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1.
Eileen M. Proctor Judith L. Isaac-Renton William B. Robertson William A. Black 《CMAJ》1985,133(9):876-878
A survey was done of Canadians who had been interned by the Japanese during World War II to assess the prevalence of latent infection with Strongyloides stercoralis in this group. Packages containing three mail-in kits and a questionnaire were sent to 992 men, 694 (70%) of whom responded. Larvae were found in the stool specimens of four of the respondents. Examination of stool specimens after formalin-ether concentration was the most successful method of detecting Strongyloides larvae. The Baermann concentration technique yielded negative results in all four men. Three of the four cases of strongyloidiasis were detected after sampling of three fecal specimens. In the fourth case additional specimens were requested on the basis of data derived from the questionnaire. The most frequently cited clinical manifestations were abdominal pain, weight loss, diarrhea and rashes. 相似文献
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Evolution of the 28S ribosomal RNA gene in anurans: regions of variability and their phylogenetic implications 总被引:1,自引:0,他引:1
Fifteen restriction sites were mapped to the 28S ribosomal RNA gene of
individuals representing 54 species of frogs, two species of salamanders, a
caecilian, and a lungfish. Eight of these sites were present in all species
examined, and two were found in all but one species. Alignment of these
conserved restriction sites revealed, among anuran 28S rRNA genes, five
regions of major length variation that correspond to four of 12 previously
identified divergent domains of this gene. One of the divergent domains
(DD8) consists of two regions of length variation separated by a short
segment that is conserved at least throughout tetrapods. Most of the
insertions, deletions, and restriction-site variations identified in the
28S gene will require sequence-level analysis for a detailed reconstruction
of their history. However, an insertion in DD9 that is coextensive with
frogs in the suborder Neobatrachia, a BstEII site that is limited to
representatives of two leptodactylid subfamilies, and a deletion in DD10
that is found only in three ranoid genera are probably synapomorphies.
相似文献
4.
Characterization of cross-bridge elasticity and kinetics of cross-bridge cycling during force development in single smooth muscle cells 总被引:4,自引:2,他引:2 下载免费PDF全文
Force development in smooth muscle, as in skeletal muscle, is believed to reflect recruitment of force-generating myosin cross-bridges. However, little is known about the events underlying cross-bridge recruitment as the muscle cell approaches peak isometric force and then enters a period of tension maintenance. In the present studies on single smooth muscle cells isolated from the toad (Bufo marinus) stomach muscularis, active muscle stiffness, calculated from the force response to small sinusoidal length changes (0.5% cell length, 250 Hz), was utilized to estimate the relative number of attached cross-bridges. By comparing stiffness during initial force development to stiffness during force redevelopment immediately after a quick release imposed at peak force, we propose that the instantaneous active stiffness of the cell reflects both a linearly elastic cross-bridge element having 1.5 times the compliance of the cross-bridge in frog skeletal muscle and a series elastic component having an exponential length-force relationship. At the onset of force development, the ratio of stiffness to force was 2.5 times greater than at peak isometric force. These data suggest that, upon activation, cross-bridges attach in at least two states (i.e., low-force-producing and high-force-producing) and redistribute to a steady state distribution at peak isometric force. The possibility that the cross-bridge cycling rate was modulated with time was also investigated by analyzing the time course of tension recovery to small, rapid step length changes (0.5% cell length in 2.5 ms) imposed during initial force development, at peak force, and after 15 s of tension maintenance. The rate of tension recovery slowed continuously throughout force development following activation and slowed further as force was maintained. Our results suggest that the kinetics of force production in smooth muscle may involve a redistribution of cross-bridge populations between two attached states and that the average cycling rate of these cross-bridges becomes slower with time during contraction. 相似文献
5.
J H Lustgarten M Proctor R I Haroun A M Avellino A A Pindzola M Kliot 《Journal of biomechanical engineering》1991,113(2):184-188
The regeneration of lesioned axons is critically influenced by the local microenvironment. In this study, semipermeable polymer tubes were used to provide a defined microenvironment in vivo to analyze the regeneration of dorsal root axons under various conditions in the adult rat. Cut dorsal root fibers grew across a 2.7 mm gap within enclosed polymer tubes by 4 weeks. The pattern of axonal outgrowth was dramatically influenced by mechanical factors such as the inner surface topography of the polymer tube. Tubes containing various molecular and cellular substrates were also used to study their effect on dorsal root regeneration. 相似文献
6.
Effect of dose schedule of vitamin E and hydroxethylruticide on intestinal toxicity induced by adriamycin 总被引:1,自引:0,他引:1
J E McGinness B Grossie P H Proctor R S Benjamin O P Gulati J A Hokanson 《Physiological chemistry and physics and medical NMR》1986,18(1):17-24
CDF1 mice receiving Adriamycin, 12 mg/kg IP develop a toxic GI mucositis. The mean survival in CDF1 mice after Adriamycin injection was found to be 6.5 +/- 2.0 weeks and could be increased by alcohol or acetate Vitamin E pretreatment (with 2 g/kg qDx7d) to 22.06 +/- 12.3 weeks or by treatment with Venoruton after Adriamycin (qDx7 with 1.5 g/kg) to 23.7 +/- 12.7 weeks. Other schedules were ineffective or harmful. The ability of Venoruton to enhance survival when given after Adriamycin encouraged us to proceed to tumor bearing mice. The maximum survival with CDF1 mice bearing 5 X 10(6) L1210 cells was 1 +/- 0.2 week which could be increased to 2.17 +/- 0.8 weeks with optimal dose Adriamycin (10 mg/kg). Optimum survival with Venoruton and a single dose of Adriamycin was 2.45 +/- 0.91 weeks with Venoruton, 1.5 g, qd X 14, and 12 mg/kg Adriamycin. Treatment of L1210 bearing mice with Adriamycin, 10 mg/kg on days 1 and 8, yielded a survival of 2.23 +/- 0.7 weeks. An equitoxic regimen of Adriamycin, 11 mg/kg on days 1 and 9, plus Venoruton, 1.5 g, qd X 14, increased survival 30% to 3.08 +/- 2.9 weeks. Venoruton is a promising agent to increase the therapeutic index of Adriamycin. 相似文献
7.
Crystalline inclusion bodies resembling those seen in Clostridium cochlearium were detected in cultures of Bacillus thuringiensis infected with bacteriophage. 相似文献
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9.
No catalase activity was detected in four strains of glucose-grown Mycoplasma pneumoniae at any time during the replication of the organism. Exogenous catalase dramatically increased the O(2) uptake with glycerol, presumably by releasing inhibition caused by hydrogen peroxide. The effect of added catalase on the O(2) uptake of washed organisms with glucose as substrate was moderate and variable in degree. The production of hydrogen peroxide was demonstrated by the quantitative enzymatic assay for inorganic peroxide and by the fact that added pyruvate, which is non-enzymatically oxidized by H(2)O(2) to acetic acid and CO(2) could mimic the action of catalase. 相似文献
10.
Airborne disease and the upper respiratory tract 总被引:2,自引:0,他引:2
D F Proctor 《Bacteriological reviews》1966,30(3):498-513