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91.
92.
目的 :探讨黄色肉芽肿性肾盂肾炎 (XGP)的诊治方法。方法 :分析了 8例XGP的临床资料 ,并就其临床表现、诊断及治疗进行分析讨论。结果 :7例术前误诊或漏诊 ,1例术前诊为XGP ;7例呈弥漫型XGP患者行患肾全切 ,1例呈局限型XGP行肿块剜除术 ,术后疗效好 ,未见复发。结论 :对于有长期尿路感染史以及X线发现某些可疑性改变者 ,CT、DSA以及B超有助于正确诊断。尿沉淀找泡沫细胞和B超引导下细针穿刺活检可以明确诊断。治疗上对弥漫型病变主张肾全切除术 ,局限型主张行肾部分切除或肿块剜除术。 相似文献
93.
Demont RG Lephart SM Giraldo JL Giannantonio FP Yuktanandana P Fu FH 《The Journal of sports medicine and physical fitness》1999,39(3):253-258
BACKGROUND: The purpose of this study was to compare the training effects of the Ab-Flex (F), Ab-Roller (R) and standard crunch (C) on EMG production, isometric maximum voluntary contraction (MVC), and isokinetic average peak torque at 30 degrees/sec (ISO) of the abdominal muscles. It was hypothesized that the training devices would have similar value in a strength training program. METHODS: Experimental design: this was a prospective study involving 18 training sessions of progressively increasing repetitions. Setting: Neuromuscular Research Laboratory, University of Pittsburgh. Subjects: thirty-two subjects volunteered for this study, but only 26 completed the training. Each subject participated in recreational activity, but had not performed any abdominal training prior to starting this study. Each subject was randomly assigned to either the control group or one of the treatment groups. Interventions: there were three interventions: two training devices (Ab-Flex and Ab-Roller) and the standard crunch, considered a control group. Measures: the pretest consisted of skin fold measurements (%), EMG activity (V) during the three interventions, and peak torque (Nm) plus EMG during the MVC and ISO tasks. The 18 training sessions over three weeks consisted of three sets of exercise with increasing repetitions from 10 to 20, by 2, every three sessions. The difference in pretest/posttest scores were compared using a One-way ANOVA on the mean differences (Mdiff) for each of: MVC, ISO (peak torque), and EMG for upper rectus (UR), lower rectus (LR), internal oblique (IO), and external oblique (EO). A T-Test was used to detect significance for the body fat measures. RESULTS: Mean differences (Mdiff) were normally distributed about zero for both MVC and ISO (MVC = -0.55, ISO = 4.57). The analysis by group showed no difference (p = 0.596) on the reported means (Nm) -3.16 (C), 5.84 (F) and -4.83 (R). The change associated to the treatment during MVC was only 4% (eta = 0.04). For the ISO the Mdiff (Nm) were 1.39 (C), 13.66 (F) and -2.06 (R) which were not significant (p = 0.127). The Ab-Flex was the only group to have a 95% confidence interval above zero, increasing by an average of 16.5%. There were no significant differences for the EMG activity for Mdiff or between group scores. CONCLUSIONS: No significant differences were found with this study. These results would suggest that using these devices does not add significantly to overall abdominal strength development, or reduction of body fat. A suggestion could be made that certain devices influence muscles differently. 相似文献
94.
Lavi E Schwartz T Jin YP Fu L 《Journal of neuropathology and experimental neurology》1999,58(12):1197-1206
The presence of terminally differentiated slow- and non-dividing cells in the central nervous system (CNS) provides a safe harbor for viral persistence and latency and constitutes a unique immunologic environment for viral infections. Studies of experimental model systems of viral infections of the CNS provide insight into mechanisms of viral persistence and immune-mediated pathology. Nidoviruses are comprised of 2 families of viruses, coronaviruses and arteriviruses, and are common pathogens of humans and a variety of animal species. Both families of viruses contain neurotropic strains that produce experimental neurologic diseases in rodents. These include acute meningitis and encephalitis; acute poliomyelitis; and chronic inflammatory, immune-mediated, demyelination. Coronavirus-induced demyelinating disease mimics many of the pathologic features of Multiple Sclerosis (MS). 相似文献
95.
