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31.
Post exercise lymphocytopenia is well documented and attributed to egress of lymphocytes from the vascular compartment. Recent studies have reported exercise induced DNA damage in leukocytes and have questioned a possible link to apoptosis. Eleven subjects underwent a ramped treadmill test to exhaustion. Venous blood samples were taken before, immediately post exercise, and 24 and 48 hours after exercise. Single cell gel electrophoresis revealed evidence of single strand DNA damage in 10% of lymphocytes immediately after exercise, but not at other times. Fluorescent microscopy showed three patterns of DNA distribution, similar to those seen in apoptosis, at all times after exercise. Three subjects underwent the same exercise protocol, and lymphocytes were prepared for flow cytometry to determine apoptosis using the TUNEL method. Flow cytometry revealed lymphocyte apoptosis in 63% of lymphocytes immediately after exercise and 86.2%, 24 hours after exercise. Lymphocyte apoptosis is documented for the first time after exercise and may in part account for exercise induced lymphocytopenia and reduced immunity. 相似文献
32.
Examined the sensory preconditioning (SPC) analogs to UCS and CS intensity in 2 experiments with male hooded rats (N= 144). In Exp. I, Ss received S1-S2 (light and tone, counterbalanced) pairings with 1 of 3 different intensities of S2, followed by conditioned emotional response (CER) training to S2. Suppression of drinking by S1 (SPC groups) and S2 (CER groups) was tested. Amount of SPC was not significantly affected by S2 intensity, but the strength of the CER was an increasing function of S2 (CS) intensity. In Exp. II, amount of SPC was a monotonically increasing function of S1 intensity. Results are interpreted in terms of the similarities and differences between SPC and classical conditioning. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
34.
Comments on E. S. Edgington's (see record 1974-24284-001) tabulation of statistical procedures used in American Psychological Association journals during 1964–1972 and expresses concern that Edgington's suggestions might be taken too literally or be overgeneralized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Conducted discrimination eyelid conditioning at 2 UCS intensities under inhibitory, neutral, and facilitatory instructional sets, in a experiment involving 144 undergraduates in 6 groups. Instructional set yielded receiver operating characteristic curves that were reasonably straight lines on a normal deviate plot. The tentative conclusion from signal-detection theory of an equal discriminability function across instructional sets was contrasted with 4 indices of discrimination, indicating significant but mutually contradictory changes in discrimination as a function of instructional set. Discrimination differences were produced by UCS intensity, particularly under the neutral instructions. (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Identifies sources of error in the analysis of the Social Sciences Citation Index (SSCI) for 1975 conducted by N. S. Endler et al (see record 1979-26949-001). Problems include combining citations of authors with the same names or initials, incorrectly attributing citations, and attributing citations from such sources as research anthologies to the author who edited the compilation rather than the author who wrote the original article. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
The fate of carbon tetrachloride (CT) during phytoremediation with poplar was assessed by examining the transpiration of CT from leaves, diffusion from soil, tree trunks, and surface roots, and accumulation of chloride ion in soil and plant tissues. Feedwater containing 12-15 mg/L CT was added to the field test beds planted with poplar, and over 99% of the CT was removed. No significant amount of CT was transpired or diffused into the air, and no significant amount of CT-chlorine accumulated in the tree tissues. Chloride ion accumulated in the soil accounted for all of the CT-chlorine removed. When soils from the root zones were compared to unvegetated soils, microbial mineralization of CT was not enhanced in soils from the root zones as compared to unvegetated soils. Thus, we conclude that uptake and dechlorination of CT by plant tissues is likely the primary mechanism for phytoremediation by poplar. 相似文献
38.
Examined the generality among schizophrenics of the specific form of associative intrusion identified by L. J. Chapman (1964, 1965, 1971), an exaggerated strong meaning-response bias. Ss were 15 drug-free chronics, 18 medicated chronics, 18 medicated acutes, and 18 normal prisoners matched for education, length of institutionalization (chronic groups and prisoners only), and estimated IQ. As hypothesized, only chronic schizophrenic patients differed significantly from psychiatrically normal prisoners. Expected phenothiazine effects, however, were not observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
We report a practical approach to the positioning of a number of single-mode fibres for endfire coupling to channel waveguides. Boivin's approach has been extended to a flip-chip configuration which permits its use with substrates other than silicon. 相似文献
40.
Electrospray ionization has grown to be one of the most commonly used ionization techniques for mass spectrometry, and efforts continue to improve its performance. Typically, the sprayer tip must be very close to the entrance orifice of the mass spectrometer in order to maximize the conduction of ions from the sprayer into the mass spectrometer. However, because of space-charge repulsion, most ions never reach the sampling orifice. In this work, an industrial air amplifier, for which the working mechanism is based on venturi and coanda effects, was added between an electrospray ionization source and a time-of-flight mass spectrometer. When a series of reserpine solutions (0.5, 1.0, 5.0, and 10.0 microM) were monitored using mass spectrometry, an over 5-fold increase in m/z 609.3 ion intensity was measured for a separation distance of 14 mm between the electrospray tip and interface capillary inlet, as compared to when the electrospray tip was in its normal position 1 mm in front of the inlet without the amplifier. When a voltage was applied to the air amplifier to further assist in focusing the electrosprayed ions, an approximately 18-fold increase in m/z 609.3 ion intensity was obtained. In addition, a 34-fold reduction in method detection limit was observed. 相似文献