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排序方式: 共有404条查询结果,搜索用时 15 毫秒
1.
Marchant D Gogat K Boutboul S Péquignot M Sternberg C Dureau P Roche O Uteza Y Hache JC Puech B Puech V Dumur V Mouillon M Munier FL Schorderet DF Marsac C Dufier JL Abitbol M 《Human mutation》2001,17(3):235
ABSTRACT We report five novel VMD2 mutations in Best's macular dystrophy patients (S16F, I73N, R92H, V235L, and N296S). An SSCP analysis of the VMD2 11 exons revealed electrophoretic mobility shifts exclusively in exons 2, 3, 4, 6 and 8. Direct sequencing indicated that these shifts are caused by mono-allelic transition in exons 2, 4, 6, 8 and transversion in exons 3 and 6. Five novel "silent" polymorphisms are also reported: 213T>C, 323C>A, 1514A>G, 1661C>T, and 1712T>C. Hum Mutat 17:235, 2001. 相似文献
2.
Systematic investigation of families of children suffering from retinoblastoma reveals more and more cases of retinoma or phthisis bulbi, cases which used to be called "spontaneous regression". Between 1975 and 1991, we have in this way discovered 11 cases (7%) certain to be carrying retinoma or phthisis bulbi, and a further 5 cases where the same diagnosis is highly probable. Of the 11 certain cases, 5 are unilateral, 6 bilateral, and 8 present family history of the disease. Of the total number of 17 eyes, 16 present retinoma, 1 phthisis bulbi. On clinical examination, all (100%) showed characteristic lesions in the form of greyish homogenous elevated masses in the vitreous cavity. 11 presented calcifications (69%) and in 14 disturbance of the pigment epithelium occurred (87%). The average follow-up is 4 years. Of the 11 patients, 8 are of procreating age and have up to now 25 offsprings. Amongst these, 15 have retinoblastoma (60%), 2 retinoma and phthisis bulbi (8%). All except one of the retinoblastoma cases are bilateral. This study would appear to show that retinoma occurs with a higher frequency than that which is usually given. The figures show clearly that retinoblastoma and retinoma derive from the same genetic disturbances, possibly at different times during cell maturation, and consequently require the same investigation and follow-up. 相似文献
3.
BACKGROUND: Despite an increased awareness among clinicians regarding pain and pain management for infants undergoing surgery, pain associated with procedures performed outside the operating room may not be adequately managed. PURPOSE: To examine the beliefs and self-described behavior of physicians and nurses regarding the management of procedural pain in newborn infants. METHODS: A survey was distributed to 467 clinicians (nurses and physicians) working in 11 level II and 4 level III nurseries in a large metropolitan area. Respondents were asked to rate the painfulness of 12 common bedside nursery procedures and how often pharmacologic and nonpharmacologic (comfort) measures are currently used and should be used for those procedures. Demographic data were also collected. RESULTS: Surveys were completed by 374 clinicians (80% response rate). Physicians and nurses believe infants feel as much pain as adults and that 9 of the 12 listed procedures are moderately to very painful. Neither pharmacologic nor comfort measures are believed to be used frequently, even for the most painful procedures. Physicians and nurses believe both pharmacologic and comfort measures should be used more frequently, but nurses believe comfort measures should be used more frequently than do physicians. Beliefs about infant pain and procedural pain were related to pain management preferences. Physicians' but not nurses' ratings were associated with significant personal pain. CONCLUSIONS: Despite their beliefs that infants experience significant procedure-related pain, clinicians believe pain management for infants remains below optimal levels. Barriers to more consistent and effective pain management need to be identified and surmounted. 相似文献
4.
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
5.
双波长薄层扫描法测定痛得安胶囊中新乌头碱的含量 总被引:3,自引:0,他引:3
目的:建立痛得安胶囊中新乌头碱的含量测定方法。方法:采用双波长薄层扫描法,以正己烷-乙酸乙酯-无水乙醇-氨水(12:8:2.5:0.5)为展开剂,碘化饿钾试液为显色剂,测定该制剂中新乌头碱的含量。结果:线性范围为1~6ug。平均回收率为94.80%,RSD为2.03%。结论:本法操作简便。结果可靠。实用,适合该制剂中新乌头碱的含量测定。 相似文献
6.
