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61.
Breakwell LM  Getty CJ  Dobson P 《The Knee》2000,7(3):145-147
A controlled, randomised, prospective study was undertaken to assess the efficacy of the use of a blood re-infusion device in the reduction of allogenic blood requirements of patients undergoing bilateral simultaneous total knee replacements. Thirty-three consecutive patients were randomised to receive allogenic blood only, or a combination of collected and re-infused blood. An average of 1000 ml of drainage blood was salvaged in the study group, resulting in a significant reduction in allogenic blood requirements from 6.3 to 3.8 units in total (P value=0.002). No patients suffered transfusion reactions. We conclude that autologous re-infusion is a safe and effective method of reducing allogenic blood requirements, and as a result, reducing the risks of transmission of infection, and the rate of post-operative infection.  相似文献   
62.
We report the MRI appearances in a patient with parametrial malakoplakia. The patient complained of pelvic pain and vaginal discharge. Physical examination revealed a "frozen" pelvis suggestive of malignancy. MRI showed bilateral parametrial "infiltration", but no overt primary pelvic tumour. The combination of these findings together with the inflammatory symptoms suggested an inflammatory condition. Malakoplakia was confirmed at resective biopsy.  相似文献   
63.
Antinuclear antibody and in vivo capillary patterns were studied in 33 patients with Raynaud's phenomenon only and in 68 patients with scleroderma spectrum disorders; the results were correlated with clinical and laboratory findings. In addition, antinuclear antibody results in the groups with Raynaud's phenomenon only and scleroderma spectrum disorders were compared with those found in 70 patients with systemic lupus erythematosus (SLE). Distinct antinuclear antibody profiles were observed in the three diagnostic groups. Comparison of patients with anticentromere antibodies with others in the group with scleroderma spectrum disorders demonstrated that anticentromere antibody-positive patients tended to have a milder disease: less skin and visceral involvement, less frequent presence of hypertension, anemia, and elevated sedimentation rate. These differences did not, however, reach statistical significance. Comparison of patients with scleroderma spectrum disorders according to in vivo capillary patterns revealed that those with an "active" pattern had significantly more extensive skin involvement than those with a "slow" pattern. Visceral involvement tended to be greater in all organ systems in the group with an "active" pattern and reached statistical significance for muscle and kidney. Hypertension was also significantly more frequent in the group with an "active" pattern than in the group with a "slow" one. The latter was positively correlated with the presence of anticentromere antibody.  相似文献   
64.
Exercise treadmill tests and ambulatory monitoring were used in a double-blind, placebo-controlled, double-dummy crossover comparison of nifedipine (10 mg, 3 times daily) and transdermal nitroglycerin (15 mg). All patients (n = 20) had chronic stable angina with symptomatic and silent events. All patients had 3 episodes of angina/week and 3 episodes of ischemia/24 hr. The protocol was made up of 2 weeks of placebo followed by 2 weeks of active drug, then crossed over for 2 weeks of placebo followed by the other active drug. At the end of each 2-week period, patients had ambulatory monitoring and exercise treadmill testing. All ambulatory monitoring reports were read blind and entered into an independent data base. The results were the following: on transdermal nitroglycerin, the duration of ischemia decreased by 57% from 140 min/24 hr to 60 min/24 hr (p = 0.0054). The exercise time increased by 5.5% from 4.8 to 5.0 minutes (p = 0.16). With nifedipine, the duration of ischemia decreased by 22% from 175 min/24 hr to 137 min/24 hr (p = 0.16). The exercise tolerance time increased by 13% from 4.5 to 5.0 minutes (p = 0.0264). Nifedipine increased exercise time without altering total ischemic time, while transdermal nitroglycerin decreased total ischemic time without increasing exercise time. Thus, changes in exercise time do not necessarily predict changes in total ischemic time.  相似文献   
65.
66.

Introduction

Cadaveric cutaneous allografts are used in burns surgery both as a temporary bio-dressing and occasionally as definitive management of partial thickness burns. Nonetheless, limitations in the understanding of the biology of these grafts have meant that their role in burns surgery continues to be controversial.

Methods

A review of all patients suffering 20% or greater total body surface area (TBSA) burns over an eight year period that received cadaveric allografts were identified. To investigate whether tissue viability plays a role in engraftment success, five samples of cryopreserved cadaveric cutaneous allograft processed at the Donor Tissue Bank of Victoria (DTBV) were submitted to our laboratory for viability analysis using two methods of Trypan Blue Exclusion and tetrazolium salt (MTT) assays.

Results

During the study period, 36 patients received cadaveric allograft at our institution. The average total burn surface area (TBSA) for this group of patients was 40% and all patients received cadaveric skin as a temporizing measure prior to definitive grafting. Cadaveric allograft was used in complicated cases such as wound contamination, where synthetic dressings had failed. Viability tests showed fewer than 30% viability in processed allografts when compared to fresh skin following the thawing process. However, the skin structure in the frozen allografts was histologically well preserved.

