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排序方式: 共有1133条查询结果,搜索用时 15 毫秒
51.
Hombach S Janssen-Bienhold U Söhl G Schubert T Büssow H Ott T Weiler R Willecke K 《The European journal of neuroscience》2004,19(10):2633-2640
Horizontal cells are interneurons of the vertebrate retina that exhibit strong electrical and tracer coupling but the identity of the channel-forming connexins has remained elusive. Here we show that horizontal cells of the mouse retina express connexin57 (Cx57). We have generated Cx57-deficient mice by replacing the Cx57 coding region with a lacZ reporter gene, expressed under control of the endogenous Cx57 promoter. These mice were fertile and showed no obvious anatomical or behavioural abnormalities. Cx57 mRNA was expressed in the retina of wild-type littermates but was absent from the retina of Cx57-deficient mice. Previously reported results that the Cx57 gene was very weakly expressed in several other mouse tissues turned out to be unspecific. Cx57 mRNA is abundantly expressed in the retina and weakly in the thymus of adult mice but absent in all other adult tissues tested, including brain. Furthermore, Cx57 is expressed in embryonic kidney at E16.5 to E18.5 days post-conception, as indicated by the pattern of lacZ expression. Within the retina, lacZ signals were assigned exclusively to horizontal cells based on co-localization with cell-type-specific marker proteins. Microinjection of Neurobiotin into horizontal cells of isolated retinae revealed less than 1% of tracer coupling in Cx57-deficient retinae compared with wild-type controls. Cx57 is the first connexin identified in mammalian horizontal cells and the first connexin whose expression is apparently restricted to only one type of neuron. 相似文献
52.
Wintermark M van Melle G Schnyder P Revelly JP Porchet F Regli L Meuli R Maeder P Chioléro R 《Radiology》2004,232(1):211-220
PURPOSE: To assess the prognostic value of admission perfusion computed tomography (CT) in patients with severe head trauma. MATERIALS AND METHODS: This prospective study included 130 patients with severe trauma, aged 19-86 years, admitted with a Glasgow Coma Scale score of 8 or less. They underwent perfusion CT as part of their admission CT survey. Clinical data, unenhanced cerebral CT findings, and perfusion CT scans were evaluated with respect to the Glasgow Outcome Scale (GOS) score at 3 months. Perfusion CT features were evaluated in patients with intracranial hypertension, cerebral contusions, and juxtadural hematomas. Ordered logistic regression was used to determine risk factors for an unfavorable GOS score at 3 months. RESULTS: Perfusion CT was more sensitive than conventional unenhanced CT in the detection of cerebral contusions. Perfusion CT featured specific patterns with respect to patient outcome, with normal brain perfusion or hyperemia in patients with favorable outcome, and oligemia in patients with unfavorable outcome. The number of arterial territories with low regional cerebral blood volume at perfusion CT was an independent prognostic factor (P =.008), as were mean arterial pressure at the scene of accident (P =.083), base excess at admission (P =.002), presence of skull fractures (P =.041), and signs of herniation (P =.013) at admission unenhanced cerebral CT. Perfusion CT also showed a range of brain perfusion alterations in patients with juxtadural collections, cerebral edema, or intracranial hypertension. CONCLUSION: Perfusion CT in patients with severe head trauma provides independent prognostic information regarding functional outcome. 相似文献
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Contamination by bacteria or fungi is a frequent problem with the in vitro isolation and propagation of protozoan parasites. We developed an antibiotic combination of broad anti-contaminant activity but minimal toxicity to protozoa. This anti-contamination cocktail consists of penicillin G (60 microgml(-1)), kanamycin (100 microgml(-1)), chloramphenicol (10 microgml(-1)) and flucytosine (50 microgml(-1)). It is well tolerated by African and South American trypanosomes, Leishmania spp., Giardia duodenalis, Entamoeba histolytica and Plasmodium falciparum, and it provides an effective means for the treatment of contaminated cultures. The anti-contamination cocktail meets numerous prophylactic applications in which sterile handling is impracticable or impossible. In particular, it facilitates the direct in vitro isolation of parasites from an infected host. 相似文献
56.
