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71.
Endogenous nociceptin signaling and stress-induced analgesia   总被引:2,自引:0,他引:2  
Nociceptin/orphanin FQ (NC) and its receptor (OP4) have been implicated in pain transmission. The aim of the present study was to investigate the role of the NC/OP4 system in stress-induced analgesia (SIA). The tail-withdrawal assay was performed in mice stressed by forced swimming in water at 15 degrees C (high severity swims) or 32 degrees C (low severity swims). High severity swims produced a naloxone-insensitive antinociceptive effect which was blocked by supraspinal NC (1 nmol). The selective OP4 receptor antagonist, [Nphe1]NC(-13)NH2 (30 nmol), was inactive by itself, but prevented the effect of NC. Low severity swims produced a milder analgesic effect that was partially antagonized by naloxone, completely blocked by NC and potentiated by [Nphe1]NC(-13)NH2. These findings confirm the anti-analgesic role of supraspinal NC and suggest that endogenous NC signaling counteracts the opioid component of SIA.  相似文献   
72.
Thirty patients undergoing allogeneic bone marrow transplantation (BMT) for hematologic malignancies received ciclosporin A (CS-A) as prophylaxis of graft-versus-host disease (GVHD). CS-A trough levels were determined in whole blood by radioimmunoassay (RIA); results were not used to adjust the CS-A dosage. Neither the dose of CS-A administered nor the CS-A concentration and fluctuation of blood levels during the first 15 days after BMT correlated with acute GVHD. Conversely in the 13 patients with acute GVHD, CS-A concentrations in the 10 days prior to the onset of the disease were increasingly lower with increasing severity of GVHD. Moreover, patients without GVHD had higher CS-A concentrations in a matched period of time. Upon withdrawal of CS-A treatment, 7 patients developed GVHD. There was no possibility to predict who would do so, but the analysis of CS-A disappearance profiles indicates that effective CS-A concentrations might be lower during long-term treatment than the concentrations required early after transplant. Despite these relationships, CS-A concentration is of little predictive value in the individual patient because of the considerable overlap among patients.  相似文献   
73.
Pharmacological properties of a novel class of 5-HT3 receptor antagonists.   总被引:2,自引:0,他引:2  
The pharmacological profile of six representative members of a novel class of 5-HT3 receptor antagonists is described. The compounds are esters and amides of benzimidazolone-1-carboxylic acid with a basic azabicycloalkyl moiety (compounds 1-3) and their respective ethyl derivatives (compounds 4-6). In isolated preparations (rabbit heart and guinea pig ileum) all compounds antagonized the 5-HT3 receptor-mediated effects of serotonin, with potencies comparable with those of the reference compounds, ICS 205.930 and GR 38032F (-log IC50 9.30-11.9 and 6.8-8.20, in heart and ileum, respectively). In the anaesthetised rat, all agents potently inhibited the Bezold-Jarisch reflex whether given i.v. or i.d. I.v. administration of compounds prevented cisplatin-induced emesis in dogs (ID50 ranging from 3.7 to 147 micrograms/kg). All agents accelerated gastric emptying of solids in rats (ED50 about 10-160 micrograms/kg i.p.). In addition, compounds 4 and 5 were able to stimulate 5-HT4 receptors in the isolated guinea pig ileum, as well as enhance contractile activity in the Heidenhain gastric pouch of dogs, showing clearcut prokinetic properties.  相似文献   
74.
In the present paper the physical properties and the utilization of the surgical forceps has been explained. The correct working positions during dental extraction in different oral quadrants have been examined.  相似文献   
75.
We compared the feasibility and efficacy of autologous bone marrow (ABMT) and peripheral blood progenitor cell transplantation (PBSCT) performed after an identical induction/consolidation in adults with acute myeloid leukemia (AML). From January 1993 to June 1996 91 consecutive AML patients were enrolled in a program consisting of anthracycline-based induction and high-dose cytarabine consolidation (NOVIA). Until May 1994 ABMT was performed; from June 1994, if PBSC collection was adequate, PBSCT was performed. Out of 88 evaluable patients, 73 obtained a complete remission (CR) and 15 were resistant. Allogeneic bone marrow transplantation was performed in 16 patients. Forty-four (50%) were given autologous stem cell transplantation. ABMT was performed in 21 cases; twenty-nine patients were given G-CSF mobilization after NOVIA administration. An adequate number of PBSC was obtained in 23/29 (79%) cases, which were then re-infused. Median times to both neutrophil and platelet recovery from transplant were significantly shorter for the PBSC group (17 vs 36 days to 500 PMN/microl, P < 0.01; 20 vs 150 days to 20000 platelets/microl, P < 0.02; 37 vs 279 days to 50000 platelets/microl, P < 0.03), as were days of hospitalization after the reinfusion (18 vs 33, P < 0.03) and median days to transfusion independence. Toxicity was not significant in either group. After a minimum follow-up for live patients of 24 months (longer than the mean time for relapse observed for the PBSC series - 14 months) the percentage of relapses was similar: 11 of 21 (52.4%) and 12 of 23 (52.1%) in the ABMT and PBSC groups, respectively. Our results indicate that autologous PBSC transplantation, performed after an intensive chemotherapy regimen, is not inferior to ABMT in terms of disease-free survival and allows faster recovery times and reduced need for transfusion support.  相似文献   
76.
77.
Healthcare-associated infections are a critical challenge for the public health sector. Most are acquired through contact, predominantly with the hands of health care personnel. Hand hygiene, therefore, is the single most effective measure for preventing and controlling infectious diseases. Recently, cases of acute hepatitis C occurred in patients who had undergone contrast-enhanced computed tomography. This was probably related to inadequate handling by health care staff. Rigorous compliance with standard precautions is therefore compulsory even in radiology, a setting traditionally considered at low risk for the transmission of pathogens. Adherence to standard precautions is still poor and the persistence of inappropriate practices responsible for preventable incidents is very common in radiology, often owing to underestimation of risk. Radiology units must promote compliance with correct hand hygiene through appropriate education programmes and provision of adequate areas and hand hygiene products. The evidence base to support the use of alcohol-based hand rub is demonstrating that these formulations are effective in improving hand hygiene compliance and preventing infections.  相似文献   
78.
Sorbinil (1), a spirocyclic hydantoin, is a potent inhibitor of the enzyme aldose reductase. Simulation of the rigid spirocyclic ring orientation found in sorbinil was achieved with nonspirocyclic 5-[5'-chloro-2'-(alkylsulfonyl)-phenyl]hydantoins and 5-[5'-chloro-2'-[(N-alkylamino)sulfonyl]phenyl]hydantoins. The 2'-substituent (SO2R) was sufficiently large to hinder rotation of the hydantoin ring, forcing an orientation similar to that of a spirocyclic hydantoin. Calculated conformational preference, X-ray data, and inhibitory IC50 values for these nonspirocyclic 2'-substituted (SO2R) phenylhydantoins are in accord with what is expected for spirocyclic hydantoins and comparable to those of sorbinil.  相似文献   
79.
A living cellular allogeneic dressing made up of cultured keratinocytes adhering to a collagen film was used to treat 20 leg ulcers of various aetiologies in 16 patients. A reduction in pain was noted in 80% of cases, and promotion of granulation tissue in the ulcer bed in 70% of cases. In 10 patients, epithelialization of 71 +/- 29% of the ulcer was noted at Day 30.  相似文献   
80.
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