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991.
The nervous system of two larval stages (cercariae, metacercariae) of eye flukeDiplostomum spathaceum was investigated immunocytochemically by the application of antisera to the amino acid glutamate and to neuropeptides isolated from invertebrates (Mollusca) and from vertebrates to whole-mount preparations. In cercariae, positive immunoreactivity (IR) was observed with antisera raised against Catch-relaxing peptide (CARP), FMRFamide, -caudodorsal cell peptide (-CDCP), substance P, vasotocin, and vasopressin. In metacercariae, in addition to positive staining with these antisera, the ones raised against glutamate, APGWamide, caudodorsal cell hormone I (CDCH-I), and small cardiac peptide B (SCPB) also gave positive IR in the nervous system. In the two larval stages the most extensive pattern of IR was observed with anti-FMRFamide and anti-CARP. In the nervous system of metacercariae the same immunoreactive neurosubstances appeared to be present as in that of cercariae. The increase in the variety of immunoreactive neurosubstances in the more complex nervous system of metacercariae is discussed in relation to parasite development and to host adaptation. 相似文献
992.
Benno L. Petrig Terri L. Young Juan E. Grunwald Graham E. Quinn Charles E. Riva 《Lasers in medical science》1995,10(4):267-272
The present study was conducted to assess the feasibility of laser Doppler velocimetry in young infants, as a prelude to ultimately undertaking such measurements in premature infants. A portable, unidirectional laser Doppler velocimeter was developed based on a Kowa RC-2 hand-held fundus camera. Six infants between 1 and 21 weeks of age were studied. Relative red blood cell velocity (fmax) at the centre of retinal arteries was measured over approximately 10 heart cycles. A pulsatility parameter (P=1–fmax.dia/fmax.sys), a summary index of vascular status, was determined from the average diastolic and systolic values of fmax. Velocity waveforms were obtained in four of the six infants. Arterial pulsatility for the group was 0.63±0.13. Precise non-invasive measurement of arterial red blood cell velocity waveforms in young infants was achieved. The high signal-to-noise ratio and temporal resolution of this data suggest that relative measurements of retinal blood flow may permit assessment of haemodynamic changes in premature infants. 相似文献
993.
Juan J. Tarin Josep LL. Romero Fernando Bonilla-Musoles 《Journal of assisted reproduction and genetics》1994,11(9):463-469
Purpose
To characterize and predict cycles generating slowcleaving embryos in in vitro fertilization, 86 cycles were retrospectively divided into two groups (slow, n=41, and fast, n=45 according to whether the number of blastomeres per embryo on day 3 was or > than the mean of the distribution, respectively.Results
Cycles generating slowcleaving embryos were treated with luteinizing hormonereleasing hormone agonist before ovarian stimulation for a shorter period (12.1±0.5 versus 15.6±1.1 days; P0.01) and had higher immaturity grade of oocyte-corona-cumulus complexes which resulted in embryos (1.6±0.1 vs 1.3±0.1; P0.05) when compared to cycles producing fastcleaving embryos. Both variables entered in a logistic regression model applied in order to predict the probability of a cycle generating slowcleaving embryos (goodness-of-fit chisquare=180.0, degrees of freedom (df)=80, P=0.4786. This model predicted correctly 86.7% (13 of 15) of cycles generating slowcleaving embryos and 83.3% (10 of 12) of cycles producing fastcleaving embryos when the estimated probability of a cycle producing slowcleaving embryos was 0.7 or 0.3, respectively.Conclusion
Shorter treatment with hormone-releasing hormone agonist before ovarian stimulation and higher immaturity grade of oocyte-corona-cumulus complexes which result in embryos are predictive characteristics of in vitro fertilization cycles generating slow-cleaving embryos. 相似文献
994.
目的 调查中国人民解放军总医院研究生对临床流行病学课程的认知和学习习惯情况,评价其学习效果并分析其可能的影响因素,为改进教学方式、提高学习效果提供相关数据。方法 采用横断面研究设计方法,以中国人民解放军总医院2020级全体研究生为研究对象,采用自填问卷方式收集调查资料。分析不同类别研究生对课程认知情况、学习习惯的差异,探讨影响学习效果的相关因素。连续变量组间差异比较采用t检验或Mann-WhitneyU检验,分类变量组间差异比较采用卡方检验或McNemar检验。结果 共纳入652名研究生进行分析,硕士研究生409人(62.7%),博士研究生243人(37.3%)。博士研究生听说过临床流行病学(χ2=19.99,P<0.001)、之前学过临床流行病学(χ2=9.20,P=0.002)、对本课程感兴趣(χ2=11.41,P=0.001)、认为本课程重要(χ2=10.71,P=0.001)、课前预习(χ2=11.21,P=0.001)、课后复习(χ2=3.29,P=0.001)及课堂积极讨论(χ2=11.64,P=0.001)的比例高于硕士研究生,差异有统计学意义。授课前全体研究生测验题总分平均为(5.50±1.62),授课后总分平均为(7.47±1.90),差异有统计学意义(t=-23.49,P<0.001)。统招研究生授课后成绩提高程度高于在职研究生,硕士群体中差异有统计学意义(t=4.41,P<0.001),博士群体中差异无统计学意义(t=0.94,P=0.351)。结论 不同类别研究生对临床流行病学知识点掌握程度在授课后均得到提升。但仍需针对不同类别研究生学习基础及短板的差异,改进相应的教学模式及过程,包括采用不同的教学方式和规范学习习惯等,从而提升研究生的课程学习效果。 相似文献
995.