Conclusion

Cryopreserved cutaneous cadaveric allograft has a positive and definite role as an adjunct to conventional dressing and grafting where available, particularly in patients with large TBSA burns. The low viability of cryopreserved specimens processed at DTBV suggests that cell viability in cadaveric allograft may not be essential for its clinical function as a wound dressing or even as permanent dermal substitute.  相似文献   
67.
The use of gadolinium-based hepatocyte-specific contrast agents (HSCAs) has increased markedly since their introduction, and hepatocellular phase imaging performed with an HSCA is now a key part of the standard magnetic resonance (MR) imaging work-up for focal liver lesions. An understanding of the mechanisms of action of HSCAs helps ensure their effective use. The optimal delay for hepatocellular phase image acquisition differs between the two currently available HSCAs, gadoxetic acid and gadobenate dimeglumine, and MR imaging protocols must be adjusted accordingly. In addition, familiarity with typical and atypical appearances of benign and malignant focal liver lesions at HSCA-enhanced hepatocellular phase MR imaging, along with knowledge of the processes that are most likely to produce atypical appearances, is required to achieve optimal diagnostic accuracy.  相似文献   
68.
The myelin‐associated protein Nogo‐A contributes to the failure of axon regeneration in the mammalian central nervous system (CNS). Inhibition of axon growth by Nogo‐A is mediated by the Nogo‐66 receptor (NgR). Nonmammalian vertebrates, however, are capable of spontaneous CNS axon regeneration, and we have shown that retinal ganglion cell (RGC) axons regenerate in the lizard Gallotia galloti. Using immunohistochemistry, we observed spatiotemporal regulation of Nogo‐A and NgR in cell bodies and axons of RGCs during ontogeny. In the adult lizard, expression of Nogo‐A was associated with myelinated axon tracts and upregulated in oligodendrocytes during RGC axon regeneration. NgR became upregulated in RGCs following optic nerve injury. In in vitro studies, Nogo‐A‐Fc failed to inhibit growth of lizard RGC axons. The inhibitor of protein kinase A (pkA) activity KT5720 blocked growth of lizard RGC axons on substrates of Nogo‐A‐Fc, but not laminin. On patterned substrates of Nogo‐A‐Fc, KT5720 caused restriction of axon growth to areas devoid of Nogo‐A‐Fc. Levels of cyclic adenosine monophosphate (cAMP) were elevated over sustained periods in lizard RGCs following optic nerve lesion. We conclude that Nogo‐A and NgR are expressed in a mammalian‐like pattern and are upregulated following optic nerve injury, but the presence of Nogo‐A does not inhibit RGC axon regeneration in the lizard visual pathway. The results of outgrowth assays suggest that outgrowth‐promoting substrates and activation of the cAMP/pkA signaling pathway play a key role in spontaneous lizard retinal axon regeneration in the presence of Nogo‐A. Restriction of axon growth by patterned Nogo‐A‐Fc substrates suggests that Nogo‐A may contribute to axon guidance in the lizard visual system. J. Comp. Neurol. 525:936–954, 2017. © 2016 Wiley Periodicals, Inc.  相似文献   
69.
Neuroinflammation mediated by chronically activated microglia, largely caused by abnormal accumulation of misfolded α‐synuclein (αSyn) protein, is known to contribute to the pathophysiology of Parkinson's disease (PD). In this work, based on the immunomodulatory activities displayed by particular heat‐shock proteins (HSPs), we tested a novel vaccination strategy that used a combination of αSyn and Grp94 (HSPC4 or Gp96) chaperone and a murine PD model. We used two different procedures, first, the adoptive transfer of splenocytes from αSyn/Grp94‐immunized mice to recipient animals, and second, direct immunization with αSyn/Grp94, to study the effects in a chronic mouse MPTP‐model of parkinsonism. We found that both approaches promoted a distinct profile in the peripheral system—supported by humoral and cellular immunity—consisting of a Th1‐shifted αSyn‐specific response accompanied by an immune‐regulatory/Th2‐skewed general phenotype. Remarkably, this mixed profile sustained by αSyn/Grp94 immunization led to strong suppression of microglial activation in the substantia nigra and striatum, pointing to a newly described positive effect of anti‐αSyn Th1‐responses in the context of PD. This strategy is the first to target αSyn and report the suppression of PD‐associated microgliosis. Overall, we show that the αSyn/Grp94 combination supports a distinct and long‐lasting immune profile in the peripheral system, which has an impact at the CNS level by suppressing chronic microglial activation in an MPTP model of PD. Furthermore, our study demonstrates that reshaping peripheral immunity by vaccination with appropriate misfolding protein/HSP combinations could be highly beneficial as a treatment for neurodegenerative misfolding diseases.  相似文献   
70.
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