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81.
Comparisons are made of self-reported medical costs from a sample of headache patients who underwent various combinations of relaxation training and biofeedback training. The average costs for the 2 years prior to self-regulatory treatment were $955±480 (3 SEM) for 45 patients; for the 2 years after completing treatment the average costs were $52±28 (3 SEM) for patients. Within the limitations of the study, medical costs do seem to have been markedly reduced.This research was supported by a grant from NINCDS, NS-15235.  相似文献   
82.
Rapid measurements of plasma creatine kinase activity using an inexpensive benchtop reflectance photometer (Ames Seralyzer) and disposable reagent strips were evaluated in the laboratory and coronary care unit. The system proved simple to use and capable of yielding rapid (four minutes per analysis), precise (coefficient of variation less than 9%), and accurate results (correlation with routine method 0.995) when used by medical staff. Creatine kinase values were available 6.5-102 hours earlier than routine laboratory data, depending on the time and day of sampling, thereby facilitating appropriate and economic patient management. This instrument might be used to supplement the routine enzyme service for selected admissions, resulting in greatly improved availability of results and hence contributing to the early discharge of patients from intensive care facilities.  相似文献   
83.
The general hypothesis that morphological, physiological, and ecological adaptations of macro algal functional-form groups can be related to the level of disturbance encountered in a natural environment was examined. Two articulated calcareous coralline algae (Amphiroa van-bosseae Lemoine, 24% cover and Corallina frondescens Post. & Rupr. 20%) and one non-articulated coralline alga (Lithophyllum sp., 16%), all late-successional predation-tolerant strategists, comprise most of the community cover on stable bedrock substrata at Punta Las Cuevitas, Sonora, Mexico. Conversely, Ulva rigida C. ag. (26% cover) and a ralfsioid crust (23%), shows to be early-successional opportunistic strategists, cover more of the disturbed boulder habitat. Porolithon sonorense Daws., a stress-tolerant strategist, is uniquely abundant on both substratum types (13% cover on boulders, 10% on bedrock). The sheet-like and filamentous algae, prevalent in the temporally unstable habitat, generally show greater productivity (>2×) than the thicker and calcareous forms conspicuous in the more constant environment. It appears that selection for delicate thalli with high productivities, as well as selection for tougher morphologies having lower photosynthetic rates due to greater proportions of structural tissues, are widespread, divergent evolutionary forces among marine algae. Experiments with captive sea urchins (Echinometra vanbrunti Agassiz), in conjunction with fish-preference data published for some of the same algae studied here, offer strong support for the functional-form model. Parrotfishes, rudderfishes, surgeonfishes, damselfishes and E. vanbrunti, in the Gulf of California, preferentially feed on delicate, early-successional, sheet-like, and filamentous algae, while rejecting or ignoring the more structured, late-successional and calcareous algae. There is no significant (P > 0.05) gradation in calorific content between the first four of the six functional groups (i.e., Sheet-, Filamentous-, Coarsely Branched- and Thick Leathery-Groups), but the mean value for these fleshy forms (2.6 kcal · g ash-free dry wt?1) is significantly greater than that for the last two groups (0.3 kcal, Jointed Calcareous- and Crustose-Groups). The approach used in this study demonstrates a realistic technique for predicting macrophyte community composition from knowledge of the disturbance levels in a given habitat or the reverse. The form group-disturbance relationship has important implications for future biological monitoring of rocky-inter-tidal and subtidal systems.  相似文献   
84.
