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排序方式: 共有424条查询结果,搜索用时 15 毫秒
1.
T. Diemer D. Buchanan Hales T. Diemer M. Ludwig Petra Huwe W. Weidner 《Reproduktionsmedizin》2000,16(2):155-167
Urogenital infections are established as hazards to male fertility. Various pathophysiological hypotheses have evolved from experimental and clinical studies, facilitating explanation of the effects of bacteria and immunological events on reproductive tissues. Numerous current studies have identified and evaluated infectious mediators accounting for specific molecular events in urogenital infections. Valuable studies can be expected to appear in the future due to improvements in diagnostic procedures and new classifications of urogenital infections. 相似文献
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3.
Focal ischemia of the rat brain,with special reference to the influence of plasma glucose concentration 总被引:5,自引:0,他引:5
Summary Focal cerebral ischemia was induced by occlusion of the right middle cerebral artery in hypoglycemic, normoglycemic, as well as in acute and chronic diabetic rats. The brain damage was studied after 4 days. The volume of infarction was decreased in hypoglycemia (29±19 mm3 (mean±SD) versus 58±35 mm3,P<0.0046), unaltered in acute diabetes (61±45 mm3), and increased in chronic diabetes (91±22 mm3,P<0.0463). The cortex adjacent to the infarct showed selective neuronal injury affecting the cortical layers 2 and 3. The damage was enhanced by hypoglycemia and prevented in most of the diabetic animals. The findings indicate that different mechanisms cause infarction and selective neuronal injury outside infarcts, but that both are influenced by the plasma glucose concentration. 相似文献
4.
K Overgaard T Sereghy G Boysen H Pedersen S H?yer N H Diemer 《Journal of cerebral blood flow and metabolism》1992,12(3):484-490
The purpose of this study was the development of a model of embolic stroke with high reproducibility concerning infarct volume. In 37 male Sprague-Dawley rats, the internal carotid artery was embolized with in vitro preformed suspensions of autologous microemboli resembling arterial thrombi. With a method of continuous flow through the carotid arterial catheter, reflux of blood with uncontrolled clotting and embolization was avoided, thereby providing control animals free of ischemic damage. The embolized animals had arterial occlusions on angiograms immediately after embolization and no spontaneous recanalization on angiograms 2 h later. The cerebral blood flow measured by the intra-arterial 133Xe injection method decreased to 21-37% of baseline values. All embolized animals developed hemiparesis with spontaneous circling behavior, embolization with more than 150 microliters clot suspension resulted in hemispherical infarcts. There was a strong statistically significant correlation between amount of emboli, rate of vascular occlusion, and volume of infarcted tissue. This is the first model presented utilizing autologous in vitro microemboli imitating "white" arterial thrombi. The animals developed infarction, resembling human stroke. 相似文献
5.
Sotlar K Diemer D Dethleffs A Hack Y Stubner A Vollmer N Menton S Menton M Dietz K Wallwiener D Kandolf R Bültmann B 《Journal of clinical microbiology》2004,42(7):3176-3184
A nested multiplex PCR (NMPCR) assay that combines degenerate E6/E7 consensus primers and type-specific primers was evaluated for the detection and typing of human papillomavirus (HPV) genotypes 6/11, 16, 18, 31, 33, 35, 39, 42, 43, 44, 45, 51, 52, 56, 58, 59, 66, and 68 using HPV DNA-containing plasmids and cervical scrapes (n = 1,525). The performance of the NMPCR assay relative to that of conventional PCR with MY09-MY11 and GP5+-GP6+ primers, and nested PCR with these two primer sets (MY/GP) was evaluated in 495 cervical scrapes with corresponding histologic and cytologic findings. HPV prevalence rates determined with the NMPCR assay were 34.7% (102 of 294) in the absence of cervical intraepithelial neoplasia (CIN 0), 94.2% (113 of 120) in the presence of mild or moderate dysplasia (CIN I/II), and 97.8% (44 of 45) in the presence of severe dysplasia (CIN III). The combination of all four HPV detection methods applied in the study was taken as "gold standard": in all three morphological subgroups the NMPCR assay had significantly (P < 0.0001) higher sensitivities than the MY09-MY11 and GP5+-GP6+ assays and sensitivities comparable or equal to those of the MY/GP assay. All 18 HPV genotypes investigated were detected among the clinical samples. The ratio of high- to low-risk HPV genotypes increased from 4:1 (80 of 103) in CIN 0 to 19:1 (149 of 157) in CIN I to III. Multiple infections were detected in 47.9% (124 of 259) of the patients. In conclusion, the novel NMPCR method is a sensitive and useful tool for HPV DNA detection, especially when exact HPV genotyping and the identification of multiple HPV infections are required. 相似文献
6.
Normothermic rats with 12 min, complete cerebral ischemia were treated with the AMPA antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo (F) quinoxalinedione (NBQX) [10], which prevents CA1 pyramidal neuron loss. Twenty hours after ischemia, cerebral protein synthesis rate (CPSR) was measured autoradiographically using [35S]methionine. Ischemia caused a 38% decrease of CPSR in CA1, and postischemic treatment with NBQX caused a 66% decrease in this region. Also treatment with NBQX alone resulted in a decrease (22% in CA1) of the CPSR. Since some evidence exists that the neuroprotective effect of NBQX is related to blockade of the fast AMPA-mediated transmission, the further decrease of the postischemic CPSR in CA1 could be a mere side effect. 相似文献
7.
