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991.
Symptoms of tobacco withdrawal. A replication and extension 总被引:19,自引:0,他引:19
Smokers (n = 315) who wished to quit were randomly assigned in a double-blind manner to groups using either nicotine or placebo gum. Self-reported and observed symptoms of tobacco withdrawal were collected before cessation and at follow-ups of 1 to 2 weeks, 1 month, and 6 months. Self-reported and/or observed anger, anxiety, craving, difficulty concentrating, hunger, impatience, and restlessness were the most prominent symptoms of tobacco withdrawal. These symptoms had returned to precessation levels by 1 month except increased weight, hunger, and craving continued for 6 months in many smokers. Nicotine gum decreased most symptoms, including craving and hunger but not weight. Abstinent smokers with more intense withdrawal were not more likely to relapse. Abstinent smokers who gained more weight were less likely to relapse. 相似文献
992.
D A Hale K A Waldorf J Kleinschmidt R H Pearl A E Seyfer 《Journal of pediatric surgery》1991,26(8):914-920
Small intestinal transplantation represents a potentially therapeutic procedure for individuals with short gut syndrome. The purpose of this study was to develop a model for small intestinal transplantation in primates that is: technically feasible without microsurgery; consistent in the prevention of allograft rejection; functional in terms of nutrient absorption; and compatible with harvest for multiple organ procurement. First, autotransplantations on four rhesus monkeys were performed in order to study a variety of harvesting techniques and vascular anastomoses. Then, a study was performed with 14 heterotopic allotransplants in 4 baboons and 10 rhesus primates. The successful donor model consisted of division of the pancreas, harvesting the small bowel with a superior mesenteric artery and portal vein pedicle. The allograft vascular pedicle was anastomosed to the recipient's common iliac vessels in end-to-side fashion. The graft was transplanted as an out-of-continuity loop, both ends being exteriorized as stomas providing access for absorption studies and biopsy. Three immunosuppressive regimens were tested: (1) cyclosporine A (CyA) 20 mg/kg/d, solumedrol (SML) 2 mg/kg/d, and graft irradiation (150 rad) (n = 4); (2) CyA 20 mg/kg/d and SML 2 mg/kg/d (n = 3); and (3) CyA 40 mg/kg/d, SML 2 mg/kg/d, and azathioprine 5 mg/kg/d (n = 3). There were 4 deaths due to technical error in the first 24 hours. Weekly graft biopsy, serum CyA levels, complete blood count, and automated 24-channel serum analysis were performed. Grafts surviving greater than 14 days underwent absorption study via luminal perfusion with sucrose, maltose, dextrose, Pregestimil, xylose, and cyclosporine.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +/- 16 micrograms/dl (mean +/- SE) to 24 +/- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +/- 6 micrograms/dl to 12 +/- 1 micrograms/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disappearance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +/- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +/- 0.6%) at 9 h after intravenous injection of 59Fe chondroitin ferrous sulfate, there was no difference between the amount of 59Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the 59Fe once it has been released from the mononuclear phagocyte system into the plasma. 相似文献
994.
995.
996.
Total hip arthroplasty. The role of antiinflammatory medications in the prevention of heterotopic ossification 总被引:6,自引:0,他引:6
Postoperative prophylaxis with antiinflammatory medications, primarily indomethacin, is extremely effective in preventing the severest degrees of heterotopic ossification (HO) after a total hip arthroplasty (THA) and the recurrence of excised HO developed after a previous hip surgery. Prophylaxis with indomethacin should be given in 25-mg doses three times daily for at least three weeks, starting on the first postoperative morning. However, a shorter treatment period may be equally effective in preventing the severest degrees of HO, and a postoperative delay of five days before the initiation of prophylaxis does not seem to be followed by the development of severe HO. As evaluated one year after surgery, treatment with antiinflammatory medications in the immediate postoperative weeks did not increase the incidence of implant-bone interface radiolucencies, aseptic loosening, or revisions in cemented or cementless THAs when compared with cases that did not have postoperative treatment. However, although no major complications have been reported regarding the use of antiinflammatory medications in the prevention of HO after THA, orthopedic surgeons prescribing such treatment should be aware of their contraindications as well as early and late side effects. Since several antiinflammatory agents are reported to be effective in preventing HO, future reports dealing with HO after THA should always include information about the postoperative antiinflammatory treatment used. 相似文献
997.
