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31.
We previously found that a ventricular isovolumic pressure-time curve could be well fitted by the difference between two S-shaped logistic curves for the pressure rising and falling components, and called it "hybrid logistic" function: P(t)=A/[1+exp[-(4B/A)(t-C)]]-D/[1+exp[-(4E/D)(t-F)]]+G. We reported that the parameters of this hybrid logistic function are useful to characterize left ventricular contraction and relaxation comprehensively. In this study, we investigated how well this hybrid logistic function could fit the isometric twitch force-time curves of cross-circulated right ventricular papillary muscles of 7 dogs. This function precisely fitted the isometric force curves with correlation coefficients above 0.9996, much better than another fitting function (F(t)=C(t/A)(B)exp[1-(t/A)(B)]) proposed by Nwasokwa. The present results indicate that our hybrid logistic function can also reasonably express the canine right ventricular papillary muscle isometric twitch force-time curve. We suggest the possibility that the parameters of this hybrid logistic function are also useful to comprehensively characterize right ventricular papillary muscle twitch contraction and relaxation.  相似文献   
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BACKGROUND AND OBJECTIVE: To evaluate the adjunctive use of mitomycin-C (MMC) during trabeculotomy and trabeculectomy for eyes with high-risk congenital glaucoma. PATIENTS AND METHODS: A prospective, randomized, double-blind study was performed to compare the effect of a single, 4-minute intraoperative exposure to 0.2 mg/ml (group 1) or 0.4 mg/ml (group 2) of MMC on trabeculotomy with trabeculectomy in 16 high-risk cases (30 eyes) of congenital glaucoma. RESULTS: The preoperative and final postoperative intraocular pressures (IOPs) of the two groups did not differ significantly. At the final follow-up, IOP control (< 21 mm Hg) without medications was achieved in 60% of the eyes in group 1 and in 86.67% of the eyes in group 2 (P = 21). With medication, IOP control was achieved in 86.7% of the eyes of each group. In both groups, the rate of surgical failure was 13.3%. Avascular, thin, sharply demarcated blebs were noted in 33.3% of the eyes from group 1 and in 66.67% of those from group 2 (P = .14). Intraoperative and postoperative hyphema and postoperative hypotony were the complications encountered in both groups, whereas serous choroidal detachment and wound leakage were seen only in group 2. CONCLUSIONS: Intraoperative MMC applied at a concentration of 0.2 mg/ml controlled postoperative IOP as effectively as a 0.4-mg/ml concentration in high-risk cases of congenital glaucoma, but with a lower incidence of complications and thin-walled blebs.  相似文献   
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A study was made into the functional status of hypophysis, adrenal cortex, ovaries, and thyroid gland in patients with kraurosis and leukoplakia vulvae. The above patients demonstrated profound disturbances in the system hypophysis-ovaries, that attest to the need for applying corrective therapies to treat the disturbed hormonal homeostasis.  相似文献   
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METHODS: In a randomized double-blind study, 134 patients were given 500 mg metronidazole as an intravenous infusion immediately before operation for abdominal total hysterectomy and again 8 hours later and 124 patients received placebo. RESULTS: There was more wound infection, postoperative hospitalization was longer and the sedimentation rate on the sixth postoperative day was significantly higher in the placebo group. There was no difference in postoperative temperature. Postoperative wound infections occurred in 12% in the placebo group and 6% in the metronidazole group. Eight percent in the total material had urinary tract infections, the diagnosis was based on urine cultures. CONCLUSIONS: Prophylaxis with intravenous infusion of metronidazole is recommended in total hysterectomies.  相似文献   
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Evidence from several central nervous system (CNS) inflammatory disease models suggests that intrathecal complement synthesis may contribute to early inflammatory events in the brain. In this study, we examined the expression of the receptor for C5a (C5aR), a potent inflammatory and chemotactic factor, in the brains of transgenic mice with constitutive astrocyte expression of interleukin-3 (IL-3), a hematopoietic and immunomodulatory cytokine. By in situ hybridization, we demonstrated that cells infiltrating the cerebellar meninges, the cerebellum, and demyelinating lesions in the cerebellum were strongly positive for C5aR mRNA. By immunohistochemistry, the infiltrating cells expressing the C5aR were identified as macrophages based on staining with antibodies to the complement receptor type 3 and F4/80, a mouse macrophage-specific marker. In addition, some of the cells in cerebellar lesions were positive for the astrocyte-specific marker, glial fibrillary acidic protein, suggesting that a subpopulation of astrocytes in these lesions express elevated levels of the C5aR. Increased C5aR expression was also observed in cortical neurons in the occipital cortex and in pyramidal neurons in the cornu ammonis and subiculum of the hippocampus, at both the protein and mRNA levels. These data suggest that IL-3 may play an immunomodulatory role in C5aR expression on several cell types in the brain and that increased C5aR expression correlates with the pathology seen in this model. The transgenic mice used in this study provide a useful tool for characterizing the mechanism of regulation of the C5aR expression and for examining the functions of this chemotactic receptor in CNS inflammation.  相似文献   
