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91.
目的了解工艺改进后金属酸洗岗位职业危害因素及浓度降低效果,控制岗位人员职业危害因素接受量,预防职业病的发生。方法通过对某钢铁厂金属酸洗车间工艺改进前后酸洗和天车操作两个岗位职业危害因素监测结果进行对比、分析,确定工艺改进对控制岗位职业危害的效果。结果天车操作室:硫酸雾合格率由60.2%上升到88.9%,盐酸雾合格率由63.0%提高到100%;酸洗操作岗位:硫酸雾合格率由37.0%上升到87.9%,盐酸雾合格率由49.0%提高到99.1%。经统计学分析,工艺改进前与工艺改进后硫酸雾、盐酸雾总体合格率差异均有显著性(P〈0.05),说明工艺改进后主要岗位职业危害因素减低的合格率均有较大提升。结论工艺改进对控制酸洗岗位职业危害效果明显。 相似文献
92.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献
93.
A Comparative Study on the Effect of BCG-PSN and Thymopeptides on T-lymphocyte Subsets of Normal and Immunosuppressed Mice 总被引:2,自引:0,他引:2
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c… 相似文献
94.
冠心病患者血清同型半胱氨酸与叶酸、维生素B12水平的变化 总被引:6,自引:0,他引:6
目的 探讨冠心病患者血清同型半胱氨酸(HCY)与叶酸、维生素B12浓度的变化及其相关性。方法 选择84例经冠状动脉造影术证实为冠心病的患者,应用荧光偏振免疫分析法(FPIA)测定血清HCY浓度,离子捕获免疫分析法(ICIA)测定血清叶酸浓度,非均相微粒子酶免疫分析法(MEIA)测定血清维生素B12浓度。结果 冠心病患者血清HCY浓度增高,与正常对照组比较有显著性意义(P<0.001),而叶酸、维生素B12浓度则降低,与正常对照组比较有显著性意义(P<0.001),以上两种变化呈负相关(P<0.001)。结论 同型半胱氨酸血症是冠心病的新的独立危险因素,叶酸、维生素B12缺乏可能是诱发高HCY的重要因素。 相似文献
95.
青黛颗粒抗炎、镇痛作用的实验研究 总被引:3,自引:0,他引:3
目的 :通过对青黛颗粒抗炎、镇痛作用的实验研究 ,探讨该药治疗溃疡性结肠炎的作用机理。方法 :采用小鼠醋酸扭体法、大鼠棉球肉芽肿法和角叉菜胶所致大鼠足肿胀方法。结果 :青黛颗粒给药高、中、低剂量组和阳性对照药组均明显降低小鼠扭体次数 (P<0 .0 5~P<0 .0 1)。对大鼠棉球肉芽肿和大鼠足肿胀有显著的抑制作用 (P <0 .0 1~P <0 .0 0 1)。结论 :青黛颗粒分别对大鼠具有抗炎、对小鼠具有镇痛作用。且镇痛作用呈量效关系 相似文献
96.
N. Ozaki D. Nakahara Y. Kasahara T. Nagatsu 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(3):175-179
Summary The suprachiasmatic nucleus (SCN) has been identified as a major circadian pacemaker. Methamphetamine has been shown to modify the behavior of circadian rhythms. We detected extracellular serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the SCN in freely moving rats, using a microdialysis method, to investigate biochemical effects of methamphetamine in the SCN. Methamphetamine infusion into the SCN dose-dependently increased extracellular 5-HT and decreased extracellular 5-HIAA. 相似文献
97.
Quisqualate lesions of rat NBM: Selective effects on working memory in a double Y-maze 总被引:8,自引:0,他引:8
S.L. Biggan R.J. Beninger J. Cockhill K. Jhamandas R.J.Boegman 《Brain research bulletin》1991,26(4):613-616
Some authors have reported that quisqualic acid lesions of the nucleus basalis magnocellularis (NBM), although producing large cortical cholinergic losses, have little effect on memory. The purpose of the present study was to investigate the effects of quisqualic acid lesions of the NBM on working and reference memory in a double Y-maze. Each trial started with placement into one of the two end arms of the first Y-maze, and the correct response was to go down the stem (reference memory). Access was then given to the second Y-maze, the correct response being conditional upon the side of the first Y-maze from which that trial had begun (working memory). Rats were trained to an 88% correct criterion and were then given either bilateral quisqualic acid (60 nM, 0.5 microliters) or sham lesions (0.9% saline, 0.5 microliters) of the NBM. One week postsurgery, rats were tested on the double Y-maze task with delays of 0, 5 or 30 seconds being introduced prior to both the working and reference memory choice. NBM lesions produced a 63.2 +/- 6.2% decrease of cortical choline acetyltransferase (ChAT) compared to unoperated controls. Delays affected only the working memory of the sham group. Rats with lesions showed a significant impairment of working memory at all delays, but no change in reference memory. Results indicate that quisqualic acid lesions of the NBM that produce significant reductions in cortical ChAT selectively impair working memory. 相似文献
98.
MOTOYOSHI NOMIZU YOSHIMASA INAGAKI TAKEYOSHI YAMASHITA AKO OHKUBO AKIRA OTAKA NOBUTAKA FUJII PETER P. ROLLER HARUAKI YAJIMA 《Chemical biology & drug design》1991,37(2):145-152
A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nin-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin. 相似文献
99.
A Hatziefthimiou A Mitsacos E Mitsaki A Plaitakis E D Kouvelas 《Journal of neuroscience research》1991,28(3):367-375
In the present work the distribution of L-glutamate binding sites in the different layers of human cerebellum of normal individuals and of seven patients who died with olivopontocerebellar atrophy (OPCA) was examined with the technique of quantitative autoradiography. Specific L-[3H]glutamate binding was higher in the molecular than in the granule cell layer of normal cerebellar tissue. A significant decrease of L-[3H]glutamate specific binding was observed in the molecular layer of all OPCA tissues. In the granule cell layer L-[3H]glutamate binding was decreased only in two patients who suffered from late-onset sporadic OPCA and in one patient who suffered from a form of OPCA inherited in a dominant manner. Quisqualate-sensitive binding sites were the most abundant binding sites in the molecular layer of normal cerebella, whereas N-methyl-D-aspartic acid (NMDA)-sensitive binding sites were the most abundant type in the granule cell layer. A significant decrease of quisqualate-sensitive and an increase in NMDA-sensitive binding sites were observed in the molecular layer of OPCA cerebellar tissues. No significant changes were observed in the granule cell layer of these tissues. 相似文献
100.
YY Ho 《Journal of Medical Imaging and Radiation Oncology》2005,49(6):445-459
Bone and soft tissue tumours are rare neoplasms. There are five major roles of imaging in the management of primary musculoskeletal tumours, that is, to differentiate between benignity and malignancy, to evaluate for local tumour extension, to screen for metastases, to judge the effect of chemotherapy, and to monitor for recurrence. To accomplish this, multiple modalities are required because no single examination is able to complete all these tasks. These modalities include plain radiography, CT, MRI, conventional nuclear medicine as well as positron emission tomography (PET) imaging. Elsewhere, PET imaging has been discussed at length, because it is likely to be superior in the assessment of bone and soft tissue tumours over conventional nuclear medicine procedures. However, conventional nuclear medicine may be of value when PET is unavailable. In this review, an overview of anatomical imaging will be given and the role of non‐PET functional imaging will be discussed in detail. A variety of illustrative cases will be presented. 相似文献