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排序方式: 共有504条查询结果,搜索用时 15 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
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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
6.
Tiacci C. D'Alessandro P. Cantisani T. A. Bartocci A. Ibba A. Ferroni A. 《The Italian Journal of Neurological Sciences》1995,16(4):279-294
In 1945, Lennox was the first to describe the epileptic states mainly expressed by various degrees of consciousness disturbance, which have their onset in children who present epileptic absences correlated with ictal EEG patterns of spike-wave complex discharges at about 3 Hz. As the clinical picture seemed to be similar to an uninterrupted series of absences, this led to the definition Petit Mal Status (PMS). Many authors have subsequently reported that PMS can occur in epileptic subjects who have never presented absences (and even in subjects without a previous history of epilepsy) and that the related EEG pictures were characterised by paroxysmal generalized activity of various morphology, but hardly ever consisted of the continuous rhythmic spike-wave or polyspike-wave complexes at 3 Hz found in petit mal absences. Finally, in reporting the onset and recurrence of this condition typically in adults and the elderly, some authors have proposed the existence of a particular form of PMS (dependent on different types of pathologic factors and characterising a specific syndrome of this age) that is different from that of the real PMS typical of childhood and related to petit mal absences. This paper describes fifteen patients in whom the onset of the condition occurred at different ages, and who seem to exemplify the various possible clinical expressions of PMS, with the aim of making a contribution towards the better nosographic definition of this epileptic condition.On the basis of our study, we sustain that the so-called PMS is a seizure type of Idiopathic Generalized Epilepsy which may appear at nearly all ages, and may occur in isolation or in association with other epileptic manifestations, but cannot itself be considered as characterising one or more age-dependent syndromes.
Sommario Lennox per primo (1945) descrisse degli Stati Epilettici esprimentisi principalmente con un disturbo della coscienza di grado variabile, insorgenti in bambini che presentavano Assenze epilettiche, correlati con pattern EEG ictale di scariche di complessi PO a circa 3 Hz. Il quadro clinico sembrava pertanto poter essere assimilato al susseguirsi ininterrotto di Assenze, donde la definizione di Petit Mal Status (PMS). Successivamente molti Autori hanno segnalato che il PMS poteva ricorrere in soggetti epilettici che non avevano mai presentato Assenze o, addirittura, in soggetti senza precedenti di Epilessia, e che i quadri EEG correlati erano caratterizzati da attività pasossistiche generalizzate di varia morfologia, ma quasi mai costituiti da complessi PO e PPO ritmici continui a 3 Hz, come nelle Assenze del Piccolo Male. Alcuni Autori, infine, nel segnalare l'esordio e la ricorrenza di tale condizione tipicamente in età adulta e avanzata, hanno proposto la individuazione di una particolare forma di PMS, dipendente da fattori patologici di vario genere, caratterizzanti una sindrome specifica di questa età, diversa da quella del vero PMS tipico della infanzia e correlato con le Assenze del Piccolo Male.In questo lavoro viene proposta la descrizione di quindici casi esorditi alle varie età, che sembrano paradigmatici delle varie possibili espressioni cliniche del PMS, allo scopo di contribuire ad una migliore definizione nosografica di tale condizione epilettica. Sulla base di questa esperienza gli Autori sostengono che il cosiddetto PMS si configura come un tipo di crisi dell'Epilessia Generalizzata Idiopatica, che può insorgere in quasi tutte le età della vita e presentarsi isolato ovvero associato ad altre manifestazioni epilettiche, senza che di per sè possa caratterizzare una o più Sindromi età-dipendenti.相似文献
7.
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
8.
We studied whether the administration of piracetam in acute, presumed ischemic stroke affects case fatality and functional
outcome. The Cochrane Stroke Group strategy was used to evaluate all randomized controlled trials of patients with presumed
ischemic stroke examined within 48 h; death and (when available) functional outcome were used as end points. Three studies
were included; the most recent one contributed more than 97% of the data. There were 501 patients treated with piracetam and
501 controls. Piracetam was associated with a nonsignificant 31% increase in the odds of death (95% CI –5% to 81%). This result
was due almost completely to the effect of the larger trial, which, however, reported that the difference in case fatality
rate between piracetam and control disappeared after correcting for the imbalance in stroke severity between the two groups.
Data on functional outcome were available only for the largest study, and no difference was reported. Data obtained from the
manufacturer suggested a nonsignificant trend (–10%) towards reduction in dependency with piracetam (CI –33% to 20%); the
proportions of patients dead or dependent in the two groups were the same. Relevant adverse effects were not reported. The
evidence from this review does not support routine administration of piracetam in patients with acute ischemic stroke; however,
since a possible beneficial effect cannot completely be ruled out, further controlled trials are warranted.
Received: 31 August 1999/Received in revised form: 3 November 1999/Accepted: 25 November 1999 相似文献
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MR imaging features of solid pseudopapillary tumor of the pancreas in adult and pediatric patients 总被引:24,自引:0,他引:24
Cantisani V Mortele KJ Levy A Glickman JN Ricci P Passariello R Ros PR Silverman SG 《AJR. American journal of roentgenology》2003,181(2):395-401
OBJECTIVE: This study was conducted to describe the MR imaging features of solid pseudopapillary tumor of the pancreas. CONCLUSION: Solid pseudopapillary tumor of the pancreas, a tumor typically seen in young women, is a large, well-defined, encapsulated lesion with heterogeneous high or low signal intensity on T1-weighted, heterogeneous high signal intensity on T2-weighted, and early peripheral heterogeneous enhancement with progressive fill-in on gadolinium-enhanced dynamic MR imaging. These features help differentiate this rare tumor from other pancreatic neoplasms. 相似文献