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121.
The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +/- 16 micrograms/dl (mean +/- SE) to 24 +/- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +/- 6 micrograms/dl to 12 +/- 1 micrograms/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disappearance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +/- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +/- 0.6%) at 9 h after intravenous injection of 59Fe chondroitin ferrous sulfate, there was no difference between the amount of 59Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the 59Fe once it has been released from the mononuclear phagocyte system into the plasma.  相似文献   
122.
It has been demonstrated that total parenteral nutrition (TPN) modulates the function of the hepatic reticuloendothelial system (RES). The objective of this study was to evaluate the impact of two different TPN lipid emulsions on the recovery of allograft RES function after orthotopic liver transplantation (OLTx). In a prospective, double-blind study, OLTx patients were randomly assigned to two treatment groups. Group I ( n=13) received a TPN regimen that included long-chain triglycerides (LCT). Group II ( n=9) received a TPN regimen that included a fat emulsion consisting of both medium-chain triglycerides (MCT) and LCT. At baseline, i.e., on days 2 or 3 after OLTx ( t1), before lipids for TPN were started, hepatic RES function was determined using the human serum albumin millimicrosphere technique (K-value, 1/min). A second measurement ( t2) was obtained after 7 days of TPN, including one of the study's two fat emulsions. The mean (+/- SD) K-value (1/min) was 0.48+/-0.16 in the LCT group and 0.55+/-0.28 in the MCT/LCT group at t1, and it improved to 0.62+/-0.21 in the LCT group and to 0.86+/-0.32 in the MCT/LCT group at t2. RES function recovery was significantly better in the MCT/LCT group ( P< or = 0.05). MCT/LCT emulsion appears to be the TPN fat emulsion of choice after OLTx as it seems to have less impact on hepatic RES recovery.  相似文献   
123.
植物抗体及其应用   总被引:1,自引:1,他引:0  
20世纪80年代末科学家将抗体基因转入烟草表达,标志着植物抗体的诞生.人类既可以以植物为生物反应器异源表达和生产具有药用及商业价值的蛋白质;也可用抗体在植物体中进行免疫调节,以研究植物生理代谢机制,或增加植物抵抗病虫害的能力.本文旨对植物抗体的优越性、表达生产及其在医药学、植物抗病及代谢等领域的进展进行综述和讨论.  相似文献   
124.
1992年美国放射学会制定了乳腺影像学报告及数据系统(breast imaging reporting and data system,BI-RADS),2003年第四版修订时包括了超声诊断(BI-RADS-US)。本文旨在初步探讨BI-RADS-US对于乳腺良恶性病变鉴别诊断的能力。我们收集了2006年1月至2007年3月期间、获得病理诊断的乳腺占位性病变共69例72灶。均为女性,年龄14-83岁,平均41.6岁。首先根据一般的非BI-RADS标准,做出良恶性鉴别。然后用BI-RADS-US标准进行鉴别和分级(0-6级),其中2级和3级为良性和良性可能性大,4级为性质待定,5级为恶性可能性大。计算并比较上述两种方法的准确性、敏感性、特异性。结果在72病灶中,根据非BI-RADS标准,诊断为良性者40灶,符合病理诊断者38灶(95.0%),诊断为恶性者23灶,符合病理者18灶(78.3%);诊断为性质待定者9灶。根据BI-RADS-US标准和分级,2级和3级共有37灶,与病理结果符合者为36灶(97.2%);5级有31灶,与病理符合者为22灶(71.0%);4级有4灶。非BI-RADS和BI-RADS-US的准确性各为83.3%和81.9%(P=1.000),敏感性各为91.7%和95.8%(P=1.000),特异性各为79.2%和75.0%(P=0.754)。总之,第一版BI-RADS-US在乳腺良恶性病变鉴别诊断方面的初步应用表现出较高的敏感性,而与非BI-RADS方法比较则尚无明显差别。  相似文献   
125.
This study aimed to determine the effect of acute brucellosis on the auditory system. Forty-two patients with acute brucellosis were evaluated clinically, and with serological and audiological tests, before and after treatment. Hearing threshold averages were calculated at 11 different frequencies (250-8000 Hz) of the auditory airway, and statistical analysis was performed. The average hearing thresholds were > 20 dB, with standard audiometry at 6000-8000 Hz, and < 20 dB at all other frequencies. After treatment, the average auditory threshold decreased to < 20 dB at 6000-8000 Hz (p < 0.0001). Pure-tone hearing thresholds were improved at all frequencies after treatment, with statistically significant differences at all frequencies except 12,000, 14,000 and 16 000 Hz (p < 0.05). There was no permanent hearing loss caused by acute brucellosis, and hearing thresholds were restored after treatment. It was concluded that acute brucellosis affects the auditory system, especially at high frequencies, and that patients with all forms of brucellosis should be evaluated for hearing loss.  相似文献   
126.
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects.  相似文献   
127.
128.
Physiologic assessment of diseases of the motor unit from the anterior horn cells to the muscles relies on a combination of needle electromyography (EMG) and nerve conduction studies (NCS). Both require a unique combination of knowledge of peripheral nervous system anatomy, physiology, pathophysiology, diseases, techniques, and electricity is necessary. Successful, high‐quality, reproducible EMG depends on the skills of a clinician in patient interaction during the physical insertion and movement of the needle while recording the electrical signals. These must be combined with the skill of analyzing electric signals recorded from muscle by auditory pattern recognition and semiquantitation. 10 , 52 This monograph reviews the techniques of needle EMG and waveform analysis and describes the types of EMG waveforms recorded during needle EMG. © 2009 Wiley Periodicals, Inc. Muscle Nerve 39: 244–270, 2009  相似文献   
129.
The disintegrin and metalloproteinase 10 (ADAM10) is a membrane‐anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co‐cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG‐SC co‐cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate‐based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve. © 2009 Wiley‐Liss, Inc.  相似文献   
130.
妇女围孕期增补叶酸能够有效预防神经管缺陷等疾病的发生。随着对叶酸研究的不断深入,叶酸补充中出现了诸多问题。本文简要综述了叶酸在服用方式以及基础和临床研究中出现的值得讨论、已经引起关注和需要进一步研究探讨的问题,并提出了深入研究叶酸可能的发展趋势。  相似文献   
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