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141.
This report summarizes our clinical experience in which the effects of both thalamic sensory relay nucleus (TSRN) and periaqueductal gray (PAG) stimulation were tested in the same series of patients with various forms of pain. The clinical data indicated that neurogenic pain due to deafferentation at the level of the peripheral nerves or the spinal cord was often controlled by TSRN stimulation but not by PAG stimulation. We also review the results of our experimental investigations in cats which were undertaken in an attempt to clarify the neurophysiologic basis of such differential clinical effects of TSRN and PAG stimulation. It appeared that abnormal hyperactivity within the trigeminal medullary dorsal horn following retrogasserian rhizotomy was far more frequently inhibited by TSRN stimulation than by PAG stimulation.  相似文献   
142.
The amount and isomeric composition of urinary biliverdin in rabbits were analysed by h.p.l.c. Physiological values were maintained after the injection of haemin. On the other hand, when haemoglobins from several mammalian species were injected into rabbits, the excretion of biliverdin-IX alpha and biliverdin-IX beta were increased 6-18-fold and 32-66-fold respectively over physiological excretion. Injection of myoglobin resulted in a 44-fold increase in excretion of the IX alpha-isomer. Coupled oxidation with ascorbate of haemoglobin and myoglobin by oxygen produced mainly the IX alpha- and IX beta-isomers from haemoglobin and the IX alpha-isomer from myoglobin. The destruction of part of the haem from injected haemoproteins by non-enzymic chemical degradation would account for the observed respective increases in the excretion of biliverdin isomers. The excretion of biliverdin isomers after the injection of phenylhydrazine into rabbits was similar to that after the injection of haemoglobin.  相似文献   
143.
Isolation and characterization of a genomic DDD mouse interleukin-3 gene   总被引:1,自引:0,他引:1  
K Todokoro  A Yamamoto  H Amanuma  Y Ikawa 《Gene》1985,39(1):103-107
  相似文献   
144.
To investigate the protective ability of monoclonal antibodies (MCAs) to viral glycoprotein in herpes simplex virus (HSV) infection, athymic nude mice were inoculated intracutaneously with HSV type-1 (HSV-1) in the midflank. Three hours after inoculation, one group of mice was passively immunized with one of a series of MCAs to glycoprotein gB of HSV-1, and a control group of mice was given phosphate buffered saline alone. The control mice died within 16 days after infection, whereas the mice passively immunized with any of the MCA showed suppressed development of skin lesions. Three of six mice given MCA failed to develop any visible lesions and no HSV could be isolated from the lumbar dorsal root ganglia of these mice 60 days after the challenge. BALB/c mice were also protected from infection with HSV type 2 by passive immunization with MCA to HSV-1 gB.  相似文献   
145.
We present an algorithm for prediction of RNA secondary structures.The program consists of three parts: the first computes locationand free energy of every possible stem–loop structure,the second computes probability of its formation, and the thirdlists the positions and free energies of all the stem–loopsin the order of their probability sizes. The circular RNA moleculeof chrysanthemum stunt viroid was used as an input data fordemonstrating the operation of the program. Received on March 14, 1985; accepted on March 18, 1985  相似文献   
146.
Specimens of a new genus and species of the stichaeid fish,Leptostichaeus pumilus, were collected from the Okhotsk Sea off Hokkaido in Japan. The present new genus and species clearly differs from all the other genera and species of the stichaeid fishes in the following characters: 3 or 4 pectoral fin rays; 10 or fewer caudal principal rays; 79–82 dorsal spines; no pelvic fin; last interneural spine supporting a single dorsal spine; infraorbital, occipital and lateral line canals absent; moderate size of dorsal spine shorter than eye diameter; membranes of dorsal and anal fins widely connected with caudal fin; a large black spot divided by a yellow band present just above gill cover.  相似文献   
147.
D aft , M.J., B urnham , J.C. & Y amamoto , Y. 1985. Lysis of Phormidium luridum by Myxococcus fulvus in continuous flow cultures. Journal of Applied Bacteriology 59 , 73–80.
