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101.
Evidence for opioid modulation and generation of prostaglandins in sulphur dioxide (SO)2-induced bronchoconstriction. 下载免费PDF全文
BACKGROUND: Inhalation of sulphur dioxide (SO2) provokes bronchoconstriction in asthmatic subjects. Cholinergic mechanisms contribute, but other mechanisms remain undefined. The effect of morphine, an opioid agonist, on the cholinergic component of SO2-induced bronchoconstriction was investigated, and the effect of indomethacin, a cyclooxygenase inhibitor, on SO2-induced bronchoconstriction and tachyphylaxis was studied. METHODS: In the first study 16 asthmatic subjects inhaled either ipratropium bromide or placebo 60 minutes before an SO2 challenge on days 1 and 2. On day 3 an SO2 challenge was performed immediately after intravenous morphine. In the second study 15 asthmatic subjects took either placebo or indomethacin for three days before each study day when two SO2 challenges were performed 30 minutes apart. The response was measured as the cumulative dose causing a 35% fall in specific airways conductance (sGaw; PDsGaw35). RESULTS: Ipratropium bromide significantly inhibited SO2 responsiveness, reducing PDsGaw35 by 0.89 (95% CI 0.46 to 1.31) doubling doses. This effect persisted after correction for bronchodilatation induced by ipratropium bromide. The effect of ipratropium bromide and morphine on SO2 responsiveness also correlated (r2 = 0.71). In the second study SO2 tachyphylaxis developed with PDsGaw35 on repeated testing, being reduced by 0.62 (95% CI 0.17 to 1.07) doubling doses. Indomethacin attenuated baseline SO2 responsiveness, increasing PDsGaw35 by 0.5 (95% CI 0.06 to 0.93) doubling doses. CONCLUSIONS: These results suggest that opioids modulate the cholinergic component of SO2 responsiveness and that cyclooxygenase products contribute to the immediate response to SO2. 相似文献
102.
103.
In a case-control study, 57 manics with antecedent or coexisting nonaffective psychiatric disorders (n = 38) or serious medical illnesses (n = 19) ("complicated mania") were compared with 114 age-, sex-, and year-of-admission-matched controls with no other disorder ("uncomplicated mania"). Significant differences emerged between the three groups in age, marital status, age at onset, number of prior hospitalizations and prior suicide attempts, organic features, and outcome measures (recovery and death rates). Patients were divided into four treatment groups based on primary mode of therapy during index admission; the groups included electroconvulsive therapy, adequate lithium carbonate, inadequate lithium carbonate, and neither treatment. Uncomplicated manics were significantly more likely to receive adequate lithium carbonate and less likely to receive inadequate lithium carbonate than were complicated manics. The latter patients had a significantly poorer immediate response to treatment overall, and to adequate lithium carbonate specifically. Seventy-eight (68.4%) uncomplicated manics had recovered ad discharge, compared with 26 (45.6%) complicated manics. Logistic regression suggested that the influence of comorbidity on outcome was more important for women than men. We conclude that complicated mania is a useful clinical construct. 相似文献
104.
In 1985, two policies designed to reduce hospitalization charges for mastectomy patients were instituted at the M.D. Anderson Cancer Center at Houston. The first was a policy of "same-day" admissions for elective surgery patients, and the second was early postoperative discharge for mastectomy patients with suction catheter drains in place. The economic savings resulting from these policies was analyzed by comparing demographics, operation, stage of disease, hospital stay, hospital charges, and complications for two groups of patients. Fifty-nine consecutive mastectomy patients treated between 1983 and 1984, before these policy changes, had "standard management" consisting of hospital admission 24 hours before surgery and discharge only after the surgical drains were removed. Sixty-one consecutive mastectomy patients treated between 1986 and 1987, after these policy changes went into effect, were admitted from the recovery room after surgery and were discharged with drainage catheters in place, usually within 72 hours. All operations were performed by the same faculty surgeon as a representative experience of the General Surgery faculty. The average hospital stay was reduced from 10.5 to 4.3 days. A mean 39% reduction in hospital charges (from $4867.00 to $2981.00) was achieved by instituting the policies of "same-day" admission and early postoperative discharge with drainage catheters in place. Complication rates were not changed. Implementation of this policy resulted in an estimated savings of $750,000.00 in the hospital care of approximately 400 patients treated at the M.D. Anderson Cancer Center at Houston each year. Adjustments in patient care delivery systems from a predominantly inpatient to an outpatient setting required changes in outpatient nursing responsibilities (although not in new personnel). Patient education and written instructions for home care of surgical wounds and drainage catheters were essential for implementing an early discharge policy. With these facts in mind, hospital admission on the day of operation and early postoperative discharge with drainage catheters in place should be the goal for most mastectomy patients. 相似文献
105.
Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
106.
