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51.
目的 了解青藏线水源水质卫生状况,为施工部队水源选择、洁治消毒提供参考依据。方法 硬度使用EDTA-2Na进行滴定,其余指标使用88型检水检毒箱测定。结果施工沿线基本无现成可利用的水源,所调查22个水源中9个存在生物污染,3个水源氯化物或硫酸盐严重超标;5个水源总铁严重超标。结论 摸清了放工沿线水源水质卫生状况,为部队施工和以后执行任 务时选择水源、进行水质改善提供了科学依据。 相似文献
52.
Mervi Pitkänen Jouni Sirviö Ewen MacDonald Suvi Niemi Tommi Ekonsalo Paavo Riekkinen Sr. 《European neuropsychopharmacology》1995,5(4):457-463
The present study was undertaken to investigate the effects of modulation of the (NMDA) receptor on learning and memory. Thus, the performance of rats treated with d-cycloserine, a partial agonist at the glycine recognition site of the NMDA receptor complex, and MK-801, a noncompetitive NMDA receptor antagonist, either alone or concurrently were assessed in radial arm maze and water maze tasks. Administration of MK-801 (0.1 mg/kg, i.p.) impaired acquisition in the water maze (increased escape latency and distance) and working memory in the radial arm maze (increased re-entries) in rats. Moreover, in the radial arm maze, MK-801 disrupted locomotion (increased latencies and decreased arm entries per minute) and impaired the acquisition of reference memory (increased number of errors) performance of rats. d-Cycloserine (0.03, 0.3, 1.0, 3.0, 10 mg/kg, i.p.) had no effects on acquisition or memory performance of control or MK-801-treated rats in either of these tasks. However, d-cycloserine (0.03, 0.3, 3.0 mg/kg) reversed the MK-801-induced disruption in locomotion. Furthermore, 3.0 mg/kg d-cycloserine increased behavioral activity and also decreased the time needed to complete the task in control animals. To conclude, our results suggest that the consequences of NMDA receptor modulation on learning and memory processes and sensorimotor functions may be functionally different or have distinct anatomical locations. 相似文献
53.
Characteristics of bone mineral density and soft tissue composition of obese Japanese women: Application of dual-energy X-ray absorptiometry 总被引:2,自引:0,他引:2
We studied the characteristics of bone mineral density (BMD) and soft tissue composition in obese Japanese women using dual-energy
X-ray absorptiometry. Eighty-nine women, aged 45–85 years, were divided into three groups according to their body mass index
(BMI): a thin group (n = 38; BMI < 21), a standard weight group (n = 31; BMI, 21–25), and an obese group (n = 20; BMI ≥ 25). The mean BMD of the second to fourth lumbar vertebrae and BMD of the lumbar spine, thoracic spine, pelvis,
legs, and ribs of the thin group were significantly lower than those of the standard weight group or the obese group (P < 0.05), whereas no significant difference in total body BMD was observed among the three groups. There was a significant
difference in total and regional fat mass among the three groups (P < 0.05). Lean mass of legs and total lean mass showed a significant difference between the thin group and the obese group
(P < 0.05). The results showed that obesity was associated with higher BMD of weight bearing-bones and ribs, high total and
regional fat mass, and high lean mass of bilateral legs and total lean mass. We suggest that obesity may contribute to the
prevention of bone loss of weight-bearing bones and ribs and muscular atrophy of the legs.
Received: Sept. 30, 1998 / Accepted: Dec. 10, 1998 相似文献
54.
Evaluation of esophageal bile reflux after total gastrectomy by gastrointestinal and hepatobiliary dual scintigraphy 总被引:2,自引:0,他引:2
Conducting the qualitative evaluation of reconstruction methods is difficult because of their complexity. The aim of the present
study was to compare esophageal bile and food reflux by performing gastrointestinal and hepatobiliary dual scintigraphy (GHDS)
after various methods of reconstruction following total gastrectomy. Of 17 patients studied, 4 had undergone Roux-en-Y anastomoses
(R-Y); 6, jejunal pouch-Y anastomoses (P-Y); and 7, jejunal pouch interposition (P-I). GHDS was performed 1 year after surgery
using111In-diethylene triamine pentaacetic acid administered orally, and99mTc-pyridoxyl-5-methyl tryptophan administered intravenously. Imaging data from a gamma camera were stored in and processed
by a data analyzer. Three patients who had undergone R-Y and one who had undergone P-I complained of heartburn, while one
who had undergone R-Y, two who had undergone P-Y, and three who had undergone P-I complained of a feeling of fullness. Esophageal
bile reflux was confirmed by GHDS in four of the patients who had undergone R-Y, one who had undergone P-Y, and four who had
undergone P-I. Moreover, GHDS demonstrated food retention in two patients who had undergone R-Y, five who had undergone P-Y,
and four who had undergone P-I. Weight loss was closely related to the esophageal reflux of bile or food which can be accurately
detected by GHDS. Despite the absence of heartburn, patients diagnosed as having bile reflux by GHDS showed poor recovery
of body weight. 相似文献
55.
