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71.
The role of the ethanol training dose on the ability of the selective 5-HT1 agonist TFMPP (m-trifluoromethylphenylpiperazine) to produce ethanol-like discriminative stimulus effects was evaluated in three groups of rats trained to discriminate 1.0 g/kg (n=5), 1.5 g/kg (n=6) or 2.0 g/kg (n=7) ethanol (IG) from water using a two-lever procedure with food reinforcement available under a fixed ratio 20 (FR 20) schedule. Ethanol generalization gradients were comparable in the three groups, indicating few potency differences in the ethanol stimulus across training dose. However, the ability of TFMPP (0.1–1.7 mg/kg; IP) to substitute for ethanol was dependent on the training dose. TFMPP resulted in partial substitution in the 1.0 g/kg group, complete substitution for 1.5 g/kg group and no substitution in the 2.0 g/kg ethanol training group. The results indicate a serotonergic component to the discriminative stimulus effects of an intermediate dose of ethanol that is not prominent as the dose of ethanol is raised. These data add further support for the hypothesis that ethanol produces a mixed discriminative cue, the components of which are not uniformly amplified when the dose of ethanol is increased. 相似文献
72.
Parental and professional responses to questionnaires evaluating a paediatric disability service are reported and the viability of auditing structural, process, and outcome aspects of clinical practice are discussed. Expectations of waiting time to first appointment (met for only 52% of consumers) illustrate structural issues. Process issues are reflected in consumer reactions to outreach work (for example, 94% of parents and 84% of professionals found this supportive). Outcome measures such as consumer satisfaction with the service (76% of consumers reported being 'very satisfied' and 20% 'fairly satisfied') suggest that service aims are being met. Good concurrence of service aims with consumer needs is indicated by parental reasons for referral (for example, 75% for diagnostic help, 73% for a better understanding of the disorder, 88% for practical help), referrers' reasons (for example, 55% for a second diagnostic opinion, 45% due to lack of local expertise), and reports from most other professionals involved with the case that a similar service was not provided locally. 相似文献
73.
E Grant E Turney M Bartlett C Winbon H D Peterson 《The Journal of burn care & rehabilitation》1992,13(6):703-707
The "Learn Not to Burn" prevention program is a burn prevention curriculum sponsored by the North Carolina Jaycee Burn Center, the State Department of Public Instruction, and the North Carolina Department of Insurance Fire and Rescue Division. The goal of the program is to reduce burn-related deaths and injuries in North Carolina through burn prevention education by making the "Learn Not to Burn" curriculum available to primary school children across the state at no cost to the schools. The curriculum instrument is a reusable notebook that provides a means for teachers to integrate burn prevention into regular class subject areas. At the time of initiation of this study approximately 70% of the school systems in North Carolina had been provided with the "Learn Not to Burn" curriculum. 相似文献
74.
M E McNaughton T L Patterson M R Irwin I Grant 《The Journal of nervous and mental disease》1992,180(8):491-497
We evaluated the relationship between life events, social support, coping, and depression in 27 male inpatients meeting the requirements for Research Diagnostic Criteria major depressive disorder and in 35 age- and sex-matched nonpatients. Overall, the hospitalized depressed patients reported significantly more events and difficulties than did the controls, but this difference in statistical significance disappeared after excluding from analysis "non-independent" happenings which could have been brought on by depression. More hospitalized depressed patients (23 of 27, or 85%) than controls (8 of 35, or 22.9%) experienced markedly threatening events and difficulties ("marked adversities") in the 6 months before their interview. The depressed group also reported having significantly fewer social supports, being less satisfied with the emotional component of this support, and using more emotion-focused coping than the controls. A discriminant analysis predicted depressive status from a combination of marked adversities, reduced number of social supports, and greater use of emotion-focused coping. The results indicate that the relationship of life events to depression is complex. The excess number of events might be partly a product of dysfunctional behavior that "produces" depression-related events which might, in turn, exacerbate depression; simultaneously, patients are more likely to experience highly adverse events which might precipitate the depression in the first place. Reduced social supports and the use of emotion-focused coping appear to also be associated with hospitalization for major depression. 相似文献
75.
Pancreatic pseudotumor in pancreas divisum: CT characteristics 总被引:1,自引:0,他引:1
P M Silverman L McVay R K Zeman B S Garra E G Grant M H Jaffe 《Journal of computer assisted tomography》1989,13(1):140-141
We report a case in which a focally spared area of pancreatic tissue in a gland otherwise replaced by fat created a "pseudomass" mimicking neoplasm on sonography and CT. The "pseudomass" appearance was related to the anomalous ductal anatomy in pancreas divisum. The spared area of pancreas creating a "pseudomass" was drained by the dorsal duct and the remainder of the pancreas that had undergone relative fatty replacement was drained by the ventral duct. 相似文献
76.
