initial transient, there is a late decline in SCC toward a steady state. The rate of SCC decline in Cl medium is more pronounced than that observed in SO₄ medium. (Na×K) _i causes a transient increase inJ _Na ⁱⁿ with a peak synchronous to the minimum in SCC, both in Cl and in SO₄ media. This was interpreted as due to depolarization of the inner membrane. In SO₄ medium, following the peak observed after (Na×K) _i J _Na ⁱⁿ drops, to increase again toward a steady state in which SCC andJ _Na ⁱⁿ are not statistically different, resembling the control condition before (Na×K) _i . In Cl medium, however, theJ _Na ⁱⁿ steady state is approximately 100% higher than SCC. This difference is due to an important K efflux (J _K ^eff ), which builds up progressively after the substitution. The apparent K permeability [J _K ^eff /(K _i )] is of comparable magnitude in Cl and in SO₄ media before (Na×K) _i , the apparent K permeability increases one order of magnitude as compared to the control condition before the ionic substitution. In Cl medium, the high levels ofJ _Na ⁱⁿ and ofJ _K ^eff observed in the steady state after (Na×K) _i were interpreted as being a consequence of cell swelling. SCC and PD follow very different temporal patterns after (Na×K) _i which are characterized by transients in SCC and a simple fall in PD. Reasons for these differences are discussed.