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Since the introduction of Tc-99m labeled radiopharmaceuticals, flow studies have become a useful and readily performed component of renal nuclear medicine examinations. In addition to detecting aberrations of renal perfusion, a number of extrarenal abnormalities may also be surreptitiously detected. Three cases of hyperperfused skeleton, an extremely unusual finding which complements two previous reports in the literature, have recently been observed. All three of the patients, as well as the two previously described, had underlying neoplastic abnormalities. The appearance of perfused skeleton should therefore be recognized as suggesting the presence of underlying neoplastic disease. Considerable interest as to the etiology and magnitude of the increased skeletal perfusion exists. Measurements of normal marrow and osseous perfusion have been reviewed in order to better appreciate the magnitude of increase required for skeletal visualization on renal flow studies. Some considerations as to the etiology of this increase are offered.  相似文献   
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The objective of this study was to examine the combined electromyographic (EMG) and mechanical response to a rearward perturbation and to separate the response into three categories: preset properties of the muscle, reflex changes to the muscle, and active changes to the muscle. We hypothesized that an active response is required to maintain balance on a moving platform. Eleven healthy adult subjects stood on a platform oscillating at three frequencies (0.75, 1.0, and 1.25 Hz). Ankle extensor EMG activity and ankle moment were analyzed and compared for initial movement cycles. Timing of events in EMG and moment data were examined to separate observed changes into the three categories. Results showed an initial rise in ankle moment as the platform started to move backwards, followed by a more rapid reflex increase. After a slight drop, ankle moment again rose due to active response. By the third cycle of platform movement, the EMG and moment were synchronized with the platform movement, maintaining the body in a desired posture. Initial preset properties of the ankle extensor muscles combined with reflex activity were not sufficient to maintain balance. Following an initial reflex reaction, further active control was required to match the timing of the ankle moment and the platform motion and avoid a loss of balance. This study provides new insight for the rehabilitation of postural deficits.  相似文献   
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Alopecia areata (AA) is a type of non-scarring, recurrent patchy loss of hair in hair-bearing areas and is mostly of autoimmune origin. Previous studies have suggested that some autoimmune diseases were found to be associated with vitamin D deficiency. The current study was designed to assess the levels of serum 25-hydroxy vitamin D and C-reactive protein in AA, as compared with controls and to further identify the association between vitamin D levels and disease severity in patients with AA. This cross-sectional study included 45 patients with AA and 45 healthy volunteers. Clinical and anthropometric parameters were recorded, according to a pre-designed proforma. Serum 25-hydroxy vitamin D and high-sensitivity C-reactive protein were estimated using ELISA kits. The severity of AA was determined using Severity of Alopecia Tool (SALT) score. We observed a significant rise in systemic inflammation as seen by elevated high-sensitive C-reactive protein levels and lowered 25-hydroxy vitamin D levels in patients with alopecia areata, compared to controls (p?=?0.001). The levels of 25-hydroxy vitamin D showed a significant negative correlation with disease severity, while hs-CRP levels showed a significant positive correlation with disease severity (ρ?=???0.714, p?=?0.001 and ρ?=?0.818, p?=?0.001). Our results suggest significant systemic inflammation and vitamin D deficiency in alopecia areata, more so with increasing disease severity. This gains particular importance in the treatment of alopecia areata in future, as supplementing vitamin D to AA patients would result in reducing the disease severity and inducing remission.  相似文献   
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Atorvastatin is a selective HMG-CoA reductase competitive inhibitor, used for the treatment of hyperlipidaemia. It is metabolized by CYP 3A4 and 3A5 isoenzymes in liver. It also has moderate inhibition on metabolizing enzymes like CYP 2C9, 2D6 and 3A4. Hence there is more possibility of atorvastatin for inhibition of metabolism of glyburide, by both CYP 2C9 and 3A4. We have studied the effects of atorvastatin on the pharmacodynamics and pharmacokinetics of glyburide in experimental diabetic rats. Atorvastatin (20 mg/kg p.o.) was given to alloxan-induced diabetic rats for 7 consecutive days followed by glyburide (10 mg/kg p.o.). In the rats co-treated with atorvastatin and glyburide, fasting plasma glucose concentration (60.69 ± 5.70%) was further reduced, markedly as compared with glyburide-treated animals. In co-treated group, the pharmacokinetic parameters like clearance (27.83 ± 3.55 l/h) of glyburide was reduced, while peak plasma concentration (18.39 ± 5.29 μg/ml), area under the plasma concentration time curve (120.02 ± 15.17 μg/ml/h) and elimination half-life (4.09 ± 0.50 h) were significantly increased when compared to glyburide alone administered rats. The results of this study revealed that atorvastatin led to the PK/PD changes have been due to glyburide increased bioavailability, decrease volume of distribution, and/or decrease total clearance may be due to the inhibition of cytochrome P450 metobolic system.  相似文献   
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Silver nanoparticles (Ag-NPs) are known to have inhibitory and bactericidal effects. Resistance of fungal infections has emerged in recent years and is a major health problem. Here, we report the extracellular biosynthesis of Ag-NPs using a common fungus, Alternaria alternata. Also in this study, these nanoparticles were evaluated for their part in increasing the antifungal activity of fluconazole against Phoma glomerata, Phoma herbarum, Fusarium semitectum, Trichoderma sp., and Candida albicans. The antifungal activity of fluconazole was enhanced against the test fungi in the presence of Ag-NPs. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, which was confirmed from the increase in fold area of inhibition, followed by P. glomerata and Trichoderma sp., which showed less increase in the fold area, whereas no significant enhancement of activity was found against P. herbarum and F. semitectum.From the Clinical EditorThe antifungal activity of fluconazole was enhanced in presence of silver nanoparticles against the test fungi. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, followed by P. glomerata and Trichoderma sp. No significant enhancement of activity was found against P. herbarum and F. semitectum.  相似文献   
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OBJECTIVE: To examine effect of omentum transposition surgery (OT) in Alzheimer's disease (AD). METHODS: Within-subjects design, also known as repeated-measures design, was used. OT was performed on six biopsy-confirmed AD patients (three to the left and right hemispheres each). Follow-up was conducted over 16-50 months. Outcome measures included the sum of the sub-scores of the clinical dementia rating scale (CDRSS), dementia severity rating scale (DSRS), mini-mental status exam (MMSE) and neuropsychiatric inventory (NPI), all normalized to 0-1.0. Outcomes were compared to baseline values and to expected decline with and without cholinesterase inhibitors therapy (ChEI). RESULTS: Compared to baseline and to expected decline with ChEI, CDRSS scores were 22 and 39% less impaired at means of 14 and 25 months post-OT, and DSRS scores were 12 and 22% less impaired at means of 14 and 19 months post-OT (p<0.0001). Compared to baseline and expected course with and without ChEI, the MMSE scores of the left hemisphere OT patients were not significantly different for 11, 17 and 22 months respectively (p>0.49), while those of the right hemisphere OT patients more rapidly declined. The two patients with significant pre-operative behavioral problems markedly improved; NPI severity scores decreased by 23 (16%) and 78 (54%) points and were sustained for 22 and 42 months. DISCUSSION: OT yielded cognitive, functional or behavioral improvement for up to 3.5 years in these AD patients. Compared to randomized ChEI clinical trials, OT was 34 times more likely to produce clinically significant improvement. Basic research to identify the mechanisms underlying the therapeutic effect of omentum is warranted.  相似文献   
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