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排序方式: 共有191条查询结果,搜索用时 15 毫秒
21.
目的:研究铼.188标记生物分子在肿瘤治疗中的应用。方法:选取小白鼠作为实验的研究对象,将荷瘤鼠的肉瘤切成小块接种到小白鼠身上,达到试验条件时使用,即将没有明显差异的小白鼠16只随机分为4组,每组4只,注射含有铼一188的药物后分别在不同的时间将其处死,之后取出重要器官进行测量分析,进而得出铼一188的应用效果。结果:瘤内注射的要去在不同时间放射性在瘤内的保持率分别为(90.5±7.7)D%(1h),(92.2±8.6)D%(24h),(88.3±10.9)D%(48h)和(91.5±7.6)D%(72h),在荷瘤鼠内注入生理盐水、非放硫化铼和188Re.硫化铼混悬液,肿瘤质量分别为2885.3±1241.3、2839.9±1965.2和98.4±45.5mg。188Re-硫化铼混悬液在生理盐水、磷酸盐缓冲液和小牛血清中均可稳定72h,而且188W-188Re发生器的应用还可以降低188Re-硫化铼混悬液的价格。随着处死时间的延迟,小鼠肿瘤质量和体积逐渐减小,相临两组比较,后组测定值均明显小于前组,数据经统计学比较具有显著差异(P〈0.05)。结论:188Re-硫化铼混悬液是一种适宜的肿瘤治疗剂。 相似文献
22.
Background
In August 2006 a major epidemic of bluetongue virus serotype 8 (BTV8) started off in North-West Europe. In the course of 2007 it became evident that BTV8 had survived the winter in North-West Europe, re-emerged and spread exponentially. Recently, the European Union decided to start vaccination against BTV8. In order to improve the understanding of the epidemiological situation, it was necessary to execute a cross-sectional serological study at the end of the BT vector season. Cattle were the target species for cross-sectional serological studies in Europe at the end of 2006 and 2007. However, there was no information on the BTV8-seroprevalence in sheep and goats. 相似文献23.
This article correlates colonization with parameters, such as chemotaxis, biofilm formation, and bacterial growth, that are
believed to be connected. We show here, by using two varieties of soybean plants that seeds axenically produced exudates,
induced a chemotactic response in Bacillus amyloliquefaciens, whereas root exudates did not, even when the exudates, also collected under axenic conditions, were concentrated up to 200-fold.
Root exudates did not support bacterial cell division, whereas seed exudates contain compounds that support active cell division
and high cell biomass at stationary phase. Seed exudates of the two soybean varieties also induced biofilm formation. B. amyloliquefaciens colonized both seeds and roots, and plant variety significantly affected bacterial root colonization, whereas it did not
affect seed colonization. Colonization of roots in B. amyloliquefaciens occurred despite the lack of chemotaxis and growth stimulation by root exudates. The data presented in this article suggest
that soybean seed colonization, but not root colonization, by B. amyloliquefaciens is influenced by chemotaxis, growth, and biofilm formation and that this may be caused by qualitative changes of the composition
of root exudates. 相似文献
24.
25.
N L Kerber N L Pucheu A F García 《Biochemical and biophysical research communications》1978,81(2):667-671
Preillumination of chromatophores in the presence of phenazine methosulfate, under non-phosphorylating conditions results in an irreversible inhibition of the energy transduction. Protection against photoinhibition was provided during the preillumination when a continous dissipation of energy is provoked by the simultaneous photoreduction of NAD+. The results are interpreted as indicating that the photoinactivation is produced by an accumulation of the eergized form of the membrane. Different conformational forms of the ATPase complex are supposed to be responsible for the reversibility or irreversibility of the inhibited state. 相似文献
26.
Norma L. Pucheu Norma L. Kerber Emilio A. Rivas Néstor Cortez Augusto F. Garcia 《Current microbiology》1997,34(3):155-161
Membranes from in vivo labeled cells of Rhodobacter
capsulatus U43[pTX35] grown photosynthetically carried 60% of
the [32P]-Pi in the “heavy” fraction (HM) after
sucrose gradient sedimentation. Metal-chelating chromatography of either
“heavy” or “light” (LM) membrane fractions rendered
similar Bchl-protein complex profiles after octyl-glucoside treatment,
including most of the radioactivity in the same corresponding elution
fraction (F II). Similar labeling distribution of pigment-protein complexes
was obtained for membranes of dark-grown cells induced by lowering oxygen
tension. Fractions derived from HM showed highly labeled LHIα, whereas the
same complex from LM was essentially [32P]-Pi-free, as revealed
by SDS-PAGE followed by autoradiography. Phospholipid analysis showed a
similar pattern for membranes isolated from cells photosynthetically or
semiaerobically grown, being the most abundant: phosphatidylglycerol,
phosphatidylethanolamine, cardiolipin, and phosphatidylcholine. Part of the
phospholipids from HM comigrated with LHIα during SDS-PAGE and dissociated
from the complexes only after solvent extraction and hydrophobic
chromatography. However, a small amount remained always attached to LHIα,
indicating an unusual strong interaction. These results suggest the existence
of two operationally defined membrane regions carrying LHIα complexes
differing in phosphorylation status and protein-phospholipid interaction.
