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Free hydrocortisone, hydrocortisone incorporated into microspheres and empty microspheres have been administered orally to rats with carrageenan-induced hindpaw inflammation. Hydrocortisone administered in particles was effective at a lower dose than free steroid in reducing inflammation. Inflammatory exudates were able to release steroid from the microspheres by proteolytic degradation.  相似文献   
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Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.  相似文献   
5.
Factors relating to the transfer of latex microspheres of 0·87 μm mean diameter from the gastrointestinal tract (GIT) to the circulation have been investigated. The rapidity of appearance and the number of particles increased when the volume of water used as a suspending vehicle was increased. This was probably due to barrier cell integrity being compromised so that the movement of particles across the enterocytes would be enhanced. Particles were swept into these channels by the waterflow. The tonicity of the fluid was important as isotonic and hypertonic saline were not as affective as water in transferring particles. Particles were transferred from GIT segments adjacent to the stomach which may in part explain the rapid appearance of particles in the circulation. Particle uptake was blocked by cytochalasin B which suggests an active component may also be involved.  相似文献   
6.
Regulatory peptides in the heart and major vessels of man and mammals   总被引:10,自引:0,他引:10  
Studies on the distribution of peptides in human tissues have been made either by measuring responses to localized stimuli or by subjecting extracts of different regions to radioimmunoassay (RIA). Attempts at isolating regulatory peptides from the mammalian tissues have resulted in the isolation of many bioactive fragments. Later, modification of initial isolation methods led to the identification of the native molecules in various tissues and body fluids. The present study examined atrial natriuretic peptide (ANP) and several other peptides in cardiac tissues of several species of laboratory mammal and human beings; using a sensitive and highly specific radioimmunoassays.In all the species studied, ANP-like immunoreactivity appeared to be highest in the heart tissue of rat. The peptide was highest in the right atrium (RA) of rat and lowest in the RA of guinea pig (P< 0.002). Neuropeptide Y (NPY) another abundant cardiac peptide was present in the cardiac tissues of all species but was more in the left atrium (LA) than the RA of all species (P<0.05). Calcitonin gene-related peptide (CGRP) was present throughout the cardiovascular system of the rat and guinea pig. Small but detectable amount of Neurotensin (NT) immunoreactivity was found in the rat but was consistently negative in the guinea pig cardiac tissues (P< 0.05). Substance P (SP) immunoreactivity was detected in the rat and higher quantities being in the Aorta but no trace of the peptide was detected in the left ventricle, aorta nor the pulmonary vein of post mortem human.Though the structure of most of the species studied has been elucidated, the primary structure of guinea pig ANP has not been fully generated. Thus the data obtained may suggest that in keeping with these mammalian peptides, the primary structures may be variant. With most of the peptides studied (e.g. ANP, Neuropepdide Y), immunoreactivity occurs predominantly in the atrial tissues, but is also present in vessels outside the heart, a finding which may be of functional significance.  相似文献   
7.
To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated, using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation. Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin.  相似文献   
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In this study, we aimed to compare the effects of forced-air warming upper body blankets and forced-air warming underbody blankets on intraoperative hypothermia in patients who were planned to undergo open abdominal surgical operations in which extensive heat loss occurs. This prospective and randomized study included 92 patients who would undergo lower abdominal surgery under general anesthesia. Patients were randomized by closed envelope method and divided into two groups. Group I (n:46) included the patients who would receive warming with forced-air warming upper body blanket, and Group II (n:46) consisted of the patients who received warming with forced-air warming underbody blanket. Central body temperature was recorded by measuring with a temperature probe placed in distal esophagus. Demographic data, amount of fentanyl, crystalloid and blood products used, duration of operation, type of operation, hemodynamic parameters, shivering and thermal damage information were recorded. There was not any statistically significant difference among the patients in terms of demographic data, amount of fentanyl, crystalloid and blood products used, duration and type of operation and hemodynamic parameters. No difference was found between the groups in terms of body temperatures (Group I:36.1?°C, Group II:36.3?°C, respectively) (P?>?0.05). Forced air warming underbody blanket can be as effective as forced-air warming upper body blankets in preventing intraoperative hypothermia. They can be alternative in cases where use of forced-air warming upper body blankets is not feasible.  相似文献   
10.

Objectives

The present study aims to specify the role of l-carnitine in the pathogenesis of endometrial cancer by comparing the serum total l-carnitine levels of endometrial cancer patients with those of healthy women.

Methods

Serum total l-carnitine concentrations were measured in patients with endometrioid-type endometrial cancer (n = 20) and healthy controls (n = 20) who were matched with respect to age and body mass index (BMI).

Results

Stage I endometrial cancer was diagnosed in 12 women (60.0 %) whereas three women (15.0 %) had stage II disease, three women (15.0 %) had stage III disease and two women (10.0 %) had stage IV disease. The healthy controls and endometrial cancer patients were statistically similar in aspect of age, gravidity, parity, BMI, waist-to-thigh ratio, waist-to-hip ratio, menopause, complete blood count parameters, and serum biochemistry. Serum total l-carnitine levels of women with endometrial cancer were significantly lower than those of healthy women (respectively, 5,519.4 ± 2,712.5 vs 7,940.8 ± 3,566.6 ng/dl, p = 0.021). Moreover, serum total l-carnitine levels decreased significantly and progressively with advancing stage (stage I vs II vs III vs IV; 6,294.0 ± 2,885.1 vs 5,800.0 ± 441.2 vs 4,016.0 ± 2,833.3 vs 2,560.0 ± 67.9 ng/dl; p = 0.021).

Conclusions

This is the first study to hypothesize that l-carnitine deficiency participates in the pathogenesis of endometrial cancer by means of a mechanism which is unrelated with obesity and increased amount of fat in human body.
  相似文献   
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