M Ia Ratner M A Brodski? M L Zubkin I I Stenina I M Slutskin 《Terapevticheski? arkhiv》1991,63(6):12-15
Tubulointerstitial alterations associated with chronic glomerulonephritis (CGN) are definitely dependent on the clinical type of CGN and are accompanied by a decrease of homeostatic functions (the rate of glomerular filtration, osmotic concentration and dilution of urine, hydruresis, the magnitude of CH2O, excretion of ammonium and hydrogen ions, the ratio of ammonium excretion to hydrogen ion excretion). Maximal osmotic concentration and ammonium excretion show an especially considerable decrease. The clinical type permitting one to diagnose rather than to reject the presence of alterations and the status of certain tubular functions, osmotic concentration in particular and, to a less degree, ammonium excretion, permitting to reject the presence of the tubulointerstitial component (TIC) are of known but restricted importance for TIC recognition. The TIC can be diagnosed more adequately in exploring definite pairs of renal functions, particularly osmotic concentration of urine and ammonium excretion and maximal hydruresis and excretion of hydrogen ions. This approach is both helpful in confirming and rejecting the presence of the TIC. Of special value is the combined assessment of the clinical type and maximal osmotic urine concentration data. 相似文献
998.
W. Scharenberg 《Archives of environmental contamination and toxicology》1991,21(4):536-540
Brain, livers, and subcutaneous fat of 50 Cormorants (Phalacrocorax carbo sinensis, Blumenbach 1798) were analyzed for 6 PCB congeners. The birds had been shot in autumn 1985 and 1986 in Schleswig-Holstein, FRG. Subcutaneous fat was the highest contaminated tissue, while brain had accumulated the lowest concentrations. An accumulation by age was statistically significant between the groups of 1st year/2nd year birds and after 2nd year birds. There were no differences evident between sex and between weight groups. Pooled samples were analyzed by GC-MS; 61 congeners could be identified in adipose tissue, 54 in liver, and 49 in brain. 18 congeners were quantified in spotchecks, and some samples were analyzed by multidimensional gaschromatography. In comparison to fish they consume, the fat of cormorants was concentrated with PCBs 10–100 times more than marine fish, and 100–1,000 times more than freshwater fish. This species is a suitable bioindicator for PCBs. 相似文献
999.
Zia Hossein Ma Joseph K. H. O'Donnell John P. Luzzi Louis A. 《Pharmaceutical research》1991,8(4):502-504
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant. 相似文献
1000.
alpha 2-Adrenergic receptors (ARs) are involved in central nervous system (CNS) control of blood pressure. It is now known that there are three human genes that encode subtypes of alpha 2-ARs, but little is known regarding the distribution of these subtypes throughout the CNS. The availability of receptor clones allows the mapping of mRNAs encoding the individual alpha 2-AR subtypes in the CNS. In this communication, we report that there are three, closely related rat alpha 2-AR genes. We have developed subtype-specific hybridization probes from each of these genes and have used these reagents to measure alpha 2-AR subtype mRNA accumulation in extracts of discrete regions of the rat CNS. We found that mRNAs encoding the alpha 2A-AR and alpha 2C-AR subtypes are distributed widely, but unevenly, throughout the rat CNS. The A subtype is prominent in the midbrain, brainstem, spinal cord, pituitary and diencephalon while the C subtype predominates in basal ganglia and cerebellum. The cortex, olfactory bulb and hippocampus contain roughly equal amounts of the alpha 2A- and alpha 2C-AR mRNAs. A third subtype's (alpha 2B-AR) mRNA is far less abundant in brain tissues, and is only found in the diencephalon. 相似文献