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PURPOSE: Previous studies of monochromatic visual evoked potentials confirm the strong suppression of (the cortical representation of) paracentral retinal areas of functionally amblyopic eyes, by a flat response to a blue stimulus. A clinical trial stimulating these areas with blue light was encouraging, and justified a prospective comparison of this treatment with conventional classic treatment. SUBJECTS AND METHODS: In 50 strabismic children with amblyopia, the blue filter treatment protocol (flash stimulation with, and the wearing of, a blue filter during occlusion of the better eye for one hour daily) was compared with the classical treatment (full time total occlusion by patch) in a prospective matched and randomized study. Patients 3 to 7 years old without previous treatment and a visual acuity up to 0.3 were admitted to the study. Visual acuity and fixation behavior were used as the parameters of comparison. Visual Evoked Potentials by monochromatic flashes were also studied. Results of treatment were compared after 6 months. RESULTS: The visual acuity outcome for the blue filter treatment was "statistically significantly" better (p=0.005). The greatest improvement was seen in the subgroup of children with eccentric fixation (p=0.01). Fixation behavior also showed a better outcome from the blue filter treatment (p=0.05) favoring especially children between 3 and 5 years. In children of this age with a visual acuity better than 0.1 we found a very "statistically significant" difference between the two treatments (p=0.004). In children 3 to 5 years old with poorer visual acuity we also found a "statistically significant" difference in the two treatments (p=0.04). The interocular difference of amplitude on the Visual Evoked Potentials also demonstrated more improvement in children treated with the blue filter. This treatment improved especially the cortical response to blue flash stimulation, correlating to paracentral retinal areas. CONCLUSIONS: The blue filter treatment protocol provided better results for treating amblyopia than the conventional classic occlusion treatment method. We propose that stimulation of these paracentral retinal areas triggers a better disinhibition of a functionally amblyopic eye.  相似文献   
39.
The modulatory effects of 1DMe (d-Tyr-Leu-(NMe)Phe-Gln-Pro-Gln-Arg-Phe-NH2), an agonist of Neuropeptide FF (NPFF) receptors, on opioid antinociceptive activity have been compared in naive and tolerant mice in the tail-flick and the hot-plate tests. In naive mice, 1DMe alone had no effect on pain threshold but decreased dose-dependently (3-22 nmol) the analgesic activity of morphine in both tests. In tolerant mice, injections of 60-fold lower doses of 1DMe (0.05-0.5 nmol) reverse morphine-induced analgesia in the tail-flick test but this anti-opioid effect was no longer observed with the highest doses of 1DMe tested (3-22 nmol). In the hot-plate test, the anti-opioid action of 1DMe was not detected, whatever doses tested. Neither the NPFF-like immunoreactivity content of spinal cord and of olfactory bulbs, nor the density of NPFF receptors in olfactory bulbs, were altered. These results indicate that a chronic morphine treatment modifies the pharmacological properties of NPFF but the type of pain test is crucial in determining NPFF effects.  相似文献   
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PURPOSE: Despite its common use as an indicator of apoptosis, little is known about the mechanisms controlling apoptotic DNA fragmentation in irradiated cells. This review discusses the pathways of chromatin fragmentation, and the role of both nucleases and chromatin structure in this process. DEFINITIONS: DNA fragmentation linked to apoptosis is a combination of cleavage events excising both large DNA fragments within the range 0.4-1.0 Mbp and 50 kbp followed by random cuts within internucleosomal regions (i.e. DNA laddering). The first two cleavage steps can be detected in virtually all apoptotic cells, but DNA laddering is not ubiquitously observed. Endonucleases that mediate this cleavage of chromatin may be classified by substrate specificity, mode of DNA cleavage and their cofactor requirements. CONCLUSIONS: Three major pathways of DNA fragmentation are proposed and discussed: (1) upregulation of endonucleases, (2) their intranuclear/intracellular redistribution and (3) primary changes of chromatin structure.  相似文献   
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