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1.
Enzo Ottaviani Antonella Franchini Paolo Fontanili 《Cellular and molecular neurobiology》1992,12(5):455-462
1. Using an immunocytochemical procedure a wide range of immunoreactive vertebrate bioactive peptides (BAPs) has been found in hemocytes of Viviparus ater: bombesin, calcitonin, CCK-8, CCK-39, GH, glucagon, insulin, oxytocin, neurotensin, secretin, serotonin, somatostatin, substance P, vasopressin, and VIP. 2. No immunostaining was observed for antigastrin and antithyroglobulin antibodies. 3. The presence of BAP-like molecules in hemocytes suggests a correlation between hemocyte and APUD cells and is evidence of a relationship between the neuroendocrine and the immune systems. 相似文献
2.
Ottaviani E 《Tissue & cell》1991,23(3):317-324
Lysozyme immunoreactive molecules (irLm) in Planorbarius corneus was demonstrated by an immunocytochemical method in oocytes, the kidney, spreading phagocytic hemocytes (SH), digestive phagocytic cells, and epithelial cells of the stomach and intestine. Three hr after the injection of a variety of bacteria or substances (S. aureus, E. coli, E. coli LPS, latex particles, PBS) a statistically significant increase in irLm serum level was detected by the microELISA method. Twenty-four hr later, this increase was detected only in specimens which had been injected with bacteria. A similar response was observed 14 days later, following a second injection of the above-mentioned substances in the same snails. The results suggest that: 1) irLm appears to be an inducible molecule responding non-specifically to foreign challenge; 2) no anamnestic response is observed for irLm; 3) a relationship exists between irLm and phagocytosis; indeed, irLm have chemotactic activity towards SH; 4) serum irLm probably originates from different sources; in fact, they are released from SH and the kidney. The increase in the serum irLm level is responsible, at least in part, for the lytic attack and death of bacteria, but it is probably also involved in unspecific inflammatory reactions. 相似文献
3.
A M Bolognani Fantin A Franchini E Ottaviani L Benedetti 《Basic and applied histochemistry》1985,29(4):377-387
The effect of lead on ganglia of Viviparus ater were studied by histochemical and histomorphological procedures. The pollution experiment should be considered a "short-time static bioassay" because of its experimental characteristics. There was considerable accumulation of lead in the ganglia as determined by atomic absorbance (A.A.S.). The cytological damage principally affected the neuronal cell bodies which undergo degenerative processes. The most serious cytopathological changes occurred in the following sequence: nuclear damage leading to pyknosis; nucleolar damage until disappearance; changes in Nissl bodies, at times forming a uniform mass. These cytological disorders led to markedly altered protein synthesis. Nerve fibers and neuroglia did not appear affected by lead exposure, even at higher doses. Membrane enzymes, phosphorylase, NADHDH, NADPHDH and SDH activities were decreased, whereas D-LDH, G-6-PDH, G-6-Pase and MAO activities increased. GDH was unchanged. Changes in polar lipid composition were also observed with an increase of phospholipids and a decrease of sulpholipids and cerebrosides. 相似文献
4.
Intensity of photosynthesis and chlorophyll content as related to leaf age inNicotiana Sanderae hort
U r?zně starých list? v listové r??ici 90 a? 110 denních rostlin Nicotiana sanderae hort. byly sledovány rozdály v intensitě ?isté fotosynthesy a v obsahu chlorofylu (a + b). Ke stanovení intensity fotosynthesy bylo pou?ito dvou odli?ných metod, a to váhového stanovení p?ír?stku su?iny podle Barto?e, KubÍna a ?et-lÍka (1960) a gazometrického stanovení infra?erveným analyzátorem CO2. Nejvy??í intensitu fotosynthesy i nejvy??í obsah chlorofylu (vzhledem k plo?e listové) mají mladé, ale ji? dob?e rozvinuté listy, tj. t?etí a? ?tvrté od vrcholu (prvním listem se rozumí list o plo?e asi 20 cm2). Tyto listy nazýváme ?fotosyntheticky dospělými“. Listy nejmlad?í a zejména pak listy star?í mají intensitu fotosynthesy i obsah chlorofylu ni??í; u nejstar?ích list? je intensita fotosynthesy prakticky nulová. Intensita fotosynthesy i obsah chlorofylu se během vývoje mění: jejich momentální rozdíly u list? v genetické spirále jsou z?ejmě shodné s jejich změnami v ontogenesi listu. Pokles intensity fotosynthesy p?i stárnutí list? je rychlej?í ne? pokles obsahu chlorofylu. P?i ur?itém obsahu chlorofylu (tj. asi 2,25 a? 2,45 mg/dm2) klesá intensita ?isté fotosynthesy k nule. Intensita fotosynthesy je v lineárním vztahu k mno?ství chlorofylu (p?i p?epo?tu na plo?nou jednotku), a to nezávisle na poloze listu v genetické spirále. Obě pou?ité metody ke stanovení intensity fotosynthesy poskytly obdobné výsledky. 相似文献
5.