The binding of serum C3 to the O-antigen capsule (OAg Cap), lipopolysaccharide (LPS), and outer membrane proteins (OMP) of Escherichia coli 0111B4 was examined. Bacteria were intrinsically labeled with [3H] or [14C]galactose (*gal) in the OAg Cap and LPS moieties or with [14C]leucine (*leu) to label proteins. Organisms were then incubated in serum containing differentially labeled C3, the above fractions were separated, and the proportion of each binding to a column containing anti-C3 was measured. The OAg Cap fraction bound 72 to 82% of the C3, which bound to E. coli 0111B4 during incubation in absorbed 10% pooled normal human serum (10% PNHS) or absorbed 40% C8-deficient serum (C8D). This distribution did not change when the organism was presensitized with immune IgG before serum incubation. A total of 2.93% +/- 0.48 of OAg Cap and 0.52% +/- 0.16 of LPS *gal bound specifically to Sepharose-containing antibodies to C3 (A:C3-Seph) after incubation in 10% PNHS; these values increased to 10.1% +/- 4.5 and 1.8% +/- 0.3, respectively, when C3 deposition was increased fourfold by incubation in 40% C8D. When encapsulated E. coli 0111B4 was incubated in 10% PNHS containing biotinylated C3, specific attachment of OAg Cap *gal to avidin-Sepharose was demonstrated in 1% sodium dodecyl sulfate (SDS), and complete release of bound *gal but not C3 occurred with 1 M NH2OH. When a mutant of E. coli 0111B4 lacking OAg Cap was incubated in 40% C8D, the outer membrane (OM) bound 85% of C3. Five percent of OM *gal from the unencapsulated organism bound to A:C3-Seph in 0.05% SDS, indicating that the fraction of LPS molecules with bound C3 increased threefold in the absence of OAg Cap. OAg Cap does not contain protein, and no net specific binding of *leu from OAg Cap fractions to A:C3 was detectable; 2.4 to 3.6% of OM *leu bound to A:C3-Seph. Immunoprecipitation of 82.9% of OAg Cap *gal with antisera that were directed to E. coli 0111B4 was associated with co-precipitation of 69.5% of C3 in the capsular fraction. Therefore, the majority of C3 bound to E. coli 0111B4 was covalently attached to OAg Cap and LPS. As corroboration of experiments with whole bacteria, purified OAg Cap and purified LPS consumed C3 when incubated in serum in the fluid phase. These results are the first to evaluate the acceptor site for C3 deposition on a Gram-negative organism incubated in serum, and show that LPS, OAg Cap, and OMP are all major acceptor sites for C3 in nonimmune serum.  相似文献   
85.
Summary Human cancers express organ-specific cancer neoantigens (OSN) as determined by in vitro leukocyte responses to extracts of cancers by the tumor host. In this study, we determined whether the OSNs were normal developmental proteins that were expressed by fetal organs and re-expressed with oncogenesis. Fetal extracts, principally of lung and colon but also of liver and kidney, were tested for their ability to induce leukocyte adherence inhibition (LAI) as compared to extracts from adult tissues of the same organ. Leukocytes from lung cancer patients showed positive LAI responses to 13- and 19-week fetal lung tissue. Likewise, leukocytes from colon cancer patients showed positive LAI responses to 14- and 19-week fetal colon tissue, whereas leukocytes from control subjects did not. Neither group responded positively to 21-week fetal organs. Criss-cross experiments showed that the fetal antigen was organ specific. Multiparous pregnant women showed positive LAI responses to cancer extracts but not to extracts from normal tissues of the same organ. The pattern of the LAI response was bell-shaped. Positive LAI responses to lung and breast cancer were detected at 4 to 7 months gestation and peaked at 5 months. To the fetal colon, LAI positive responses were detected at 5 to 8 months gestation, with the peak response at 6 months. The results indicate that OSN of cancers are also expressed by fetal organs and sufficient antigen is shed by fetal organs to sensitize pregnant women. Older fetal organs (21 weeks) and adult organs do not express an immunogenic or antigenic OSN.Supported by a grant from the National Cancer Institute of Canada  相似文献   
86.
