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31.
J.P. Newnham C.L. Marshall J.F. Padbury R.W. Lam C.J. Hobel D.A. Fisher 《American journal of obstetrics and gynecology》1984,149(8):888-893
Neurosympathetic system activity at birth was studied by measuring umbilical arterial plasma catecholamine concentrations in 36 preterm fetuses. Umbilical arterial catecholamine concentrations were correlated with blood gas status, mode of delivery, fetal sex, and fetal heart rate patterns. Significant correlations were observed for plasma norepinephrine and epinephrine versus fetal pH and Po2 and for plasma dopamine versus pH but not Po2. These catecholamine relationships to acidosis and hypoxia were similar to those of our previously published data for term fetuses. Norepinephrine and dopamine concentrations were similar in both preterm and term fetuses; however, epinephrine levels were significantly greater in preterm fetuses than in term fetuses. Increased concentrations of norepinephrine, epinephrine, and dopamine were observed in association with abnormal fetal heart rate patterns. These was no significant effect of fetal sex on the catecholamine secretory response. Similar cord catecholamine concentrations were observed following vaginal and cesarean section delivery, the latter with and without labor. These results indicate that the preterm fetus, like the term fetus, responds to stress at delivery with a graded catecholamine release. The observation of greater epinephrine concentrations in preterm fetuses than in term fetuses may reflect either increased secretion or decreased clearance of epinephrine. 相似文献
32.
Aarne I. Oikarinen Riitta Palatsi Gerald E. Adomian Heljä Oikarinen Joan G. Clark Jouni Uitto 《Journal of the American Academy of Dermatology》1984,11(1):64-72
Three patients with localized cutaneous lesions characteristic of anetoderma were studied. Clinically, the onset of the disease was between the ages of 17 and 25, and numerous flaccid, saclike skin lesions developed over several subsequent years. Histologically, the lesions were characterized by paucity and fragmentation of the elastic fibers. Electron microscopy demonstrated that the elastic fibers, both in papillary and deep reticular dermis in the lesional skin, were fragmented and irregular in appearance. The concentration of elastin, determined by a radioimmunoassay of desmosine, an elastin-specific cross-link compound, was markedly reduced in the lesions, as compared with unaffected skin from the same patients or with normal skin from unrelated control subjects. In contrast, the concentrations of hydroxy pro line, an index of collagen, or deoxyribonucleic acid (DNA), a measure of cellularity, were not changed in the lesions. Thus, the results indicate that in the three patients studied, the elastic fibers are defective and reduced in quantity. These observations suggest that the deficiency of elastin in the dermis may lead to development of the cutaneous lesions of anetoderma. 相似文献
33.
Genetic obesity in rats. II. The effect of food restriction on the metabolism of adipose tissue 总被引:1,自引:0,他引:1
The metabolism of adipose tissue from genetically obese rats (Fatty) and lean animals was studied in two experiments. In the first experiment, food intake was regulated at three levels in Fatty rats. One group ate ad lib., a second group was pair fed to lean controls, and the third group received two-thirds of the food eaten by the lean rats. Serum insulin was reduced by restricting food intake. Fat cells were largest in the ad lib.-fed Fatties and smallest in the lean rats. Lipolysis, as measured by glycerol release, was comparable in lean and Fatty rats. Several lipolytic drugs were as effective in fat from the obese as the lean animals. Metabolism of 14C-glucose with or without insulin was reduced in the tissue from Fatty rats and was not corrected by restricting food intake. In the second experiment, lipolysis and lipogenesis were studied by serial biopsies during starvation-induced weight loss. Rats were allowed to eat for 3 days before each biopsy. Reduction of fat cells to the same size as normals did not restore lipogenesis or lipolysis to normal. Reesterification of fatty acids remained high in all experiments with tissues from Fatty rats. 相似文献
34.
Serious infections due to group G streptococci have been infrequently reported. Fifteen such cases are described. Endovascular infection, particularly endocarditis, and septic arthritis were the most common clinical syndromes observed. Despite exquisite in vitro sensitivity of group G streptococci to penicillin G, the in vivo clinical response was disappointing in six of nine patients with either endocarditis or septic arthritis. The group G streptococcal isolates from the patients in this study were uniformly sensitive to the inhibitory and killing action of penicillin G, ampicillin, cefotaxime, cephalothin, cefoxitin, and vancomycin. In contrast, clindamycin, erythromycin, and chloramphenicol had relatively poor bactericidal activity against these strains, including several “tolerant” strains. Timed-kill studies with penicillin G revealed impaired killing of group G streptococci at in vitro conditions of high inocula and stationary growth phases. This may partially explain the poor clinical responses in cases of group G streptococcal endocarditis. 相似文献
35.
