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61.
The aim of this work was to determine the protective effects of intraperitoneally administered vitamins C and E and selenium
on the lipid peroxidation (MDA), glutathione peroxidase (GSH-Px), reduced glutathione (rGSH) activities in the lens of rats
induced diabetic with streptozotocin (STZ). Lenses in the diabetic control group had a slightly higher mean level of MDA compared
with lenses of the vitamin E and selenium groups, although the mean levels of MDA were significantly lower in control, combination,
and vitamin C groups than in the diabetic control group (p < 0.05 andp < 0.01). However, MDA levels were significantly lower in vitamin C, vitamin E, and combination groups than in controls (p < 0.01).
The GSH-Px activities of lenses were significantly higher in vitamin C-, vitamin E- and selenium-injected groups than that
in the diabetic control group (p < 0.01), whereas, the activity of GSH-Px was significantly lower in the diabetic control group than in the control group.
In addition, the rGSH content was seen to decrease only in the vitamin C group compared to both control and diabetic control
groups (p < 0.05).
In conclusion, the results from these experiments indicate that vitamins C and E and selenium can protect the lens against
oxidative damage, but the effect of vitamin C appears to be much greater than that of vitamin E and selenium. 相似文献
62.
Na Sun Noriko Tamura Tomohiro Tamura Roland Wilhelm Knispel Thomas Hrabe Christine Kofler Stephan Nickell István Nagy 《Proteomics》2009,9(14):3783-3786
We used molecular sieve chromatography in combination with LC‐MS/MS to identify protein complexes that can serve as templates in the template matching procedures of visual proteomics approaches. By this method the sample complexity was lowered sufficiently to identify 464 proteins and – on the basis of size distribution and bioinformatics analysis – 189 of them could be assigned as subunits of macromolecular complexes over the size of 300 kDa. From these we purified six stable complexes of Thermoplasma acidophilum whose size and subunit composition – analyzed by electron microscopy and MALDI‐TOF‐MS, respectively – verified the accuracy of our method. 相似文献
63.
Aycan Bilisik Ayse Yenigun Adem Bicakci Kayi Eliacik Yakup Canitez Hulusi Malyer Nihat Sapan 《Aerobiologia》2008,24(1):61-66
Pollen grains in the atmosphere of Didim, collected using a Durham sampler, were investigated in 2004 and 2005. Weekly pollen
grains per square centimetre were calculated. Over a period of 2 years, 17,518 pollen grains/cm2 belonging to 40 taxa and unidentified pollen grains were recorded. In 2004, 9,879 pollen grains were counted per cm2, and in 2005 the value was 7,639 per cm2. The majority of pollen grains investigated were Pinus spp. (45.58%), Cupressaceae/Taxaceae (13.49%), Olea spp. (9.19%), Platanus spp. (7.62%), Gramineae (6.33%), Pistacia spp. (4.34%), Morus spp. (3.81%), Quercus spp. (2.02%), Abies spp. (1.39%), and Plantago spp. (1.11%). During the month of April, 40.46% of total pollen grains were recorded. According to our results, pollen season
durations for the dominated pollen grains in Didim were: the 7th–33rd weeks for Pinus spp., nearly the whole year except summer for Cupressaceae/Taxaceae, the 17th–29th weeks for Olea spp., the 10th–24th weeks for Platanus spp., the 8th–46th weeks for Gramineae, the 8th–20th weeks for Pistacia spp., the 11th–21st weeks for Morus spp., the 17th–21st weeks for Quercus spp., the 9th–27th weeks for Abies spp., and the 7th–26th weeks for Plantago spp. 相似文献
64.
The serum levels of copper, zinc, iron, manganese, nickel, cadmium, cobalt, sodium, potassium, calcium, and magnesium were
determined in seven different breeds of dogs: Pointer, Poodle, Setter, Labrador Retriever, Golden Retriever, German Shepherd,
and Mallinois. Only slight variations were found among the different breeds, and the results presented in this study can be
used for laboratory studies in veterinary science. 相似文献
65.
Zeynep Cantürk Nuh Zafer Cantürk Berrin etinarslan Nihat Zafer Utkan Ilhan Tarkun 《Obesity (Silver Spring, Md.)》2003,11(6):769-775
Objective: There is an increased morbidity and mortality associated with surgery in the obese patient. This study was conducted to determine risk factors and compare the nosocomial infection rate in obese and nonobese surgical patients. Research Methods and Procedures: A total of 395 surgical patients were evaluated. BMI was calculated for each patient. Various conventional risk factors for nosocomial infections were recorded. Biochemical parameters with plasma total cholesterol and high‐density lipoprotein‐cholesterol levels were measured. The diagnosis of infection was made according to the Centers for Disease Control and Prevention criteria. Univariate and two‐step multivariate logistic regression methods were used for determination of nosocomial infection risk factors. Results: There were 117 nosocomial infections identified in 96 of 395 surgically operated patients. A significant increase in the total number of nosocomial infections was determined in obese patients compared with the normal‐weight patients (p < 0.05). High‐density lipoprotein‐cholesterol below the 10th percentile increased risk of surgical site infection. Discussion: Our results suggest that obesity is an important risk factor for postoperative nosocomial infection. 相似文献
66.
