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91.
In a first phase of this investigation, a validation of our elevated plus-maze apparatus was performed in male Sprague-Dawley rats by testing anxiety response at various ambient light intensities (200, 30, 10 and 2.5 lux), as well as the effects of diazepam treatment (0.5 and 1.0 mg/kg, i.p. at 30 lux). Anxiety responses were found to decrease with decreasing light intensity and to be attenuated by diazepam treatment. Subsequently, a separate set of rats was exposed to 2.45 GHz EMFs (2 micros pulse width, 500 pulses per second, whole-body and time averaged of SAR 0.6 W/kg +/-2 dB, brain-averaged SAR of 0.9 W/kg +/-3 dB) for 45 min to assess whether EMF exposure altered anxiety responses in the same apparatus. As we made no a priori hypothesis on whether the effects would be anxiogenic or anxiolytic, part of the rats were tested under an ambient light intensity of 2.5 lux, the other one being tested at 30 lux. The low intensity level set the behavioural baseline for the detection of anxiogenic effects, while the higher one corresponded to the detection of anxiolytic effects. Sham-exposed and naive rats were used as controls. Whatever light intensity was used, EMF exposure failed to induce any significant effect on anxiety responses in the plus maze. The present experiment demonstrates that exposure to EMFs, which was previously found to increase the number of benzodiazepine receptors in the rat cortex [Lai H, Carino MA, Horita A, Guy AW. Single vs. repeated microwave exposure: effects on benzodiazepine receptors in the brain of the rat. Bioelectromagnetics 1992;13(1):57-66], does not alter anxiety responses assessed in the elevated plus maze.  相似文献   
92.
Correlation of MDR 1 expression and CA 125 in ovarian cancer   总被引:1,自引:0,他引:1  
BACKGROUND: The serum CA 125 marker is elevated in 80% of patients with ovarian adenocarcinoma. MDR 1 gene expression has been identified in a variety of tumor types and its expression has been correlated with multidrug resistance. Whether there is a correlation between CA 125 levels and MDR 1 expression has not been sufficiently investigated. Therefore, the aim of this study was to examine whether an association between serum CA 125 levels and MDR 1 expression exists. PATIENTS AND METHODS: Serum CA 125 levels were measured during the diagnosis of ovarian cancer. Fresh tumor specimens or ascitic fluid samples were studied for MDR 1 expression by the polymerase chain reaction method (PCR). RESULTS: Forty patients with ovarian cancer were studied, 34 (85%) of whom had elevated CA 125. Twenty-eight out of the 40 patients were tested for MDR 1 expression; 20 expressed the gene and 8 did not. The median level of CA 125 in specimens expressing the MDR1 gene was 327, and in specimens that did not it was 376. There was no correlation between the CA 125 levels and MDR 1 expression (p = 0.484). CONCLUSION: There does not seem to be an association between CA 125 levels and expression of the MDR1 gene in patients with ovarian cancer.  相似文献   
93.
The Delta Sxrb interval of the mouse Y chromosome is critical for spermatogenesis and expression of the male-specific minor transplantation antigen H-Y. Several genes have been mapped to this interval and each has a homologue on the X chromosome. Four, Zfy1 , Zfy2 , Ube1y and Dffry , are expressed specifically in the testis and their X homologues are not transcribed from the inactive X chromosome. A further two, Smcy and Uty , are ubiquitously expressed and their X homologues escape X-inactivation. Here we report the identification of another gene from this region of the mouse Y chromosome. It encodes the highly conserved eukaryotic translation initiation factor eIF-2gamma. In the mouse this gene is ubiquitously expressed, has an X chromosome homologue which maps close to Dmd and escapes X-inactivation. The coding regions of the X and Y genes show 86% nucleotide identity and encode putative products with 98% amino acid identity. In humans, the eIF-2gamma structural gene is located on the X chromosome at Xp21 and this also escapes X-inactivation. However, there is no evidence of a Y copy of this gene in humans. We have identified autosomal retroposons of eIF-2gamma in both humans and mice and an additional retroposon on the X chromosome in some mouse strains. Ark blot analysis of eutherian and metatherian genomic DNA indicates that X-Y homologues are present in all species tested except simian primates and kangaroo and that retroposons are common to a wide range of mammals. These results shed light on the evolution of X-Y homologous genes.   相似文献   
94.
