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1.
本文报导五加科一新属,人参本属Chengiopanax Shang et J.Y.Huang,新组合2种,即华人参木Ch.fargesii(Franch.)Shang et J.Y.Hung及人参木Ch.sciadophylloides(Franch.et Sav.)Shang et J.Y.Huang。  相似文献   

2.
安徽金腰属 (虎耳草科)植物新资料   总被引:2,自引:0,他引:2  
楔叶金腰为金腰属一新变种,同时报道安徽新记录种肾萼金腰,并对安徽金腰属植物进行了补充记述。  相似文献   

3.
A new variety Chrysosplenium japonicum var. cuneifolium from Anhui, China, is described, and the species Chrysosplenium delavayi is found new to Anhui. The genusChrysosplenium L. of Anhui is additionally recounted.  相似文献   

4.
本文记述采自四川和安徽的管巢蛛科红螯蛛属蜘蛛一新种——拟邻红螯蛛Chiracanthium adjacensoides sp.nov.。本新种与邻红螯蛛Ch.adjacens Cambridge虽近似,但有明显区别。  相似文献   

5.
本文研究了低毒性的紫色杆菌内毒素对小鼠 CFU-GM 的动员作用,并对其作用机制作了初步探讨。小鼠周围血中 CFU-GM 数随着静脉注射内毒素量的增加而升高。高峰出现在注射后的第三天,为对照组的2.1倍。同时骨髓 CFU-GM 数逐渐下降。脾脏不影响内毒素的动员作用。但在去除肾上腺的小鼠身上,内毒素失去动员作用。结果表明紫色杆菌内毒素是一种比较安全、有效的干细胞动员剂。其动员机制很可能是通过肾上腺或皮质类固醇激素的介导而产生作用。  相似文献   

6.
ld,so we present the well logging series and gas drilling technique suited to Daqing area.Some proper logging evaluation approaches are used such as GR spectrometry log,CN log,induction log and NMR log,etc.well logging;technology;gas drilling;foam drilling;casing drilling;Daqing oilfield0测井技术Well Logging Technology20-22 104P631.8B019;B021;A011;A012;C;21;D3;A;B;B019_21;A011_D3;A012_C;B021_21;赵平;16-18 100高孔密复合射孔技术研究周志华;谭忠健;刘富奎;西安通源石油科技股份有限公司,中海石油(中国)有限公司天津分公司勘探部,中海石油(中国)有限公司天津分公司勘探部 陕西西安710065,天津300452,天津300452复合射孔;;高孔密;;p-t过程测试;;现场应用提出了一种新型装药结构并实现在高孔密条件下的复合射孔,所开发的产品进行了地面混凝土靶测试、地面动态压力-时间(p-t)过程测试和现场应用试验。试验结果表明,高孔密复合射孔器能够将高孔密的多孔道、多相位的射孔特点与高能气体压裂造缝机理有机地结合,形成了孔缝结合的深穿透、高孔密和多相位的沟通通道,有效地改善了近井带的渗流能力,实现了油井的高产和稳产。现场应用效果良好。On High Foramen Density Technology for the Fracture Perfo  相似文献   

7.
AM真菌和施磷量对不同叶位烟叶生长和化学成分的交互效应   总被引:15,自引:0,他引:15  
采用土培试验研究了不同施P水平下接种AM真菌摩西球囊霉(Glomus mosseae)和苏格兰球囊霉(Glomus caledonium)对烤烟不同叶位烟叶生长和化学成分的影响,结果表明,接种AM真菌提高了烟草根系菌根侵染率,增加了烟叶总干重,其中对下位和上位烟叶效果明显,中位叶因菌种而异,接种G.mosseae显著提高了中位叶总糖,烟碱,P,K含量和上位叶K含量,而接种G.caledonium则提高了下位叶总糖和上位叶总糖,还原糖,烟碱含量,促进了上,下位烟叶P含量的增加,烟叶N,Mg,Fe,Zn含量因菌种和施P量不同而变化,施P量为0.056-0.112g/kg^-1土时接种效果最好。  相似文献   

