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81.
82.
This is a case report of a 13-year-old girl who developed clinical symptoms of primary pulmonary hypertension (PPH). The prognosis is determined by progressive overloading of the right heart. Tissue from both the right and the left atria was examined using immunohistochemical methods. Cardiodilatin/alpha-ANP (atrial natriuretic peptide)-producing myoendocrine cells were analysed. As recent investigations have shown, the atrium and especially the atrial appendages of the heart function as an endocrine organ which is stimulated by pressure and volume overload, and which produces a natriuretic and vasodilatory peptide hormone from myoendocrine cells. In our case we found a general hyperplasia of the myoendocrine cells of the right atrium which is interpreted as a secondary reaction towards an increasing overload. This also means a temporary compensation of the progressive obstruction of the small pulmonary arteries, initiated by vasodilatory heart peptides. These investigations are in agreement with those of other groups who found an increased production of cardiac hormones in atrial overload. In the perinuclear area, electron microscopy shows zones of autophagolysis and the typical specific atrial granules which account for a dysfunction of atrial myoendocrine cells, as seen in other cardiac diseases. Our results may contribute to a better understanding of the pathogenesis of PPH and may help in diagnosis and therapy.  相似文献   
83.
The rate of glucose consumption in cultured epithelium, endothelium, and keratocytes was measured; and the effect of reduced glucose availability on the consumption rate of these three cell lines was delineated. All three cell types exhibited an asymptotic decrease of glucose over time while being incubated in Krebs-Ringers solutions of varying glucose concentrations. At a concentration resembling that of the aqueous, epithelium (EPI), endothelium (ENDO), and keratocytes (K) consumed 6.7, 7.4, and 9.0 micrograms/cm2/hr respectively. Each cell type consumed glucose at a rate that was related to the amount of available glucose. As glucose concentration was reduced from 90 to 30 mg%, which was a 66% reduction in available glucose, the consumption of EPI, ENDO, and K dropped 74%, 61%, and 44% respectively.  相似文献   
84.
The purpose of this study was to determine whether disruption of early social attachment alters the activity of brain biogenic amine systems in rhesus monkeys (Macaca mulatta). Male rhesus monkey infants were deprived of maternal interaction, peer interaction, or both, during the first 22 months of life. Cerebrospinal fluid (CSF) was collected under rigorously controlled conditions approximately every month and assayed for levels of norepinephrine (NE), its major metabolite, and the metabolites of dopamine and serotonin. Mother-Deprived infants had lower levels of CSF NE than Mother-Reared infants. Mother-Deprived infants also failed to develop the same pattern of intercorrelations between compounds and month-to-month stability in levels of neurotransmitter and metabolites in CSF as the Mother-Reared infants. Finally, there were changes in CSF NE levels associated with social separation and social group formation. The brain NE system appears to be sensitive to changes in the social environment. Its level of activity, as reflected in levels of NE in CSF, appears to depend on both the prevailing social environment and the prior rearing environment.  相似文献   
85.
To conduct a formative and pilot impact evaluation of the State Technical Assessment Team (STAT) program, a visitation-based (visitatie) peer assessment program designed to enhance the organizational capacity of state health department injury prevention programs. The formative evaluation was based on observational, record review, and key informant interview data collected during the implementation of the first 7 STAT visits. Pilot impact data were derived from semi-structured interviews with state injury prevention personnel one year after the visit. Formative evaluation identified 6 significant implementation problems in the first visits that were addressed by the program planners, resulting in improvements to the STAT assessment protocol. Impact evaluation revealed that after one year, the 7 state injury prevention programs had acted on 81% of the recommendations received during their STAT visits. All programs reported gains in visibility and credibility within the state health department and increased collaboration and cooperation with other units and agencies. Other significant program advancements were also reported. Specific program standards and review procedures are important to the success of peer assessment programs such as STAT. Early impact evaluation suggests that peer assessment protocols using the visitatie model can lead to gains in organizational capacity.  相似文献   
86.
Krista Kupres  DO    Capt  Usa  MC    Steven E. Rasmussen  MD  MAJ    Usaf  Fs  MC    John G. Albertini  MD  MAJ    Usaf  MC 《Dermatologic surgery》2002,28(5):388-389
BACKGROUND: Low cost, nonsterile examination gloves are used routinely to perform various dermatologic procedures. OBJECTIVE: To evaluate the perforation rate of nonsterile examination gloves in routine dermatologic procedures. METHODS: Three hundred fifty nonsterile latex examination gloves used to perform shave biopsies were evaluated for perforations using an air inflation/water submersion method. Ninety gloves, which were intentionally perforated with a 30-gauge needle, were used as controls to assess our evaluation method. RESULTS: Eight of the 350 gloves were found to have a perforation, which corresponds to a 2.3% perforation rate. Seven of the eight perforations were found in the web space between the second and third finger sleeves, with one being an obvious manufacturing error. All 90 perforations of the control group were correctly identified. CONCLUSION: There appears to be a very low risk of glove perforation when nonsterile examination gloves are used in routine dermatologic procedures.  相似文献   
87.
88.
The organization of sensory afferents in the antennular nerve (AN) of the spiny lobster and the central arborization of the afferents in the lateral and medial antennular neuropils (LAN, MAN) were analyzed by backfilling the AN with biocytin. The MAN receives primarily thick afferents (diameter ≥ 10 μm) with a consistent pattern of arborization from the medial of the three major divisions of the AN. The LAN, in contrast, receives many thin to medium-sized afferents (diameter ≤ 0.3–5 μm), in addition some with diameters ≥ 5 μm, from the lateral and dorsal divisions of the AN. In contrast to the consistent pattern of arborization in the MAN, afferents projecting to the LAN arborize in widely different patterns. Serially arranged, orthogonal side branches that are suggestive of topographical representation of the serially arranged sensilla on the antennule contribute to the stratification of the LAN. Together with existing electrophysiological data, these morphological findings are consistent with the idea that the MAN receives primarily mechanosensory (largely statocyst) input, as previously thought, but that the LAN receives chemosensory as well as mechanosensory input. The chemosensory input to the LAN would represent a novel pathway for processing chemosensory input from the antennule.  相似文献   
89.
90.
This prospective study examined the influence of long-term amiodarone therapy on the parameters of the signal-averaged ECG and their relation to simultaneously derived Holter monitoring data. For this purpose, 23 patients with angiographically confirmed dilated cardiomyopathy or coronary heart disease and high-grade ventricular arrhythmias, in whom an average of four class I antiarrhythmic drugs had proven ineffective, were stabilized on amiodarone. Before the beginning of therapy, as well as after 2 months and, subsequently, every 3 months, a resting ECG, a signal-averaged ECG by Simson's method, and Holter monitoring were performed. Compared to the initial measurement, we found a significant increase in the duration of the total filtered QRS complex from an average of 114 +/- 24 ms to 127 +/- 35 ms, while the change in voltage did not reach the significance level. The incidence of late potentials remained largely constant under amiodarone; 10 patients showed a constant late potential, 12 patients had no late potential, and one patient with coronary heart disease developed a new late potential. In the long-term follow-up, we ascertained a relatively high responder rate under amiodarone between 41% and 81%. No relation could be detected between the results of the signal-averaged ECG and those of 24-h Holter monitoring.  相似文献   
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