Ryuichi Yatani Taizo Shiraishi Kaneyoshi Akazaki Takuji Hayashi Lance K. Heilbrun Grant N. Stemmermann 《Virchows Archiv : an international journal of pathology》1986,409(4):395-405
Summary The histological grades of prostatic carcinoma, as defined by Gleason, were correlated with three methods of morphometry in 254 step-sectioned prostates obtained at autopsy. The variables studied were 1) the number of tumours in each prostate; 2) bilaterality and 3) tumour volume. Each characteristic yielded a statistically significant correlation with histological grade. The strongest correlations were obtained using tumour volume. These autopsy studied help to explain the inconsistent results obtained from morphometric analyses of surgical material, and lend support to the Gleason system as a means of predicting tumour behavior.Supported in part by research contracts PH 64-10, NCI-72-3213, N01-CP-53521; Grant R01-CA-33644; and the Grant-in-Aid for Cancer Research (33) from the Ministry of Health and Welfare 相似文献
77.
Heparin-binding fragments of fibronectin are potent inhibitors of endothelial cell growth. 总被引:7,自引:1,他引:7 下载免费PDF全文
G. A. Homandberg J. E. Williams D. Grant B. Schumacher R. Eisenstein 《The American journal of pathology》1985,120(3):327-332
Two heparin-binding proteolytic fragments of fibronectin--an amino-terminal 29-kd segment and a carboxyl-terminal 40-kd segment-are apparently specific, potent inhibitors of the growth of cultured bovine aortic endothelial cells and inhibit growth in a reversible, dose-dependent manner. In contrast, native fibronectin at higher dosages neither inhibits nor interferes with the effects of the 29-kd fragment. The data, therefore, suggest that fibronectin fragments may participate in the regulation of vascular growth. 相似文献
78.
79.
Characterization of the Interaction between Yersinia enterocolitica Biotype 1A and Phagocytes and Epithelial Cells In Vitro 下载免费PDF全文
Yersinia enterocolitica strains of biotype 1A are increasingly being recognized as etiological agents of gastroenteritis. However, the mechanisms by which these bacteria cause disease differ from those of highly invasive, virulence plasmid-bearing Y. enterocolitica strains and are poorly understood. We have investigated several biotype 1A strains of diverse origin for their ability to resist killing by professional phagocytes. All strains were rapidly killed by polymorphonuclear leukocytes but persisted within macrophages (activated with gamma interferon) to a significantly greater extent (survival = 40.5% +/- 17.4%) than did Escherichia coli HB101 (9.3% +/- 0.7%; P = 0.0001). Strains isolated from symptomatic patients were significantly more resistant to killing by macrophages (survival = 48.9% +/- 19.5%) than were strains obtained from food or the environment (survival = 32.1% +/- 10.3%; P = 0.04). Some strains which had been ingested by macrophages or HEp-2 epithelial cells showed a tendency to reemerge into the tissue culture medium over a period lasting several hours. This phenomenon, which we termed "escape," was observed in 14 of 15 strains of clinical origin but in only 3 of 12 nonclinical isolates (P = 0.001). The capacity of bacteria to escape from cells was not directly related to their invasive ability. To determine if escape was due to host cell lysis, we used a variety of techniques, including lactate dehydrogenase release, trypan blue exclusion, and examination of infected cells by light and electron microscopy, to measure cell viability and lysis. These studies established that biotype 1A Y. enterocolitica strains were able to escape from macrophages or epithelial cells without causing detectable cytolysis, suggesting that escape was achieved by a process resembling exocytosis. The observations that biotype 1A Y. enterocolitica strains of clinical origin are significantly more resistant to killing by macrophages and significantly more likely to escape from host cells than are strains of nonclinical origin suggest that these properties may account for the virulence of these bacteria. 相似文献
80.
Broiler chickens as potential source of Campylobacter infections in humans. 总被引:23,自引:8,他引:23 下载免费PDF全文
Of 46 broiler chickens from a live poultry market in New York City, 38 (83%) harbored Campylobacter fetus subsp. jejuni in their rectal flora. The observed mean number of C. fetus per g of feces was 4.4 x 10(6). The organisms survived in the feces for at least 96 h at 4 degrees C whether stored in the gut or transferred to a vial. The best survival medium for pure cultures of C. fetus subsp.jejuni was heart infusion broth supplemented with sterile blood and kept in a microaerophilic atmosphere. 相似文献