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51.
Fine, long, fibrous septa were observed as a late change developing in the acinar zone III of the liver of rats experimentally infected with the helminth Capillaria hepatica. Hepatic septal fibrosis begun 30 days after inoculation of embryonated eggs into the stomach of rats and became clearly evident from the 40th day onwards. Experimental observation was undertaken for 170 days. Septal fibrosis increased progressively with time and was most marked when the parasitic nodules formed around larvae, disintegrating worms and eggs were involving. Septal fibrosis of the liver has not been previously recognized as a manifestation of hepatic capillariasis. The presence of sequestered parasite antigens, probably being slowly released within the liver, appears to be a major factor in the pathogenesis of hepatic septal fibrosis observed in rats with C. hepatica infection. 相似文献
52.
ZA Saeed 《Canadian Metallurgical Quarterly》1996,28(7):559-564
BACKGROUND AND STUDY AIMS: Rubber-band ligation is superior to sclerotherapy, and is considered to be the endoscopic treatment of choice for bleeding varices. The single-shot mechanism of the ligation device generally used is inherently inefficient, and makes the procedure tedious. It also requires overtube placement, associated with discomfort and complications. This study describes the Saeed Six-Shooter, a multiple ligation device. PATIENTS AND METHODS: Twenty-seven consecutive patients with variceal bleeding were prospectively studied. After initial endoscopic ligation, subsequent sessions were every 7-10 days. The parameters studied were the ease of use, the ability to control active bleeding and eradicate varices, survival, and complications. RESULTS: Active bleeding was controlled in all seven (100%) patients. Esophageal varices were eradicated in 70% (3.2 +/- 1.2 sessions), and gastric varices in 88% of patients (2 +/- 1.2 sessions). Five patients re-bled, two from esophageal varices, two from gastric varices, and one from treatment-induced ulcer. There were four deaths, none due to exsanguination. A single complication, esophageal stricture, resolved with balloon dilation. Intubation was no more difficult with the endoscope loaded with the Six-Shooter than with the endoscope alone (P > 0.3). Six ligations were performed in 39% of cases within 60 seconds, and in 74% of cases within 90 seconds. For gastric varices, the device was effectively used with the endoscope retroflexed. CONCLUSIONS: The Saeed Six-Shooter is a safe and efficient instrument for the endoscopic ligation of varices, and has overcome the limitations of the single-shot ligator. 相似文献
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54.
Utilization of psychiatric in-patient care among 537 new patients was studied in the Department of Psychiatry in Oulu, Finland, during a 3-year follow-up period. Hospitalization during the second and third years of the follow-up was predicted by hospitalization and number of emergency out-patient contacts during the first year of the study, diagnosis of functional psychosis or personality disorder, and previous in-patient care. In total, 5% of the cohort fulfilled our criteria for 'revolving-door' patients. The 'revolving-door' phenomenon was associated with in-patient care at the first contact with the psychiatric services and diagnosis of psychosis or personality disorder. In total, 2% of the cohort became long-stay hospital patients, and this was predicted by psychosis diagnosis. The clinical implications of these findings are that increased attention should be paid to the first assessment of new patients and to the interaction between psychiatric services and patients during the first year of care. 相似文献
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57.
P. Vicente A. Raymond M. Kamal Saadi B. Couzinet M. Kubisa W. Zawadzki B. Etienne 《Solid-state electronics》1996,40(1-8):109-112
Interband photoluminescence from asymmetric modulation-doped GaAs---GaAlAs quantum wells in the presence of a magnetic field has been investigated. The free-carrier Landau level excitations as well as transitions between magneto-donor and free hole states have been observed. Experiments with tilted magnetic field provide strong evidence for the existence of conduction electrons bound to ionized magneto-acceptors, characterized by discrete energies above the conduction band Landau levels. The observations are compared with the theory. 相似文献
58.
PURPOSE: Gabapentin (GBP), lamotrigine (LTG), tiagabine (TGB), topiramate (TPM), vigabatrin (VGB), and zonisamide (ZNS) are all in use as "add-on" treatment for patients with refractory epilepsy. There have been no comparative randomized controlled trials allowing an evidence-based choice between these drugs. We report a series of meta-analyses of randomized placebo-controlled add-on trials in which these drugs have been tested in patients with partial epilepsy. This work provides an estimate of each drug's efficacy and tolerability compared with placebo. These estimates are compared across drugs to give broad estimates of comparative efficacy and tolerability. METHODS: Trial reports were found by searching Medline, by searching through journals by hand, and by contacting the pharmaceutical industry. The outcomes chosen were the proportion of patients who (a) have a > or = 50% reduction in seizure frequency (50% responders); (b) withdrew from the study (any reason); or (c) reported the following side effects: ataxia, dizziness, fatigue, nausea, or somnolence. Overall odds ratio (OR) with 95% confidence intervals (CIs; 50% responders) or 99% CIs; side effects) were calculated. RESULTS: Twenty-nine trials were included, representing 4,091 randomized patients. The ORs for 50% response (95% CI) were GBP, 2.29 (1.53-3.43); LTG, 2.32 (1.47-3.68); TGB, 3.03 (2.01-4.58); TPM, 4.07 (2.87-5.78); VGB, 3.67 (2.44-5.51); and ZNS, 2.7 (1.36-4.47). ORs for discontinuation were GBP, 1.36 (0.75-2.49); LTG, 1.19 (0.79-1.79); TGB, 1.81 (1.21-2.70); TPM, 2.56 (1.64-4.00); VGB, 2.58 (126-5.27); and ZNS, 4.23 (1.71-10.49). CONCLUSIONS: We have clear evidence that each of these drugs is better than placebo at preventing seizures. When results are compared across drugs, the confidence intervals overlap, and we have no conclusive evidence of differences in efficacy or tolerability. Despite this, the agent that appears most effective may be twice as effective as the agent that appears least effective, and the agent that appears most likely to cause discontinuation may be 4 times more likely to do so than the treatment that appears least likely to do so. Comparative randomized studies are needed further to evaluate these drugs. 相似文献
59.
The effect of various metal additives on the catalytic performance of carbon during the selective reduction of NO with methanol has been studied in the absence and in the presence of gas-phase oxygen. The mechanism of this reaction in the use of carbon-supported catalysts was studied by means of in situ FTIR combined with the measurements of catalytic activity. In the absence of oxygen, NO is adsorbed in a very small amount on the surface of carbon. The reaction of NO with the products of the methanol decomposition, results in the formation of adsorbed isocyanate (NCO) species at 2229 cm−1. Formation of gaseous NH3 as a product of the reaction between NO and methanol was observed. Oxygen-containing surface functional groups of carbon effectively promotes the reduction of NO with methanol. IR spectroscopic results of this study show that in the presence of O2 nitric oxide is catalytically oxidized to nitrogen dioxide, which is chemisorbed on the surface of carbon. The surface nitrogen species were identified by FTIR spectroscopy. 相似文献
60.
Thermal stability improvement of hopcalite catalyst 总被引:1,自引:0,他引:1
The properties of hopcalite in alumina matrix formed by rehydration of transition aluminas have been investigated in comparison with conventional hopcalite catalyst. By using X-ray diffraction, thermal analysis and activity measurements in combustion ofn-butane and air mixture it was found that the presence of alumina matrix leads to improvement of thermal stability at elevated temperatures and to limitation of spinel phase recrystallization. The modified catalyst was found to show much higher activity after thermal treatment at temperatures above 773 K than pure hopcalite at the same conditions. 相似文献