Macroinvertebrate community structure in relation to environmental variables in a Swiss glacial stream 总被引:5,自引:0,他引:5
Brigitte Lods-Crozet Emmanuel Castella Diana Cambin Christiane Ilg Sandra Knispel & Helene Mayor-Simeant 《Freshwater Biology》2001,46(12):1641-1661
1. Benthic macroinvertebrate distribution was examined in relation to channel characteristics (including stability), substratum, hydraulic variables, primary production (chlorophyll a ) and coarse particular organic matter (CPOM) in an alpine glacial stream, the Mutt (Upper Rhône valley, Switzerland). Co-inertia analysis and canonical correspondence analysis were used to identify the major environmental gradients influencing community variations.
2. The Mutt (length: 3.6 km, altitudinal range: 1800–3099 m a.s.l.) exhibited typical characteristics of a kryal stream. Average summer temperature remained below 2 °C immediately downstream from the snout but was on average 5 °C higher 1700 m downstream. Seasonal variations in water sources were evidenced by the high late-summer (September) contribution of groundwater with increased conductivity.
3. Sixty-six taxa were recorded from the five reaches sampled at three periods (snowmelt, ice melt and low water in late summer) in 1996 and 1997, of which 29 were Chironomidae. Three taxa of Diamesinae were the first colonizers of the stream below the glacier, but 16 taxa, including Ephemeroptera, Plecoptera and Trichoptera, were already recorded 200 m downstream. Water depth, channel slope and Pfankuch's Index of channel stability were strongly correlated with the longitudinal faunal gradient. Maximum temperature, current velocity and water conductivity were also correlated, but to a lesser extent.
4. The rapid incorporation of non-chironomid taxa into the stream community represented a departure from Milner & Petts's (1994) conceptual model of invertebrate succession downstream of glacial margins. The results confirmed that glacial stream communities are primarily driven by physical determinants. 相似文献
2. The Mutt (length: 3.6 km, altitudinal range: 1800–3099 m a.s.l.) exhibited typical characteristics of a kryal stream. Average summer temperature remained below 2 °C immediately downstream from the snout but was on average 5 °C higher 1700 m downstream. Seasonal variations in water sources were evidenced by the high late-summer (September) contribution of groundwater with increased conductivity.
3. Sixty-six taxa were recorded from the five reaches sampled at three periods (snowmelt, ice melt and low water in late summer) in 1996 and 1997, of which 29 were Chironomidae. Three taxa of Diamesinae were the first colonizers of the stream below the glacier, but 16 taxa, including Ephemeroptera, Plecoptera and Trichoptera, were already recorded 200 m downstream. Water depth, channel slope and Pfankuch's Index of channel stability were strongly correlated with the longitudinal faunal gradient. Maximum temperature, current velocity and water conductivity were also correlated, but to a lesser extent.
4. The rapid incorporation of non-chironomid taxa into the stream community represented a departure from Milner & Petts's (1994) conceptual model of invertebrate succession downstream of glacial margins. The results confirmed that glacial stream communities are primarily driven by physical determinants. 相似文献
67.
Summary The observation of various types of spatio-temporal correlations in spike-patterns of multiple cortical neurons has shifted
attention from rate coding paradigms to computational processes based on the precise timing of spikes in neuronal ensembles.
In the present work we develop the notion of “spatial” and “temporal interaction” which provides measures for statistical
dependences in coupled stochastic processes like multiple unit spike trains. We show that the classical Willshaw network and
Abeles’ synfire chain model both reveal a moderate spatial interaction, but only the synfire chain model reveals a positive
temporal interaction, too. Systems that maximize temporal interaction are shown to be almost deterministic globally, but posses
almost unpredictable firing behavior on the single unit level. 相似文献
68.
