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991.
The Protein Journal - The amino acid sequences of the tetracycline-resistance (Tcr) determinants of Bacillus subtilis plasmid pNS1981 and Staphylococcus aureus plasmid pTP5 have been deduced from...  相似文献   
992.
This study was performed in order to identify the fungi of four species (Aspergillus fumigatus, Fusarium anthophilum, Candida albicans, Cryptococcus neoformans) in formalin-fixed, paraffin-embedded tissue sections by the indirect method of immunoperoxidase staining. Mature albino rabbits were immunized by formalin-killed organisms. The antibodies were prepared by precipitation at a 50% saturation of ammonium sulfate and were checked for cross-reactivities by Ouchterlony's double immunodiffusion and precipitin test. The immunoperoxidase staining was applied to the paraffin-embedded tissue sections of infected mice, human autopsy and biopsy specimens. Although each fungus was stained clearly the cell wall, cross-reactivities appeared among them, however it was possible to identify four fungi by absorption and dilution of the antisera.  相似文献   
993.
The expression of a number of enzymes involved in drug metabolism, membrane function etc. was compared in hyperplastic and neoplastic lesions of the rat bladder and in human bladder tumours. Transitional cell carcinomas (TCC) in both rat and Man were characterized by decreased alkaline phosphatase (ALP) and increased gammaglutamyl transpeptidase (GGT), β-glucuronidase (β-Gl), succinate dehydrogenase (SD) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, binding for antibodies specific for different cytochrome P-450 species (UT50, PB3a, MC1, MC2) and microsomal epoxide hydrolase (mEHb) was elevated in both murine and human tumours. Comparison of the enzyme phenotype in hyperplastic lesions induced by freeze ulceration or uracil administration with that in preneoplastic papillary or nodular hyperplasia (PNH) and TCC suggested, however, that most of the alteration in enzyme content or activity was non-specific and related to requirements for epithelial cell proliferation. On the other hand, the decreased ALP, and increased GGT and β - Gl activity appeared more directly related to neoplastic transformation. The results suggested that qualitative differences exist between reactive hyperplasia and preneoplastic or neoplastic lesions in the urinary bladder. The finding of increased cytochrome P-450, in clear contrast to the reduction characteristic of preneoplastic hepatic lesions, may be important with regard to the observed difference in neoplastic transformation between the bladder and liver in response to drug metabolising enzyme inducers. Supported by Grants-in-aid for Cancer Research and a Comprehensive 10 Year Strategy for Cancer Control from the Ministry of Health and Welfare, for Cancer Research and Scientific Research from the Ministry of Education, Science and Culture, and by a grant from the Deutsche Forschungsgemeinschaft  相似文献   
994.
Abstract The chemotaxonomic characteristics of Arthrobacter radiotolerans were investigated. The species possesses a peptidoglycan based on l -lysine (variation A3α) and a DNA base composition of 67.9 mol% G + C. The cellular fatty acids were primarily of the methyl branched types with 12-methyl-hexadecanoic acid as the predominant component. The major isoprenoid quinone was menaquinone with eight isoprene units and the polar lipids consisted of four phospholipids, one phosphoglycolipid and one glycolipid. On the basis of chemical characteristics it is suggested that Arthrobacter radiotolerans be reclassified in a new genus Rubrobacter , as Rubrobacter radiotolerans comb. nov.  相似文献   
995.
An examination of Drosophila melanogaster from natural populations revealed genetic variation for dipeptidase-A (DIP-A) and dipeptidase-B (DIP-B) activities within sets of lines that differed from one another only in the second or the third chromosome. Analyses of diallel crosses indicate that both activities are inherited additively, and coordinate control of expression is suggested by the significant positive correlation between the two activities. Electrophoresis and thermal denaturation studies failed to detect structural differences among lines with different levels of DIP-A activity. No characteristic level of activity could be associated with any DIP-A allozyme. Mapping experiments revealed the presence of activity modifiers that are in tight linkage with the structural gene, as well as those that manifest their effects from a distance. The maximum genetic distance between a high-activity effect on DIP-A and the structural gene was determined to be 0.029 map unit. These results are in accordance with the prevalence of activity modifiers for various enzymes in Drosophila melanogaster.  相似文献   
996.
1. To elucidate the neural mechanisms that mediate visual responses of optic tectum (OT) to medullary and spinal motor systems, we analyzed medullary reticular neurons in paralyzed Japanese toads (Bufo japonicus). We examined their responses to electrical stimulation of OT, and stained some neurons intracellularly. Responses to stimulation of the glossopharyngeal nerve (IX) were also analyzed. 2. Extracellular single unit recording revealed excitatory responses of medullary neurons to OT and IX stimulation. Among 92 units encountered, 79 responded to OT stimuli, 10 to IX stimuli, and 3 to both. Some units responded to successive stimuli of short intervals with relatively stable lags. 3. Intracellular recording and staining experiments revealed morphologies of reticular neurons that received excitatory inputs from OT. Thirteen units were identified after complete reconstruction of somata and dendrites. Neurons in the nucleus reticularis medius received excitatory inputs from bilateral OT. They had wide dendrites in ventral, ventrolateral and lateral funiculi, and single axons descending in the ipsilateral ventral funiculus as far caudally as the cervical spinal cord. Some collaterals of these axons projected directly to the hypoglossal and spinal motor nuclei. Some neurons in other medullary nuclei (nuc. reticularis superior, pretrigeminal nucleus, nuc. reticularis inferior, and nuc. tractus spinalis nervi trigemini) also responded to the OT stimulation. 4. Activities in bilateral OT converge onto medullary reticular neurons, which may directly control medullary and spinal motor systems.  相似文献   
997.
