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81.
H Rosdahl AC Samuelsson U Ungerstedt J Henriksson 《Canadian Metallurgical Quarterly》1998,163(4):349-360
Epidermal growth factor (EGF) has been considered to be a candidate for neurotrophic factors on the basis of the results of several in vitro studies. However, the in vivo effect of EGF on ischemic neurons as well as its mechanism of action have not been fully understood. In the present in vivo study using a gerbil ischemia-model, we examined the effects of EGF on ischemia-induced learning disability and hippocampal CA1 neuron damage. Cerebroventricular infusion of EGF (24 or 120 ng/d) for 7 days to gerbils starting 2 hours before or immediately after transient forebrain ischemia caused a significant prolongation of response latency time in a passive avoidance task in comparison with the response latency of vehicle-treated ischemic animals. Subsequent histologic examinations showed that EGF effectively prevented delayed neuronal death of CA1 neurons in the stratum pyramidale and preserved synapses intact within the strata moleculare, radiatum, and oriens of the hippocampal CA1 region. In situ detection of DNA fragmentation (TUNEL staining) revealed that ischemic animals infused with EGF contained fewer TUNEL-positive neurons in the hippocampal CA1 field than those infused with vehicle alone at the seventh day after ischemia. In primary hippocampal cultures, EGF (0.048 to 6.0 ng/mL) extended the survival of cultured neurons, facilitated neurite outgrowth, and prevented neuronal damage caused by the hydroxyl radical-producing agent FeSO4 and by the peroxynitrite-producing agent 3-morpholinosydnonimine in a dose-dependent manner. Moreover, EGF significantly attenuated FeSO4-induced lipid peroxidation of cultured neurons. These findings suggest that EGF has a neuroprotective effect on ischemic hippocampal neurons in vivo possibly through inhibition of free radical neurotoxicity and lipid peroxidation. 相似文献
82.
OP Rosaeg M Bell NJ Cicutti KC Dennehy AC Lui B Krepski 《Canadian Metallurgical Quarterly》1998,23(6):575-579
BACKGROUND: The main purpose of the reconstruction of the cranium is the protection of the brain. Besides we have to consider important functional and aesthetic necessities in order to achieve satisfactory results. METHODS: Thirty-six clinical cases, operated from November 1991 to June 1996, in which the reconstruction of the cranial vault is carried out by a polymethylmethacrylate acrylic resin are analysed. The causes and locations of the most common bone defects and the main indications for reconstruction are examined. While the repair of the osseous gaps caused by neoplasms is immediate, in the traumatic occurrences, in order to reduce the probability of infectious complications, an average time of 11 months elapsed from the first operation. The surgical technique, with slightest alterations, is the same in all the presented cases, preparing the acrylic resin straight on the operating table. The resin, moulded and adapted to the defect until its complete hardening, presents, thanks to its properties, manifold advantages (and few real disadvantages). RESULTS: The results, in terms of complications, are very satisfactory, with an infectious rate of 2.7%. Besides, in one third of the patients, a considerable clinical improvement after the repair has been observed. CONCLUSIONS: According to personal experience, it is possible to affirm that polymethylmethacrylate, with its remarkable plasticity and stability in time, can always guarantee a satisfactory functional and aesthetic result. 相似文献
83.
NP Pereira TM Monteiro AC Freitas EJ Barreiro AL Miranda 《Canadian Metallurgical Quarterly》1998,137(3):82-86
A new series 5-thio aryl pyrazole derivatives were proposed aiming analgesic activity. In this work, 8 new compounds of this class were synthesized using usual synthetic methodology, having as key intermediate the 3-methyl-4-nitro-5-chloropyrazole-1-phenyl derivative and subsequent reaction with several nucleophiles sulfides. Pharmacological evaluation of this series showed analgesic activity in the some extent in especially for 5-(4-bromophenyl)-thio-3-methyl-4-nitro-1-phenylpyrazole which was the most potent in this series, presenting an analgesic action comparable to that show by dipyrone. 相似文献
84.
Experimental occlusal interferences. Part IV. Mandibular rotations induced by a pliable interference
In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminum shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0 degree) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4 degree) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4 degree) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3 degree) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short- and long-term detrimental effects. 相似文献
85.
86.
PG McNally NT Raymond ML Burden PR Burton JL Botha PG Swift AC Burden JR Hearnshaw 《Canadian Metallurgical Quarterly》1995,12(11):961-966
The relative risk of death by calendar date of diagnosis was investigated in a population-based incident cohort of 845 (463 males:382 females) IDDM diagnosed in Leicestershire before the age of 17 years between 1940 and 1989. The mortality status of 844 (99.9%) patients was determined as of the 31 December 1991, representing 14,346 person-years of risk. Trends in relative risk of death were investigated using Cox proportional hazards modelling for within cohort comparisons and age/sex and calendar time adjusted standardized mortality ratios (SMR) using generalized linear modelling for external comparisons. Median age at diagnosis was 10 years (range 3 months to 16 years); median duration of diabetes 15 years (range 1-51 years). Forty-four patients had died (5.2%; median age at death 31 years, range 11-51 years). A further four patients died at presentation (within 24 h) from ketoacidosis and are excluded from all analyses. Calendar date of diagnosis was found to be an important predictor of mortality. Adjusting for attained age there was evidence of a decline in relative risk of death with calendar date of diagnosis of 3.4% (95% CI, 0.005-6.9%) per annum, equivalent to a 32% fall per decade (95% CI, 5-51%), or 84% (95% CI, 21-97) from 1940 to 1989. The data are consistent with a large fall in mortality between the 1940s and 1950s representing over 50% of the total reduction in mortality between 1940 and 1991. Neither sex nor age at diagnosis were significant predictors of mortality. Over the study period 1940-89 the SMR (male and female combined) fell from 981 (541-1556) to 238 (60-953) relative to the general population. This population-based study shows that the prognosis for Type 1 (insulin-dependent) diabetes mellitus has improved markedly over the period 1940-1991. 相似文献
87.