8.
Abstract

Three widely documented mechanisms of chloride transport across plasma membranes are anion-coupled antiport, sodium-coupled symport, and an electrochemical coupling process. No direct genetic evidence has yet been provided for primary active chloride transport despite numerous reports of cellular Cl-stimulated adenosine triphos-phate (ATP)ases coexisting in the same tissue with uphill chloride transport that could not be accounted for by the three common chloride transport processes. Ch-stimulated ATPases are a common property of practically all biological cells, with the major location being of mitochondrial origin. It also appears that plasma membranes are sites of Cl–stimulated ATPase activity. Recent studies of Cl'-stimulated ATPase activity and chloride transport in the same membrane system, including liposomes, suggest a mediation by the ATPase in net movement of chloride up its electrochemical gradient across plasma membranes. Further studies, especially from a molecular biological perspective, are required to confirm a direct transport role to plasma membrane-localized Ch-stimulated ATPases.  相似文献   

9.
Summary Peptide antibodies raised in rabbits are widely used in biology and medicine. During immunization of the animals, the respective antibodies may affect the endocrine cells physiologically responsible for the synthesis of peptides used as antigens. Since corresponding morphological data are still sparse, the rabbit endocrine pancreas was systematically investigated by light microscopy and immunocytochemistry after long-term immunization against glucagon and somatostatin. Both immunizations led to an increase in the number of islets (nesidioblastosis), to the development of giant islets (macronesia), and to changes in the relative proportions of the major types of endocrine cells or their hormonal content. The latter changes differed after either immunization: glucagon immunization resulted in hypertrophy and hyperplasia of glucagon cells and a decrease in their hormonal content; somatostatin immunization led to an increased proportion of somatostatin cells and a lowered hormonal content of insulin cells. The various alterations were expressed differently according to islet type; islets of the rabbit pancreas differ in size or angioarchitecture, and in the proportion and distribution of endocrine cells. The present findings point to autocrine or paracrine effects of the respective peptides. These effects, however, are obviously of differing significance in morphologically heterogeneous islets.Dedicated to Professor Dr. Tsuneo Fujita, Niigata University, JapanPresented in part at the 30th Symposium of the Deutsche Gesellschaft für Endokrinologie (see Jörns et al. 1986)  相似文献   

10.
An active or passive immunization against hormones and the subsequent neutralization of hormones by circulating antibodies is a valuable tool for the identification of hormonal action. To recognize presumed local (autocrine, paracrine) effects exerted by pancreatic hormones, the endocrine pancreas of rabbits was investigated electron-microscopically after long-term immunization against glucagon or somatostatin. Glucagon immunization resulted in hyperplasia and hypertrophy of glucagon- (A-) cells and in their increased metabolic activities: They showed prominent nucleoli, increased amounts of endoplasmic reticulum, Golgi areas, and mitochondria. These changes were paralleled by alterations in secretion granules (increased size, decreased hormonal content), increased numbers of lysosomes (crinophagic bodies), and an increment of the filamentous system. Basically, these findings point to an autocrine regulation of A-cells. Following somatostatin immunization, somatostatin- (D-) cells were hyperplastic but unchanged in their metabolic state. Instead, insulin-(B-) cells and A-cells exhibited equivalents of increased cellular activities (parameters, see above). This stimulation most probably is caused by cancelled paracrine (inhibitory) effects of somatostatin. The changes observed after both immunizations were differently expressed in morphologically heterogeneous islet types (size, angioarchitecture, cellular composition, microtopology of the various cell types). It is concluded, therefore, that the regulation of islets is not uniform. Autocrine and paracrine effects exerted by islet hormones are of different significance in individual islets, or they interfere differently with other regulatory signals.  相似文献   