Received: 10 August 1996 / Accepted: 10 September 1996 相似文献
27.
William J. Meurer Brigid Rowell Devin Brown Alexander Tsodikov Angela Fagerlin Steven A. Telian Laura Damschroder Lawrence C. An Lewis B. Morgenstern Laura Loudermilk Sandeep Vijan Kevin A. Kerber 《Trials》2018,19(1):697
Background
Benign paroxysmal positional vertigo (BPPV) is the most common peripheral vestibular disorder, and accounts for 8% of individuals with moderate or severe dizziness. BPPV patients experience substantial inconveniences and disabilities during symptomatic periods. BPPV therapeutic processes – the Dix-Hallpike Test (DHT) and the Canalith Repositioning Maneuver (CRM) – have an evidence base that is at the clinical practice guideline level. The most commonly used CRM is the modified Epley maneuver. The DHT is the gold standard test for BPPV and the CRM is supported by numerous randomized controlled trials and systematic reviews. Despite this, BPPV care processes are underutilized.Methods/design
This is a stepped-wedge, randomized clinical trial of a multi-faceted educational and care-process-based intervention designed to improve the guideline-concordant care of patients with BPPV presenting to the emergency department (ED) with dizziness. The unit of randomization and target of intervention is the hospital. After an initial observation period, the six hospitals will undergo the intervention in five waves (two closely integrated hospitals will be paired). The order will be randomized. The primary endpoint is measured at the individual patient level, and is the presence of documentation of either the Dix-Hallpike Test or CRM. The secondary endpoints are referral to a health care provider qualified to treat dizziness for CRM and 90-day stroke rates following an ED dizziness visit. Formative evaluations are also performed to monitor and identify potential and actual influences on the progress and effectiveness of the implementation efforts.Discussion
If this study safely increases documentation of the DHT/CRM, this will be an important step in implementing the use of these evidenced-based processes of care. Positive results will support conducting larger-scale follow-up studies that assess patient outcomes. The data collection also enables evaluation of potential and actual influences on the progress and effectiveness of the implementation efforts.Trial registration
ClinicalTrials.gov, ID: NCT02809599. The record was first available to the public on 22 June 2016 prior to the enrollment of the first patients in October 2016.28.
29.
Lucas R Lopes Vitor AR Miranda Rodrigo A Goes Gabriel GA Souza Giuliana R Souza Jessica CS Rocha Victor RA Cossich Jamila A Perini 《Biology of sport / Institute of Sport》2021,38(4):703
The COVID-19 pandemic has presented significant challenges and implications for the sports community. Thus, this study aimed to describe the prevalence of COVID-19 in Brazilian athletes and identify the epidemiological, clinical, athletic, life and health factors associated with the disease in these individuals. A cross-sectional study was performed involving 414 athletes from 22 different sports using an online questionnaire from August to November 2020. The association between the athletes’ characteristics and COVID-19 was evaluated using a logistic regression model. The prevalence of COVID-19 was 8.5%, although only 40% of athletes reported having been tested. Being under 27 years of age (3-fold), having children (~5-fold), having a teammate test positive for COVID-19 (2.5-fold), and smoking (14-fold) were associated with a possible higher risk of disease. Almost 20% of athletes self-reported musculoskeletal injuries during the period of the pandemic that was studied. Athletes with a university education (P = 0.02), a profession other than sports (P < 0.001), those from a low-income family (P = 0.01), and public health system users (P = 0.04) were significantly less frequently tested for COVID-19, whereas international competitors, athletes who received a wage, and athletes who had a teammate who tested positive for COVID-19 were 2-, 3-, and 15-fold more likely to be tested for COVID-19, respectively. Approximately 26% of the athletes who tested negative or were untested reported more than three characteristic COVID-19 symptoms, and 11% of athletes who tested positive for COVID-19 were asymptomatic. The identification of modifiable (have children, smoking, and teammates positively tested) and non-modifiable (age under 27 years) factors related to COVID-19 in athletes can contribute to implementing surveillance programmes to decrease the incidence of COVID-19 in athletes and its negative impacts in sports. 相似文献
30.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246