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21.
Fifty-four specimens from patients undergoing radical prostatectomy for clinically confined prostate cancer between 1983 and 1987 were reviewed to determine the potential for flow cytometric (FCM) analysis of DNA ploidy and replication rate to predict disease recurrence. Each specimen was deparaffinized for FCM analysis and the pathology slides were reviewed by a single pathologist. FCM characteristics were correlated with pathological grade and stage, and both were correlated with disease status. In this series of patients, routine FCM analysis of DNA ploidy and replication rate failed to significantly enhance the ability of standard histopathological grading to predict disease recurrence in patients having clinically localized prostate cancer. Aneuploid tumors pathologically confined to the prostate did not appear to negatively affect prognosis. 相似文献
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Cross-correlation and autocorrelation histograms were constructed with the aim of studying correlated spike activity of neurons
in the visual and sensorimotor regions of both hemispheres of the rabbit brain before and after stimulation of the right and
left lateral hypothalamic regions, which generates food-motivated responses. Stimulation of the left hypothalamus produced
larger rearrangements in correlated neuron firing than stimulation of the right hypothalamus. Stimulation of the left hypothalamus,
unlike that of the right hypothalamus, was followed by significant increases in the numbers of pairs of left hemisphere neocortical
neurons with linked activity, and also induced the sequential firing of neurons in a particular defined order: sensorimotor
cortex cells fired first, followed by visual cortex neurons after delays of up to 120 msec. It is concluded that cortical
interhemisphere asymmetry in conditions of hunger is associated with nonuniform functioning of the right and left lateral
hypothalamic regions.
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow. Translated from Fiziologicheskii
Zhurnal Vysshei Nervnoi Deyatel'nosti, Vol. 46, No. 6, pp. 1068–1075, November–December, 1996. 相似文献
24.
The influence of seven disinfectants on the dimensional stability of a base plate wax, Tenax, was studied. Two methods for treatment were tested - immersion for one hour and spraying respectively. After spraying no significant influence on the wax could be established and after immersion four of the seven disinfectants, including Cidex and K-644, likewise had no significant influence on the dimensional stability. The wax specimens did not show any significant weight increase (less than one per cent) after immersion for four days but in four disinfectant solutions the surface properties of the wax specimens had changed showing that active components of the disinfectants were absorbed into or adsorbed on the wax surface. 相似文献
25.
Lundin Pål D. P. Lundin Stefan Olsson Håkan Karlsson Börje W. Weström Björn R. Pierzynowski Stefan G. 《Pharmaceutical research》1995,12(10):1478-1482
Purpose. The present investigation was done to study the intestinal absorption of three oxytocin peptide analogues and to elucidate the role of pancreatic juice on their absorption.
Methods. In conscious chronically catheterized pigs (6–8 weeks of age) plasma concentration of the peptides, [Mpa1, D-Tyr(Ethyl)2, Thr4, Orn8]-oxytocin (F314), [Mpa1, D-Tyr(Ethyl)2, Val4, D-Arg8]-oxytocin (CAT), and [Mpa1, D-Tyr(Ethyl)2, Thr4, Orn8, desGly9, carba6]-oxytocin (F327) after intraduodenal administration, during presence or diversion of the pancreatic juice via a pancreatic duct catheter, were determined by radioimmunoassay. The stability of the peptides to degradation was determined in vitro by incubation with activated pancreatic juice, chymotrypsin or trypsin, followed by reversed phase HPLC analyses.
Results. All peptides were absorbed with a bioavailability of about 0.5% in the presence of pancreatic juice, but increased to 1.0%, 2.1%, and 13.5% for F314, CAT, and F327, respectively, when the pancreatic juice was diverted from the intestine. After incubation with pancreatic juice 95% of F314, 98% of F327, and 100% of CAT was found intact. When incubated with trypsin CAT remained intact while F314 and F327 were degraded by 54% and 46%, respectively. Incubation with purified chymotrypsin did not degrade the test peptides.
Conclusions. The results indicate that the increased absorption of peptides observed under conditions of diverted pancreatic juice cannot only be explained by the absence of pancreatic enzymes, but also by changed absorptive properties in the gastrointestinal tract. 相似文献
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Bobby Tingstedt Elinor Bexe-Lindskog Mats Ekelund Roland Andersson 《Acta chirurgica》2002,168(11):579-582
OBJECTIVE: To evaluate the outcome of patients treated for appendiceal abscess, and managed either conservatively or surgically, and to describe the short and long-term outcome as well as incidence of interval appendicectomy in those treated conservatively. DESIGN: Retrospective study. SETTING: University hospital, Sweden. PATIENTS: Ninety-three patients with the diagnosis of appendiceal abscess, 50 treated conservatively and 43 who were operated on, with a mean age of 46 (14-93) years. Mean (range) follow-up for patients operated on was 65 (11-135) and for those treated conservatively 66 (6-136) months. MAIN OUTCOME MEASURES: Course of acute disease, recorded complications, recurrence of appendicitis and incidence of interval appendicectomy during follow-up. RESULTS: The duration of pain before admission was 4 (0.5-82) days for those operated on and 7 (2-60) days for those treated conservatively. A palpable mass was more common in the conservatively managed group. Complications were common among patients who were operated on. No interval appendicectomies were done during the second half of the study period. 4 of the patients treated conservatively (8%) had an underlying tumour diagnosed at follow-up. CONCLUSIONS: Operative management of patients with appendiceal masses seems to be associated with a high risk of postoperative complications and the risk of a more extensive surgical procedure. If possible, a conservative approach should be advocated. Because of inaccurate radiological imaging during the acute phase and the risk of an underlying malignancy, routine follow-up is necessary. Routine interval appendicectomy cannot be recommended. 相似文献
29.
Inhibition of tissue factor surface expression in human peripheral blood monocytes exposed to cytokines 总被引:1,自引:0,他引:1
Interleukin (IL)-4, IL-10, IL-13 and transforming growth factor beta (TGF-β) are known to regulate several monocyte functions, including inhibition of the synthesis of different cytokines. Using quantitative RT-PCR and flow cytometry analysis we investigated the effects of these cytokines on bacterial lipopolysaccharide (LPS)-induced tissue factor (TF) expression in human monocytes. The effects of IL-4 and IL-10 on monocyte chemoattractant protein-1 (MCP-1)- and C-reactive protein (CRP)-induced TF expression were also studied. A direct comparison revealed that IL-4, IL-10 and IL-13 all down-regulated LPS-induced TF expression in a concentration-dependent manner without the need for priming. In contrast, TGF-β required 4 h of priming to inhibit TF expression induced by LPS. IL-10 was the most powerful inhibitor, causing almost complete inhibition at 5 ng/ml. IL-4 and IL-13 exhibited a significantly lower inhibitory capacity even at concentrations of 100 ng/ml. IL-4 and IL-10 showed similar concentration-dependent inhibition of MCP-1- and CRP-induced TF expression. We also showed that the regulatory effect of the interleukins occurred at the mRNA level. In vivo , these inhibitory cytokines may play an important regulatory role in preventing thrombosis. IL-10, in particular, may be a possible candidate as a TF-preventing drug. 相似文献
30.
In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO‐blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100%(TiO‐blasted) vs 95.3%(machined), P =0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 tvues of implant after 2 years of loading, 0.04 (0.82) mm, P >0.30. 相似文献