11.
我国黄胸鼠的研究现状   总被引:20,自引:0,他引:20  
全面综述了对黄胸鼠(Rattus flavipectus)的研究进展。①黄胸鼠是我国三大家栖鼠种之一,体型中等,属东洋界种类。在我国已由主要栖息长江流域及其以南地区扩展到广大的北方地区,并在北方部分地区种群数量不断上升。发达的交通是其由南方扩展至北方的重要途径,全球变暖为其在北方种群增长提供了条件。在南方部分地区,黄胸鼠的优势地位则被其他鼠所取代。住房结构的改变使黄胸鼠适生环境改变,是其种群下降的  相似文献   

12.
Ch14.18 manufactured in Chinese hamster ovary (CHO) cells is currently being evaluated in clinical trials. Short-term infusion (STI) (8–20 h/day; 4–5 days) of 100 mg/m2 ch14.18/CHO (dinutiximab β) per cycle in combination with cytokines is standard treatment of neuroblastoma (NB) patients. As pain is a limiting factor, we investigated a novel delivery method by continuous long-term infusion (LTI) of 100 mg/m2 over 10 days. 53 NB patients were treated with 5–6 cycles of 6 × 106 IU/m2 subcutaneous interleukin-2 (d 1-5, 8-12), LTI of 100 mg/m2 ch14.18/CHO (d 8-18) and 160 mg/m2 oral 13-cis-retinoic acid (d 22-35). Human anti-chimeric antibody (HACA), antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity were determined. With LTI, we observed a maximum concentration of ch14.18/CHO (Cmax) of 12.56 ± 0.68 µg/ml and a terminal half-life time (t1/2 β) of 32.7 ± 16.2 d. The clearance values for LTI and STI of 0.54 ± 0.13 and 0.41 ± 0.29 L/d m2 and area under the serum concentration-time curve (AUC) values of 189.6 ± 41.4 and 284.8 ± 156.8 µg×d/ml, respectively, were not significantly different. Importantly, we detected ch14.18/CHO trough concentration of ≥ 1 µg/ml at time points preceding subsequent antibody infusions after cycle 1, allowing a persistent activation of antibody effector mechanisms over the entire treatment period of 6 months. HACA responses were observed in 10/53 (19%) patients, similar to STI (21%), indicating LTI had no effect on the immunogenicity of ch14.18/CHO. In conclusion, LTI of ch14.18/CHO induced effector mechanisms over the entire treatment period, and may therefore emerge as the preferred delivery method of anti-GD2 immunotherapy to NB patients.  相似文献   

13.
抽薹期叶绿素缺乏油菜突变体类囊体膜的研究   总被引:10,自引:0,他引:10  
以抽薹期野生型油菜和黄化突变体叶片为材料,分析了叶片和类囊体膜的不合色素组成、色素与蛋白相对含量;比较了类囊体膜光谱特性(室温吸收光谱、荧光光谱和圆二色谱);用温和电泳、SDS-PAGE分析了类囊体色素蛋白和多肽组成。结果显示:与野生型相比,突变体叶片的蛋白质含量不变,而Chaa和Chlb的含量均减少;突变体类囊体膜的Chla/Chlb比值较高,Chl/蛋白质比值较低,LHCⅡ色素蛋白复合物的单体和三聚体含量明显减少。突变体的天线系统相对较小、捕光效率较低。  相似文献   

14.
The reactivity of sonicated phosphatidylcholine-cholesterol liposomes with cholesterol : oxygene oxydoreductase, an enzyme which catalyses the oxidation of the 3 beta hydroxyl group of cholesterol to a ketone group, is compared with that of ternary system phosphatidylcholine-cholesterol-Thesit. Regardless to the phosphatidylcholines nature and the phosphatidylcholine/cholesterol molar ratio (R), the enzymatic oxidation rate of liposomal cholesterol is slower than when the reaction is developed in the present of Thesit, a surfactif agent which destroyes the lamellar particles. This is true whether Thesit is added during preparation of dispersions or during incubation with cholesterol oxydase. The enzymatic oxydation rate of cholesterol of ternary systems phosphatidylcholine-cholesterol-Thesit is independent of the (R) value and the phosphatidylcholine fatty acid unsaturation, whereas that of phosphatidylcholine-cholesterol dispersions depends on these two parameters. The reaction rate increases in the order: dipalmitoylphosphatidylcholine to yolk egg phosphatidylcholines, and dioleylphosphatidylcholine. The optimal conditions for cholesterol oxidation were found to be R = 0.5. This result is not affected by the phosphatidylcholines nature. In order to explain these data, various hypotheses are considered. In particular, the weak liposomal cholesterol reactivity with cholesterol oxidase could result from an inhibitory effect on the enzyme-substrate combination due to the polar phosphorylcholine groups.  相似文献   