Oertli D Marti WR Zajac P Noppen C Kocher T Padovan E Adamina M Schumacher R Harder F Heberer M Spagnoli GC 《Human gene therapy》2002,13(4):569-575
A specific cellular immune response directed against a panel of three defined tumor-associated antigen (TAA) epitopes was induced in metastatic melanoma patients by a prime-boost strategy taking advantage of an innovative recombinant vaccinia virus as evaluated by quantitative assessment of cytotoxic T lymphocytes (CTLs) with corresponding specificity. The immunization protocol consisted of the administration of psoralen-UV-treated and replication-incompetent recombinant vaccinia virus encoding the three immunodominant HLA-A*0201-restricted epitopes Melan-A(27-35), gp100(280-288), and tyrosinase(1-9) together with two costimulatory molecules, B7.1 and B7.2, in the context of systemic granulocyte-macrophage colony-stimulating factor (GM-CSF) treatment. Boosts were subsequently applied with corresponding synthetic nonapeptides and GM-CSF. Specific CTL induction was assessed by tetramer staining and CTL precursor (CTLp) frequency evaluation. Within 12 days of injection of the recombinant vector, cytotoxic T cell responses specific for engineered epitopes were detectable in three of three patients. During the vaccination treatment, antigen-specific CTLp frequencies exceeding 1:10,000 peripheral CD8(+) T cells could be observed. Tetramer staining also revealed significant increases in specific CD8(+) T cell numbers. We conclude that active specific antitumor vaccination can raise a concurrent and specific cellular immune response against a panel of molecularly defined antigens, thereby increasing the chance of an immune hit against neoplastic cells with heterogeneous antigen expression. Data from this study emphasize the potency of a recombinant vaccinia virus vector encoding multiple minigenes and costimulatory molecules in the context of exogenously administered GM-CSF. Clinical effectiveness of this immunologically active protocol should therefore be explored in appropriately selected groups of patients. 相似文献
57.
BACKGROUND: To investigate the vasoactive effect of bimatoprost (Lumigan), a new topical ocular hypotensive agent, in isolated porcine ciliary arteries. MATERIAL AND METHODS: Arteries were placed in a myograph system to measure isometric forces. Quiescent vessels as well as vessels pre-contracted with either 10 nM endothelin-1 or 100 mM potassium chloride (KCl) were exposed, in a cumulative manner, to increasing concentrations (0.1 nM - 0.1 mM) of bimatoprost (dissolved in ethanol). In quiescent vessels, results were expressed in percent of 100 mM KCl-induced contraction. In endothelin-1-pre-contracted vessels, results were expressed in percent of the maximal contraction induced by endothelin-1. In KCl-pre-contracted vessels, results were expressed in percent of the plateau contraction reached 30 minutes after 100 mM KCl application. RESULTS: Bimatoprost induced a significant (p < 0.05 - 0.001) vasoconstriction at concentrations equal to or higher than 0.1 micro M in quiescent vessels (0.1 mM: 73 +/- 12 %). In KCl-pre-contracted vessels, at concentrations higher than 1 micro M, bimatoprost induced significant (p < 0.05 - 0.01) contractions (0.1 mM: 67 +/- 17 %). In endothelin-1-pre-contracted vessels, bimatoprost also induced significant (p < 0.05 - 0.001) contractions at concentrations above 10 micro M (0.1 mM: 17 +/- 8 %). CONCLUSIONS: The present study indicates that bimatoprost appears to have, in vitro, some vasoactive properties in porcine ciliary arteries. The question whether Lumigan has an influence on ocular blood flow needs to be further investigated. 相似文献
58.
