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71.
We have established 950 and 430 oligoclonal B-lymphoblastoid cell lines (LCL) from two normal persons and eight autoimmune disease patients, respectively by using Epstein-Barr virus (EBV)-induced transformation. To re-evaluate the EBV technique for production of human monoclonal antibodies (mAb) related to infectious disease, we screened these oligoclonal LCLs for antibodies against 31 bacterial strains systematically. A total of 74 cultures out of 1380 were reactive to a total of 18 strains out of 31. Among these, eight cultures showed 10-3 antibody (Ab) titers to Pseudomonas aeruginosa serotypes C, E, F and I, Staphylococcus aureus, Serratia marcescens and Bacillus cereus. Ten cultures showed 10-2 Ab titers to Ps. aeruginosa serotypes D, E, F and I, Ps. maltophilia, Staph, epidermidis, Klebsiella ozaenae, Ser. marcescens and B. subtilis. The results reveal the further possibilities for the EBV technique to produce various infectious disease-related human mAbs.  相似文献   
72.
An immunohistochemical and immunoelectron microscopic study was used to demonstrate tyrosine hydroxylase (TH) and dopamine -hydroxylase (DBH) immunoreactivities in the rat pancreas. Small TH immunoreactive cells were found in close contact with large TH immunonegative ganglion cells among the exocrine glands and were occasionally found in some islets. Some of these TH immunoreactive cells were also DBH immunopositive. The immunoreaction product was seen diffusely in the cytoplasm and in the granule cores of TH immunoreactive cells. All intra-pancreatic ganglion cells were immunoreactive for DBH, but not for TH. The TH immunoreactive cells were identified as small intensely fluorescent (SIF) cells due to their localization and morphological characteristics and showed no insulin, glucagon, somatostatin or pancreatic polypeptide immunoreactivities. These results indicate that SIF cells may release dopamine or noradrenaline to adequate stimuli while the intra-pancreatic ganglion cells with only DBH may not synthesize catecholamines in a normal biosynthetic pathway. TH immunoreactive nerve bundles without varicosities and fibers with varicosities, associated or unassociated with blood vessels, were found in both the exocrine and endocrine pancreas. Close apposition of TH immunoreactive nerve fibers to the smooth muscle and endothelial cells of the blood vessels was observed. A close apposition between TH immunoreactive nerve fibers and exocrine acinar cells and islet endocrine cells was sometimes found in the pancreas. The immunoreaction product was seen diffusely in the axoplasm and in the granular vesicles of the immunoreactive nerve fibers. Since no TH immunoreactive ganglion cells were present in the rat pancreas, the present study suggests that noradrenergic nerve fibers in the pancreas may be extrinsic in origin, and may exert an effect on the regulation of blood flow and on the secretory acitivity of the acinar cells, duct cells and endocrine cells.  相似文献   
73.
The food habits of the Iriomote catFelis iriomotensis were studied by analyzing 177 feces collected monthly from 1987 to 1988. A total of 26 food items were identified. The frequency of lizards and frogs in the feces was higher than those of mammals and birds. The food habits changed greatly seasonally.Eumeces skinks were fed on most frequently, and found in the feces with a similar high frequency occurrence in March–April and July–September, while their proportion to the total number of food items was larger in March–April than in July–September. The cats fed on larg-sized skinks, adultEumeces kishinouyei, more in March–April than in other seasons. The number of skinks sighted in the course of a road census was greater from March to August, and large-sized skinks were sighted more in March–April than in July–August. The cats fed selectively on large-sized skinks in every season. Therefore, changes in the food habits depended on the food availability. Characteristics of food habits in the Iriomote cat are discussed in comparison with the food habits of other felids in temperate and tropical regions.  相似文献   
74.
The flowering response of axillary buds of seedlings of Pharbitis nil Choisy, cv. Violet, was examined in relation to the timing of apical bud removal (plumule including the first leaf or second leaf) before or after a flower-inductive 16-h dark period. When the apical bud was removed well before the dark period, flower buds formed on the axillary shoots that subsequently developed, but when removed just before, or after, the dark period, different results were observed depending on the timing of the apical bud removal and plant age. In the case of 8-day-old seedlings, fewer flower buds formed on the axillary shoots developing from the cotyledonary node when plumules were removed 20 to 0 h before the dark period. When the apical bud was removed after the dark period, no flower buds formed. Using 14-day-old seedlings a similar reduction of flowering response was observed on the axillary shoots developing from the first leaf node when the apical bud was removed just after the dark period. To further elucidate the relationship between apical dominance and flowering, kinetin or IAA was applied to axillary buds or the cut site where the apical bud was located. Both chemicals influenced flowering, probably by modulating apical dominance which normally forces axillary buds to be dormant.  相似文献   
75.
A [beta]-glucuronidase (GUS) gene that is under the control of the anther-specific LAT52 promoter of tomato (Lycopersicon esculentum) and the nopaline synthetase polyadenylation terminator was successfully expressed in pollen of Lilium longiflorum, Nicotiana tabacum, Nicotiana rustica, and Paeonia lactiflora using a pneumatic particle gun. The GUS gene in plasmid pBI221 was also expressed, to a lesser extent, in pollen of all of these species. The presence of methanol in the substrate solution for histochemical GUS assay and the incubation time in this solution influenced successful detection of GUS expression in bombarded pollen. Cytological analysis of GUS-expressing pollen of lily showed that introduced gold particles were seen in intracellular compartments of pollen, including the vegetative cytoplasm, vegetative nucleus, and generative cytoplasm.  相似文献   
76.