15.
Cell cycle parameters and expression of myoblast and myocyte antigens were investigated during exponential growth and during the differentiation phase of rat L8( E63 ) myoblasts by an integrated approach involving microspectrophotometry with DNA fluorochromes, [3H]thymidine autoradiography, and immunofluorescent staining with monoclonal antibodies. In addition to the majority of cells which are recruited into myotubes, two distinct populations of mononucleate cells were resolved in cultures of rat myoblasts undergoing differentiation. These mononucleate cells consist of (1) a population of proliferating cells with a prolonged G1 transit time; (2) a population of non-proliferating cells which remain arrested in G1 for more than 72 h. The latter group was examined with respect to the expression of two marker antigens recognized by two monoclonal antibodies: antibody B58 reacts with a macromolecular component present in undifferentiated myoblasts but not in mature myotubes, and antibody XMlb reacts with a muscle-specific isoform of myosin. All four possible combinations of expression of these antigens by single cells were found: B58 +XM1b -, B58 +XM1b +, B58 - XM1b -, and B58 - XMlb +. The implication of these findings with respect to the transition from the proliferative to the differentiative phase of myogenesis is discussed.  相似文献   

16.
In vitro and in vivo studies with adriamycin liposomes   总被引:2,自引:0,他引:2  
Liposome entrapped adriamycin retains its full cytotoxic potential when tested under invitro conditions against murine leukemia L-1210 cells. Invivo drug distribution studies indicate that, relative to the free drug, a lower proportion of adriamycin administered in the liposome form is delivered to the heart and kidneys at one and four hours after injection. When administered to normal mice in high doses, anionic adriamycin liposomes appear less harmful than equal doses of the free drug as judged by alterations in animal weight gain. In these studies, a noval double packing procedure has been used for the entrapment of adriamycin in phospholipid vesicles.  相似文献   

17.
We report and discuss Raman spectra of bacteriochlorophyll a and of bacteriopheophytin a obtained in vitro by resonance effect in their QX and Soret electronic bands. Selective excitation of spectra of either of these molecules in reaction centers of Rhodopseudomonas spheroides, strains Y and R 26, was achieved by illumination in their respective QX bands. Preliminary interpretation of the spectra yields information about the interactions assumed by these molecules in the reaction centers. Spheroidene bound to reaction centers of strain Y probably affects a conformation different from that assumed by the bulk spheroidene of the chromatophore.  相似文献   

18.
New necrotic isolates of Pepino mosaic virus (PepMV) were found in 2007 infecting greenhouse tomato plants in Poland. The isolates differ from previously identified PepMV isolates in host range and symptomatology. They induce severe necrosis on tomato plants ( Solanum lycopersicum ) and local necrotic lesions on Datura inoxia . Phylogenetic analysis, based on three distinct regions, triple gene block 1, the coat protein gene and a part of polymerase gene, revealed that the new necrotic isolates share high nucleotide sequence identity with isolates of the Ch2 genotype. This is the first report describing a necrotic type of PepMV of the Ch2 genotype.  相似文献   

19.
20.
The frequency of the loss of pereiopods and the features of their regeneration were studied in males of the tanner crabs Chionoecetes bairdi and Ch. opilio, sampled in the Sea of Okhotsk in 2001. It was established that after the loss of an appendage a complete recovering of body symmetry in both crab species occurs in four moltings, during which the length of the regenerating pereiopod averages respectively 39–41, 70.5, 89.5, and 96–97% of the norm. The patterns of limb regeneration were compared between tanner crabs and representatives of fam. Lithodidae.  相似文献   

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