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991.
Introduction  The management of acute acromioclavicular joint (ACJ-) injuries especially of type III is still controversial. Methods  In this retrospective study the results of early ACJ reconstructions immediately after trauma (group early repair, ER) were compared with the results of delayed reconstructions in patients who first got conservative treatment and failed after some time (group delayed repair, DR). Overall, 49 patients were analysed clinically and radiographically with a mean follow-up of 53 months (range 20–92). In group ER twenty-nine patients were treated with a modified Phemister technique according to Mayr including a PDS coracoclavicular sling and temporary K- wire fixation. In group DR twenty patients were treated with a modified Weaver–Dunn-procedure with additionally transposition of the coracoacromial ligament and AC-joint resection. Results  A comparison of the overall results revealed a statistically significant better outcome in the early repair group, regarding the Constant Score, the degree of acromioclavicularjoint-reduction, numbers of complications and patient`s satisfaction. Conclusion  Our results point out that early reconstruction of ACJ-injuries in type III–V avoids the inferior clinical results of delayed reconstructions using a modified Weaver–Dunn-procedure.  相似文献   
992.
Microcirculatory dysfunction, reduced oxygen supply and thus impaired hepatosplanchnic organ function, play a pivotal role in the clinical manifestation of sepsis and septic shock. Early correction of the perfusion mismatch is essential to maintain end-organ and gut mu-cosa barrier function and thus to prevent bacterial translocation, bacteraemia and possible multiple organ failure. This review will outline the clinical tightrope-walk optimizing hepa-tosplanchnic oxygen supply while maintaining adequate end-organ perfusion pressure and highlight the diagnostic challenges and limitations faced in clinical practice.  相似文献   
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994.
FXPRLamides are insect neuropeptides that mediate such diverse functions as pheromone biosynthesis, visceral muscle contraction, and induction of diapause. Although multiple forms occur in every insect studied so far, little is known about a possible functional differentiation and/or differences in the cellular expression pattern of these messenger molecules. In this study, we performed a mass spectrometric survey of all FXPRLamide-expressing neurosecretory neurons in the CNS of Periplaneta americana. That species combines a very well characterized peptidergic system with relatively easy accessible neurosecretory cells suitable for dissection. In addition to the extensive mass spectrometric analyses of single cells, the projection of the FXPRLamide-expressing neurons was studied with three antisera specifically recognizing different FXPRLamides. The following conclusions can be drawn from this first comprehensive peptidomic approach on insect neurons. 1) A high degree of differentiation in the expression of FXPRLamides exists; not fewer then four cell types containing different sets of FXPRLamides were observed. 2) A low level of colocalization with other neuropeptides was found in these neurons. 3) A comparison with FXPRLamide-expressing neurons of other insects shows a high degree of conservation in the localization and projection of these neurons, which is not corroborated by a similar conservation of the corresponding peptide sequences. 4) Although the methods for cell identification, dissection, and sample preparation for mass spectrometry were kept as simple as possible, it was unambiguously shown that this approach is generally suitable for routine analysis of single identified neurons of insects.  相似文献   
995.
Huntington disease (HD) is a progressive neurodegenerative disorder characterized by emotional, cognitive, and motor dysfunctions. Aggregation of huntingtin is a hallmark of HD and, therefore, a crucial parameter for the evaluation of HD animal models. We investigated here the regional, cellular, and subcellular distribution of N-terminal huntingtin aggregates and associated neuropathological changes in the forebrain of a rat transgenic for HD (tgHD). The tgHD rat brain showed enormously enlarged lateral ventricles and a similar atrophy of cortical and subcortical areas as known in HD patients. Huntingtin aggregates of varying size and forms were regionally identified in neuronal nuclei, cytoplasm, dendrites, dendritic spines, axons, and synaptic terminals, closely resembling the results described earlier for human HD brains and in established HD mouse models. Huntingtin aggregates in mitochondria support mitochondrial dysfunction as contributing to the disease pathogenesis. Dark cell degeneration was reminiscent of results in HD individuals and HD mouse models. Interestingly, huntingtin aggregates were especially well accumulated in two interacting limbic forebrain systems, the ventral striatopallidum and the extended amygdala, which may contribute to the early onset of emotional changes observed in the tgHD rat. In conclusion, the tgHD rat model reflects to a remarkable extent the cellular and subcellular neuropathological key features as observed in human HD and HD mouse brains and hints of changes in limbic forebrain systems, which may elucidate the emotional dysfunction in the tgHD rat and affective disturbances in HD patients.  相似文献   
996.
997.
998.
Multiple Sclerosis (MS) is considered to be a T cell-mediated autoimmune disease. An attractive strategy to prevent activation of autoaggressive T cells in MS, is the use of altered peptide ligands (APL), which bind to major histocompatibility complex class II (MHC II) molecules. To be of clinical use, APL must be capable of resisting hostile environments including the proteolytic machinery of antigen presenting cells (APC). The current design of APL relies on cost- and labour-intensive strategies. To overcome these major drawbacks, we used a deductive approach which involved modifying proteolytic cleavage sites in APL. Cleavage site-directed amino acid substitution of the autoantigen myelin basic protein (MBP) resulted in lysosomal protease-resistant, high-affinity binding peptides. In addition, these peptides mitigated T cell activation in a similar fashion as conventional APL. The strategy outlined allows the development of protease-resistant APL and provides a universal design strategy to improve peptide-based immunotherapeutics.  相似文献   
999.
Bis-[(p-methoxybenzyl)cyclopentadienyl] titanium dichloride, better known as Titanocene Y, is a newly synthesized transition metal-based anticancer drug. We studied the antitumor activity of Titanocene Y with concentrations of 2.1, 21 and 210 micromol/l against a freshly explanted human breast cancer, using an in-vitro soft agar cloning system. The sensitivity against Titanocene Y was highly remarkable in the breast cancer tumor in the full concentration range. Titanocene Y showed cell death induction at 2.1 micromol/l, well comparable to cisplatin, given at a concentration of 1.0 micromol/l. A further preclinical development of Titanocene Y was warranted and therefore an MCF-7 human breast cancer xenograft nonobese diabetic/severe combined immunodeficient mouse model was used. Titanocene Y was given for 21 days at 30 mg/kg/day (75% of the maximum tolerable dose of Titanocene Y), which resulted in the reduction of the tumor volume to around one-third, whereas no mouse was lost because of the surprisingly low toxicity of Titanocene Y.  相似文献   
1000.
The antimycobacterial quinolones 1-methyl-2-undecyl-4-quinolone, dihydroevocarpine and evocarpine as well as the indoloquinazoline alkaloids rutaecarpine and evodiamine - all from the Chinese medicinal herb Evodia rutaecarpa - were tested in two in vitro assays, for cytotoxicity and interaction with p-glycoprotein (p-gp). Cytotoxicity was measured in a cell proliferation assay against CCRF-CEM leukemia cells and their p-gp over-expressing subline CEM/ADR5000. An assay monitoring the p-gp-dependent accumulation of the dye calcein in porcine brain capillary endothelial cells (PBCECs) was used to study interactions of the test substances with this efflux pump. Rutaecarpine and evodiamine showed quite high toxicity with IC (50) values from 2.64 to 4.53 microM and were weak modulators of p-gp activity. The degrees of resistance in CEM/ADR5000 towards the saturated quinolones 1-methyl-2-undecyl-4-quinolone and dihydroevocarpine were between 3 and 4. In the calcein assay, these two quinolones were shown to be moderate modulators of p-gp activity. Evocarpine, on the other side, is not transported by p-gp, and showed only slight toxicity at the highest test concentration of 30 microM.  相似文献   
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