YOSHIKAZU NAKAMURA KIVOKATSU TANABE KOH.JI EGAWA 《The Journal of eukaryotic microbiology》1989,36(1):58S-60S
Pneumocystis carinii is a pathogen which, causes fatal pneumonia in patients with the acquired immune deficiency syndrome (AIDS). To facilitate the basic study of P. carinii , we have analyzed its major surface proteins by both immunochemical and biochemical methods. The major protein components of both cysts and trophozoites are a group of proteins called "P115" with apparent masses of 105–120 kd. It includes 6 isoelcclric variants. A monoclonal antibody raised against cysts recognizes all 6 variants and reacts with epitopes located in the cell wall indicating that P115 is an immunorcactive surface component. The isoelectric variants contain identical or closely related protein components and they are mannose-rich glycoproteins. The isoelectric variation may be due primarily to differences in glycosylation. The majority of sera from humans with diagnosed pneumocystosis that were tested reacted strongly with the P115 proteins. To develop probes for DNA diagnosis and to facilitate molecular studies, a genomic DNA library of P. carinii has been constructed. Some of these clones were used for DNA hybridization analysis of rat and human lungs. 相似文献
6.
溶液培养小麦幼苗转移至含Cd~(2 )的营养液中,根系乙烯产生较快地增加,约在12h达高峰,然后下降;ACC含量亦呈先升后降的趋势。未和Cd~(2 )溶液直接接触的地上部乙烯亦增加,至36h达高峰,此后急剧下降,而ACG和 MAGC含量持续上升。地上部乙烯的增加,主要是由通过根系运往地上部的镉直接作用的结果,不是根部合成ACG运往地上部后再产生的。电镜观察表明,地上部乙烯产生和ACC含量变化的时间进程,可以与镉进入叶细胞内的部位及其对细胞膜和细胞器的影响相联系。 相似文献
7.
固定化虫荧光素酶光纤传感器 总被引:1,自引:0,他引:1
固定化虫荧光素酶光纤传感器蔡谨,王顺光,杨歧生,吉鑫松(浙江大学化工系生化教研室,杭州310027;中国科学院上海生物化学研究所,200031)关键词虫荧光素酶,ATP,固定化酶,光纤生物传感器ATP是生物体内极为重要的能量物质。如何准确快速地定量A... 相似文献
8.
9.
S. Grassi D. Bambagioni F. Ottaviani G. Serafini 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1993,172(4):473-479
The link between stapedius muscle activity and acoustic structure of vocalization was analysed in cocks of age 20–30 to 90–100 days old. The results show that stapedius muscle activation depends on the acoustic structure of vocalization and changes during vocal development. This dependence was observed in spontaneous calls and in vocalizations elicited by stimulating the mesencephalic calling area. In 30-day-old cocks stapedius muscle EMG response is never associated with vocalizations with an acoustic energy content which is always distributed at frequencies higher than 2000 Hz. The coupling between vocalization and stapedius muscle activity begins later, when birds produce vocalizations with acoustic energy shifted towards lower frequencies. Overall, stapedius muscle activity is related to a bird's production of high amplitude low frequencies. These results support the hypothesis that the primary role of the stapedius muscle during normal vocal development is to dampen the amplitude of low frequency energy that reaches the cochlea during vocalization. 相似文献
10.
红细胞抗高血压因子降压作用的进一步研究 总被引:4,自引:0,他引:4
我们曾报道原发性高血压患者(EHS)红细胞抗高血压因子(AHF)具有缓慢而持久的降压作用。本工作表明,AHF对卒中易感型自发性高血压大鼠(SHRsp)还具有快速短暂的降压作用,注射AHF后10—30s,SHRsp收缩压从原水平的26.8±1.7kPa降至20.1±1.5kPa(P<0.001)。正常人和大鼠红细胞AHF的降压作用明显强于EHS和高血压大鼠AHF。此外我们还发现EHS血浆中存在升压物质。以上结果提示,AHF缺乏和升压物质含量相对较高可能是原发性高血压发病的一个重要原因。 相似文献