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891.
892.
BACKGROUND: Improved prognosis can be achieved in selected patients with peritoneal carcinomatosis (PC) by major surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). METHOD: Sixty seven patients with PC were operated with the aim of complete macroscopical cytoreduction followed by HIPEC (using cisplatin, mitomycin or mitoxantrone). Quality of life was assessed with the EORTC QLQ-C30 questionnaire. RESULTS: The patients had a variety of primary tumours, including appendix carcinomas (22/67). Mean operating time was 7 hours and complete cytoreduction was achieved in 58% of the patients. Overall morbidity was 34%. Post-operative mortality was 4.5%. The mean score for global health status of long-term survivors (20 questionnaires/25 patients) was 62.6 (73.3 for the control population, p=0.07). Functional status, particularly the role (56.4) and the social functioning (53.9) were impaired. CONCLUSION: Cytoreductive surgery combined with HIPEC is associated with an increased morbidity and mortality. Complications are predominantly related to major surgery. Following this aggressive treatment, survivors may achieve a satisfactory quality of life.  相似文献   
893.
Histological tissue sections of human testicular embryonal carcinoma from 13 patients and of a xenograft tumour in nude mice, as well as cell lines of human embryonal carcinoma, were investigated with eight different lectins to characterize the distribution of glycoconjugates in embryonal carcinoma. In all cases the malignant cells showed binding with Con A, WGA and RCA I conjugates, whereas other lectins were bound to some, but never to all, tumour cells in each group, revealing the heterogeneity of the malignant cells. A polarization of cancer cells was shown particularly with WGA and RCA I labelling, which was most intense on the luminal borders of the carcinoma cells, where pseudotubular structures were formed. The sugar staining properties were retained in cell culture and in the xenograft tumour. Regardless of the germ cell origin, embryonal carcinoma cells differed from normal germ cells. The distribution of glycoconjugates was also different from that of testicular carcinoma-in-situ germ cells, which share morphological features and the pattern of glycosylation with seminoma cells. However, the similarities in lectin binding pattern of seminomas and embryonal carcinomas suggest the close relationship between the two types of testicular malignancy, without excluding the possibility that embryonal carcinomas were derived from seminomas. Although lectins seem to be less important for differential diagnostic use in testicular cancer, our findings showed the usefulness of lectin histochemistry for characterization of embryonal carcinoma.  相似文献   
894.
895.
Using conventional two electrode voltage clamp techniques we have studied the effects of Pb2+, triethyl lead (TEL) and Hg2+ on voltage-activated calcium channels of Aplysia neurons and found that all three metals are potent inhibitors at micromolar concentrations. However, the time course of current reduction or block and its reversibility vary when comparing Pb2+ to TEL and Hg2+. With application of Pb2+ the calcium current decreases immediately and a steady state is reached within three to seven minutes, depending upon the concentration of Pb2+ (IC50 = 61 microM). The block was easily reversed upon wash out of Pb2+ with a time course similar to that of onset. Perfusion with either TEL (5 to 50 microM) or Hg2+ (5 to 200 microM) resulted only in a small reduction of current when the substances reached the cell membrane but with clear reduction within 2 min. The decrease continued at about the same speed for the total duration of the application. Upon washing there was no recovery of the response. At the onset of washing the rate of current decline stopped for several minutes, but then the current continued to decline at a slower rate in the absence of toxicant. Our data suggest that Pb2+ acts by a direct and reversible blockade of the calcium channel. In contrast TEL and Hg2+ act slowly and irreversibly to block calcium channels at concentrations which do not greatly affect membrane potential or resistance. In spite of the slow time course these substances are probably acting directly on the calcium channel.  相似文献   
896.
This paper describes the implementation of an ultraviolet (UV) laser (Spectra Physics 171-18 with 3 lines: 334, 351 and 364 nm in UV) as light source for fluorescence confocal scanning microscopy. With this instrument it is possible to use fluorophores not previously available for confocal laser microscopical imaging of fluorophores such as fluoro-gold and AMCA. In the study we show confocal laser microscopical imaging of fluorescent motoneurons labelled by retrograde transport of fluoro-gold and AMCA-fluorescent axon terminals labelled with antisera against immunogenes as thyrotropin-releasing hormone (TRH) and calcitonin gene-related peptide (CGRP). These two fluorophores may be recorded simultaneously or separately by using a filter that suppresses the emission of one of the fluorophores. The described instrument should also be useful in applications involving detection of monoamines by the Falck-Hillarp technique, as well as measurements of cytosolic free calcium by indicators such as Fura-2 and Indo-1. Measurements performed in reflected and fluorescence light indicated that the resolution along the optical axis improved by about 25% when UV (351 nm) is used instead of visible light (514 nm). This figure is close to that expected on theoretical basis. There are, however, also serious problems related to the use of UV excitation. Firstly, objectives must be selected based on their UV transmission properties. Secondly, chromatic aberration may cause a substantial focal shift between illuminating and emitted light, calling for a flexible instrumental design in order to allow for compensation. As shown here, this problem can be circumvented by using reflecting objectives but at a price of lower resolution compared with high-aperture refracting objectives.  相似文献   
897.
