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排序方式: 共有517条查询结果,搜索用时 203 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
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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
9.
Ernest Massiah Timothy C Roach Carol Jacobs Anne M St John Vashti Inniss Jerome Walcott Chris Blackwood 《Pan American journal of public health》2004,16(6):395-401
OBJECTIVE: To determine the extent of clinical knowledge of HIV/AIDS that physicians in Barbados have and their attitudes towards persons living with HIV/AIDS. METHODS: In 2000 the Barbados Association of Medical Practitioners conducted a survey in order to assess its members' views on HIV/AIDS issues. Over a two-month period 203 physicians (76% of all those practicing in the country) were interviewed. The survey included physicians working in private practice and the public sector. They were surveyed individually concerning their attitudes towards counseling as well as their clinical knowledge, perception of safe practices, fear of occupational exposure, views on ethical issues, experience treating HIV/AIDS patients, and background with HIV/AIDS continuing education. RESULTS: In comparison to physicians who had graduated in later years, physicians who had graduated in 1984 or earlier had seen fewer HIV/AIDS clients, had lower levels of knowledge about the disease, were more likely to test for HIV/AIDS without informed consent, and were less likely to have ever attended a continuing education training course on HIV/AIDS. Overall, knowledge of the clinical indications of HIV/AIDS was low, and 76% of the physicians did not think they had adequate counseling skills. Over 80% of the physicians were comfortable looking after HIV/AIDS patients. While 95% of the physicians would not release HIV test results without a patient's consent, 33% would test, without consent, a seriously ill patient, and 15% would test without consent a patient upon whom they had to perform an invasive procedure if they perceived the patient to be from a high-risk population such as gay men or commercial sex workers. Only 53% of the physicians had attended an HIV/AIDS in-service training program between 1995 and 1999. CONCLUSIONS: Physician training in Barbados should focus on all aspects of HIV/AIDS care, including clinical and emotional factors. Attendance at such training should be mandatory for public sector physicians, and medical school curricula need to be examined to ensure their HIV/AIDS content is current and comprehensive. 相似文献
10.
The expression of pain serves as a way for animals to communicate potential dangers to nearby conspecifics. Recent research demonstrated that mice undergoing alcohol or morphine withdrawal, or inflammation, could socially communicate their hyperalgesia to nearby mice. However, it is unknown whether such social transfer of hyperalgesia can be observed in other species of rodents. Therefore, the present study investigated if the social transfer of hyperalgesia occurs in the highly social prairie vole (Microtus ochrogaster). We observe that adult female prairie voles undergoing withdrawal from voluntary two-bottle choice alcohol drinking display an increase in nociception. This alcohol withdrawal-induced hypersensitiity is socially transferred to female siblings within the same cage and female strangers housed in separate cages within the same room. These experiments reveal that the social transfer of pain phenomenon is not specific to inbred mouse strains and that prairie voles display alcohol withdrawal and social transfer-induced hyperalgesia. 相似文献