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991.
Alcohol and other drug (AOD) use behaviors of health professions students (HPS) were assessed by surveying both university-based HPS and other nursing programs in a Midwestern state in 1999. Response was 2,646 (56.4%) of surveyed students. Family history of alcohol-related and drug-related problems were reported by 39.8% and 13.9%, respectively, with 42.6% of respondents reporting one or both. Among nursing respondents, 48.1%, 19.2% and 51.1%, respectively, reported family problems with alcohol, drugs, or one or both. Past-year alcohol use was comparable to undergraduate college students (UCS) nationally (83%); heavy drinking, tobacco and recreational drug use by HPS were lower. Past year drug use was highest among medical students. Marijuana was the predominant illicit drug; medical students and males most often reported use. Health professions educational systems should proactively address student AOD prevention, education and assistance needs.  相似文献   
992.
The effect of ciclosporin (CS) and methotrexate (MTX) on the development of graft-versus-host (GvH) disease was examined after small bowel allotransplantation in the rat. The drugs were tested either alone or in combination. Lewis small bowel allografts were transplantated into Brown Norway recipients in a heterotopic position. The native small bowel, spleen, liver, skin, mesenteric lymph nodes and the kidney of the recipients were examined histologically 5, 10 and 20 days after allotransplantation. Intraepithelial lymphocyte numbers were determined quantitatively in the native small bowel. The relative spleen weight of the host was determined after sacrifice for estimation of the severity of GvH disease. Grade I GvH reaction of the native small bowel occurred in the animals without immunosuppression, but graft rejection predominated in this group. Treatment with CS was effective in the early postoperative periods; after 10 and 20 days GvH lesions in the native small bowel were comparable to those observed in the allogeneic combinations. MTX had a detrimental effect on the allografts and the GvH reaction was augmented. When CS and MTX were combined, GvH lesions were comparable to those in the animals treated solely with CS. Animals, however, suffered from heavy side effects. The spleen, liver, lymph nodes and kidney exhibited only unspecific histologic changes, which could not unequivocally be recognized as a GvH reaction. This was true for all groups. As a conclusion it can be said that GvH reaction occurs in the early postoperative period in a fully allogeneic model and cannot be prevented by CS in the dosae used. MTX was not seen to be of any value in this regard.  相似文献   
993.
Activated macrophages are known to oxidatively metabolize L-arginine to nitric oxide and citrulline. We have recently shown that nitric oxide is a potent inhibitory molecule in the in vitro rat mixed-splenocyte culture, resulting in inhibition of proliferation and cytolytic T-cell induction. We undertook this study using the sponge matrix allograft model in the rat to determine whether nitric oxide plays a role in an in vivo allograft response. Our experiments showed that on day 6 after grafting, when cytolytic activity of allograft-infiltrating cells is first detected, allogeneic graft fluid contains higher levels of NO2-/NO3- (the stable endproducts of nitric oxide metabolism) than syngeneic graft fluid. Furthermore, evaluation of the supernatants of cultured graft-infiltrating cells revealed that allogeneic graft-infiltrating cells spontaneously produce higher amounts of nitric oxide than syngeneic graft-infiltrating cells. The nitric oxide production was inhibited in the presence of NG-monomethyl-L-arginine (NMA), the competitive inhibitor of nitric oxide production. Most of the nitric oxide production was observed in the adherent macrophage fraction of the allograft-infiltrating cells. When allograft-infiltrating cells were cultured in the presence of NMA, donor-specific cytolytic activity was observed, whereas allograft-infiltrating cells cultured in the absence of NMA showed no cytolytic activity. These data show that nitric oxide production may play an important regulatory role in the allograft response.  相似文献   
994.
