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81.
82.
In developing countries, maternal infections during lactation are common. In this study, we evaluated the effect of acute maternal postpartum infection on the composition of colostrum and early milk with special emphasis on milk proteins and trace elements. The study was carried out in two maternity hospitals in Lima, Peru. Subjects were normally nourished women (body mass index (BMI) > 20.0) who intended to exclusively breastfeed their child and who had fever and clinical symptoms of infection within the first 48 h postpartum ( n = 34). Non-ill women of similar characteristics were selected as controls ( n = 23). Blood and milk samples were taken on days 1 and 14 postpartum. An acute phase response was confirmed by significantly increased serum levels of C-reactive protein in infected women. Serum zinc levels increased significantly from day 1 to day 14, but were not affected by infection. Serum copper levels were significantly higher in ill women than in non-ill women on day 1. All participating women were breastfeeding on day 14. Whey protein levels, the whey/casein ratio and total protein levels decreased significantly with time, but were not affected by infection. There were no differences in milk iron or copper levels with time or infection. Milk zinc levels decreased significantly with time, but were not affected by infection. Maternal infection during the early postpartum period does not appear to adversely affect the initiation of lactation or milk protein and trace element contents.  相似文献   
83.
J A O''Neill  Jr  M D Caldwell    H C Meng 《Annals of surgery》1977,185(5):535-542
Parenteral nutrition may protect patients unable to eat from malnutrition almost indefinitely. If fat is not also given EFAD will occur. This outlines a prospective study of 28 surgical patients on total intravenous fat-free nutrition to determine the developmental course of EFAD and the response to therapy. Twenty-eight patients ranging from newborn to 66 years receiving parenteral nutrition without fat had regular determinations of the composition of total plasma fatty acids and the triene/tetraene ratio using gas liquid chromatography. Physical signs of EFAD were looked for also. Patients found to have evidence of EFAD were treated with 10% Intralipid. Topical safflower oil was used in three infants. Total plasma fatty acid composition was restudied following therapy. In general, infants on fat-free intravenous nutrition developed biochemical EFAD within two weeks, but dermatitis took longer to become evident. Older individuals took over four weeks to develop a diagnostic triene/tetraene ratio (greater than 0.4; range 0.4 to 3.75). Therapeutic correction of biochemical EFAD took 7 to 10 days but dermatitis took longer to correct. Cutaneous application of safflower oil alleviated the cutaneous manifestations but did not correct the triene/tetraene ratio of total plasma fatty acids. These studies indicate that surgical patients who are unable to eat for two to four weeks, depending upon age and expected fat stores, should receive fat as a part of their intravenous regimen.  相似文献   
84.
A comparison was made between untreated McCoy cells and McCoy cells treated with Cytochalasin B for the isolation of chlamydiae of subgroup A. Chlamydiae were isolated in both cell systems from 125 specimens, whereas six agents were isolated only in untreated cultures and seven agents were isolated only in Cytochalasin B treated cultures.  相似文献   
85.
Som  PM; Lanzieri  CF; Sacher  M; Lawson  W; Biller  HF 《Radiology》1985,154(2):407-412
Twenty-eight patients had combined conventional drip infusion CT scans. The information about the anatomic location of the lesion, its configuration, its cross-sectional appearance, its vascularity (as determined by dynamic signature curves), and its clinical presentation were considered as a single overall unit. This diagnostic approach allowed a diagnosis to be made on virtually all of these enhancing lesions without resorting to either a digital venous imaging study or angiographic procedure. In 17 of these cases, such an invasive second procedure was performed either to confirm the CT impression as part of this study or as part of a therapeutic embolization procedure.  相似文献   
86.
87.
Seventy-five patients with hemoptysis were treated with bronchial artery embolization (BAE). The procedure was performed with Hexabrix (sodium methylglucamine ioxaglate), Mikaelson catheters, and Gelfoam particles. Angiographic evaluation of the bronchial artery anatomy revealed ten different configurations, which are described. The embolization attempt failed in three cases (4%); eight additional patients (10.7%) were excluded from the series because of inadequate data. In the remaining 64 patients, 41 underwent BAE alone and 23 underwent either chemotherapy or surgery in addition to embolization. Immediate control of hemoptysis was achieved in 49 of 64 patients (76.6%). Long-term control of hemoptysis was achieved in 46 of the 56 patients included in the long-term follow-up (82.1%). Eight of the 64 patients were lost to follow-up, which ranged from one to 47 months (mean 24.8 months). Hemoptysis recurred in 12 of 56 patients (severe in 10, mild in 2) (21.4%). Twelve patients died (21.4%), five of them due to hemoptysis (8.9%). None of the patients who died of hemoptysis had responded to initial BAE. It is concluded that BAE is an effective treatment for immediate control of life-threatening hemoptysis, allowing long-term control of bleeding in the majority of patients.  相似文献   
88.
Previous work has left unresolved questions on whether promethazine reduces the sensation of breathlessness. This study was designed to provide a definitive answer and to determine the contributions from promethazine's major pharmacological actions. Twelve healthy subjects participated in a double-blind, within-subject comparison of promethazine and placebo each given acutely by mouth. Breathlessness was assessed with visual analogue scales during a progressive exercise test and was related to minute ventilation. Promethazine had no significant effect on breathlessness nor on the relationship between breathlessness and ventilation. The role of histamine-antagonism was investigated in a subgroup of the subjects by administration of mebhydrolin. No effect on breathlessness was detected. In contrast, the standard phenothiazine, chlorpromazine, caused a marked and statistically significant reduction in breathlessness without affecting ventilation and without causing detectable sedation. This unexpected finding merits further study in patients and is discussed with reference to the role of chlorpromazine as a constituent of Brompton's Mixture.  相似文献   
89.

Background and purpose:

Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery.

Experimental approach:

The cytosolic Ca2+ concentrations ([Ca2+]i), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery.

Key results:

Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR1) antagonist, while it was mimicked by PAR1-activating peptide (PAR1AP), but not PAR4AP. The thrombin-induced contraction was associated with a small elevation of [Ca2+]i and an increase in MLC20 phosphorylation. Thrombin and PAR1AP induced a greater increase in tension for a given [Ca2+]i elevation than that obtained with high K+-depolarization. They also induced a contraction at a fixed Ca2+ concentration in α-toxin-permeabilized preparations.

Conclusions and implications:

The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR1 and thereby increasing the sensitivity of the myofilament to Ca2+. This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH.  相似文献   
90.
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