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151.
Complex injuries of the foot are often overlooked, especially in the multiple injured patient, and they then lead to major loss of function. When the mechanism of injury suggests involvement of the foot, a clinical examination of the lower extremities should be included in the primary diagnostic procedures implemented in the multiply injured patient, followed by radiological examination once the patient's condition is stable. The condition of the soft tissues is of decisive importance in the prognosis of complex foot injuries, regardless of whether the damage to the foot is one component of a polytrauma or an isolated injury, which can also be life threatening. The diagnostic examinations selected should be adapted to the severity of the injuries in the particular multiply injured patient. Successful therapy involves stable internal fixation of injuries to bones and joints, though the external fixation options should be considered in the first instance, and carefully selected methods of temporary and definitive soft tissue reconstruction. The aim of treatment is the best possible reconstruction of the foot as a functional weight-bearing unit with intact soft tissue cover and a natural form. Good results can be achieved when there is close interdisciplinary cooperation between trauma (orthopedic) and plastic surgeons. Patient with severe injuries of this kind should be transferred to a trauma center as the first step toward this end.  相似文献   
152.
Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP.  相似文献   
153.
Because of the insecure status of knowledge about the actual pathomorphologic changes that occur in whiplash injury, the diagnosis, therapy, and expert assessment of its sequelae still present considerable problems. These are further compounded by the high incidence of this injury in Germany and the very good insurance cover the persons concerned generally have. The initial diagnostic examinations should include a detailed and well-documented clinical examination, and the most precise record possible of how the injury was sustained should be elicited. Plain X-rays are standard diagnostic procedures; functional X-rays and MRI are recommended when instability is suspected or neurological symptoms are present. The first aim of treatment must be the relief or attenuation of pain, followed by improvement of the function. Immobilization of the cervical spine by means of a Schanz collar is rather detrimental. Varied vegetative symptoms require the involvement of different specialists in the treatment at an early stage. Expert assessment for insurance purposes is complicated because the consequences of the accident cannot be objectified, and expecially because the insurance companies require differentiation between the degenerative changes that were present before the injury was sustained in many cases and the symptoms actually caused by the injury.  相似文献   
154.
目的 探讨热应激条件下对血管内皮细胞增殖的影响 ,进一步从DNA损伤后P5 3mRNA、P2 1mRNA表达改变角度探讨增殖调控的机理。方法 以建立的血管内皮细胞热应激 (4 3℃ ,2小时 )为实验模型 ,应用流式细胞仪观察热应激后血管内皮细胞株ECV30 4的细胞周期变化 ,单细胞凝胶电泳方法观察热应激对血管内皮细胞DNA的损伤 ,RT PCR检测P5 3mRNA、P2 1mRNA表达改变情况。结果 热应激可使血管内皮细胞DNA产生显著损伤 (P <0 .0 5 ) ,继而P5 3mRNA表达增高 ,并促进P2 1mRNA的上调表达 ,最终使细胞产生G1期阻滞。结论 热应激可损伤血管内皮细胞DNA ,并通过P5 3、P2 1通路抑制细胞增殖  相似文献   
155.
Summary— Experimental and clinical data clearly demonstrate that calcium antagonists (CA) may have an action on the central nervous system (CNS). The cerebrovascular action of CA justifies their use in cerebral ischaemia, vasospasm and hypoxia. Several clinical trials have demonstrated such beneficial effects. On the other hand a number of reports indicate that CA may have a direct neuronal effect, although most of such trials have not been verified or are mere case reports. In addition, the large number of conditions susceptible to being corrected by CA is impressive: epilepsy, pain, dystonia, dyskinesia, psychiatric conditions, etc. Other papers are disconcerting that report extrapyramidal disorders induced by flunarizine and cinnarizine in the elderly, whereas nicardipine does not produce such side effects and may even alleviate some parkinsonian symptoms. In various experimental models (e.g. stroke, oedema), pharmacological effects have been shown to vary from one compound to the other. Two main questions are yet to be answered: 1) has the direct neuronal effect of CA been clearly established? 2) are the multiple clinical effects on the CNS really linked to calcium antagonism?  相似文献   
156.
新型骨与软骨组织工程支架材料制备及其性能研究   总被引:14,自引:1,他引:13  
目的:研究符合骨与软骨组织工程制备技术要求的新型支架复合材料;并确定其性能与结构优化设计的主要参数指标。方法:按不同CPPf(聚磷酸钙纤维)/PLL(L-聚乳酸)重量比及相同CPPfPLLA/NaCl颗粒重量比,采用溶铸颗粒沥取(Solventcasting particulte-leaching)法轩系列CPPf/PLLA支架复合材料;液体置换法,压缩性能测试及扫描电子显微镜观察其密度,孔隙度压缩模量及微结构特征;材料样品体外人工降解液直接浸渍法判定其生物降解性能,并观测其生物降解率,压缩碍及微结构由微孔海绵状过渡为纤维网状。随着支架材料在人工降解液中降解时间的延长,其降解率以0%-13.2%线性递增;压缩模量呈线性降低至1.10-2.78MP;材料横截面微结构则发生相应改变。结论 CPPf/PLLA支架复合材料具有高孔隙度的三维立体结构,良好的抗压缩性能和和解性能,经进一步优化设计后,可成为结构和性能符合各项要求的新与软骨组织工程支架材料。  相似文献   
157.