In two chemostat systems Myxococcus fulvus (strain BGO2) adhered to the glass walls of the growth vessel and on glass beads contained in a vertical glass column. The bacterium produced long colonial strands that extended towards the centre of the vessel. Both systems allowed measurement of lytic enzyme production and cyanobacterial predatory efficiency. Lysozyme activity produced by the myxococci was dependent on the concentration of the tryptone and the flow rate of the medium. Continuous lysis of Phormidium luridum occurred in both methods of culture in the presence of M. fulvus (strain BGO2). The results suggest that the adhesive characteristics of this bacterium prevent the achievement of steady state kinetics in either saprophytic or parasitic modes of growth. M. fulvus , with its various morphological growth forms and effectiveness in lysing cyanobacteria, is considered to be a potential control agent of cyanobacteria.  相似文献   
148.
149.
Summary The internalization and intracellular movements of apical-cell-membrane material were investigated in the endodermal cells of cultured visceral yolk-sacs of rats (whole-embryo culture; explanted at 10.5 days of gestation and cultured for 24h) using horseradish peroxidase- and ferritin-labelled concanavalin A (Con-A HRP, Con-A Fer). When visceral yolk-sac endoderm was exposed to Con-A HRP or Con-A Fer for 5 min at 4°C, the apical cell membranes containing a well-developed fuzzy coat were heavily labelled, whereas apical vacuoles, lysosomes and apical canaliculi were not. Incubation of Con-A-labelled endoderm for 5 60 min at 20° and 37°C in Con-A-free serum resulted in a temperature-dependent internalization of membranebound lectin into coated vesicles, apical vacuoles and lysosomes, and the apical cell membranes were cleared of the heavy labelling. With increasing incubation time, the number of labelled vacuolar structures and the intensity of their labelling decreased gradually, whereas the number of labelled apical canaliculi increased. Thus, after 30 and 60 min at 37°C, most of the apical canaliculi contained high concentrations of the markers. It was possible to observe labelled apical canaliculi that were in continuity with labelled apical vacuoles and lysosomes as well as with the apical cell membrane. These findings in rat endodermal cells indicate that constitutents of the apical cell membrane are internalized in apical vacuoles and lysosomes, and are then brought back to the apical cell membrane by the apical canaliculi, which concentrate and store this membrane material.Supported by the Deutsche Forschungsgemeinschaft (SFB 105)  相似文献   
150.
Hypoxic and hypercapnic ventilatory responses were measured after two levels of acute inhalation of cigarette smoke, minimum-level nicotine smoke (smoke 1) and nicotine-containing smoke (smoke 2), in 10 normal men. Chemosensitivity to hypoxia and hypercapnia was assessed both in terms of slope factors for ventilation-alveolar PO2 curve (A) and ventilation-alveolar PCO2 line (S) and of absolute levels of minute ventilation (VE) at hypoxia or hypercapnia. Ventilatory response to hypoxia and absolute level of VE at hypoxia significantly increased from 23.5 +/- 22.6 (SD) to 38.6 +/- 31.3 l . min-1 . Torr and from 10.6 +/- 2.5 to 12.6 +/- 3.5 l . min-1, respectively, during inhalation of cigarette smoke 2 (P less than 0.05). Inhalation of cigarette smoke 2 tended to increase the ventilatory response to hypercapnia, and the absolute level of VE at hypercapnia rose from 1.42 +/- 0.75 to 1.65 +/- 0.58 l . min-1 . Torr-1 and from 23.7 +/- 4.9 to 25.5 +/- 5.9 l . min-1, respectively, but these changes did not attain significant levels. Cigarette smoke 2 inhalation induced an increase in heart rate from 64.7 +/- 5.7 to 66.4 +/- 6.3 beats . min-1 (P less than 0.05) during room air breathing, whereas resting ventilation and specific airway conductance did not change significantly. On the other hand, acute inhalation of cigarette smoke 1 changed none of these variables. These results indicate that hypoxic chemosensitivity is augmented after cigarette smoke and that nicotine is presumed to act on peripheral chemoreceptors.  相似文献   
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