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The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.  相似文献   
33.

Antibiotics, which can be used as veterinary drugs, are widely used in the prevention and treatment of infectious diseases for animals. However, overuse of antibiotics had caused serious problems on food contamination and human harm. For control such public issues, several of techniques have been in recent years. Ratiometric fluorescent (RF) technique, as one of the most promising strategies for quantitatively evaluated analytes, had been extensively developed for the readily measurements on the two different fluorescent emission intensities. In this review, the construction strategies for recent RF sensors will be mainly focused on. Meanwhile, the recent advances and new tendencies for detection of antibiotics based on RF technique shall be introduced. Finally, outlooks on the opportunities and challenges for quantitative fluorescence sensing on antibiotics will be summarized.

  相似文献   
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Bulletin of Environmental Contamination and Toxicology - For the immense requirement on agriculture and animal husbandry, application of pesticides and veterinary drugs had become a normal state in...  相似文献   
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目的 对湖南侗族左扣手人群的掌纹分布特点进行研究 ,积累侗族群体遗传学与民族学资料。方法用油墨拓印法捺印手纹 ,放大镜下观察分析。结果侗族左交臂人的普通型及过渡Ⅱ型掌褶纹的百分率存在明显的性差 (p <0 0 1) ;TH/I1区及I3 区的真实花纹出现率在左右手之间存在明显差异 (p <0 0 5或p <0 0 1)。过渡Ⅰ型掌褶纹的百分率与对照组比较存在明显的差异 (p <0 0 5 )。结论湖南侗族左交臂人群的掌纹有其自身的特征  相似文献   
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联合应用热双蒸水、生理盐水、右旋糖酐40 序贯腹腔冲洗的方法,行体外试验与动物试验。发现45 ℃双蒸水浸泡腹腔20 min 后能完全杀灭体外培养的B6F10 细胞;右旋糖酐40 部分抑制B16F10 细胞对胶化培养板孔壁的粘附。小鼠腹腔注入B16F10 细胞后,按上述三联合液序贯冲洗可预防70 % 的C57 BL/6j小鼠发生腹膜癌病,未见毒副作用。在此冲洗的基础上,腹腔内保留氯氨铂,疗效高达88-9 % ,但毒性也增加  相似文献   
38.
A follow-up study was carried out of 16 SSPE patients two years after completion of 6-month treatment with Antineoplaston. The study was based on an inquiry sent to the families of the patients and on control examinations at the clinic. In the period of follow-up 6 patients died, all had the downhill type of disease course and their mean survival was 18 months. Out of the remaining 10 patients 4 are in stationary condition and the remaining ones had minimal worsening. A more detailed clinical analysis showed that half the patients were in contact with and general orientation in the environment, but impairment of motor functions made difficult in most cases self-care and self-dependent functioning. All patients had evident changes in brain MRI. The survival time of the patients has been as yet from 2.5 to 5.5 years (mean 3.9 years). The results of the treatment with Antineoplaston AS2-1 + isoprinosine are comparable with those observed during isoprinosine alone treatment but significantly worse than those after administration of Propionibacterium granulosum with isoprinosine. This suggests that Antineoplaston AS2-1 fails to modify importantly the natural course of SSPE.  相似文献   
39.
Paraganglia are clusters of cells containing catecholamines (CA), mainly norepinephrine (NE) and dopamine (DA). The presence of epinephrine (E), on the other hand, has only been determined by indirect methods in retroperitoneal paraganglia of newborn and aged rats. Because their location, paraganglia associated with the hepatic branch of the vagus nerve may be a possible source of CA for the liver. The main purposes of the present study were to determine CA levels and whether E can be found in the omentum minus which includes paraganglia associated with the hepatic branch of the vagus nerve, and then to study the effects of 6-hydroxydopamine and reserpine on their CA content. Twenty-four female Wistar rats were randomly ascribed to three groups receiving two intraperitoneal injections of either 6-hydroxydopamine, reserpine or saline. Twenty-four hours after the last administration the rats were anesthetized and a portion of the omentum minus was obtained. Left adrenal medulla and a liver fragment were also collected as controls. The samples were processed to be analyzed by high performance liquid chromatography and catecholamine histofluorescence. The results confirm previous reports about the presence of considerable amounts of norepinephrine and dopamine in paraganglia. Norepinephrine and dopamine in the omentum like the adrenal medulla were significantly depleted by reserpine but not by 6-hydroxydopamine treatment, suggesting that some other sources in addition to sympathetic terminals are responsible for CA in the omentum. On the contrary, both drugs reduced liver NE, consistent with the localization of this amine mainly to hepatic sympathetic terminals. Histofluorescence of the omentum revealed 2-4 paraganglia per tissue fragment. Paraganglia associated with the hepatic branch of the vagus nerve contain also E. The presence of perihepatic sources of extra-adrenal CA, and more specifically E, could be of physiological significance.  相似文献   
40.
BACKGROUND: Aluminum (Al3+) has diverse biological effects mediated through activation of a putative extracellular cation-sensing receptor. A recently identified calcium-sensing receptor (CaSR), which has been identified in target tissues for Al3+, may transduce some of the biological effects of Al3+. METHODS: To test this possibility, we transfected human embryonic kidney 293 (HEK 293) cells with a cDNA encoding the rat CaSR and evaluated CaSR expression by Western blot analysis and function by measurement of intracellular calcium ([Ca2+]i) levels and inositol monophosphate (IP1) generation following stimulation with Al3+ and a panel of CaSR agonists. RESULTS: The CaSR protein was detected by immunoblot analysis in cells transfected with the CaSR cDNA but not in nontransfected HEK 293 cells. In addition, [Ca2+]i levels and IP1 generation were enhanced in a dose-dependent fashion by additions of the CaSR agonists calcium (Ca2+), magnesium (Mg2+), gadolinium (Gd3+), and neomycin only in cells transfected with CaSR. To determine if Al3+ activated CaSR, we stimulated cells transfected with rat CaSR with 10 microM to 1 mM concentrations of Al3+. Concentrations of Al3+ in the range of 10 microM to 100 microM had no effect on [Ca2+]i levels or IP1 generation. In contrast, 1 mM Al3+ induced small but significant increases in both parameters. Whereas Gd3+ antagonized calcium-mediated activation of CaSR, pretreatment with Al3+ failed to block subsequent activation of rat CaSR by Ca2+, suggesting a distinct mechanism of Al3+ action. CONCLUSION: Al3+ is not a potent agonist for CaSR. Because Al3+ affects a variety of target tissues at micromolar concentrations, it seems unlikely that CaSR mediates these cellular actions of Al3+.  相似文献   
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