静态负荷所致肌肉组织中自由基及酶变化的研究 总被引:2,自引:1,他引:1
目的观察静态负荷所致肌肉损伤后自由基和酶的变化。方法采用顺磁共振仪(ESR)技术测定半离体肌肉静态负荷后的自由基变化,同时测定了肌酸磷酸激酶(CPK)和乳酸脱氢酶(LDH)的变化。结果随着负荷的增大和实验时间的延长,自由基含量也随之增高,肌肉中CPK和LDH的活力均下降。结论静态负荷可以导致肌肉中自由基生成增加和酶外释。 相似文献
996.
蔬菜中甲胺磷残留量调查分析 总被引:1,自引:0,他引:1
目的了解蔬菜中甲胺磷残留量。方法调查奉化两个蔬菜市场。对5个品种20份蔬菜中甲胺磷残留量按“GB14876-94食品中甲胺磷残留量气相色谱测定法”测定。结果95%样品检出甲胺磷残留量,范围0.11~8.41mg/kg。结论蔬菜中甲胺磷污染十分严重,特别在带豆、青菜和萝卜菜。 相似文献
997.
998.
葡萄糖调节蛋白94在人胚胎发育中的表达 总被引:2,自引:0,他引:2
目的 为探讨葡萄糖调节蛋白94(GRP94)在胚胎发育中的作用,研究了10-31周人胎组织GRP94的定位及表达。方法 用SP免疫组织化学方法。结果 结肠粘膜上皮,肾小管上皮及肝细胞的胞质内,在10周已有GRP94的表达,18-20周时表达增多,一直维持较高水平。胃粘膜上皮及心肌细胞也有较强的表达。 相似文献
999.
Reques FG Rodriguez JL 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1999,11(6):385-394
The so called leukotriene antagonists or, more accurately, the leukotriene modifiers are a rather heterogeneous set of drugs that work by several mechanisms. Such mechanisms include: (i) 5-lipoxygenase enzyme inhibition (e.g. zileuton); (ii) 5-lipoxygenase-activating-protein inhibition (e.g. quiflapon, BAYx 1005); (iii) LTD4-receptor antagonism (e.g. zafirlukast, montelukast, MK-571, pranlukast). The first leukotriene modifiers tested (L-649,923 and tomelukast) had adverse gastrointestinal effects. Since then, several leukotriene modifiers have been marketed, including zafirlukast, zileuton and montelukast. Zafirlukast has been associated with 8 cases of Churg-Strauss syndrome, although these were probably not caused by zafirlukast. It is more likely that this syndrome is related to the underlying illness, which was masked by corticosteroids, and revealed after zafirlukast-mediated asthma treatment allowed steroid withdrawal and unmasking of underlying vasculitis. The main adverse effects of zileuton include liver function test abnormalities, while montelukast, the most recently marketed, has so far shown minimal adverse effects. Zafirlukast causes a decrease in warfarin clearance and a clinically significant increase in prothrombin time, probably by cytochrome P450 isoenzyme interactions. Moreover, terfenadine decreases zafirlukast maximum serum concentrations. Calcium antagonists, cyclosporin, cisapride and astemizole are metabolised via the cytochrome P450 system, and interactions with leukotriene modifiers can be expected. 相似文献
1000.
Juan SP 《The Journal of the Philippine Dental Association》1999,51(1):29-36
There is a compelling need to apply preventive programs in both private and community practice of dentistry. This is to maintain improvements in oral health in developed and industrialized countries, and to stem increases in oral diseases in underserved and developing ones. At the outset, the terms prevention and control must be understood. The former is considered to mean a procedure or course of action that prevents the onset of disease, whereas the latter, implies reversing or stabilizing disease conditions. To be more precise, prevention will refer to the pre-pathologic or pre-clinical stage encompassing the promotive and specific protection levels--primary prevention stage. On the other hand, control will encompass early diagnosis and prompt treatment, disability limitation and rehabilitation levels-termed also collectively, as pathologic, clinical and final stages, or secondary and tertiary prevention. Community-based programs are usually structured to compliment therapeutic interventions of oral diseases, as well as prevention. In this era, and towards the next millennium, preventive and control programs are given high priorities in order to minimize the need for curative, restorative and therapeutic management of oral diseases. This review of the literature will give emphasis on established methods and programs for the prevention and control of the two most common oral diseases, dental caries and periodontal disease. The problems, background, and oral health objectives for the year 2000 as proposed by the World Health Organization (WHO) and the Federation Dentaire Internationale (FDI), as well as the recent advances in oral health relative to these diseases will be discussed. Finally, to better improve the efficacy of existing prevention and control methods, research needs and areas of concern relative to these diseases will be given consideration. 相似文献