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991.
Cytochemistry     
L G Koss 《Acta cytologica》1984,28(4):353-355
  相似文献   
992.
993.
A previous experiment (Herzfeld & Taub, 1977) demonstrated that slide projections and explicit suggestions relating to thermal experiences can significantly augment temperature self-regulations training (.5 degrees F, p less than .05). however, the experimental design was thought to result in an underestimate of the magnitude of the effect, since each subject served as his own control and could therefore make use on nonsuggestion training days of material provided on training days. In this experiment, separate groups of subjects either were given feedback combined with the suggestion procedure on each of 8 training days or were given feedback alone. The mean temperature self-regulation of the suggestion group (2.01 degrees F) was significantly better than the self-regulation (.73) of the nonsuggestion group (t test, p less than 0.01), a difference of 1.28 degrees F.  相似文献   
994.
A gelatin-specific protease from the culture media of human pulmonary alveolar macrophages has been partial purified by gel filtration and characterized. The macrophages were obtained by bronchopulmonary lavage from the lungs of disease-free smoking volunteers. The gelatin-specific protease initially requires trypsin activation. After chromatographing the culture media on a Sephadex G-200 column, trypsin is no longer required for activation. The gelatin-specific protease reported here shares many properties of previously reported gelatinases. It is inhibited by EDTA, cysteine, dithiothreitol and serum. It is unaffected by other protease inhibitors: phenylmethylsulfonyl fluoride, tosyllysine chloromethyl ketone and p-chloromercuribenzoate. Of all substrates tested activity was observed only with gelatin. It was inactive toward collagen, elastin and methemoglobin. This enzyme may have a role in the digestion of collagen which has been cleaved by a mammalian collagenase.  相似文献   
995.
Core temperature decreases throughout short-term maximal exercise in heart-failure patients. To investigate possible causes for this unusual response to exercise, we studied core (pulmonary arterial blood), femoral vein, muscle, and skin temperatures in eight patients with severe heart failure who performed maximal upright incremental bicycle exercise to 50 W. A normal group (n = 4) was exercised for comparison. In the heart-failure patients, core temperature was 36.95 +/- 0.37 degrees C at rest, significantly (P less than 0.05) decreased at 25 W of exercise to 36.59 +/- 0.40 degrees C, and at 50 W remained decreased to 36.57 +/- 0.40 degrees C. In comparison, we found that the resting core temperature in the normal subjects was 37.28 +/- 0.34 degrees C, was the same at 25 W (37.29 +/- 0.41 degrees C), and increased significantly (P less than 0.05) to 37.50 +/- 0.32 degrees C at 50 W of exercise. Femoral vein temperature in heart-failure patients (n = 6) was below core temperature throughout exercise to 25 and 50 W (36.22 +/- 0.62 and 36.34 +/- 0.65 degrees C, respectively). Muscle temperature (n = 7) was significantly (P less than 0.05) lower in the heart-failure patients (34.8 +/- 1.1 degrees C) at rest compared with the normal subjects (36.2 +/- 1.0 degrees C). During exercise, muscle temperature increased above core temperature in only four of the heart-failure patients and was significantly (P less than 0.05) lower (36.5 +/- 1.3 degrees C) compared with the normal subjects (38.0 +/- 0.2 degrees C).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
997.
Testes, collected from 11 species of demersal and platform associated pelagic fishes, were examined microscopically for petroleum induced lesions. The fish were taken from 19 oil and gas production platforms and four control sites from the north-central Gulf of Mexico, during two periods, spring and late summer. The status of the spermatogenic cycle at the time specimens were collected correlated well with the known spawning times for the respective species of fish with one exception. Histopathological evaluation revealed acidophilic granular cells, chromatophores, degeneration and focal leucocytic aggregations as the most prominent and abundant conditions in testes, with encapsulated cysts, protozoa and helminths being observed only rarely. No evidence of adverse effects on gonadal morphology was found.  相似文献   
998.
999.
Cocoyam is the second most important staple crop of Cameroon and root rot is a destructive disease of this plant. Pythium myriotylum (Pm), Fusarium solani (Fs), and Rhizoctonia solani (Rs) were isolated from the rhizosphere of root rot affected cocoyams and from the soil of a cocoyam experimental field plot temporarily devoid of same in Mamu, Cameroon. Pm was isolated from the above soil by the cocoyam leaf disc baits. Fs and Rs were also isolated from the same soils by the water dilution method and from the roots of diseased cocoyams but were always associated with mycelial growth of Pm. Pathogenicity of Pm and in combinations with Fs or Rs or Fs + Rs all developed cocoyam root rot disease (CRRD) symptoms on 3– and 7–month old cocoyam plantlets 2–7 days after inoculation. Symptoms included rotted roots and wilting with general chlorosis of inoculated plantlets. No symptoms of CRRD were noted on cocoyam plantlets inoculated with Fs, Rs, Fs + Rs, and distilled water. Results indicated that CRRD is not caused by several pathogens but only by Pm. Pm isolates from the soils and roots of diseased cocoyams and those maintained in the ROTREP laboratory have significantly bigger diameter of mycelial colony growth in 24 h–period at 31 °C on lima bean sucrose agar, V–8 juice sucrose agar, and potato sucrose agar than on potato dextrose agar and 2 % water agar. The cocoyam plantlets were raised axenically from tissue culture of explants in the laboratory.  相似文献   
1000.
Our earlier binding studies of the 22000- and 20000-Mr variants of human growth hormone (somatotropin) to pregnant-rabbit liver and mammary receptors [Closset, Smal, Gomez & Hennen (1983) Biochem. J. 214, 885-892] suggested that the 20000-Mr variant was a lower-affinity analogue of the 22000-Mr molecule. Since the receptor population in these tissues is not fully characterized, we have now investigated the binding of both variants to the well-characterized and highly specific human-growth-hormone receptor of the human lymphocyte IM-9 cell line. The maximum bindability of radioiodinated 22000- and 22000-Mr to IM-9 cells was 60 and 45% respectively. Both hormone variants have essentially the same binding characteristics: slow association (equilibrium reached in 8-10h at 30 degrees C), poor reversibility ('tight binding'), linear Scatchard plot, same specificity as shown by lack of competition by bovine, porcine or equine growth hormones or human growth hormone-(32-46)-(missing in the 20000-Mr variant),-(1-134)- and -(141-191)-peptides. Both unlabelled hormones inhibit binding of both tracers completely, with the 20000-Mr variant being only half as potent as the 22000-Mr one. The apparent affinity is 2.8 X 10(9)M-1 for the 22000-Mr variant and 1.6 X 10(9)M-1 for the 20000-Mr variant. This decreased affinity of the 20000-Mr variant appears to be due to a lower association rate constant. Concentrations (5 ng/ml) of the two variants that occupy about 15% of the total sites induce a marked down-regulation of the receptors after 18h incubation, but the 20000-Mr variant (50% decrease) has a smaller effect than the 22000-Mr variant (75% decrease). Thus the only consequence of the residues-32-46 deletion in the 20000-Mr variant is a lower association rate and affinity for the IM-9 lymphocyte human-growth-hormone receptor. The close binding characteristics of the two forms suggest that the known differences in their insulin-like effects cannot be explained by differences in the nature of their interaction with the human-growth-hormone receptor.  相似文献   
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