Calcium-imaging with Fura-2 in isolated cerebral microvessels 总被引:1,自引:0,他引:1
Cerebral microvessels were isolated from rat hippocampus with a modified, mild collagenase digestion and loaded with the calcium fluoroprobe, Fura-2. Using a fluorescence microscope with quartz optics and an image analyser, it was possible to measure the intracellular concentration of free calcium ions [Ca2+]i in single microvessels for the first time. A resting level of (90 +/- 28) nmol/l (+/- SD, n = 24) was calculated which immediately rose after ionomycin application. The temporal resolution for [Ca2+]i of our set-up was 0.7 s. By image processing, sequences of digitized fluorescence images of single microvessels were colour-coded in terms of [Ca2+]i with a spatial resolution up to 1.5 microns (pixel size). Both the temporal and spatial resolution make our system suitable for investigation of calcium-mobilizing receptors of the blood-brain barrier. 相似文献
8.
A Gjedde K Wienhard W D Heiss G Kloster N H Diemer K Herholz G Pawlik 《Journal of cerebral blood flow and metabolism》1985,5(2):163-178
The glucose metabolic rate of the human brain can be measured with labeled deoxyglucose, using positron emission tomography, provided certain conditions are fulfilled. The original method assumed irreversible trapping of deoxyglucose metabolites in brain during the experimental period, and it further requires that a conversion factor between deoxyglucose and glucose, the "lumped constant," be known for the brain regions of interest. We examined the assumption of irreversible trapping of fluorodeoxyglucose metabolites in brain of four patients in 365 normal and 4 recently infarcted regions. The average net, steady-state rate of fluorodeoxyglucose (KD) accumulation in normal regions of the four patients was 0.025 ml g-1 min-1. We also examined the variability of the lumped constant. We first confirmed that methylglucose is not phosphorylated in the human brain. We then estimated the lumped constant from the regional distribution of labeled methylglucose in brain. The average (virtual) volume of distribution of labeled methylglucose in the normal regions was 0.46 ml g-1 and was the same in both gray and white matter structures. The average brain glucose content corresponding to this value was 1.3 mumol g-1, assuming a Michaelis constant (Kt) of 3.7 mM for glucose transport across the blood-brain barrier. The lumped constant varied insignificantly between 0.4 and 0.5 in most regions, with an overall average of 0.44. It did not vary significantly between the patients and was the same in gray and white matter structures, but was inversely related to the calculated metabolic rate. This observation indicates that metabolic rates calculated with a fixed lumped constant (e.g., 0.40) would be slightly underestimated at high metabolic rates and slightly overestimated at low metabolic rates. The average glucose metabolic rates of the 365 normal regions, in which gray matter regions prevailed by 20:1, was 32 mumol 100 g-1 min-1. The average glucose phosphorylation rate in white matter was 20 mumol 100 g-1 min-1 with a lumped constant of 0.45. In the recently infarcted areas, the lumped constants varied from 0.37 to 2.83, corresponding to glucose metabolic rates varying from 2 to 18 mumol 100 g-1 min-1. Two infarct types were identified. In one type, the phosphorylation-limited type, glucose content and the lumped constant were close to normal (1 mumol g-1 and 0.40, respectively). In the other, the transport/flow-limited type, the glucose content was low (0.2 mumol g-1), and the lumped constant in excess of unity. The evidence from the present study upholds the model of Sokoloff et al. in every detail. 相似文献
9.
Bone scan in the patellofemoral pain syndrome 总被引:3,自引:0,他引:3
Summary Eighty patients who complained of retropatellar pain underwent evaluation by bone scintigraphy, intraosseous pressure determination, radiography, arthroscopy and physical diagnostic tests. The bone scans showed that 48% of the painful knees had an increased uptake compared with 9% for the normal joints. A highly significant correlation was evident between an increased uptake and established chondromalacia. For the diagnosis of a high pressure patella, radiography was only 7% sensitive (6/88), compared with 44% (39/88) for bone scintigraphy and 78% for the clinical sustained flexion test. The positive predictive value of a bone scan for detecting a high pressure patella was 0.72 (39/54). The best predictor was a positive sustained flexion test with a predictive value of 0.85 (69/81).
Résumé Dix-huit malades se plaignant de douleurs rétro-patellaires ont été examinés par scintigraphie, mesure de la pression intra-osseuse, radiographie, arthroscopie et tests cliniques. La scintigraphie a montré que 48% des genoux douloureux présentaient une hyperfixation contre 9% des articulations normales. Il existait une corrélation évidente, hautement significative, entre l'hyperfixation et la chondropathie rotulienne. Pour le diagnostic d'hyperpression intrapatellaire, la radiographie n'était démonstrative que dans 7% des cas (6/88) alors que la scintigraphie l'était dans 44% (30/88) et le test clinique de «flexion prolongée» dans 78%. La valeur d'une scintigraphie positive en faveur du diagnostic d'hyperpression intra-patellaire est de 0.72 (39/54). L'élément le plus fiable est la positivité du test de flexion prolongée qui a une valeur prédictive de 0.85 (69/81).相似文献
10.