Hoppensteadt DA Jeske WP Walenga JM Fu K Yang LH Ing TS Herbert JM Fareed J 《Thrombosis research》1999,96(2):115-124
Varying dosages of pentasaccharide (400-800 nmol/kg) were compared to a 250-U/kg single bolus dosage of unfractionated heparin (UFH) in a dog model of hemodialysis. Several laboratory assays were used to monitor the effects of pentasaccharide and UFH. The pentasaccharide did not produce any anticoagulant effects as measured by the activated partial thromboplastin time. However, in the anti-Xa chromogenic assay and the Heptest assays, there was a dose-dependent prolongation after pentasaccharide administration. In the group of dogs administered 800 nmol/kg of pentasaccharide, there was a 50% decrease in the thrombin antithrombin (TAT) complex level after 60 minutes on dialysis. In the UFH-treated dogs, wide variations in assays were observed. There was a marked elevation in the activated partial thromboplastin time and Heptest assays up to 6 hours after UFH administration. Both anti-Xa and anti-IIa activity was measured up to 4 hours. In the TAT assay, UFH was found to have a stronger effect in suppressing the formation of TAT in comparison to the pentasaccharide. These results suggest that pentasaccharide can be used as a replacement for UFH in a dog model of hemodialysis to keep the dialysis circuit patent. In addition, the anti-Xa-based assays such as the Heptest and the chromogenic anti-Xa assays can be used to monitor the effects of pentasaccharide in this model. 相似文献
96.
97.
Determination of the concentration of osteocalcin in rat serum is frequently performed using a commercially available radioimmunoassay
(RIA). However, this assay takes 3 days to complete, uses radioactive material, and has a narrow linear range. The limited
range of the RIA makes it necessary to test multiple dilutions of the sample which frequently results in values that differ,
depending on the dilution. In order to overcome these limitations, we have developed an ELISA that utilizes the same standards
and anti-rat osteocalcin antiserum, as is used in the RIA. The principle of the ELISA is that the osteocalcin in the sample
competes with osteocalcin previously immobilized on a microtiter plate to bind to the available anti-rat osteocalcin antibodies.
The amount of antibody bound to the immobilized osteocalcin is determined colorimetrically using a secondary antibody coupled
to alkaline phosphatase. This ELISA has a three-log linear response with a sensitivity of 0.1–0.15 ng/ml and intra- and interassay
coefficient of variance (CV) values of less than 10%. Most importantly, the assay is rapid and only requires a 2-hour incubation
of the sample with the antiserum. The incubation time is important since we and others have observed a significant decrease
in the osteocalcin level from serum samples incubated for long periods of time with the antiserum, presumably due to degradation
of the osteocalcin. In general, the commercially available RIA gives osteocalcin values that are one-half to one-fourth that
of the ELISA because the RIA requires a 48-hour incubation time.
Received: 14 November 1997 / Accepted: 9 July 1998 相似文献
98.
99.
1-N HAPA gentamicin B, a new aminoglycoside active against gentamicin resistant isolates--activity compared to other aminoglycosides. 总被引:1,自引:0,他引:1
1-N HAPA gentamicin B is a new aminoglycoside active against most Enterobacteriaceae, Pseudomonas aeruginosa and Staphylococcus aureus. Among 504 clinical isolates at a concentration of 12.5 microgram/ml all Staph. aureus, Escherichia coli, Klebsiella, Enterobacter, Proteus rettgeri, Providencia and 78% of Pseudomonas, 86% of Proteus morganii were inhibited. Like other aminoglycosides, the activity was greatest at an alkaline ph and reduced by high cations concentrations. 1-N HAPA gentamicin B was equal in activity to amikacin against both gentamicin-sensitive and resistant isolates. It inhibited bacteria containing many of the aminoglycoside inactivating enzymes. When combined with carbenicillin it inhibited in a synergistic manner many Gram-negative bacteria, particularly Pseudomonas and Serratia. 相似文献
100.
Cyclopenta-polycyclic aromatic hydrocarbons (cyclopenta-PAHs) are a group of compounds that have been detected as environmental pollutants. Perturbation molecular orbital (PMO) calculations on their presumed ultimate carcinogenic metabolites, the cyclopenta-PAH expoxides, predict that they may have a greater biological hazard than the classic PAHs. 相似文献