Aplopsora corni sp. nov. is proposed for a rust fungus whose uredinial and basidial stage occurs onCornus controversa (Cornaceae) in Hokkaido. This new species is separated by its larger urediniospores and probasidia from the morphologically closely relatedA. nyssae onNyssa aquatica andN. sylvatica (Cornaceae) distributed in southern North America.  相似文献   
77.
A mutant of human immunodeficiency virus type 1 which carries a frameshift insertion in the integrase/endonuclease region of pol gene was constructed in vitro. Upon transfection into cells, although this mutant exhibited a normal phenotype with respect to expression of gag, pol, and env genes and to generation of progeny virions, no replication-competent virus in CD4-positive cells emerged. An assay for the single-step replication of a defective viral genome dependent on trans complementation by rev protein was established and used to monitor the early phase of viral infection process. Viral clones with a mutation in the vif, vpr, or vpu gene displayed no abnormality in the early phase. In contrast, the integrase mutant did not direct a marker gene expression after infection. Together with an observation that the mutant lacked the ability to integrate, these results indicated that the integration was required for efficient viral gene expression and productive infection of human immunodeficiency virus type 1.  相似文献   
78.
To determine whether lipid-secreting cells have cytosolic Ca2+ concentration ([Ca2+]c)-related secretory mechanisms, morphological changes and intracellular calcium dynamics of Harderian glands of guinea pigs stimulated by secretagogs were studied by electron microspy and Fura-2/AM digital image analysis. Control glandular cells contained large lipid vacuoles that were bordered by multi-layered membranes. Rough-surfaced endoplasmic reticulum, mitochondria, and smooth-surfaced endoplasmic reticulum may be involved in lipid vacuole formation. Myoepithelial cells surrounded alveoli. After carbamylcholine (CCh, 10–6, 10–5, and 10–3 M) stimulation, lipid materials within the membranous structures were frequently discharged by an exocytotic mechanism. Conspicuous deformation of glandular cells caused by vigorous contraction of myoepithelial cells was observed in isolated alveoli after 10–6M CCh stimulation, whereas the deformaties of glandular tissues perfused via vessels were small even after 10–3M CCh stimulation. Connective tissue between glandular alveoli inhibited unbridled myoepithelial-cell contraction. Fura-2/AM digital imaging analysis revealed that CCh stimulation caused an increase in [Ca2+]c in isolated alveoli. The morphological reactions and changes in [Ca2+]c were prevented by atropine. When extracellular calcium ions were absent, enhanced extrusion of lipid vacuoles, myoepithelial-cell contraction, and a rise in [Ca2+]c after CCh stimulation were not observed. Nicotine and catecholamines had no effect on the secretion or on the dynamics of [Ca2+]c. It can be concluded that acetylcholine elicits exocytosis in glandular cells and contraction of the myoepithelial cells of Harderian glands, accompanied by an increase in [Ca2+]c. The dynamics of [Ca2+]c of the gland alveoli are mostly dependent on extracellular Ca2+.  相似文献   
79.
Using cultured cells of the hornwortAnthoceros punctatus, the change in the relative chloroplast DNA content in each stage of chloroplast division was investigated to clarify the relationship between the division cycle of a chloroplast and a cell nucleus. Samples of cultured cells were stained with 4′,6-diamidino-2-phenylindole (DAPI) and then observed with an epifluorescence microscope and a chromosome image analyzing system (CHIAS). A chloropiast in cultured cells duplicated DNA with an increase in size. When a chloroplast began to divide, it was constricted in the middle, taking a dumbbell shape, and then divided into two daughter chloroplasts. In cultured cells of this species, the pattern of quantitative change of chloroplast DNA, that is, the DNA replication pattern of chloroplasts, corresponded to that of cell nuclear DNA in mitosis.  相似文献   
80.
T Ono  N Ogawa  A Mori 《Regulatory peptides》1989,25(2):215-222
The effects of hemorrhagic shock on thyrotropin-releasing hormone (TRH) levels and its receptors were studied in different regions of the rat brain. Rats were bled for 30 min from the left femoral artery, and their mean arterial pressure was kept at 40 mmHg for the following hour. The rats were killed by decapitation. Rat brains were immediately removed and dissected into 7 regions. Hemorrhagic shock decreased TRH significantly in the frontal cortex, septum, hippocampus, and hindbrain but TRH was not changed in the striatum, hypothalamus, and midbrain. Hemorrhagic shock significantly decreased TRH receptor binding in the septum and hindbrain. Scatchard analysis of saturation isotherms of specific TRH binding showed that the decreased specific TRH binding in the hindbrain resulted not from an increase of the dissociation constant (Kd), but from a decrease in the maximum number of binding sites (Bmax). In the septum, the decrease in specific binding was due both to a decrease in Bmax and an increase in Kd. The findings indicate that TRH plays a role in the physiological response to hemorrhagic shock.  相似文献   
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