Dr. Rolando Grave de Peralta Menendez Sara L. Gonzalez Andino Bernd Lütkenhöner 《Brain topography》1996,9(2):117-124
Summary This paper introduces the concept of the resolution matrix as the basis for an objective theoretical comparison of distributed linear inverse solutions to the neuroelectromagnetic inverse problem. In particular, we describe how figures of merit derived from the resolution matrices can be represented graphically to evaluate merits and shortcomings of the different solutions. The use of the figures of merit is illustrated with two solutions that consider minimal a priori information about the generators: Classical Minimum Norm and Backus Gilbert. We recommend to start any analysis with the individual exploration of the resolution kernel for each grid point or at least for those points where the activity is likely to occur. This analysis might help in selecting the optimal inverse for the sources that are supposed to be active in the process under study.This work was supported by a grant from the Deutsche Forschungsgemeinschaft (Klinische Forschergruppe Biomagnetismus and Biosignalanalyse). Partial support was received from Swiss National Foundation grant 4038-044081/1. 相似文献
56.
Michael Scherg 《Brain topography》1992,5(2):103-111
Functional imaging of electric brain activity requires specific models to transform the signals recorded at the surface of the human head into an image. Two categories of model are available: single-time-point and spatio-temporal methods. The instantaneous methods rely only on the few voltage differences measured at one sampling point. To create a spatial image from this limited information, they require strict assumptions that rarely conform with the underlying physiology. Spatio-temporal models create two kinds of images: first, a spatial image of discrete equivalent multiple dipoles or regional sources, and second, an image of source current waveforms that reflect the temporal dynamics of the brain activity in circumscribed areas. The accuracy of the spatial image is model dependent and limited, but it can be validated from the spatio-temporal data by the "regional source imaging" technique, introduced here. The source waveforms are linear combinations of the scalp waveforms, and thus, specific derivations which image local brain activities at a macroscopic level. Brain source imaging of somatosensory evoked potentials revealed temporally overlapping activities from the brainstem, thalamus and from multiple sources in the region of the contralateral somatosensory projection areas. 相似文献
57.
58.
玉米粉水解物作为红霉素发酵培养基的研究 总被引:2,自引:0,他引:2
研究了摇瓶试验中玉米粉水解物替代葡萄糖发酵红霉素的最佳培养基组成。用均匀设计法得到发酵基础培养基的最佳配比(wB,%):玉米粉3.6,黄豆饼粉2.0,玉米浆0.23,碳酸钙0.5,淀粉0.6;用正交试验得到了优化的补混合料配比(%):玉米粉4.5,黄豆饼粉2.0,硫酸铵1.0,酵母粉2.0;并得到了玉米粉的最适水解条件。30t发酵罐放大实验结果表明,用玉米粉水解物替代葡萄糖作碳源发酵红霉素,发酵单位提高5.8%,综合生产成本降低26.0%。 相似文献
59.
Chapenko S Folkmane I Tomsone V Amerika D Rozentals R Murovska M 《Clinical transplantation》2000,14(5):486-492
The ubiquity of human cytomegalovirus (CMV) and human herpesvirus-7 (HHV-7), as well as activation of these viruses during immunosuppression, allows the suggestion that both viruses could participate in the development of 'CMV disease' in patients after renal transplantation (RT). The aim of our research was to study the prevalence of latent CMV and HHV-7 infections in patients before RT, to determine interaction between these viruses in dual infection and possible association of their reactivation with the progression of 'CMV disease' after RT. Peripheral blood samples were collected from 49 patients before and up to 10-12 wk after RT. The methods used for diagnostics of viral infections were: serology, nested polymerase chain reaction (nPCR) analysis of peripheral blood leukocytes (PBL) and plasma, and virus isolation in cell cultures (morphological changes, nPCR analysis of cellular and cell-free samples, indirect immunofluorescence analysis). Before RT, CMV and HHV-7 DNAs were detected in PBL but not in the plasma samples, which indicates the presence of latent viral infection in patients. Latent dual (CMV + HHV-7) infection was prevalent (51.0%) in 49 patients, while CMV and HHV-7 infections alone were detected in 26.5 and 12.2% of patients, respectively. Risk of viral disease after RT, for recipients with latent dual infection before RT, was 12- and 2.2-fold higher in comparison with CMV and HHV-7 infections alone, respectively. Frequency of dual infection in 18 recipients with 'viral syndrome' or 'CMV disease' after RT was reliably higher (13/18, 81.3%) than CMV (1/18, 6.2%) (p < 0.025) and HHV-7 (2/18, 12.5%) (p < 0.025) infections alone. HHV-7 reactivation preceded CMV reactivation in 77.0% of the cases of dual infection in the recipients with viral disease and reactivation of both viruses preceded the development of viral disease. Severe 'CMV disease' developed in 2 out of 2 recipients with CMV primary infection and 'viral syndrome' in 1 recipient with CMV reinfection. The reactivation of CMV was detected in all recipients prior to onset of the disease. Correlation was shown between reactivation of latent HHV-7 infection and development of febrile syndrome in 2 out of 2 recipients with HHV-7 infection alone. Taking into account that dual infection is an increased risk factor for 'viral syndrome' and 'CMV disease' development, screening diagnostic should include testing for both viral infections in transplant donors as well as in recipients before and after RT. 相似文献
60.