Kenneth A. Narahara Ismael Mena Jean C. Maublant Marianne Brizendine J.Michael Criley 《The American journal of cardiology》1984,53(6):812-817
Gold-195m is a new ultra-short-lived radionuclide that can be used for cardiac studies. Accurate, reproducible ejection fraction and ventricular wall motion studies can be obtained from first-transit angiography using commercially available imaging and image-processing equipment. The short half-life of gold-195m (30.5 seconds) makes simultaneous dual isotope imaging possible and substantially reduces the radiation exposure from the isotope angiography.The feasibility and possible benefits of performing dual radionuclide studies were evaluated during a single exercise stress test in 24 subjects with known coronary artery disease (CAD) and in 20 normal volunteers. High-quality first-transit angiograms were obtained in all subjects. An 83% sensitivity and 95% specificity for detecting CAD with thallium-201 imaging was noted in this investigation, suggesting that its diagnostic accuracy was not altered by simultaneous dual isotone imaging. When segmental left ventricular (LV) wall motion was compared with thallium-201 perfusion imaging, divergent results were noted in 15 of 44 subjects. An analysis of the ejection fraction (EF) results at rest and stress provided additional information that could be useful in assessing the clinical significance of such differences in segmental wall motion and perfusion.Simultaneous dual isotope imaging appears to be appropriate for situations in which both LV perfusion and function require evaluation. The use of gold-195m allows such information to be obtained from a single exercise test and can thereby reduce the cost and time required for noninvasive evaluations of patients for CAD. 相似文献
36.
During a six-month period, 929 newborn infants had continuous, direct fetal heart rate monitoring during labor. Of these, 481 were monitored with the Berkeley Bio-Electronics spiral electrode and 448 were monitored with the Corometrics spiral electrode. The over-all incidence of scalp abscess complicating fetal monitoring was 4.5 per cent. In the group monitored with the Berkeley electrode, 25 newborn infants (5.2 per cent) developed a scalp abscess; in the group with the Corometrics electrode, 17 newborn infants (3.8 per cent) developed scalp abscess. The incidence of scalp abscess was not significantly different in the two groups. 相似文献
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38.
Method for intraoperative assessment of organ perfusion and viability using a miniature oxygen sensor 总被引:1,自引:0,他引:1
A specially designed miniaturized Clark polarographic electrode was used to measure organ surface oxygen tension during surgical operations in 10 patients as a means of determining tissue perfusion and viability. When applied to organ surfaces, the sensor noninvasively provides real-time assessment of tissue PO2. Values obtained are dependent on both arterial PO2 and local blood flow and therefore may be used to quantitatively assess local oxygen delivery (perfusion). Measured values may be compared with arterial PO2 or to areas of certain normal perfusion on the same organ to better define the adequacy of local oxygen transport. Tissue temperature is independently measured and may be used to assess the metabolic activity of the tissue monitored. Organ surface oximetry using the miniature PO2 sensor is a practical and repeatable method for the intraoperative assessment of organ perfusion and viability. 相似文献
39.
Pulmonary embolism is described as an infrequent complication of axillary and subclavian vein thrombosis. We have reported our recent clinical experience with 14 patients admitted to the Harbor-UCLA Medical Center who had a clinical diagnosis of axillary and subclavian vein thrombosis documented by phlebography of the thrombosed arm. The causes of thrombosis were effort (three patients), trauma (three patients), drug abuse (four patients), underlying neoplastic disease (three patients), and congenital venous malformation (one patient). Pulmonary emboli were diagnosed by arteriogram, ventilation perfusion scans, and arterial blood gas abnormalities in five patients with respiratory symptoms for an incidence of 35.7 percent. Immediate anticoagulation with heparin, then switching to warfarin sulfate after 5 days, was the standard therapy in all patients. Follow-up examinations between 3 and 24 months demonstrated mild postphlebitic syndrome consisting of pain and minimal swelling in two patients. We conclude that pulmonary emboli may be a more frequent complication of axillary and subclavian vein thrombosis than has generally been recognized. 相似文献
40.