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Overall ninety patients with chronic obstructive bronchitis presenting with signs of varying degree cardiopulmonary insufficiency (CPI) were evaluated by radionuclide ventriculography with technetium pertechnetate as well as by rotational viscosimetry of blood. The degree of hemorheological derangements tended to get higher with CPI severity (light, moderately severe, severe) being accompanied by progressing impairement of systolic and diastolic functions of both ventricles of the heart. Mechanisms of compensation of endocardiac hemodynamics were realized as a result of increase in end-diastolic and end-systolic volumes of both ventricles together with changes in amplitude and time characteristics of processes of ventricular ejection and filling. Forecast of the probable course of the condition may rely upon the functional state of right as well as left ventricle of the heart. 相似文献
73.
Previously, we demonstrated elevated cortisol production/release in response to the administration of the serotonin precursor, L-5-hydroxytryptophan (L-5-HTP) in untreated patients with obstructive sleep apnea (OSA). We hypothesized that if this elevated cortisol response to L-5-HTP was related to OSA, this finding would not be present in OSA patients treated with nasal continuous positive airway pressure (nCPAP). Eleven OSA patients treated for at least 1 month with nCPAP were studied. On two different days, we measured blood cortisol level every 15 min for 4 h following the ingestion of L-5-HTP, 0.4 mg/kg, or placebo, both given with carbidopa, a peripheral tryptophan decarboxylase inhibitor, used to prevent peripheral L-5-HTP metabolism before brain absorption. For a given subject, the cortisol response was calculated as the difference between the area under the curve of the L-5-HTP and placebo responses. In the nCPAP-treated OSA patients, this net cortisol response, 577 +/- 240 min.micrograms/dL, was less than the value found in the previously studied untreated OSA group, 1,198 +/- 227 min.micrograms/dL (p < 0.05) and not different from the previously studied nonapneic control group, 469 +/- 154 min.micrograms/dL. From these results, we speculate that nCPAP treatment reverses the elevated cortisol response to serotonergic stimulation seen in untreated OSA patients. 相似文献
74.
Operative treatment of fractures of the femur neck is the method of choice. The authors prefer the A. Seppo construction out of great number of fixtures but it is difficult to introduce and remove this fixture due to its complexity. To make the procedure of such interventions easier the authors propose a marking device, a screwdriver and a device allowing the fixture's curvature to be regulated. The modification of the technique and using a specially developed extractor is explained by difficulties in removing the fixture by common methods. The variant of the improved instrumental tooling proposed by the authors makes the operation more handy and practicable. 相似文献
75.
2H nuclear magnetic resonance (NMR) spectroscopy of choline-deuterolabeled 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC-alpha-d2 and POPC-beta-d2) has been used to detect and quantify domain formation induced in cationic lipid-containing bilayers upon the addition of anionic polyelectrolytes. Three different polyelectrolytes, poly(sodium 4-styrenesulfonate) or PSSS, poly(sodium acrylate) or PACA, and poly(sodium glutamate) or PGLU, were added to POPC lipid bilayers containing 1,2-dioleoyl-3-(dimethylamino)propane (DODAP) as the cationic amphiphile. All three polyelectrolytes produced two-component 2H NMR spectra, consistent with two populations of POPC, one polyelectrolyte-bound and another polyelectrolyte-free. The relative intensities of the two spectral components provided the relative amounts of the two POPC populations. The 2H NMR quadrupolar splitting from either spectral component provided the DODAP content of the particular POPC population. The two POPC populations differed in that the polyelectrolyte-bound population contained a stoichiometric polyelectrolyte anion:DODAP cation ratio leading to enrichment with respect to DODAP, while the polyelectrolyte-free population was depleted of DODAP. Estimates of the size of a polyelectrolyte-defined domain revealed a constant number of bound DODAP but a flexible number of bound POPC, which increased in proportion to the global POPC content. The most compact domains were formed by the most hydrophobic polyelectrolyte, PSSS, while the most expansive domains were formed by the most hydrophilic polyelectrolyte, PGLU. 相似文献
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Foster KL Kimpe LE Brimble SK Liu H Mallory ML Smol JP Macdonald RW Blais JM 《Environmental science & technology》2011,45(23):10053-10060
Seabirds bioaccumulate contaminants from prey, transport them to their nesting sites, and deposit them in their excreta and carcasses, thereby focusing marine-derived contaminants into remote, terrestrial receptor sites. In the case of organochlorine chemicals transported by northern fulmars (Fulmarus glacialis) to a High Arctic seabird colony on Devon Island, Nunavut, Canada (76°13'N, 89°14'W), this contaminant pathway dominates all others. In freshwater ponds below the nesting cliffs, concentrations of organochlorine contaminants characteristic of fulmar input were 2- to 45-fold higher in sediments and water (depending on seabird input to the particular pond) than in ponds remote from the colony. Air-water fugacity quotients for the ponds decreased with seabird input, indicating that fulmar contaminant input shifts air-water partitioning to increasingly favor volatilization to air. Although contaminant evasion from water was favored, direct evidence of it was not detected in air samples. For PCBs, congener profiles of pond sediments or water became more similar to seabird sources as seabird input increased, and less similar to air profiles. Based on measurements of contaminants in fulmars and other local environmental media, this study presents the first application of fugacities and multivariate source apportionment statistics to resolve seabird biological vectors. 相似文献
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Limiting dilution assays to measure the frequency of interleukin-2-secreting peripheral blood T cells were carried out in patients, whose renal allografts had failed due to acute rejection (9 patients) and in patients whose grafts failed more than two years after transplantation without any recent evidence of acute rejection. Using a modified form of the assay we demonstrate that nearly half of 18 patients whose renal transplants had failed after more than two years have low or undetectable HTLp frequencies against donor, but not third-party DR antigens. No such difference was observed in any of the nine patients studied whose transplants were lost from early acute rejection. These results provide the first indication that, as in rodent models of transplantation, T cell unresponsiveness towards donor MHC antigens can occur following prolonged residence of an allograft in humans. Furthermore, the results suggest that chronic rejection may be driven by mechanisms other than direct allorecognition. The assay may be a valuable tool to study the evolution of donor-specific direct T cell alloresponsiveness in patients with well-functioning grafts. 相似文献