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1.
Turnbull Chris D. Stockley James A. Madathil Shyam Huq Syed S. A. Cooper Brendan G. Ali Asad Wharton Simon Stradling John R. Heitmar Rebekka 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2022,260(7):2129-2139
Graefe's Archive for Clinical and Experimental Ophthalmology - Retinal microvascular endothelial dysfunction is thought to be of importance in the development of ocular vascular diseases.... 相似文献
2.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
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Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
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Chaperonin-mediated assembly of wild-type and mutant subunits of human propionyl-CoA carboxylase expressed in Escherichia coli 总被引:1,自引:0,他引:1
We developed a bacterial expression system for the human alpha and beta
cDNAs of propionyl-CoA carboxylase (PCC). These cDNAs (less the putative
mitochondrial matrix targeting presequences) were co-expressed in
Escherichia coli on one plasmid vector with each cDNA having its own
IPTG-inducible promoter. Only negligible amounts of active PCC were
measured despite the presence of both alpha and beta subunits as indicated
by Western blot analysis and the almost complete biotinylation of the alpha
subunit. Co-expression of this plasmid with a second plasmid vector
over-expressing the E. coli chaperonin proteins, groES and groEL, resulted
in a several hundred-fold increase in PCC specific activity, to a level
comparable with that found in crude human liver extracts. PCC was partially
purified on monomeric avidin affinity resin and the presence of both alpha
and beta subunits was demonstrated, thereby confirming the assembly of both
subunits into an active enzyme. Deficiency of either alpha PCC or beta PCC
results in propionic acidemia, an autosomal recessive disorder. We used
this expression system to characterize one missense mutation previously
described in five Japanese alleles, namely C1283T (Thr428lle) in beta PCC.
This mutation, when expressed in E.coli under the same conditions as that
of wild-type PCC, had null activity, despite the presence of assembled
alpha PCC and beta PCC subunits. This bacterial expression system can be
useful for analysis of either alpha PCC or beta PCC mutations. Our findings
indicated that the groES and groEL chaperonin proteins were essential for
folding and assembly of the human PCC heteromeric subunits.
相似文献
9.
Activities and sources of beta-lactamase in sputum from patients with bronchiectasis. 总被引:2,自引:0,他引:2 下载免费PDF全文
P Dragicevic S L Hill D Burnett D Merrikin R A Stockley 《Journal of clinical microbiology》1989,27(5):1055-1061
beta-Lactamase activity was measured in secretions from patients with bronchiectasis. Of 28 sputum samples, 23 contained measurable amounts of activity; values were significantly higher (P less than 0.01) in purulent samples than in mucoid or mucopurulent samples. beta-Lactamase activity was usually present in saliva collected before and between sputum expectorations, although values for sputum were higher than for either group of saliva samples (P less than 0.025 and P less than 0.005, respectively). This difference suggests that at least part of sputum beta-lactamase activity originates in the bronchial tree. Detailed microbiological study of a further eight specimens (seven were beta-lactamase positive) led to the isolation of Haemophilus influenzae from six, although only two of these isolates were beta-lactamase positive. Several other beta-lactamase-producing organisms were also isolated, including Staphylococcus aureus (n = 3), Escherichia coli (n = 1), Proteus spp. (n = 1), and Bacteroides spp. (n = 3). Size-exclusion high-performance liquid chromatography of the sputum showed several peaks of beta-lactamase activity which usually coeluted in fractions similar to those of their beta-lactamase-positive isolates. Therefore, sources of sputum beta-lactamases are often bacteria not considered truly pathogenic or not isolated during routine bacteriological assessment. These observations should be considered when embarking on antimicrobial therapy in bronchiectatic patients and suggest that increased dosages of penicillins are indicated. 相似文献
10.
There is a significant fall in PMN chemotaxis to the peptide FMLP in response to increasing concentrations of dexamethasonein vitro. The response fell in a dose related manner from a control value of 53.7 SE±9.6 cells per high power field (cpf) to 47.3 SE±8.1 at 10–6
M (p<0.05) and 24.7±8.9 at 10–3
M (p<0.025). A similar response was observed for the chemoattractants zymosan activated serum and the sol phase of purulent sputum. The effect was independent of protein synthesis or the period of incubation. Twelve milligrams of dexamethasone taken daily by 6 healthy volunteers resulted in a significant (p<0.025) reduction in the chemotactic response of PMN to 10–8
M FMLP (from 29.5±1.55 to 13.7±1.8 cpf) which was apparent within 2 hours of taking the first dose. This effect was sustained for the three days on which dexamethasone was taken but returned to normal 7 days after the last dose had been administered.Dexamethasone therapy had no effect on unstimulated PMN superoxide anion production eitherin vitro orin vivo.Thein vivo effect on neutrophil function occurred at mean serum dexamethasone concentrations of 1.26 (±0.28)×10–7
M on day 1, 1.44 (±0.15)×10–7
M on day 2 and 1.31 (±0.13)×10–7
M on day 3. Thus we conclude that dexamethasone concentration which inhibit PMN chemotaxisin vivo are much lower than those required to exert the same effectin vitro. 相似文献