Andrea N. Bell Robert A. Young Virginia G. Lockard Harihara M. Mehendale 《Archives of toxicology》1988,61(5):392-405
Chlordecone (CD) pretreatment is known to markedly potentiate CCl4 hepatotoxicity. Previous studies have shown that prior exposure to CD obtunds the increased hepatocellular regeneration and repair observed in non-treated rats challenged with a single, low dose of CCl4. These observations allowed us to hypothesize that suppression of hepatic regeneration and tissue repair by CD + CCl4 combination treatment might be involved in this interaction. To test this hypothesis, CCl4 hepatotoxicity was evaluated in actively regenerating livers using CD-treated (10 ppm in the diet for 15 days), surgically partially hepatectomized (PH) male Sprague-Dawley rats. Rats undergoing no surgical manipulation (CTRL) and sham operation (SH) were included as appropriate controls. Surgical manipulations were conducted on day 15 of the dietary protocol. Based on liver-to-body weight ratios (LW/BW), mitotic indices, hepatic cytochrome P-450 content, and hepatic glutathione (GSH and GSSG) levels, PH-induced hepatocellular regeneration was not affected by pretreatment with CD. Thus, the PH model was considered valid for assessing the effects of CD + CCl4 combination treatment. CCl4 (100 l/kg; i.p.) was administered 1, 2, 4 or 7 days after the surgical manipulations. Hepatotoxicity was assessed 24 h later by measuring LW/BW and serum enzymes (SGPT, SGOT and ICD) in all four groups. Hepatic histopathological, histomorphometric and lethal effects were assessed in animals receiving CCl4 1 or 7 days after the surgical manipulations. CCl4-induced increases in LW/BW were observed in CD + PH rats receiving CCl4 4 or 7 days post-PH, but not in the 1 or 2 day post-PH groups in which the hepatocellular regeneration was maximal. CCl4-induced serum enzyme elevations were significantly less in the CD + PH rats as compared to CD + SH. This decrease in the serum enzyme elevations was most prominent in the 1 day post-PH group, where the hepatocellular mitotic activity was most pronounced. CCl4 lethality, assessed in the 1 day post-surgical manipulation group, was also decreased in the CD + PH rats in comparison to CD + SH rats. Such a protection was not observed in rats receiving CCl4 7 days post-PH. These data are consistent with and are supportive of the hypothesis that a suppression of otherwise normally stimulated hepatocellular regeneration following low-dose CCl4 administration is involved in the marked amplification of CCl4 toxicity by CD.Abbreviations CD
chlordecone
- GSH
reduced glutathione
- GSSG
oxidized glutathione
- PH
partial hepatectomy
- SH
shamhepatectomy
- CTRL
control, not surgically manipulated
- N
normal diet
- LW/BW
liver weight-to-body weight ratio
- SGPT
serum glutamic; pyruvic transaminase
- SGOT
serum glutamic oxaloacetic transaminase
- ICD
isocitrate dehydrogenase
These studies were made possible by a grant from the US Environmental Protection Agency R-811072A preliminary report of these findings was presented at the 70th Annual Meetings of the Federation of American Societies for Experimental Biology at St. Louis, MO (Fed Proc 45: 1051, 1986)A. N. Bell is a Predoctoral Toxicology Trainee and Robert A. Young is a Postdoctoral Trainee supported by Toxicology Training grant from National Institute of Environmental Health Science ES-07045 相似文献
107.
Richard O. Shillaker Graham M. Bell John T. Hodgson Michael D. J. Padgham 《Archives of toxicology》1989,63(4):283-288
Current European Community (Annex V) guidelines recommend the use of 20 test animals in the guinea pig maximisation test for skin sensitisation. The suitability, for classification and labelling purposes, of reducing the number of test animals has been examined by analysing the results of 40 studies submitted to the Health and Safety Executive, and by the use of a mathematical model. Our results suggest that in most cases an experiment with ten test animals can be used to determine satisfactorily whether a substance should be labelled with the risk phrase may cause sensitisation by skin contact. However, serious consideration should be given to the need for additional investigation if two or three of the ten test animals show a sensitisation response. The highest nonirritant concentration of a substance should be used at challenge. Clearer guidance in Annex V on evaluating challenge responses would be beneficial. 相似文献
108.
The in vitro anti-SRBC response of several murine strains declined markedly with age in parallel with an increase in the activity of suppressor cells in the spleen and bone marrow which prevented early events during the induction of the immune response. These suppressor cells released soluble mediators and lacked the characteristics of mature T cells or macrophages. In addition the suppressor cell in the bone marrow could be removed on anti-Ig columns and fractions of old splenic suppressor cells sedimenting at 0.32 cm/h were greatly enriched in surface Ig bearing cells. Old immunodepressed mice did not lack potentially immunocompetent cells since the antibody response of old spleen cells could be restored by specifically activated T cells or lipopolysaccharide which act on B cells. These results suggest that a rise in the activity of non-T suppressor cells in the spleen and bone marrow may account, in part, for the depression in humoral immunity observed in aging mice. 相似文献
109.
Herpes simplex virus type 1 (HSV-1) expresses a complex of two virally encoded glycoproteins, gE and gl, which is capable of binding nonimmune human IgG. The gE-gl complex has thus become known as an Fc receptor (FcR), which reportedly binds human IgG subclasses in the order IgG4 > IgG1 > or = IgG2 and does not bind IgG3 from many individuals. There is, however, allelic variation in the genes encoding the human IgG1 heavy chain constant region and this gives rise to allotypes of IgG1. Using recombinant monoclonal IgG molecules of known isotype and mutants thereof we have unexpectedly discovered that the HSV-1 FcR discriminates between IgG1 allotypes. This is evidence of functional differences between IgG1 allotypes that may account for their distribution in populations. Furthermore, these findings suggest HSV-1 FcR binding sites on the IgG molecule some distance from the proposed binding site in the CH2-CH3 domain interface. 相似文献
110.
Physiologic differences in hemoglobin variants 总被引:2,自引:0,他引:2
Thompson Robert B.; Warrington Richard L.; Bell Warren N. 《The American journal of physiology》1965,208(1):198-202