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31.
32.
Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics. 相似文献
33.
Madhotra D Fenton JE Makura ZG Charters P Roland NJ 《Irish journal of medical science》2004,173(4):197-199
Background The timing of aggressive airway intervention in adult epiglottitis is controversial.
Aims To correlate Friedman’s staging of epiglottitis on admission with the airway interventions undertaken.
Methods A retrospective study of 23 adult patients, mean age 51 years (range 29–81 years), who had been admitted with acute supraglottitis
between March 1988 and December 2000 was undertaken.
Results Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman
stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom
progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous
therapy.
Conclusions Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should
probably be lowered to those patients with rapid-onset stage III (moderate respiratory distress, stridor, respiratory rate
>30 per minute, pCO2 >45mmHg) disease. 相似文献
34.
35.
36.
Sequences from higher primates orthologous to the human Xp/Yp telomere junction region reveal gross rearrangements and high levels of divergence 总被引:2,自引:2,他引:2
A high level of sequence polymorphism combined with linkage disequilibrium
has created a limited number of highly diverged haplotypes across the human
Xp/Yp telomere junction region. To gain insight into the unusual genetic
characteristics of this region, we have examined the orthologous sequences
in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla)
and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp
sequence is higher (average 2.6-fold) than that observed at other loci. The
position of the human Xp/Yp telomere is unique, as additional sequences are
present at this location in the other three species. These included an
array of subterminal satellite in the chimpanzee and, in the gorilla a
small interstitial array of telomere-like repeats followed by sequences
with strong homology to the human 18p subterminal region. In the
orang-utan, two alleles with different structures were identified. These
differ by the presence or absence of a short interspersed nuclear element
(SINE) sequence just proximal to long arrays of telomere-like repeat
sequences that probably represent the proximal end of the orang-utan Xp/Yp
telomere. In addition, a high level of sequence divergence between the two
orang-utan structures was identified. This divergence is similar to that
observed between the human Xp/Yp telomere-adjacent haplotypes. The high
sequence divergence and evidence of gross rearrangements indicate that the
Xp/Yp telomeric region has evolved faster than the rest of the genome.
相似文献
37.
C. Sanfilippo D. Cambria A. Longo M. Palumbo R. Avola M. Pinzone G. Nunnari F. Condorelli G. Musumeci R. Imbesi P. Castogiovanni L. Malaguarnera Michelino Di Rosa 《Inflammation research》2017,66(12):1107-1116
Objective
The HIV-1 virus activates the complement system, an essential element of the immune system. SERPING1 is a protease inhibitor that disables C1r/C1s in the C1 complex of the classical complement pathway.Methods
In this paper, we performed an analysis of several microarrays deposited in GEO dataset to demonstrate that SERPING1 mRNA is modulated in CD14+ monocytes from HIV-1-infected individuals. In addition, data were validated on monocytes isolated from seronegative healthy volunteers, treated with IFNs.Results
Our analysis shows that SERPING1 mRNA is overexpressed in monocytes from HIV-1+ patients and the expression levels correlate positively with viral load and negatively with the CD4+ T-cell count. Of note, anti-retroviral therapy is able to reduce the levels of SERPING1 mRNA, ex vivo. In addition, we found that 30% of the SERPING1 genes network is upregulated in monocytes from HIV-1+ patients. Noteworthy, the expression levels of IFITM1—an antiviral molecule belonging to the genes network—correlate positively with SERPING1 expression. Interestingly, the monocytes treatment with IFN-gamma, IFN-beta and IFN-alpha significantly upregulates the SERPING1 mRNA expression levels.Conclusions
From the outcome of our investigation, it is possible to conclude that SERPING1 and its network serve as important components of the innate immune system to restrict HIV-1 infection.38.
39.
Rokey R; Verani MS; Bolli R; Kuo LC; Ford JJ; Wendt RE; Schneiders NJ; Bryan RN; Roberts R 《Radiology》1986,158(3):771-774
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium. 相似文献
40.
Montisci R Ruju C Massoni G Sanfilippo R Brotzu G 《The Journal of cardiovascular surgery》2003,44(2):249-253
AIM: Chronic venous ulcer treatment is often time consuming and requires a high degree of compliance from the patient. This derives not only from venous hypertension but also from chronic structural and metabolic changes of underlying tissues which impair the healing process. It therefore becomes necessary to improve the ulcer tissue condition in order to accelerate the healing process. This is obtained mainly with the improvement of local haemodynamics and secondly by direct action on the ulcer. The aim of the study is to evaluate the efficacy of a treatment with a pedunculated flap of fascia as an additional treatment of chronic venous ulcer. METHODS: Four patients classified C6 according to the CEAP classification were treated for chronic venous ulcer with correction of venous hypertension (saphenectomy or ligature of incompetent perforating veins). The patients also underwent rotation of a fascial pedunculated flap transferred from the sural area to the perimalleolar area. After 7-15 days they had a free skin graft in the treated area. RESULTS: All patients were discharged on the 3(rd) postoperative day after the flap rotation. In 3 patients the ulcer healed within 30 days and in a 4(th) patient within 45 days. No recurrence was observed. CONCLUSION: With this method the healing time seems to be shortened compared to the typical evolution in patients treated with only reflux control followed by conservative therapy. Associating fascial flap in the treatment of chronic venous ulcers improves the bed on which the free skin graft is applied. We can also hypothesize that this procedure restores the aponeurotic barrier between deep venous circulation and superficial microcirculation with the ensuing improvement in local venous hypertension. 相似文献