Summary In order to describe precisely the fixed action patterns of salmon sexual behavior, we recorded the electromyographic (EMG) activities of trunk and jaw muscles from freely behaving male and female Himé salmon (landlocked sockeye salmon,Oncorhynchus nerka). A series of action patterns (quivering and spawning act in males, digging, covering, prespawning act and spawning act in females, and the swimming and turning movements in both sexes) were characterized by rhythmic activities of the trunk muscles. Each of these activity patterns is quantitatively distinct from the others in such parameters as frequency, bout duration, duty value, intersegmental phase delay, and spatial distribution of rhythmic activities. However, all of these rhythms share a qualitatively homologous pattern with the forward swimming movement: rhythmic activities alternate on both sides of the body (bilateral coupling) and are posteriorly propagated (intersegmental coupling). In addition, a 31 intersegmental phase coupling occurs in the most anterior trunk muscles during the spawning act in some males. Based on these observations, we discussed the biomechanics for these motor patterns (oviposition, ejaculation, body vibration, and mouth opening), and the neural mechanisms for the pattern generation. A possibility was pointed out that the locomotor pattern generator in the spinal cord may be modulated by descending supraspinal signals and recruited to generate such diverse forms of action patterns in sexual behavior.Abbreviations CPG central pattern generator - EMG electromyography - AC adductor mandibulae (cephalic portion) - AM adductor mandibulae (mandibular portion) - DO dilator operculi - GH geniohyoideus - LAP levator arcus palatitni - LPe musculus lateralis profundus (epaxial portion) - LPh musculus lateralis profundus (hypaxial portion) - LS musculus lateralis superficialis - PD protractor dorsalis - PI protractor ischii - RD retractor dorsalis - RI retractor ischii  相似文献   
998.
Scleral fibroblasts of the chick embryo were found to secrete autocrine growth factors. One of the factors was purified from conditioned medium collected from growing-phase cultures of these cells by DEAE-Sepharose column chromatography and following non-denaturing polyacrylamide gel electrophoresis. The specific activity was increased 1100-fold by this purification. The chromatographically purified growth factor was still active after incubation at 95 degrees C, at pH 10 or pH 3, or with glycosidase H, but inactive after incubation with dithiothreitol or trypsin. An active protein having a molecular weight of 32 kDa was found to be the major component of the final preparation.  相似文献   
999.
Membrane preparation from the bacteriochlorophyll-containing cells of a facultative methylotroph, Protaminobacter ruber strain NR-1, contained reaction center bacteriochlorophyll similar to those in many species of purple bacteria and contained a few cytochrome species. -Peak of the reduced-minus-oxidized difference spectrum of one of the cytochromes was at 554 nm. The midpoint potential of the cytochrome at pH 7 (Em7) was 350 mV. Two other cytochromes had the same reduced-minus-oxidized difference spectra with a split -band at 557 and 566 nm, but had two different Em7s' of 130 mV and 0 mV.On flash or continuous light the reaction center bacteriochlorophyll and the cytochrome with -peak at 554 nm were reversibly oxidized. Redox titration of the light-induced cytochrome oxidation gave an Em7 value of 356 mV. Under continuous illumination the membrane preparation reversibly took up protons, and formed ATP in the presence of ADP and inorganic phosphate. The ATP formation activity on the bacteriochlorophyll basis was one-third to one-fifth that in chromatophores from Rhodospirillum rubrum under similar experimental conditions. These results clearly indicated that the membrane preparation from P. ruber which contained bacteriochlorophyll had a cyclic photosynthetic electron transfer system and coupled ATP formation activity.Abbreviations Bchl (only in figure legends) bacteriochlorophyll - CCCP carbonylcyanide-m-chlorophenylhydrazone - Eh the ambient redox potential - Em7 the midpoint potential at pH 7 - PMS N-methylphenazonium methosulfate - MES morpholinoethanesulfonic acid - MOPS morpholinopropanesulfonic acid  相似文献   
1000.
Three squirrel monkeys, trained to make a requesting gesture, were tested in the presence of a human assistant whose visual attention varied across trials. When food was available in one dish and an empty dish was nearby, the monkeys pointed overwhelmingly toward the former, regardless of where the assistant was looking. Looking at the assistant while pointing (“monitoring”) peaked when she looked at them and when she attempted to engage them in joint attention. When only one dish was present, the monkeys refrained from gesturing if it was empty and if no assistant was present. They gestured more when the assistant made eye contact with them. Furthermore, when the assistant's focus of attention switched from the dish or the ceiling to the monkeys, the latter resumed pointing and increased their monitoring of the assistant. This is the first demonstration of such flexible use of an intentionally communicative requesting gesture in New World monkeys. Am. J. Primatol. 72:707–714, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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