Noxious cutaneous stimulation of anterior sites on Aplysia californica causes withdrawal and turning followed by escape locomotion. Stimulation of anterior sites causes significantly larger turning responses than does stimulation of posterior sites, so that escape locomotion is always directed away from a site of 'attack'. Later phases of escape locomotion are often the same, regardless of the site of the triggering stimulus. The defensive secretions, ink and opaline, are directed along the anterior-posterior axis at the source of noxious stimulation. Ink and opaline ejections are directed to the front or back of the animal by characteristic responses of the siphon, mantle, and parapodia. Ink and opaline are ejected by a series of coordinated pumping movements of the mantle, gill, and parapodia that closely resemble triggered 'respiratory pumping' or 'Interneuron II' episodes (Kupfermann and Kandel 1969; Byrne and Koester 1978; Hening 1982). The directed ejection of secretions from the mantle cavity in response to noxious stimulation suggests a number of potential defensive functions for these secretions including aggressive retaliation, startle display, diversion, and alarm signalling (Edmunds 1975). Taken together, our results and others' suggest an integrated scheme for the functional organization of overt defensive behavior in Aplysia, and begin to suggest testable hypotheses about the integration of defensive responses on the cellular level in this animal.  相似文献   
87.
88.
Polycation binding to the negatively charged surface of chloroplast thylakoid membranes is known to cause an inhibition of photosystem I activity. It also interferes with the cation-dependent rearrangement of chlorophyll proteins in the thylakoid membrane. It was shown that added anions prevented or reversed the inhibition of photosystem I by polylysine without decreasing its binding to the membranes. Anions also caused a change in the interaction of the chlorophyll proteins in polylysine-treated thylakoids as indicated by an increase in the relative fluorescence intensity from photosystem II. In both cases, the relative effectiveness of the anions tested depended on their valence; for example, the tetravalent species Fe(CN)64t- was effective at a concentration at least 2 orders of magnitude lower than the divalent species SO42?. These results suggest that anions act by screening the positive charge of the polylysine-coated membrane surface. Measurements of the response of the anionic fluorescent probe 1-anilinonapthalene-8-sulfonate to an addition of anions to polylysine-treated thylakoids supported this contention. It was concluded that the action of polylysine on photosystem I and on the chlorophyll proteins is mediated by changes of the electrical properties of the thylakoid membrane and may not involve a direct binding of the polycation to the affected membrane proteins.  相似文献   
89.
Association between coated vesicles and microtubules   总被引:3,自引:0,他引:3  
In this study, a possible functional association between microtubules and coated vesicles is described. We have found that our preparations of microtubules contained coated vesicles in quantities of usually above 10%. These coated vesicles were identified both by immunological methods using anticoat antibodies and by electron microscopy of negatively stained specimens. In the immune replica, two components of coated vesicles, i.e., heavy (clathrin) and light chains, were recognized as constituents of the preparations. In the electron microscope, it was found that coated vesicles were attached predominantly along the length of microtubules. Furthermore, projections from the microtubules to the triskelion centers of the clathrin lattice were identified and thus seem to serve as linkers between the cytoskeletal structure of the organelle. A similar type of association was detected in tissue culture cells; bridges between coated vesicles and microtubules were clearly identified by electron microscopy of thin sections.  相似文献   
90.
Long-term changes of sedimentary particle-size distribution in two tropical lowland lakes were compared with changes of human population sizes, estimated archaeologically, in the drainage basins. Mean particle size of silt and clay fractions (<64 µm) varied between 3 and 15 µm. High positive skewness and kurtosis of the distributions were associated with smaller particle sizes; hence small mean size resulted from greater influx of small particles while influx of larger particles was probably constant. An inverse correlation between mean particle size and human population size is interpreted to mean that disturbance-induced erosion results in delivery of very fine inorganic particles at higher rates. Within any one basin, particle-size stratigraphy is more precisely related to archaeological time periods than is pollen stratigraphy. An absolute chronology still eludes us, owing to the failure of 14C dating of calcareous, colluvial sediments, but our relative chronology is now more precise than before. If certain assumptions about past hydrologic relations can be met, particle-size analysis is a way of comparing the histories of geographically very different lakes, including lakes from tropical, temperate, and arctic regions.  相似文献   
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