Application of Microencapsulation Technology to Improve theStability of Citral in Rodent Diets. KUHN., G. O., MCCAMPBELL,P., SLNGMASTER, G., ARNESON, D. W., AND JAMESON, C. W. (1991).Fundam. Appl. Toxicol. 17, 635–640. Citral is a widelyused flavoring and scenting agent which is employed in numerousfood, industrial, and household products. Although the currentregulatory status of citral lists it as a GRAS chemical on theFDA list, the chemical is a reactive beta-substituted vinylaldehyde that has been shown to induce irritations of skin andmucous membranes, and to exhibit a dose-dependent teratogeniceffect on embryos of white leghorn chickens. Because of thesefactors, citral was nominated by the National Toxicology Programfor carcinogenesis study. Stability studies of dose formulationsof citral (0.02%) in NIH-07 rodent diet indicated a loss of41% of the citral after 1 day in a rat cage, due mainly to volatilityand reactivity with diet components. The chemical was subsequentlymicroencapsulated using a shell medium of food-grade modifiedcornstarch and sucrose, and then formulated into NIH-07 diet(0.02%) for various stability studies. Results after 7 daysin a rat cage showed 95% retention of chemical; diet that hadbeen stored 21 days retained 95% at 5°C storage and 89%at room temperature. An assessment of the purity of the citralin the microcapsules indicated that total impurities increasedfrom 0.7% in the neat chemical to 1.1% in the encapsulated chemical.  相似文献   
898.
Summary The influence of mediolateral deformity, tibial torsion, and different centers of foot support was studied with a three-dimensional computer model that incorporates the significant muscles of the lower extremities needed for quasi-static walking. This theoretical method avoids the variability in gait pattern from the pain and discomfort associated with deformity in patients. The study illustrates the possible importance of the muscle force on the load across the knee and ankle. High strains in the medial gastrocnemius and the medial hamstring created particularly high loads in the medial compartment of the knee. Internal torsion and varus deformity were associated with the highest loads in the medial compartment of the knee, although the peak load for each deformity occurred in different phases of the gait cycle. Both external torsion and valgus deformity generally decreased the load in the medial compartment, but early in the gait cycle external torsion increased the loads on the medial side. In addition, when the center of support of the body was in the forefoot, the loads through the knee were lower than when foot support was at the heel. As expected, if the center of support was on the lateral foot line, the lateral compartment was subjected to more load and, conversely, when the center of support was on the medial part of the foot the medial compartment of the knee was more loaded. Although the predicted forces agree well with those found with other methods, we think that the model is best used to measure the direction of influence of specific factors.  相似文献   
899.
H O Svensson  G B Andersson 《Spine》1989,14(5):517-522
The association between low-back pain (LBP) and different work factors was investigated in a retrospective cross-sectional study of a random sample of 1,760 38- to 64-year-old women. The life-time incidence of LBP was 66% and the prevalence was 35%. In a univariate analysis, eight work variables correlated to LBP viz. more forward bending, more lifting, more standing, more monotonous work, dissatisfaction with the work tasks, dissatisfaction with the work environment, a higher degree of worry, and fatigue at the end of the work day. In a covariate analysis, however, only the three psychological variables remained directly associated to LBP viz. dissatisfaction with the work environment, a higher degree of worry, and fatigue at the end of the work day.  相似文献   
900.
Estimation of plasma cortisol by fluorometric technique desorbed by Mallingly's was carried out in 56 cases, including 38 cases of myopia (19 cases of simple myopia and 19 cases of degenerative myopia) and 18 normal individuals. Urinary 17-keto steroids/24 hours was also estimated by Zimmermann technique in 12 out of the 56 cases, which include 8 cases of myopia (4 cases of simple myopia and 4 cases of degenerative myopia) and 4 normal individuals as control. Plasma cortisol level is lower in simple and degenerative myopia than in normal subjects, but on statistical analysis the difference was not of much significance. Patients with simple myopia with positive family history showed lower value of plasma cortisol than patients with simple myopia with negative family history, the difference was also statistically insignificant (P-0.1). In degenerative myopia patients, with and without family history, there was very little difference in plasma cortisol level and statistically highly insignificant (P-0.8). Urinary 17 keto steroid/24 hour values are lower in simple and degenerative myopia than in normal subjects.  相似文献   
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