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排序方式: 共有598条查询结果,搜索用时 46 毫秒
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GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
4.
Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
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Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献
7.
S Ladas G Arapakis H Malamou-Ladas G Palikaris A Arseni 《Journal of clinical pathology》1979,32(11):1163-1167
It was postulated that the short chain fatty acids (SCFA) produced by anaerobic bacteria might serve as microbial markers in purulent material. Eighteen pus specimens from various sources were analysed by gas-liquid chromatography (GLC), and the SCFA detected were compared with the microorganisms isolated by conventional methods. It was found that the detection of propionic, isobutyric, butyric, or isovaleric acids by direct GLC of pus specimens is strong evidence for anaerobic infection but not specific for Bacteroides fragilis. It was also shown that the presence of succinic acid in pus specimens does not necessarily indicate infection by anaerobes. It can be concluded that direct GLC of purulent material provides a rapid and reliable presumptive method for the differentiation between anaerobic and aerobic infections. 相似文献
8.
Effect of surface roughness of the titanium alloy Ti-6Al-4V on human bone marrow cell response and on protein adsorption 总被引:5,自引:0,他引:5
Deligianni DD Katsala N Ladas S Sotiropoulou D Amedee J Missirlis YF 《Biomaterials》2001,22(11):1241-1251
The effect of surface roughness of the titanium alloy Ti-6Al-4V (Ti alloy) on the short- and long-term response of human bone marrow cells in vitro and on protein adsorption was investigated. Three different values in a narrow range of surface roughness were used for the substrata (R(alpha): 0.320, 0.490 and 0.874 microm). Cell attachment, cell proliferation and differentiation (alkaline phosphatase specific activity) were determined past various incubation periods. The protein adsorption of bovine serum albumin and fibronectin, from single protein solutions, on rough and smooth Ti alloy surfaces was examined with two methods, X-ray photoelectron spectroscopy (XPS) and radiolabeling. Cell attachment and proliferation were surface roughness sensitive and increased as the roughness of Ti alloy increased. No statistically significant difference was observed in the expression of ALP activity on all three Ti alloy surfaces and culture plastic. Both methods, XPS and protein radiolabeling, showed that human serum albumin was adsorbed preferentially onto the smooth substratum. XPS technique showed that the rough substratum bound a higher amount of total protein (from culture medium supplied with 10% serum) and fibronectin (10-fold) than did the smooth one. The cell attachment may be explained by the differential adsorption of the two proteins onto smooth and rough Ti alloy surfaces. 相似文献
9.
Abril N; Luque-Romero FL; Prieto-Alamo MJ; Rafferty JA; Margison GP; Pueyo C 《Carcinogenesis》1997,18(10):1883-1888
Here we confirm and extend our previous studies demonstrating that the
mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is
markedly enhanced (not prevented) in bacteria expressing the O6-
alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli
ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt
ATase sensitizes the bacteria to the lethal effects of these carcinogens,
suggesting that one or more of the potentially mutagenic lesions induced by
DBE and DBM in the presence of Ogt has additional lethal capacity. We
further demonstrate that the sensitization to both lethality and
mutagenesis by DBE and DBM is a property shared by other DNA
alkyltransferases. This objective was accomplished by quantifying the
induction of mutations and lethal events in ogt- ada- E. coli expressing an
exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian
recombinant ATases enhanced the lethal and mutagenic actions of DBE and
suppressed the lack of sensitivity of the vector- transformed bacteria to
DBM. In most cases the order of effectiveness of the ATases ranked: murine
> human > Ogt > rat. Further comparisons included the full-length
Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the
O6-methylguanine binding domain of the protein. The full-length Ada ATase
was effective in enhancing the lethality but not the mutagenicity induced
by DBE and DBM. The T-ada ATase provided less sensitization than Ada to
lethality by DBE, but of the three bacterial ATases T-ada yielded the
highest sensitization to mutagenesis by this compound. T-ada and Ada ATases
were in general less effective than the mammalian versions, with the
exception of the rat recombinant ATase. The effectiveness of the different
mammalian and bacterial ATases in promoting the deleterious actions of
dibromoalkanes was compared with the effectiveness of these proteins in
suppressing the lethal and mutagenic effects induced by
N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and
mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase,
since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt-
ada- cells showed no effect, in spite of the reported potential of
bioactive dihaloethane- derived species to alkylate Trx.
相似文献
10.
目的:通过对老年人进行血浆溶血磷脂酸和磷脂酸的筛检,从而认识血浆溶血磷脂酸和磷脂酸在血栓预防中的作用。方法:对2004-04/07期间的1657名和2005-04/07期间的1748名离休干部进行血浆溶血磷脂酸和磷脂酸含量测定,并对溶血磷脂酸>3.0μmol/L和磷脂酸>5.0μmol/L的阳性人员进行药物干预。同时,选择2004年溶血磷脂酸和/或磷脂酸阳性人员119人,随机分为两组:①干预组(n=72):男63人,女9人,平均年龄78岁。口服阿司匹林100mg/d,持续1个月。②对照组(n=47):男42人,女5人,平均年龄76岁。干预后,测定两组血浆中溶血磷脂酸和磷脂酸的含量。结果:纳入对象全部进入结果分析。2005年磷脂酸及血浆溶血磷脂酸 磷脂酸阳性率均明显低于2004年(P<0.01),尤其是磷脂酸的阳性率降低的更为明显。2005年血浆溶血磷脂酸和磷脂酸的平均值均明显低于2004年(P<0.01)。干预组干预后血浆溶血磷脂酸和磷脂酸明显低于干预前及对照组(P<0.01)。结论:①血浆溶血磷脂酸和磷脂酸的测定可作为血栓预警和了解抗血栓药物疗效的一种手段。②阿司匹林干预后,血浆溶血磷脂酸和磷脂酸的含量均降低,可作为一种降低缺血性疾病发生率的有效途径。 相似文献