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91.
The main accepted principle to treat Kienb?ck disease is to decompress the lunate. Radius shortening is the most used technique. Three transverse osteotomies of the radius are described: neutral shortening osteotomy, lateral closing wedge osteotomy, and medial closing wedge osteotomy. Shortening the radius decompress the lunate and more or less the scaphoid. This deviates axial constraints toward ulna and triangular fibrocartilage complex. But the ulnar wrist is not able to support important axial constraints. The authors propose a solution to decompress only the lunate and not the scaphoid. This solution deviates axial constraints toward the scaphoid, which is naturally the most capable bone to support it. The authors describe a new radial nontransverse decompression wedge osteotomy. It allows to shorten the radius in front of the lunate. The fixation is done with a dorsal staple. To complete lunate decompression, authors propose to associate a metaphysal ulnar oblique shortening, essentially if ulnar variance is neutral or positive. The preliminar results on 10 cases are presented.  相似文献   
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We investigated whether further in-vitro culture of human multicellular embryos that survive cryopreservation can select the viable embryos for transfer. Embryos for cryopreservation were supernumerary multicellular embryos obtained after in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatments, with <20% of their volume filled with anucleate fragments. These had been cryopreserved using a slow-freezing and slow-thawing protocol with 1.5 M dimethylsulphoxide as the cryoprotectant. From the start of our cryopreservation programme until September 12, 1994, the thawing strategy was to thaw frozen embryos up to the exact number needed for transfer. Embryos for transfer were selected on the basis of their morphological appearance and embryo transfer to the patient was done on the day of thawing. From September 12, 1994 onwards we used a more selective thawing strategy where a cohort of up to a maximum of 12 frozen embryos per patient is thawed from which embryos of the best morphological quality, and which are furthest advanced in terms of cleavage after a 24 h in-vitro culture period in Menezo B2 medium, are selected. We took delivery rates, embryo implantation rates and birth rates into account to see if there is any difference between the following three types of transfers used: 187 transfers exclusively of embryos having continued to cleave after thawing, 107 mixed transfers of embryos with and without further cleavage and 53 transfers exclusively of embryos with no further cleavage. The overall outcome in terms of delivery rate and embryo implantation and birth rates were not different between the new and the earlier thawing policies (6.6, 5.2 and 3.6% versus 6.0, 4.1 and 2.7% respectively). Only when a distinction was made between transfers on the basis of the presence of embryos with further cleavage, did the advantage of selection on the basis of cleavage capacity become evident. Significantly higher delivery and embryo implantation and birth rates (11.2, 7.7 and 6.5% respectively) were recorded with transfers exclusively of embryos with further cleavage versus mixed transfers of embryos with and without further cleavage (1.9, 2.9 and 0.6% respectively). Fifty-three transfers exclusively of embryos with no further cleavage did not lead to any delivery. Our results demonstrate that selection of human multicellular embryos which survive cryopreservation and continue to cleave in vitro can significantly improve the delivery rate per transfer and the implantation rate per transferred embryo.   相似文献   
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Hexahydro-sila-difenidol and eight analogues behaved as simple competitive inhibitors of [3H]N-methyl-scopolamine binding to homogenates from human neuroblastoma NB-OK 1 cells (M1 sites), rat heart (M2 sites), rat pancreas (M3 sites), and rat striatum 'B' sites (M4 sites). Pyrrolidino- and hexamethyleneimino analogues showed the same selectivity profile as the parent compound. Hexahydro-sila-difenidol methiodide and the methiodide of p-fluoro-hexahydro-sila-difenidol had a higher affinity but a lower selectivity than the tertiary amines. Compounds containing a p-methoxy, p-chloro or p-fluoro substituent in the phenyl ring of hexahydro-sila-difenidol showed a qualitatively similar selectivity profile as the parent compound (i.e., M1 = M3 = M4 greater than M2), but up to 16-fold lower affinities. o-Methoxy-hexahydro-sila-difenidol has a lower affinity than hexahydro-sila-difenidol at the four binding sites. Its selectivity profile (M4 greater than M1, M3 greater than M2) was different from hexahydro-sila-difenidol. Replacement of the central silicon atom of hexahydro-sila-difenidol, p-fluoro-hexahydro-sila-difenidol and their quaternary (N-methylated) analogues by a carbon atom did not change their binding affinities significantly. The four muscarinic receptors showed a higher affinity for the (R)- than for the (S)-enantiomers of hexahydro-difenidol, p-fluorohexahydro-difenidol and their methiodides. The stereoselectivity varied depending on the receptor subtype and drug considered.  相似文献   