New long-acting beta 2-adrenoceptor agonists, formoterol and salmeterol, may soon appear in several European countries for treatment of asthma. This review examines currently available information and compares the basic pharmacology and describes the clinical effects of these new drugs. The long duration of bronchodilation seen in clinical studies seems to be similar, whereas in isolated tissues there might be a difference in the binding characteristics to the beta 2-adrenoceptor. Long-acting beta 2-agonists could have an inhibitory effect on inflammatory events related to asthma, but the clinical relevance of these effects is not clear at present. Long-term studies up to one year with both new drugs have not shown any unexpected side-effects, and no tachyphylaxis to beta-adrenoceptor stimulation has been reported. Patients appear to strongly prefer the new drugs compared to the short-acting beta 2-agonists. The potential place for these drugs in the treatment of asthma is discussed and some pitfalls pointed out. It is likely that the long-acting beta 2-agonists will be beneficial to many asthmatic patients.  相似文献   
995.
This study compared the results of reflex modification (RM)--an objective technique for assessing brainstem sensorineural processing--with those of auditory brainstem response (ABR) for a group of high-risk infants at comparable postconceptional ages. For the RM procedure, an eyeblink-eliciting tap to the glabella was presented either alone or accompanied by a brief 90dB SPL tone. 37 high-risk infants were tested with both RM and ABR at a mean postconceptional age of 37.3 weeks. Seven had an increased brainstem conduction time ('failed ABR') and eight did not exhibit significant reflex augmentation ('failed RM'), seven of whom also failed the ABR. These data provide evidence that sensory stimuli which affect the neural mechanisms responsible for the organization of the startle response and auditory processing share essential neural components.  相似文献   
996.
We report the two-dimensional and Doppler color flow mapping echocardiographic findings in a neonate with left circumflex coronary arteriovenous fistula to a left superior vena cava. Doppler color flow mapping, in concert with detailed imaging, was essential to identify this rare fistula and to prepare for therapeutic intervention at initial cardiac catheterization.  相似文献   
997.
The author's original approach to the early repair of cleft palate which consists in the use of the extended vomer flap is presented. The evolution of primary procedure under the influence of the philosophy of Malek and Psaume and all additional improvements of the author are described and illustrated. The early results (up to 6 years) of 40 palatoplasties performed at the ages of 3-6 months are roughly evaluated and discussed.  相似文献   
998.
Seven patients with Parkinson's disease who experienced severe motor fluctuations in response to levodopa were studied in detail with relation to the effect of dietary protein on their motor function. The levodopa dose for each patient was not changed during the period of study, and no other antiparkinsonian drugs were used. Regular and high-protein diets resulted in a marked elevation in the plasma concentrations of large neutral amino acids (LNAAs) that are known to compete with levodopa for transport across the blood-brain barrier. Despite elevated plasma levodopa levels, all patients with elevated LNAA levels experienced parkinsonian symptoms. When the amino acid level dropped while plasma levodopa levels were elevated, patients experienced relief of these symptoms. On a low-protein diet, LNAA levels remained low and all patients were consistently dyskinetic throughout the day, even though the mean plasma levodopa levels were somewhat lower than when the patients consumed a high-protein diet. A redistribution diet that is virtually protein free until supper and then unrestricted until bedtime is tolerated by patients because this simple manipulation permits near-normal daytime motor function.  相似文献   
999.
1000.
This article documents a patient with lung carcinoma that produced three oncofetal antigens including alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and human chorionic gonadotropin (hCG). Serum AFP, CEA, and hCG-beta-subunit were extremely high--118,000 ng/ml, 133 ng/ml and 0.9 ng/ml, respectively. Immunohistochemical staining of these tumor markers revealed that these proteins were present in different cells. The pattern of lectin affinity electrophoresis of AFP resembled that of hepatocellular carcinoma. Also investigated was the reactivity of serum CEA to monoclonal antibodies against peptide or sugar moieties. Serum CEA values measured by antipeptide monoclonal antibodies were higher than those measured by antisugar monoclonal antibodies. The demonstration of AFP, CEA, and hCG in different tumor cells suggests that three genomes were not reactivated together in a cell, and the lung carcinoma probably consisted of at least three clones of cancer cells with different phenotypes.  相似文献   
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