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1.
Intrastriatal transplantation of striatal neuroblasts from human fetuses is a promising approach for treatment of Huntington's disease, on the basis of many experimental animal studies and, most recently, pilot clinical trials. Technically, several issues remain to be resolved (e.g., the precise site of dissection of the fetal tissue; the number and location of the fetal striatal implants; or the use of immunosuppressive therapy), and await larger-scale trials and purposely designed protocols. Further clinical data must also be obtained, and preliminary promising results must be replicated in a patient group large enough to provide conclusive results. It is important to establish (1) the amount of clinical benefit provided to the patient by the grafted cells; (2) the anticipated duration of clinical benefits; and (3) the secondary rate of decline after the benefit of the graft has been overbalanced. Evaluation of these parameters will require very long-term follow-up of the patients involved, over several years after grafting, before the technique can eventually be proposed widely to patients.  相似文献   
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Journal of Neurology - The Clinch Token Transfer Test (C3t) is a bi-manual coin transfer task that incorporates cognitive tasks to add complexity. This study explored the concurrent and convergent...  相似文献   
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Declarative memory is a long-term store for facts, concepts and words. Procedural memory subserves the learning and control of sensorimotor and cognitive skills, including the mental grammar. In this study, we report a single-case study of a mild aphasic patient who showed procedural deficits in the presence of preserved declarative memory abilities. We administered several experiments to explore rule application in morphology, syntax and number processing. Results partly support the differentiation between declarative and procedural memory. Moreover, the patient's performance varied according to the domain in which rules were to be applied, which underlines the need for more fine-grained distinctions in cognition between procedural rules.  相似文献   
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Background

We present here the first reported cases of patients undergoing gastric bypass with a hybrid technique that involves a new concept of percutaneous instruments and provides the advantages of minimally invasive single-port surgery while maintaining the triangulation, safety, and timing of operative procedures.

Methods

This was a prospective pilot study of eight patients selected for gastric bypass between December 2011 and January 2012 and treated by a technique that combined single SSL port and percutaneous surgical set PPS. We performed hand-sewn gastrojejunostomy in all cases. We analyzed preliminary results at 1 month and focused on the feasibility of the technique, duration of surgery, perioperative complications, and cosmetic results. The Ethics Committee of our institution approved this study and we obtained the informed consent of each patient.

Results

We completed the procedure successfully in all patients. No conversions to laparotomy or classic laparoscopy were required. The average time of surgery was 112 min (85–155). Length of hospital stay was 4 days (3–5). One patient was re-admitted on the seventh postoperative day for gastrointestinal bleeding from the gastrojejunostomy suture and treated by endoscopic clipping. Residual scars were less than 2 cm for the single midline port and 2 mm for the percutaneous instruments.

Conclusions

This new technique combines the advantages of single-port surgery with the safety of conventional laparoscopy by using percutaneous instruments and leaves minimal scarring. It is likely that the use of percutaneous instrumentation will become widespread in all areas of laparoscopic surgery.  相似文献   
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Production and consumption of methane in freshwater lake ecosystems   总被引:2,自引:0,他引:2  
The atmospheric concentration of methane (CH4), a major greenhouse gas, is mainly controlled by the activities of methane-producing (methanogens) and methane-consuming (methanotrophs) microorganisms. Freshwater lakes are identified as one of the main CH4 sources, as it was estimated that they contribute to 6-16% of natural CH4 emissions. It is therefore critical to better understanding the biogeochemical cycling of CH4 in these ecosystems. In this paper, the effects of environmental factors on methanogenic and methanotrophic rates are reviewed and an inventory of the methanogens and methanotrophs at the genus/species level in freshwater lakes is given. We focus on the anaerobic oxidation of methane, which is a still poorly known process but increasingly reported in freshwater lakes.  相似文献   
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The metastatic potential of tumors is dependent on the ability of tumor cells to degrade extracellular matrix components by the expression of matrix metalloproteinases (MMPs) and to induce vascularisation of the tumor tissue. Thus, expression of MMPs and the number of blood vessel in tumor tissue may serve as prognostic markers of aggressive and metastasizing tumor growth. We have determined the vascularisation and the expression of MMP-2 by immuno-histochemical staining of 19 benign and 75 malignant breast tissue specimens with CD31- and MMP-2 specific antisera. The degree of vascularisation was expressed by intratumoral microvascular density (IMD), which takes into account all vessels present in a hot spot irrespective of their size. In addition, we have introduced a novel parameter, vascular grading (VG), which describes the percentage of small microvessels of <20 microm in diameter in the total number of blood vessels. IMD tended to indicate an elevated risk for metastasis formation and disease recurrence, while VG did not correlate with metastasis formation. Similarly, MMP-2 expression neither correlated with the clinical outcome of the disease nor with the classical histo-pathological parameters such as stage, grade, lymph node involvement and estrogen receptor status. Tumor cell-specific MMP-2 expression, however, showed a highly significant correlation with VG but not with IMD. These results indicate that MMP-2 expression is rather involved in the formation of small capillaries than in vessel maturation and tumor cell invasion. Thus, MMP-2 expression by tumor cells may serve as indicator of strong angiogenic induction potential of breast tumor cells.  相似文献   
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