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21.
The impetus for the devolopment of living related liver programmes lies with donor shortage, which relates inversely to the success of generating cadaveric donors. A shrinking or non-existent cadaveric donor pool leads to an increased death rate among potential recipients awaiting transplantation. The living related liver programmes have by and large been successful, though it is accepted that there is potentially a significant risk to the donors. The technique of live donor liver transplantation is clearly here to stay, but the selection of suitable donors is between the family and the unit. Consequently, because of the lack of international guidelines, the programmes are open to abuse. Steps should be taken to establish either mechanisms of control or a worldwide register to combat this potential.  相似文献   
22.
胆管癌相关抗原(CCRA)是我们从人胆管癌组织中提取的一种新的肿瘤标志物。建立了检测CCRA的ELISA方法,检测了40例正常人及268例良恶性疾病病人血清的CCRA浓度,后者包括胆管癌36例、原发性肝癌40例、胰腺癌26例、胃癌31例、结直肠癌34例、肺癌17例、肝硬变20例、胆石症40例及胃溃疡24例。结果显示:40例正常对照组的血清CCRA浓度为(14.38±7.34)μg/ml(x±s),正常上限为28.95μg/ml(x+2s);血清CCRA诊断胆管癌的敏感性是77.78%,明显高于其它肿瘤组(0~25)%(P<0.001),特异性是(75~100)%。认为对于胆管癌的诊断,CCRA可能是一种较特异的肿瘤相关抗原。  相似文献   
23.
Auditory event related magnetic fields were measured using an odd-ball paradigm in which the rare event was a tone of short duration, D2, and the frequent one a tone of longer duration, D1. The subjects were required to attend to and count the number of rare stimuli. In the average across target stimuli a mismatch field (MMF) occurs and the dependence of the MMF, especially its latency, on the tone duration D2 is examined in detail. The location of an equivalent current dipole for the MMF-source is found and turns out to be at variance with earlier results. In addition to the MMF we propose a new component, here called MMF, which in time overlaps the magnetic equivalent of the P200 signal and which has a source location (equivalent current dipole) lying rather close to the MMF-source. The two sources are, however, active at latencies differing by a time equal to D2. We speculate that MMF indicates the onset of the process: "evaluation of tone-duration" while the MMF indicates the end of this process.  相似文献   
24.
Summary (1) Longitudinal muscle strips from the human small intestine (jejunum/ileum) responded to electrical field stimulation (1–50 Hz) with frequency-related primary contractions which were largely atropine- (3 M) sensitive. When the tone was raised by addition of galanin (0.3 – 1 M), prostaglandin (PG) E2 (1–10 M) or neurokinin A (NKA, 0.1 M), a frequency-related relaxation was evident which was potentiated by atropine. All the responses to field stimulation were abolished by tetrodotoxin (1 M), thus indicating their neural origin. (2) The atropine-sensitive primary contraction to field stimulation was virtually abolished by omega conotoxin fraction GVIA (CTX, 0.1–0.3 M) while the relaxations were CTX-resistant. The field stimulation-induced relaxations, which were observed in the presence of atropine and guanethidine (3 M), were also unaffected by apamin (0.1 M). (3) NKA and substance P (SP) produced a concentration- (1 nM–1 M for both peptides) related contraction, NKA being about 53 times more potent than SP. [Pro9]SP sulphone and [MePhe7]-NKB, selective agonists of the NK-1 and NK-3 receptor, respectively, were barely effective. On the other hand, [\Ala8]NKA(4–10), a selective NK-2 receptor agonist, had a potent contractile activity, similar to that of NKA. (4) Galanin (1 nM–1M) produced an atropine- and tetrodotoxin-resistant concentration-related contraction of longitudinal muscle of human isolated small intestine. The response to galanin did not show any sign of fading and was particularly suitable to study the evoked relaxations. (5) Calcitonin gene-related peptide (CGRP) (10–100 nM) consistently inhibited the nerve-mediated contractions of strips from the ileum while the effect on the jejunum was less pronounced. Vasoactive intestinal polypeptide (VIP, 0.1–1 M) inhibited nerve-mediated contractions both in the ileum and the jejunum. (6) These experiments indicate that both cholinergic excitatory and non-adrenergic non-cholinergic nerves affect motility of the longitudinal muscle of the human small intestine. Furthermore, several neuropeptides produce potent motor effects, the contractile response to tachykinins being apparently mediated by activation of NK-2 receptors.  相似文献   
25.
