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81.
Summary The locomotory turns of the beetle Tenebrio molitor were recorded from free walking animals which were held in stationary position and orientation by means of a tread compensator. Striped patterns revolved around an animal elicit optomotor responses which undergo an inversion at smaller stripe widths. The position of the inversion point characterizes the resolving power of the motion detectors, and corresponds to a 6.5° average angle between the optical axes of interacting elements in the motion detecting device. This indirectly determined value is consistent with the anatomically measured 7° average angle between the axes of neighbouring ommatidia in the Tenebrio compound eye. 相似文献
82.
83.
Georg Heinrich 《Protoplasma》1964,58(3):402-425
Ohne Zusammenfassung 相似文献
84.
Human and chicken erythrocytes are readily coated in vitro by blood group active protein-lipopolysaccharides and lipopolysaccharides from E. coli O86 and E. coli O128. Serum albumin, α2- and β-lipoproteins inhibit this sensitization. Blood group B specific agglutination of erythrocytes with B or B-like antigens was obtained with antibodies purified by adsorption on and elution from B erythrocytes. Anti-blood group B and E. coli O86-specific antibodies could be eluted from E. coli O86-coated O erythrocytes. Eel anti-H(O) serum agglutinated O erythrocytes and only those A1B red cells which were coated with blood group H(O) active E. coli products. Blood group active substances specifically inhibited agglutination of lipopolysaccharide-coated erythrocytes by anti-B and anti-H(O) agglutinins. Demonstrable amounts of lipopolysaccharide could only be removed from coated erythrocytes by washing them at elevated temperatures (58°C) in physiological solutions. Red cell sensitization with B active E. coli O86 substances was achieved in vivo in a minority of severely diseased infants and in germ-free and ordinary chicks which were in tourniquet shock after treatment with cathartics. Therefore, a possible mode by which erythrocytes of patients with severe intestinal disorders acquire antigens is the fixation of bacterial substances to their surfaces, if there are not enough of the normally interfering plasma factors present. 相似文献
85.
Quantum Requirement for Photosynthesis in Chlorophyll-Deficient Plants with Unusual Lamellar Structures 总被引:1,自引:0,他引:1
Neither an over-all deficiency of chlorophyll, nor an increased enzymatic capacity for maximal rates, nor an unusual lamellar structure was found to change the number of quanta required for the evolution of one molecule of oxygen in healthy aurea mutants of tobacco. The average minimal quantum number remains 10 (efficiency 0.1) as in many algae and typical higher plants. Most of the time the optimal efficiency depends on the availability of some far-red radiation, particularly in the blue region of the spectrum where blue light alone is rather inefficient. These results fit an explanation offered earlier in connection with the hydrogen or acetate photometabolism of algae in far-red light. 相似文献
86.
87.
Georg Steinbacher Otto Wettstein Josef Scholze Wolfgang Makatsch Kurt Bauer Harald Duchrow Klaus Warncke Peter Dancker E. Bezzel H. Remold und Helmut Sick 《Journal of Ornithology》1959,100(1):103-112
Ohne Zusammenfassung 相似文献
88.
89.
K. Lynette Pearce Dr. Bernard T. Engel John R. Burton 《Applied psychophysiology and biofeedback》1989,14(3):207-217
Fifteen hypertensive patients were recruited from a geriatric medicine clinic for a research project designed to evaluate a Behavioral Stepped-Care treatment program of high blood pressure (HBP). All patients met the selection criteria of the Isolated Systolic Hypertension (ISH) in the Elderly (SHEP) clinical trial. During baseline, subjects recorded BP at home 9 times/day (3 times each, shortly after awakening, during the middle of the day, and within an hour of retiring) for 1 month and mailed that data to us daily. In addition, they came to the clinic weekly and had their BP recorded by a nurse. During treatment 1, systolic (SBP) feedback, they were trained to lower SBP at home using their sphygmomanometers. They also continued to monitor BP and to obtain weekly professional BP readings. During treatment 2 (relaxation), they were trained to relax; they followed the self-administration and data-collection protocol as in treatment 1. Each treatment phase lasted 3 months. Average monthly self-determined BP fell significantly from 166.4/85.8 (SBP/DBP) mm Hg during baseline to 153.3/81.2 by the end of the relaxation phase; average monthly professionally measured BP fell significantly, from 164.7/87.1 to 156.9/81.5. These findings show that a nurse-supervised, patient-administered behavioral treatment program of ISH can yield sustained, significant falls in BP.Ms. Pearce and Dr. Burton were supported in part by the Johns Hopkins Academic Nursing Home Award, PO, AG04402, from the National Institute on Aging. This material was presented in part at the annual meeting of the Gerontological Society of America, November 1988, San Francisco. 相似文献
90.
We studied the changes in functional residual capacity (FRC), thoracoabdominal volume (Vw), and chest wall configuration in five normal subjects seated in an aircraft flying parabolic trajectories resulting in 20-s periods of microgravity. We measured vital capacity (VC), inspiratory capacity, and tidal volume by integrating airflow at the mouth and changes in rib cage and abdominal volume (delta Vrc and delta Vab, respectively, where delta Vrc + delta Vab = delta Vw) using induction plethysmography. During microgravity (0 Gz) FRC decreased by 413 +/- 70 (SE) ml and VC by 0.37 liter. The decrease in Vw did not differ from that in FRC and was entirely the result of reduction of Vab, the Vrc showing no significant change. During tidal breathing the abdominal contribution (delta Vab/delta Vw) increased from 0.39 +/- 0.08 at 1 Gz to 0.57 +/- 0.08 at 0 Gz. During brief periods of hypergravity (approximately 1.8 Gz) all changes were opposite in sign and relatively smaller. Limited data during "roller coaster" flight patterns suggested that, in contrast to configurational changes, the temporal pattern of breathing was uninfluenced by changes in Gz. We conclude that at the onset of weightlessness there are substantial changes in lung volume and thoracoabdominal configuration. Abdominal contribution to tidal excursions increases but the temporal pattern of breathing is unchanged. 相似文献