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141.
A Zober D Schilling MG Ott P Schauwecker JF Riemann P Messerer 《Canadian Metallurgical Quarterly》1998,40(7):586-594
Although gastrointestinal (GI) illnesses account for considerable sick absenteeism, there have been few workplace studies of GI disorders. We determined the prevalence of Helicobacter pylori infection by serology and assessed its relation to upper GI tract complaints, personal ulcer history, and family history of stomach cancer in 6,143 employees (mean age, 40.4 years) at BASF's main chemical production facilities in Ludwigshafen, Germany. Employees were recruited during occupational health clinic visits (n = 4,488) and through broad communications efforts (n = 1,655). Participation among clinic attendees was 66%, and this recruitment method was particularly effective in reaching shift employees. Positive immunoglobulin G (IgG) serology (38.2%), ulcers (4.9%), nonulcer dyspepsia (20.4%), and a family history of stomach cancer (6.1%) were common occurrences in this work setting. Further diagnostic evaluation and eradication therapy was recommended for 795 employees (12.9%), based on a combination of positive serology and either upper GI tract complaints or family stomach cancer history, and has been completed for 541 employees. A weak but consistent association was seen between positive serology and cigarette smoking, and shift work was found to be associated with positive serology, but not with ulcer or nonulcer dyspepsia occurrence. 相似文献
142.
大型SMTP服务器的设计与实现 总被引:1,自引:1,他引:1
给出了一种大型SMTP服务器系统的分布式结构、SMTP服务器扩展的方法以及MIME格式的电子邮件解析方式,同时给出了邮件的存储方式、邮件列表的结构和邮件列表的处理方式以及系统核心模块的实现代码。在系统实现中采用了面向对象技术和多线程技术,系统完全由标准C 语言实现。该SMTP系统适于大型电子邮件系统应用,它能够同时处理大量并发邮件操作,运行在各种操作系统与硬件平台上。 相似文献
143.
It is well known that variations in cardiac cycle length or heart rates may be used for noninvasive evaluation of autonomic cardiovascular control. The investigation uses an original procedure. The data for analysis of cardiac cycle length variations (CCLV) are those obtained regularly at follow-up intervals, random 24-hour Holter 2-lead ECG recordings for 5 sec, and simultaneously calculated continuous sequence of mean heart rate. With the procedure, the correlations of CCLV with the parameters reflecting the early postoperative status of patients with CHD, including acute myocardial infarction, acute heart failure, rhythm and conduction disturbances, as well as age, operative stress, concurrent diseases. The findings are of both diagnostic and predictive value at subsequent stages of CHD treatment. 相似文献
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145.
MG Marciani G Santone G Sancesario R Massa P Stanzione G Bernardi 《Canadian Metallurgical Quarterly》1993,8(2):115-120
Phenotypic and functional aspects of melanoma-hyaluronate interactions were investigated by studying the expression of CD44, cell migration, and transmembrane penetration of human melanoma cell lines on hyaluronate-coated substrates. Expression of CD44 was tested by flow cytometry on seven human melanoma cell lines. Strong reactivity with anti-CD44 monoclonal antibody was observed in four of seven of the cell lines. Migration studies of CD44(+) cell lines on hyaluronic acid- and chondroitin-6-sulfate-coated substrates, using time-lapse video-microscopy, showed a dramatic dose-dependent increase in migration rate on hyaluronate but not on chondroitin-6-sulfate. Moreover, CD44(-) cell lines showed no modification in migration rate on either substrate. Addition of soluble hyaluronate produced a dose-dependent inhibition of acceleration of CD44(+)cells on hyaluronate-coated substrates, whereas addition of chondroitin-6-sulfate had no effect. Migration inhibition experiments with soluble CD44 (CD44 receptor globulin) also showed specific blocking of the migration of CD44(+) cells on hyaluronate. Haptotactic invasion was increased in CD44(+) cell lines through hyaluronate-coated polycarbonate membranes, whereas no change was detected on chondroitin-6-sulfate-coated membranes. CD44(-) cell lines showed no response to either type of coating. In the melanoma cell lines tested, the expression of CD44 correlated with in vitro migration and invasiveness on hyaluronate substrates. Taken together, our data are consistent with the suggestion that CD44 may play a role in stimulating in vivo aggressiveness of tumors through hyaluronate-rich stroma. 相似文献
146.
SH Thomas JE Horner K Chew J Connolly B Dorani L Bevan S Bhattacharyya MG Bramble KH Han A Rodgers B Sen B Tesfayohannes H Wynne DN Bateman 《Canadian Metallurgical Quarterly》1997,16(9):495-500
1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately. 相似文献
147.
GA Murphy MS Moore G Drivas P Pérez de la Ossa A Villamarin P D'Eustachio MG Rush 《Canadian Metallurgical Quarterly》1997,8(12):2591-2604
Ran, the small, predominantly nuclear GTPase, has been implicated in the regulation of a variety of cellular processes including cell cycle progression, nuclear-cytoplasmic trafficking of RNA and protein, nuclear structure, and DNA synthesis. It is not known whether Ran functions directly in each process or whether many of its roles may be secondary to a direct role in only one, for example, nuclear protein import. To identify biochemical links between Ran and its functional target(s), we have generated and examined the properties of a putative Ran effector mutation, T42A-Ran. T42A-Ran binds guanine nucleotides as well as wild-type Ran and responds as well as wild-type Ran to GTP or GDP exchange stimulated by the Ran-specific guanine nucleotide exchange factor, RCC1. T42A-Ran.GDP also retains the ability to bind p10/NTF2, a component of the nuclear import pathway. In contrast to wild-type Ran, T42A-Ran.GTP binds very weakly or not detectably to three proposed Ran effectors, Ran-binding protein 1 (RanBP1), Ran-binding protein 2 (RanBP2, a nucleoporin), and karyopherin beta (a component of the nuclear protein import pathway), and is not stimulated to hydrolyze bound GTP by Ran GTPase-activating protein, RanGAP1. Also in contrast to wild-type Ran, T42A-Ran does not stimulate nuclear protein import in a digitonin permeabilized cell assay and also inhibits wild-type Ran function in this system. However, the T42A mutation does not block the docking of karyophilic substrates at the nuclear pore. These properties of T42A-Ran are consistent with its classification as an effector mutant and define the exposed region of Ran containing the mutation as a probable effector loop. 相似文献
148.
149.
150.
MG DeCastro GA Denys LL Fauerbach JK Ferranti K Hawkins LC Masters D Rimland RJ Sharbaugh J Zeller 《Canadian Metallurgical Quarterly》1999,27(1):54-55
The Association for Professionals in Infection Control and Epidemiology, Inc (APIC), is a multidisciplinary, voluntary, international organization of professionals who practice infection control and the application of epidemiology in all health settings. APIC is an international leader in prevention and control of infection transmission. 相似文献