The changes of spatial EEG synchronisation during brisk and slow voluntary self-paced movements of the right and left index finger were analysed in 12 right-handed and 11 left-handed subjects. EEG was recorded from the left and right sensorimotor area using 24 closely spaced electrodes. A novel measure of spatial EEG synchronisation, -complexity, was computed separately for the left and right sensorimotor area in 64 overlapping one-second epochs representing 4.5 s of the pre-movement and 3.5 s of the post-movement period. -complexity was higher, hence spatial synchronisation was lower, in slow than in brisk movements, especially in the right-handed. A sustained increase of -complexity was observed during execution of a slow movement. A decrease of -complexity which was often associated with a brief burst of spatially synchronised 10-Hz oscillations occurred at the onset of extensor muscle contraction. We suggest that increased spatial EEG synchronisation at movement onset may prevent spillover of excitation from the sensorimotor hand area to other cortical regions. During movement, the cortical neuronal assemblies subserve distinct, specialised functions manifesting in increased -complexity.  相似文献   
26.
Twenty female albino rats were adapted to either 0 or 23 hr of food deprivation. Half of each group was then fed 0.125% quinine sulfate adulterated diet for seven days. Following the quinine feeding, ad lib feeding (refeeding) was instituted for 14 days. Several conclusions were drawn from the results: (1) rats on a deprivation schedule fail to show a predicted change to regulation on the basis of taste rather than calories; (2) rats on food deprivation actually increase their relative intake of water; (3) refeeding after a deprivation schedule does not lead to depression of initial intake below normal, but otherwise the process of recovery follows the same course as after total starvation.  相似文献   
27.
目的 研究党参多糖对缺氧缺血性脑损伤的抗氧化和神经保护作用及其机制。 方法 采用Rice法建立HIBI模型。假手术组和模型组灌胃给予生理盐水,模型加药组灌胃给予党参多糖。分别进行神经功能学评分,观察脑积水量,脑组织病理学改变,神经元细胞凋亡情况,脑组织脂质过氧化物水平,抗氧化和神经保护相关蛋白表达水平。 结果 党参多糖能显著改善模型大鼠神经功能、脑水肿(P<0.01)和病理改变,降低细胞凋亡率(P<0.01)和Bax表达(P<0.01),降低LDH和MDA含量(P<0.01);同时,上调Bcl-2表达(P<0.01)和SOD活性(P<0.01),增加bFGF、BDNF、PSD95、SYP、Nrf2和HO-1表达(P<0.01)。 结论 党参多糖对缺氧缺血性脑损伤具有抗氧化和神经保护作用,可能与介导Nrf2信号通路相关。  相似文献   
28.
29.
The results of cadaveric retransplantation in 55 recipients immunosuppressed with cyclosporine and prednisone were compared to 156 recipients of primary renal allografts. By 3 yr posttransplant, there is no significant difference in patient survival, but the yearly graft survival for primary (79%, 72%, 72%) as compared to retransplant (69%, 58%, 58%) recipients was significantly (p less than 0.05) better. There was no significant difference in rejection episodes or mean +/- SD serum creatinine (mg/dl) at 2 yr between primary (32%, 2.14 +/- 1.1) and retransplant (33%, 2.08 +/- 1.4) patients, respectively. Donor source, third kidneys, human leukocyte antigen AB and Dr matching, percent reactive antibody levels, and cause of first graft loss do not have significant impact on cyclosporine-treated retransplant outcome. However, retransplant patients who have lost a previous graft in less than 3 months continue to be at high risk for subsequent early graft loss. These results suggest that the combination of cyclosporine and prednisone is the preferred regimen for cadaveric retransplantation.  相似文献   
30.
Development of neural processes underlying integration of phonological and orthographic information were assessed by measuring event-related brain potentials (ERPs), judgment accuracies and reaction times (RTs) in 20 children (9-10 years) and 20 adults performing visual rhyme judgments. Half the trials were phonologically and orthographically congruent across the prime-target pairs (e.g., thrown-own, cake-own), and half were incongruent (e.g., gown-own, cone-own). For both children and adults, behavioral performance was most affected when different phonological representations had to be encoded from similar orthographic representations (e.g., gown-own), and the amplitudes of the N350 reflected effects of both rhyme and phonological/orthographic congruency. Latencies of the N350 were shorter over the left hemisphere only in adults, and phonological/orthographic incongruence produced greater delays in children's processing. Therefore, it appears that neural systems mediating rhyming judgments develop early; however, adults exhibit increased efficiency for left-hemisphere processing and are less affected by interference from incongruent phonological and orthographic codes.  相似文献   
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