AC Buenafe H Offner M Machnicki H Elerding K Adlard R Jacobs AA Vandenbark G Adamus 《Canadian Metallurgical Quarterly》1998,161(4):2052-2059
T cells infiltrating the iris/ciliary body of Lewis rats with anterior uveitis (AU) that had been induced by myelin basic protein (MBP) immunization were previously found to share surface markers common to the T cells that cause experimental autoimmune encephalomyelitis (EAE). To determine whether these AU-associated T cells are in fact the same as those that infiltrate the central nervous system to cause EAE, we examined TCR V gene expression in T cells infiltrating the anterior chamber in rats with AU. As with EAE, we found a biased expression of Vbeta8.2 and Valpha2 in the iris/ciliary body and, although one would expect an influx of nonspecific inflammatory T cells, these biases were still evident at the peak of AU. An analysis of the TCR Vbeta8.2 and Valpha2 sequences derived from the iris/ciliary body demonstrated the presence of the same complementarity determining region 3 motifs found in MBP-specific T cells that are pathogenic for EAE and found in T cells derived from the central nervous system of rats with EAE. Finally, T cells isolated from the iris/ciliary body of rats with AU were found to proliferate in a specific fashion to MBP Ags. Thus, it appears that MBP-specific T cells are pathogenic for AU as well as EAE in the Lewis rat. In addition, the long-term presence of this highly restricted MBP response in the iris/ciliary body indicates that distinct immunoregulatory mechanisms exist in the environment of the eye. This provides an interesting model with which to address questions pertaining to the nature of T cells infiltrating the eye and their regulation during EAE and other systemic diseases. 相似文献
88.
In a Danish population-based non-Hodgkin's lymphoma registry, 2687 newly diagnosed patients were registered from 1983 to 1992. 39 had testicular involvement (TL) (incidence 0.26/10(5)/year). Median age was 71 years. 24 cases had localised and 15 had disseminated disease. Histologically, all cases were diffuse (65% diffuse centroblastic type). Of the 27 tested, 11% were of T- and 89% of B-immunophenotype. In localised cases, where surgery was supplemented by combination chemotherapy (CCT), the relapse rate was 15.4%. The relapse rate for cases with localised disease treated with other regimens (orchiectomy and/or radiotherapy) was 63.6% (P < 0.05). Median relapse-free survival was 28 and 14 months, respectively. Overall 5-year survival for all cases was 17%. Adverse prognostic factors at the univariate level were stage IV, constitutional symptoms, serum lactic dehydrogenase elevation and performance score (WHO 3-4). It is suggested that the treatment of stage IE/IIE TL should include early CCT and CNS prophylaxis. 相似文献
89.
A hyperdynamic circulatory state with elevated cardiac output, decreased peripheral vascular resistance, and sodium retention occurs in patients with portal cirrhosis. Surgical portal-systemic shunts and transjugular intrahepatic portal-systemic shunts (TIPS) have been shown to worsen the high-output state in these patients. However, clinical evidence of high-output congestive heart failure has been reported only rarely to complicate cirrhosis. We describe a patient who developed high-output congestive heart failure with markedly elevated filling pressures after TIPS and had complete resolution of heart failure after liver transplantation. 相似文献
90.
This study was designed to examine whether cyclosporine (CyA) acts on the endocrine system by modifying the pulsatile secretion pattern of prolactin and LH. Both pituitary-grafted and sham-operated rats were submitted to a subcutaneous vehicle or CyA (5 mg/kg) treatment daily for 10 days beginning on the day of surgery. Pituitary grafting and/or CyA administration changed the pulsatile pattern of prolactin observed in sham-operated animals. The mean values of serum prolactin were significantly increased by pituitary grafting and the treatment with CyA further increased them. The mean half-life of prolactin was significantly increased in pituitary-grafted rats and was not changed by CyA administration, although it was decreased in sham-operated rats. The frequency of prolactin pulses was significantly decreased in pituitary-grafted as compared to sham-operated controls and was not further modified by CyA administration. However, in sham-operated rats a significant decrease of this parameter was observed. Duration of the prolactin peaks was significantly increased by pituitary grafting, and was not modified by CyA administration in any of the groups studied. The absolute amplitude of the prolactin peaks was significantly increased in pituitary-grafted as compared to sham-operated animals, and the treatment with CyA further increased this parameter in both groups. Mean values of LH were significantly increased in pituitary-grafted as compared to control rats. CyA administration significantly increased LH levels in sham-operated rats and decreased them in pituitary-grafted animals. The mean half-life, the pulse frequency and the duration of LH peaks were not modified by either pituitary grafting or CyA administration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献