The helicity of the tryptathionine moiety of the phallotoxins has been recognized by comparison with cyclic tryptathionine tripeptides. In order to investigate the influence of the configuration of the component amino acids on the conformation of the cyclic peptides, six analogue thioether tripeptides containing L- and D-alanine and L- and D-cysteine, respectively, have been synthesized. The CD spectra of the peptides are very similar to each other, showing mirror images of the CD of phalloidin and, therefore, negative helicity. The spectra of the D-cysteine containing compounds differ from the L-cysteine containing compounds by their weakly positive ellipticity values around 270 nm. The cyclization reaction of Boc-Hpi-D-Ala-D-Cys(STrt)OCH3, along with the cyclic tripeptide, afforded a cyclic hexapeptide by dimerization. The CD spectrum of the dimer is very similar to that of phalloidin, thus pointing to a positive helicity of its two tryptathionine moieties. The dimeric thioether peptide forms a rather strong complex with Cu2+ ions.  相似文献   
158.
目的 研究妊娠期糖尿病与胎儿生长发育中糖代谢特点的关系。方法 选择妊娠期糖尿病25例(GDM组),正常孕妇20例(对照组),分别测孕妇空腹血糖、糖耐量、C肽、IGF-I、新生儿出生2h内空腹血糖,并依据新生儿出生体重分为大于胎龄儿组(LGA组,≥4000g),适于胎龄儿组(AGA组,2500-3999g)。结果 C肽及新生儿出生2h内空腹血糖GDM组与对照组差异有显著性;糖耐量各时点血糖值餐后2h血糖值LGA和AGA组差异有显著性。结论 血糖始终是影响胎儿生长发育的重要因素,孕妇餐后2h血糖水平与巨大儿的发生呈正相关。  相似文献   
159.
Cholecystokinin (CCK) is a putative peptide neurotransmitter present in high concentration in the cerebral cortex. By using techniques of in vitro receptor autoradiography, CCK binding sites in primate cortex were labeled with 125I-Bolton-Hunter-labeled CCK-33 (the 33-amino-acid C-terminal peptide) and 3H-CCK-8 (the C-terminal octapeptide). Biochemical studies performed on homogenized and slide-mounted tissue sections showed that the two ligands labeled a high-affinity, apparently single, saturable site. Autoradiography revealed that binding sites labeled by both ligands were anatomically indistinguishable and were distributed in two basic patterns. A faint and diffuse label characterized portions of medial prefrontal cortex, premotor and motor cortices, the superior parietal lobule, and the temporal pole. In other cortical areas the pattern of binding was layer-specific; i.e., binding sites were concentrated within particular cortical layers and were superimposed upon the background of diffuse label. Layer-specific label was found in the prefrontal cortex, anterior and posterior cingulate gyrus, somatosensory cortex, inferior parietal lobule, retrosplenial cortex, insula, temporal lobe cortices, and in the primary visual and adjacent visual association cortices. The areal and laminar localization of layer-specific CCK binding sites consistently coincided with the cortical projections of thalamic nuclei. In prefrontal cortex, CCK binding sites were present in layers III and IV, precisely paralleling the terminal fields of thalamocortical projections from the mediodorsal and medial pulvinar nucleus of the thalamus. In somatosensory cortex, the pattern of CCK binding in layer IV coincided with thalamic inputs arising from the ventrobasal complex, while in the posterior cingulate gyrus, insular cortex, and retrosplenial cortex, layer IV and lower III binding mirrored the laminar distribution of cortical afferents of the medial pulvinar. CCK binding in layers IVa, IVc alpha, IVc beta, and VI of primary visual cortex corresponded to the terminal field disposition of lateral geniculate neurons, whereas in adjacent visual association cortex, binding in layers III, IV, and VI faithfully followed the cortical distribution of projections from the inferior and lateral divisions of the pulvinar nucleus of the thalamus. We interpret the diffusely labeled binding sites in primate cortex as being associated with the intrinsic system of CCK-containing interneurons that are distributed throughout all layers and areas of the cortex. The stratified binding sites, however, appear to be associated with specific extrinsic peptidergic projections.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
160.
A low concentration of transition metal ions Co2+ and Ni2+ increases the inward current density in neurons from the land snail Helix aspersa. The currents were measured using a single electrode voltage-clamp/internal perfusion method under conditions in which the external Na+ was replaced by Tris+, the predominant external current carrying cation was Ca2+, and the internal perfusate contained 120 mM Cs+/0 K+; 30 mM tetraethylammonium (TEA) was added externally to block K+ current. In the presence of Co2+ (3 mM) or Ni2+ (0.5 mM) inward Ca2+ currents were stimulated normally by voltage-dependent activation of Ca2+ channels. There was a 5-10% decrease in the rate of rise of the inward current. The principal effect of Co2+ and Ni2+ in increasing the current density seems to be a decrease in the rate at which the inward currents decline during a depolarizing voltage pulse. The results may be due to a decrease in a voltage-dependent or Ca(2+)-dependent outward current and/or an inhibition of Ca2+ channel inactivation. Outward current under these conditions (zero internal K+) was significant and most likely due to Cs+ efflux through the voltage-activated or Ca(2+)-activated nonspecific cation channels. Co2+ is an extremely effective blocker of this outward current. These results are not an artifact of internal perfusion or the special ionic conditions. Intracellular recording of unperfused neurons in normal Helix Ringer's solution showed that the Ca(2+)-dependent action potential duration was increased significantly by low concentrations of Co2+. This result is consistant with the Co(2+)-dependent increase in inward (depolarizing) current seen in voltage-clamp experiments.  相似文献   
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