Several novel derivatives bearing the 7-trifluoromethyl-4-(4-substituted anilino)-quinoline skeleton were synthesized and evaluated for their in vitro activity against the blood streaming form of the parasites Trypanosoma brucei rhodesiense, the trypomastigotes of Trypanosoma cruzi cultured in rat skeletal myoblasts, the amastigotes form of Leishmania donovani, Plasmodium falciparum (K1 strain) infected erythrocyte suspension, as well as their toxicity towards rat skeletal L-6 cells. In addition, three of the synthesized compounds were tested for their in vitro antitumor activity towards 60 human tumor cell lines by the National Cancer Institute (NCI). Compound 1-(4-[[7-(trifluoromethyl)quinolin-4-yl]amino]phenyl)ethan-1-one thiosemicarbazone 23 exhibited potential activity against T. b. rhodesiense, T. cruzi and P. falciparum with IC50's of 0.278, 0.85 and 0.417 microgram/ml, respectively. These values are even more valuable since this compound was clearly non-toxic (cytotoxicity IC50 > 90 micrograms/ml), leading to in vitro therapeutic indices of > 323, > 106 and > 216, respectively. Meanwhile, compound N-[4-[5-(4-chlorophenyl)-4,5-dihydroisoxazol-3-yl]phenyl]-7-(trifluoromethyl) quinolin-4-amine 21 showed broad spectrum antitumor activity with full panel median growth inhibition GI50 (MG-MID) of 1.95 mumol and total growth inhibition TGI (MG-MID) of 6.87 mumol, respectively. Compound 23 represents a very good prospective as a lead compound able to combat three tropical diseases at a time. However, the pattern for the antitumor activity did not parallel any of the antiparasitic ones, indicating that non-common mechanisms of action may exist among these activities. 相似文献
59.
Schmidt S Lepori D Meuwly JY Duvoisin B Meuli R Michetti P Felley C Schnyder P van Melle G Denys A 《European radiology》2003,13(6):1303-1311
Our objective was a prospective comparison of MR enteroclysis (MRE) with multidetector spiral-CT enteroclysis (MSCTE). Fifty
patients with various suspected small bowel diseases were investigated by MSCTE and MRE. The MSCTE was performed using slices
of 2.5 mm, immediately followed by MRE, obtaining T1- and T2-weighted sequences, including gadolinium-enhanced acquisition
with fat saturation. Three radiologists independently evaluated MSCTE and MRE searching for 12 pathological signs. Interobserver
agreement was calculated. Sensitivities and specificities resulted from comparison with pathological results (n=29) and patient's clinical evolution (n=21). Most pathological signs, such as bowel wall thickening (BWT), bowel wall enhancement (BWE) and lymphadenopathy (ADP),
showed better interobserver agreement on MSCTE than on MRE (BWT: 0.65 vs 0.48; BWE: 0.51 vs 0.37; ADP: 0.52 vs 0.15). Sensitivity
of MSCTE was higher than that of MRE in detecting BWT (88.9 vs 60%), BWE (78.6 vs 55.5%) and ADP (63.8 vs 14.3%). Wilcoxon
signed-rank test revealed significantly better sensitivity of MSCTE than that of MRE for each observer (p=0.028, p=0.046, p=0.028, respectively). Taking the given study design into account, MSCTE provides better sensitivity in detecting lesions
of the small bowel than MRE, with higher interobserver agreement.
Electronic Publication 相似文献
60.
Bringmann G Dreyer M Faber JH Dalsgaard PW Staerk D Jaroszewski JW Ndangalasi H Mbago F Brun R Reichert M Maksimenka K Christensen SB 《Journal of natural products》2003,66(9):1159-1165
The first phytochemical investigation of the recently discovered East African liana Ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines A (5) and B (6), and the known compound ancistrotectoriline A (7). Ancistrotazanine A (5) represents a hitherto unprecedented 5,3'-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8'-coupled. The structures of the compounds were determined by spectroscopic, chemical, and chiroptical methods. Compounds 5 and 6 showed good activities against the pathogens of leishmaniasis and Chagas' disease, Leishmania donovani and Trypanosoma cruzi, while 5-7 displayed moderately potent antiplasmodial activities against Plasmodium falciparum parasites. 相似文献