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The Rab genes have recently been cloned and sequenced in mammals, and their products represent good candidates for low molecular weight guanosine triphosphate-binding proteins involved in the regulation of intracellular transport of vesicles in higher eukaryotes. Remarkably, each of the Rab proteins appears to be associated with a distinct step of either the exocytic or endocytic pathway. In particular, Rab6p has been localized to the outermost Golgi cisternae in normal rat kidney cells, where its function remains unclear. In this work, we have carried out a series of immunocytochemical analyses of the subcellular distribution of Rab6p in a polarized cell, the electrocyte of Torpedo marmorata, to elucidate the molecular mechanisms involved in the sorting and targeting of synaptic proteins. We report that, aside from its Golgi localization, the bulk of Rab6p associates with clusters of post-Golgi vesicles, primarily those located at the cytoplasmic face of the innervated membrane of the electrocyte. Consequently, Rab6p presents a polarized distribution in this cell. Furthermore, we show that this distribution is dependent upon the integrity of the microtubule network of the electrocyte. These data are coherent with the notion that Rab6p is involved in the regulation of membrane traffic from the trans-Golgi network to the innervated plasma membrane, delivering, by way of a microtubule-based organelle transport mechanism, synaptic proteins to their appropriate locations.  相似文献   
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In order to examine if the transfer of more than three embryos has any beneficial effect on the outcome of intracytoplasmic sperm injection (ICSI) cycles in women aged > 40 years, a retrospective analysis was made of all the ICSI cycles which were performed in this age group from 1 October 1991 to 31 December 1995. A total of 525 cycles was performed in 321 patients. In 413 cycles, at least one normally fertilized embryo was available for transfer. In 271 cycles, one to three embryos were replaced while in the remaining 142 cycles at least four embryos were replaced. There was no difference in implantation rate (number of gestational sacs/number of embryos transferred), after the transfer of one to three embryos (5.2%), compared with the transfer of at least four embryos (5.1%). The pregnancy rate/embryo transfer and the clinical pregnancy rate/embryo transfer were, however, higher when at least four embryos were replaced than was the case with one to three embryos (27.5 versus 11.8%, P < 0.0001 and 20.42 versus 9.96%, P < 0.005, respectively). There were no statistically significant differences in the delivery rates, multiple pregnancy rates or spontaneous abortion rates. The pregnancy rate and the clinical pregnancy rate after ICSI in women > or = 40 years of age are related to the number of embryos replaced.   相似文献   
98.
Background: The infusion of several liters of crystalloid solution at room temperature may significantly contribute to intraoperative hypothermia because warming fluid to core temperature requires body heat. The aim of this study was to evaluate the effect of delivering warmed intravenous (IV) fluid to the patient on preventing intraoperative hypothermia.
Methods: Intraoperative core and mean skin temperatures were measured during prolonged abdominal surgery in 18 patients randomly divided into two groups according to intraoperative IV fluid management. In 9 patients (control group) all IV fluids infused were at room temperature. In the other 9 patients (group receiving warmed fluids) all IV fluids were warmed using an active IV fluid tube-warming system. In all 18 patients a warming blanket covered the skin surface available for cutaneous warming. Intraoperative changes in total body heat content (kJ) were calculated from core and mean skin temperatures.
Results: At the end of surgery, core temperature was 36.7±0.2°C in the group receiving warmed fluids and 35.8±0.2°C in the control group ( P <0.05). The estimated reduction in heat loss provided by warming IV fluid was 217 kJ, a value very close to the theoretical value expected from thermodynamic calculation. During recovery, one patient shivered in the group receiving warmed fluids and seven in the control group ( P <0.05).
Conclusion: In conclusion, infusion of warmed fluids, combined with skin-surface warming, helps to prevent hypothermia and reduces the incidence of postoperative shivering.  相似文献   
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