Early proliferation of CCR5(+) CD38(+++) antigen-specific CD4(+) Th1 effector cells during primary HIV-1 infection 总被引:4,自引:0,他引:4 下载免费PDF全文
Zaunders JJ Munier ML Kaufmann DE Ip S Grey P Smith D Ramacciotti T Quan D Finlayson R Kaldor J Rosenberg ES Walker BD Cooper DA Kelleher AD 《Blood》2005,106(5):1660-1667
We investigated whether HIV-1 antigen-specific CD4(+) T cells expressed the viral coreceptor CCR5 during primary HIV-1 infection (PHI). In the peripheral blood of subjects with very early PHI (< 22 days after onset of symptoms), there was a 10- to 20-fold increase in the proportion of highly activated (CD38(+++)) and proliferating (Ki-67(+)) CD4(+) T cells that expressed CCR5(+), and were mostly T-cell intracellular antigen-1 (TIA-1)(+) perforin(+) granzyme B(+). Inthe same patient samples, CD4(+) T cells producing interferon (IFN)-gamma in response to HIV group-specific antigen (Gag) peptides were readily detected (median, 0.58%) by intracellular cytokine assay-these cells were again predominantly CD38(+++), Ki-67(+), and TIA-(++), as well as Bcl-2(low). On average, 20% of the Gag-specific CD4(+) T cells also expressed interleukin-2 (IL-2) and were CD127 (IL-7R)(+). Taken together, these results suggest that Gag-specific T-helper 1 (Th1) effector cells express CCR5 during the primary response and may include precursors of long-term self-renewing memory cells. However, in PHI subjects with later presentation, antigen-specific CD4(+) T cells could not be readily detected (median, 0.08%), coinciding with a 5-fold lower level of the CCR5(+)CD38(+++) CD4(+) T cells. These results suggest that the antiviral response to HIV-1 infection includes highly activated CCR5(+)CD4(+) cytotoxic effector cells, which are susceptible to both apoptosis and cytopathic infection with HIV-1, and rapidly decline. 相似文献
7.
Mineralocorticoid receptor (MR), highly expressed in the hippocampus, binds corticosteroid hormones and coordinately participates, with the glucocorticoid receptor, to the control of stress responses, memorization, and behavior. To investigate the impact of MR in neuronal survival, we generated murine embryonic stem (ES) cells that overexpress human MR (hMR) (P1-hMR) and are induced to differentiate into mature neurons. We showed that recombinant MR expression increased throughout differentiation and is 2-fold higher in P1-hMR ES-derived neurons compared with wild-type controls, whereas glucocorticoid receptor expression was unaffected. Although proliferation and early neuronal differentiation were comparable in P1-hMR and wild-type ES cells, MR overexpression was associated with higher late neuronal marker expression (microtubule-associated protein 2 and β-tubulin III). This was accompanied by a shift towards neuron survival with an increased ratio of anti- vs. proapoptotic molecules and 50% decreased caspase 3 activity. Knocking down MR overexpression by small interfering RNA drastically reversed neuroprotective effects with reduced Bcl(2)/Bax ratio and decreased microtubule-associated protein 2 expression. P1-hMR neurons were protected against oxidative stress-induced apoptosis through reduced caspase 3 activation and drastically increased Bcl(2)/Bax ratio and β-tubulin III expression. We demonstrated the involvement of MR in neuronal differentiation and survival and identify MR as an important neuroprotective mediator opening potential pharmacological strategies. 相似文献
8.
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10.
Identification of circulating antigen-specific CD4+ T lymphocytes with a CCR5+, cytotoxic phenotype in an HIV-1 long-term nonprogressor and in CMV infection 下载免费PDF全文
Zaunders JJ Dyer WB Wang B Munier ML Miranda-Saksena M Newton R Moore J Mackay CR Cooper DA Saksena NK Kelleher AD 《Blood》2004,103(6):2238-2247
Antigen-specific CD4+ effector T cells primarily provide help for B-cell antibody responses and CD8+ cytotoxic T-lymphocyte (CTL) responses. We have found an expanded population of HIV-1 p24-specific, T-cell receptor V beta 17+, CD4+ T lymphocytes, defined by in vitro proliferative and interferon-gamma responses to a 15-mer Gag peptide, in the peripheral blood of an individual with long-term nonprogressive HIV-1 infection. Ex vivo, these cells were CCR5+ and CCR7-, consistent with an effector/memory function. Surprisingly, these cells highly expressed several proteins characteristic of cytotoxic lymphocytes, including TIA-1 (T-cell intracellular antigen 1; GMP-17/NKG7), granzymes A and B, CD161 (NKRP-1), and CD244 (C1.7/2B4). Following in vitro peptide stimulation, these cells produced interleukin 2 (IL-2) and intracellular CD40L, suggesting possible helper function, in addition to induction of perforin and cytotoxicity. A subset of cytomegalovirus (CMV)-specific CD4+ T cells in healthy adults similarly expressed these CTL markers and CCR5, ex vivo. Furthermore, this distinct subset of CD4+ T cells was significantly elevated in healthy CMV-seropositive adults, compared with CMV-seronegative individuals. These results suggest that CCR5+ CD4+ CTL may be a major effector mechanism of the immune response to viral infections in humans. Moreover, expression of CCR5 may render them particularly susceptible to cytopathic effects during progressive HIV-1 infection. 相似文献