Serum sialic acid levels and selected mineral status in patients with type 2 diabetes mellitus 总被引:2,自引:0,他引:2
The aim of the present study was to investigate whether altered serum total sialic acid (TSA), lipid-associated sialic acid
(LSA), copper (Cu), manganese (Mn), zinc (Zn), chromium (Cr), iron (Fe), and magnesium (Mg) levels had an interactive connection
with diabetes and also whether they were correlated with each other in diabetic patients. Two study groups (control and type
2 diabetic subjects) were included. Two hundred patients (108 female and 92 male), diagnosed and treated for type 2 diabetes
in the Yuzuncu Yil University Hospital (Van, Turkey), were selected consecutively to represent type 2 diabetic patients. Fifty
healthy individuals (29 female and 21 male) served as the control group matched for age, sex, body mass index, and smoking
status were selected from hospital staff and other outpatient clinics. All participants had not taken vitamin or mineral supplements
for at least 2 wk before sampling. Blood samples were drawn after an overnight fasting in both groups for the determination
of serum glucose, TSA, LSA, Cu, Zn, Mn, Cr, Fe, and Mg. It was found that diabetics had higher TSA, LSA, Fe, Mn, Fe/Zn, and
Cu/Zn levels, and lower Zn and Mg levels than those of controls. Although, Cu levels were higher, and Cr levels were lower
in total and male diabetic patients, they were not different in female diabetic patients than in controls. The Cu/Fe ratio
was lower in total and female diabetic patients, but not different in male diabetic patients than controls. The Zn/Cr ratio,
on the other hand, was not different in diabetics than in controls. There was only a positive correlation between Fe-Mn levels
in male diabetic patients. There was a negative correlation in LSA-Mn, Fe-Cu, Cu-Fe/Zn, and Mn-Cu/Zn levels in total diabetic
patients. There was a positive correlation in TSA-Cr, TSA-Mg, LSA-Cu/Fe, LSA-Zn/Cr levels, and a negative correlation in TSA-Cu/Zn,
LSA-Mn, Fe-Cu, Mn-Cu, Cu-Fe/Zn, Fe-cholesterol, and Cr-cholesterol in female diabetic patients. Our results showed that TSA,
LSA, and selected minerals have interactive connections with diabetes mellitus (DM). There are also many sex-related positive
or negative correlations between the altered parameters in diabetic patients. These parameters might be used as diagnostic
index in patients with DM. 相似文献
69.
We report a simple and generic method for the direct transfer of protein complexes separated by native gel electrophoresis to electron microscopy grids. After transfer, sufficient material remains in the gel for identification and characterization by mass spectrometry. The method should facilitate higher-throughput single-particle analysis by substantially reducing the time needed for protein purification, as demonstrated for three complexes from Thermoplasma acidophilum. 相似文献
70.
Wanfen Xiong Rebecca Knispel Jason MacTaggart Timothy C. Greiner Stephen J. Weiss B. Timothy Baxter 《The Journal of biological chemistry》2009,284(3):1765-1771
During arterial aneurysm formation, levels of the membrane-anchored matrix
metalloproteinase, MT1-MMP, are elevated dramatically. Although MT1-MMP is
expressed predominately by infiltrating macrophages, the roles played by the
proteinase in abdominal aortic aneurysm (AAA) formation in vivo
remain undefined. Using a newly developed chimeric mouse model of AAA, we now
demonstrate that macrophage-derived MT1-MMP plays a dominant role in disease
progression. In wild-type mice transplanted with MT1-MMP-null marrow, aneurysm
formation induced by the application of CaCl2 to the aortic surface
was almost completely ablated. Macrophage infiltration into the aortic media
was unaffected by MT1-MMP deletion, and AAA formation could be reconstituted
when MT1-MMP+/+ macrophages, but not MT1-MMP+/+
lymphocytes, were infused into MT1-MMP-null marrow recipients. In
vitro studies using macrophages isolated from either
WT/MT1-MMP-/- chimeric mice, MMP-2-null mice, or MMP-9-null mice
demonstrate that MT1-MMP alone plays a dominant role in macrophage-mediated
elastolysis. These studies demonstrate that destruction of the elastin fiber
network during AAA formation is dependent on macrophage-derived MT1-MMP, which
unexpectedly serves as a direct-acting regulator of macrophage proteolytic
activity.Development and progression of abdominal aortic aneurysm
(AAA)2 is a complex
process that, untreated, can lead to tissue failure, hemorrhage, and death
(1). Destruction of the orderly
elastin lamellae of the vessel wall is considered the sine qui non of arterial
aneurysm formation (2) as adult
tissues cannot regenerate normal elastin fibers
(3). Moreover, the elastin
degradation products are chemotactic for inflammatory cells and serve to
amplify the local injury (4).
Although several types of elastolytic proteases are elevated in AAA tissue
(5-9),
studies using murine models of AAA and targeted protease deletion suggest that
matrix metalloproteinases (MMPs), particularly the secreted proteases, MMP-2
and MMP-9, play key roles in the pathologic remodeling of the elastin lamellae
that lead to AAA (7,
8).Membrane-type 1 MMP (MT1-MMP) is the prototypical member of a family of
membrane-tethered MMPs (10).
Recent studies indicate that MT1-MMP expression is elevated in human AAA
tissues and that infiltrating macrophages are the primary source of the
proteinase in aortic lesions
(11-13).
Although indirect evidence suggests that MT1-MMP may participate in the
control of monocyte/macrophage motile responses as well as interactions with
the vessel wall during transmigration
(14,
15), the role(s) played by
MT1-MMP in regulating macrophage proteolytic activity or AAA formation in
vivo remains undefined.Using a murine model of AAA and mice with a targeted deletion of MT1-MMP in
myelogenous cell populations, we now demonstrate that macrophage-derived
MT1-MMP is required for elastin degradation and aneurysm formation.
Importantly, macrophages are not dependent on MT1-MMP for infiltrating aortic
tissues but instead use the protease to directly regulate their elastolytic
potential in an MMP-2- and MMP-9-independent fashion. These studies define a
new and unexpected role for MT1-MMP in controlling macrophage elastolytic
activity in the in vitro and in vivo settings. 相似文献