In order to assess the diagnostic value of procalcitonin, 158 patients with febrile neutropenia from centres across Europe were studied. Patients with fever were diagnosed on the basis of either: (1) clinical, radiological and microbiological criteria; or (2) the procalcitonin value. In the latter case, concentrations of 0.5-1.0 ng/mL were considered diagnostic of localised infection, concentrations of 1.0-5.0 ng/mL of bacteraemia, and concentrations of > 5.0 ng/mL of severe sepsis. Procalcitonin and C-reactive protein were estimated daily in serum by immunochemiluminescence and nephelometry, respectively. Overall, the sensitivity (specificity) of procalcitonin for bacteraemia was 44.2% (64.3%) at concentrations of 1.0-5.0 ng/mL, and 83.3% (100%) for severe sepsis at concentrations of > 5.0 ng/mL. It was concluded that procalcitonin is a marker strongly suggestive of severe sepsis at concentrations of > 5.0 ng/mL. Estimated concentrations of < 0.5 ng/mL indicate that infection is unlikely, but it was observed that bacteraemia associated with coagulase-negative staphylococci may fail to elevate serum procalcitonin levels.  相似文献   
95.
BACKGROUND: National guidelines are rarely followed by immediate changein clinical behaviour. We present our experience of an activeeducational method for local development and implementationof a guideline. OBJECTIVE: To evaluate the effectiveness of a participative method fordeveloping local clinical guidelines. METHODS: A trial in a district of the effect of guideline developmentincorporating active participation of intended recipients onsubsequent relevant prescribing. It was carried out in WirralFamily Health Services Authority district (the Wirral peninsula)comprising 69 general practices covering a population of 345763. An exemplar guideline on ‘hypertension in the elderly’was developed by the method described. The principal recommendeddrug was bendrofluazide 2.5 mg once daily. The differences inprescribed daily doses (PDD) of bendrofluazide 2.5 mg tabletsper quarter per 1000 prescribing units (age-weighted population)between the intervention district and England as a whole wasmeasured. RESULTS: Comparison of the intervention district with England data demonstratesa median difference of 122.49 PDD before and 206.34 PDD afterguideline production, this change is statistically highly significant(Mann-Whitney two-tailed P < 0.0001; 95% CL = 36.51–104.77).Grouped regression analysis shows no significant difference(0.89) in slope gradients before guideline production (P = 0.35,95% CL = –3.97–5.76), but the difference in slopegradients after (12.95) is statistically highly significant(P < 0.0001; 95% CL = 8.17–17.73). The data suggeststhat the change in clinical behaviour persisted for at leasttwo years. CONCLUSION: Participation of intended recipient general practitioners andlocal specialists in the development of a guideline by an activeeducational method as described was followed by a favourablechange in clinical behaviour which persisted for at least twoyears. Keywords. Clinical guidelines, development, evaluation, implementation, participation.  相似文献   
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98.
There is increasing evidence that bcl6 and CD10 expression may be related to apoptosis and cell cycle progression. Therefore, 79 cases of de novo diffuse large B-cell lymphomas were studied for the expression of bcl6 and CD10 proteins in relation to 1) the apoptotic index; 2) the proliferation-associated proteins Ki67, cyclin A, and cyclin B1; and 3) the expression of the bcl2, p53, Rb, p16, and p27 proteins. Expression of bcl6, CD10, and bcl2 proteins was found in 54/79 (68%), 28/79 (35%), and 47/74 (63%) cases, respectively. The bcl6/CD10 patterns were as follows: bcl6+/CD10+ (26 cases, 32%), bcl6+/CD10- (28 cases, 33%), bcl6-/CD10- (23 cases, 31%), and bcl6-/CD10+ (2 cases, 4%). Significant positive correlations were found between bcl6/Ki67 (r =.328, P =.003), bcl6/cyclin A (r =.265, P =.018), bcl6/apoptotic index (r =.327, P =.010), CD10/Ki67 (r =.296, P =.008), and CD10/apoptotic index (r =.397, P =.001). In addition, high expression of bcl6 showed significant correlation with negative (null/low) bcl2 expression (chi(2) test, P =.002). The above findings indicate that increased expression of the bcl6 and CD10 proteins is associated with increased apoptosis and proliferation in diffuse large B-cell lymphomas. The association between increased bcl6 expression and enhanced apoptosis might be due, at least in part, to the null/low bcl2 expression because previous in vitro data showed that bcl6 overexpression induces apoptosis accompanied by bcl2 and bcl-xl downregulation. Moreover, significant correlation was found between increased apoptotic index and the bcl6+/CD10+ pattern (t test: P =.014, Mann-Whitney test: P =.046). This finding and the positive correlation of the apoptotic index with bcl6 and CD10 expression may be related to previous results showing that the expression of these proteins has favorable effects on the clinical outcome of diffuse large B-cell lymphomas.  相似文献   
99.
