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排序方式: 共有475条查询结果,搜索用时 15 毫秒
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2.
In der Behandlung von Frakturen spielt die Analgesie eine wesentliche Rolle. Es stellt sich daher die Frage, ob in der Klinik h?ufig eingesetzte Analgetika wie Tramadol oder Diclofenac negative Wirkungen auf die Knochenbruchheilung haben. 相似文献
3.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
4.
Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献5.
Chen JJ Huang JC Shirtliff M Briscoe E Ali S Cesani F Paar D Cloyd MW 《Journal of leukocyte biology》2002,71(2):271-278
Recent studies have provided evidence that macrophages from Th1-prone mouse strains respond with an M1 profile, and macrophages from Th2-prone mouse strains respond with an M2 profile, characterized by the dominant production of NO or TGF-beta 1, respectively. We have shown that peritoneal macrophages from IL-12p40 gene knockout mice have a bias toward the M2 profile, spontaneously secreting large amounts of TGF-beta 1 and responding to rIFN-gamma with weak NO production. Moreover, IL-12p40KO macrophages are more permissive to Trypanosoma cruzi replication than their wild-type littermate cells. Prolonged incubation with rIL-12 fails to reverse the M2 polarization of IL-12p40KO macrophages. However, TGF-beta 1 is directly implicated in sustaining the M2 profile because its inhibition increases NO release from IL-12p40KO macrophages. IFN-gamma deficiency is apparently not the reason for TGF-beta 1 up-regulation, because rIFN-gamma KO macrophages produce normal amounts of this cytokine. These findings raise the possibility that IL-12 has a central role in driving macrophage polarization, regulating their intrinsic ability to respond against intracellular parasites. 相似文献
6.
Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer. 相似文献
7.
8.
BACKGROUND:
Flavonoids are polyphenolic substances with antioxidant properties, and they are found in different vegetables and fruits. Epidemiological studies have shown that the consumption of flavonoids reduces the prevalence of cardiovascular diseases. The use of synthetic antioxidants, however, has been limited because of their toxicity. Therefore, medical researchers have intensified their quest to find natural antioxidants.OBJECTIVES:
To investigate the effect of several pure flavonoids, such as kaempferol, quercetin, morin and rutin, on red blood cell hemolysis and evaluate their -SH capacity as an indicator of membrane protection.METHODS:
The rate of hemolysis and cell membrane -SH capacity were determined by spectrophotometry. Red blood cell peroxidation was induced using 2,2′-azo-bis-(2-amidinopropane) dihydrochloride. The effect of each flavonoid on hemolysis was examined at three concentrations (0.5 μg/mL, 5 μg/mL and 10 μg/mL), however, only the greatest concentration (10 μg/mL) of each flavonoid was used to study the effect on -SH groups.RESULTS:
In all cases, the antioxidant activity was dose-dependent. Rutin showed the highest inhibitory effect on hemolysis among flavonoids (42.5%). The protective effect of kaempferol, rutin and morin against -SH group oxidation measured 7.7%, 23.3% and 26.4%, respectively.CONCLUSIONS:
Results showed that flavonoids and flavonoid-containing plants can be used as natural antioxidants for the treatment and prevention of disease conditions, the pathogenesis of which is mediated by lipid peroxidation. 相似文献9.
Bauer K Hummel M Berek C Paar C Rosenberger C Kerzel S Versmold H Zemlin M 《Molecular immunology》2007,44(11):2969-2977
Homology-directed recombination, i.e. the preferential joining of gene segments at short sequence homologies, is found in 80% of IgH variable region genes from neonatal mice and causes a marked uniformity of their VH-DH- and DH-JH-junctions, which are predominated by one to three junctional sequences. To analyze the impact of homology-directed recombination on IgH gene diversity in humans, IgH rearrangements from fetuses and neonates (gestational age 20-42 weeks), infants (age 1-27 months) and adults were cloned and sequenced. As a marker of homology-directed recombination the VH-DH- and DH-JH-junctions were searched for nucleotides that could have been encoded by each of the two adjacent gene segments. Such overlapping sequences were rare (<3%) in VH-DH-junctions from newborns, infants, and adults. In contrast, overlapping sequences were found in 30% of the DH-JH-junctions from preterm neonates. Their frequency decreased with age to 19% in term neonates, 12% in infants and 4% in adults (p<0.001). Our analysis of the five most common DH-JH-combinations in neonates demonstrated that overlapping nucleotides reduced diversity: only 48% of junctions with overlapping nucleotides were different compared to 99% of junctions with N-insertions between DH and JH (p<0.001). However, homology-directed recombination had a much smaller effect on overall junctional diversity in human neonates than in neonatal mice because it rarely occurred in VH-DH-junctions and affected only 19% (term neonates) to 30% (preterm neonates) of the DH-JH-junctions. Therefore, unlike in mice, homology-directed recombination does not cause junctional uniformity in human neonates. 相似文献
10.
Haas DW Arathoon E Thompson MA de Jesus Pedro R Gallant JE Uip DE Currier J Noriega LM Lewi DS Uribe P Benetucci L Cahn P Paar D White AC Collier AC Ramirez-Ronda CH Harvey C Chung MO Mehrotra D Chodakewitz J Nguyen BY;Protocol / Study Teams 《AIDS (London, England)》2000,14(13):1973-1978
OBJECTIVES: To compare the efficacy and safety of two-times-daily versus three-times-daily indinavir in combination with zidovudine and lamivudine. DESIGN: Two multicenter, open-label, randomized 24-week studies. METHODS: Adults HIV-1 infection, HIV-1 RNA greater than 10000 copies/ml, and no prior lamivudine or protease inhibitor therapy were eligible. In a pilot study (Study A), patients received indinavir at 800 mg every 8 h, 1000 mg every 12 h, or 1200 mg every 12 h. In a subsequent study (Study B), patients received indinavir at 800 mg every 8 h or 1200 mg every 12 h. All subjects received zidovudine (300 mg) and lamivudine (150 mg) every 12 h. An intent-to-treat analysis was used. RESULTS: In Study A, which enrolled 88 patients, neither HIV-1 RNA nor CD4 cell responses differed significantly between treatment groups at 24 weeks when corrected for multiple comparisons. Study B enrolled 433 patients, but was prematurely discontinued when interim analysis suggested greater efficacy of three-times-daily indinavir. Of the first 87 patients reaching week 24, HIV-1 RNA was less than 400 copies/ml in 91% receiving three-times-daily versus 64% receiving two-times-daily indinavir (P < 0.01). CONCLUSION: Three-times-daily indinavir appears more efficacious than two-times-daily dosing when administered with zidovudine and lamivudine. Two-times-daily indinavir dosing should only be considered in situations characterized by favorable pharmacokinetic drug-drug interactions. 相似文献