In attempt to investigate the stimulatory effect of Pseudomonas aeruginosa on innate immunity and to correlate it to its level of resistance to antimicrobials, 20 isolates were applied; 8 isolates were susceptible and 12 multidrug-resistant. Genetic diversity was defined by PFGE. Human monocytes of two healthy volunteers were in vitro stimulated by the isolates for the production of pro-inflammatory (TNF-alpha, IL-1beta, IL-6, IL-8 and IL-12) and anti-inflammatory cytokines (IL-10), of malondialdehyde and of procalcitonin. Cytokines were estimated by EIA, malondialdehyde by the thiobarbiturate assay and procalcitonin by an immunochemiluminometric assay. Survival of 48 Wistar rats was recorded after induction of sepsis by the intraperitoneal injection of three susceptible and three multidrug-resistant isolates. To test whether comparative effect of the latter isolates on survival correlates with any difference of monocyte-mediated release of pro-inflammatory mediators, monocytes of two rats were in vitro stimulated for the production of TNF-alpha and of malondialdehyde. In vitro stimulation of human monocytes by the susceptible isolates elicited elevated production of malondiadeheyde, of IL-1beta and of IL-6 compared to stimulation by multidrug-resistant isolates. Similar differences were found for TNF-alpha and IL-8, but they were not statistically significant. Production of IL-10 and IL-12 was not detected after stimulation with any isolate. Levels of procalcitonin were similar after induction with either susceptible or multidrug-resistant isolates. Mean survival of animals was 7.56, 21.80 and 55.20 h, respectively, after challenge by the susceptible isolates and 28.89, 61.8 and more than 120 h, respectively, after challenge by the multidrug-resistant isolates. Differences of survival were accompanied by greater rodent monocyte-release of TNF-alpha and malondialdehyde after stimulation by the susceptible isolates compared to multidrug-resistant ones. It is concluded that considerable differences are encountered on the stimulation of human monocytes by susceptible and resistant isolates of Pseudomonas aeruginosa. These results correlate with in vivo evidence and might influence decision on therapeutics.  相似文献   
100.
Three-month-old Long-Evans rats were subjected to intraseptal infusions of 0.8 microg of 192 IgG-saporin followed, 2 weeks later, by intrahippocampal suspension grafts containing fetal cells from the medial septum and the diagonal band of Broca. The suspensions were implanted in the dorsal or the ventral hippocampus. Sham-operated and lesion-only rats were used as controls. Between 18 and 32 weeks after grafting, all rats were tested in a water maze (using protocols placing emphasis on reference memory or on working memory) and an eight-arm radial maze. The lesion produced extensive cholinergic denervation of the hippocampus, as evidenced by reduced acetylcholinesterase-positivity and acetylcholine content. Depending upon their implantation site, the grafts restored an acetylcholinesterase-positive reinnervation pattern in either the dorsal or the ventral hippocampus. Nevertheless, the grafts failed to normalize the concentration of acetylcholine in either region. The cholinergic lesion impaired working memory performance in both the water maze and the radial maze. To a limited degree, reference memory was also altered. Grafts placed in the ventral hippocampus had no significant behavioral effect, whereas those placed in the dorsal hippocampus normalized working memory performance in the water maze. Our data show that infusion of 192 IgG-saporin into the septal region deprived the hippocampus of its cholinergic innervation and altered spatial working memory more consistently than spatial reference memory. Although the cholinergic nature of the graft-induced reinnervation remains to be established more clearly, these results further support the idea of a functional dissociation between the dorsal and the ventral hippocampus, the former being preferentially involved in spatial memory.  相似文献   
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