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71.
This study examines one of the largest pedigrees with radial polydactyly type IV (uncomplicated polysyndactyly) comprising a total of 69 individuals, of whom 26 have been affected over six generations. Typical manifestations of the pedigree were bilateral radial and ulnar digital duplications, as well as syndactyly between the middle and ring fingers and the second and third toes. There was no craniofacial anomaly in any of the 17 cases examined physically. This observation suggests that radial polydactyly type IV and Greig craniofacial-synostosis syndrome with similar digital manifestations are clinically-distinct entities.  相似文献   
72.
A new silicone hollow fiber membrane oxygenator for extracorporeal membrane oxygenation (ECMO) was developed using an ultrathin silicone hollow fiber, with a 300 microm outer diameter and a wall thickness of 50 microm. The hollow fibers were mechanically cross-wound on the flow distributor to achieve equal distribution of blood flow without changing the fiber shape. The housing, made of silicone coated acryl, was 236 mm long with an inner diameter of 60 mm. The surface area was 1.0 m2 for prototype 211, and 1.1 m2 for prototype 209. The silicone fiber length was 150 mm, and the silicone membrane packing density was 43% for prototype 211 and 36% for prototype 209. Prototype 211 has a priming volume of 208 ml, and prototype 209 has a priming volume of 228 ml. The prototype 211 oxygenator demonstrates a gas transfer rate of 120 +/- 5 ml/min (mean +/- SD) for O2 and 67 +/- 12 ml/min for CO2 under 2 L of blood flow and 4 L of O2 gas flow. Prototype 209 produced the same values. The blood side pressure drop was low compared with the silicone sheet oxygenator (Avecor, 1500ECMO). These results showed that this new oxygenator for ECMO had efficiency similar to the silicone sheet oxygenator that has a 50% larger surface area. These results suggest that the new generation oxygenator using an ultrathin silicone hollow fiber possesses sufficient gas transfer performance for long-term extracorporeal lung support.  相似文献   
73.
74.
A rare case of primary pineal melanoma is reported. The patient was a 53-year-old woman who complained of a severe headache. Computed tomography and magnetic resonance images revealed obstructive hydrocephalus caused by a mass lesion in the pineal region. A biopsy was performed through an occipital transtentorial approach. A black pigmented solitary tumor was seen without leptomeningeal dissemination. Histologic examination revealed melanoma. Chemotherapy consisting of dacarbazine, ACNU, vincristine, and interferon was used. Follow-up imaging studies showed dramatic reduction of the tumor without recurrence for 4 years. This report demonstrates that a solitary primary intracranial melanoma without leptomeningeal dissemination and with rare mitoses may yield a good result with chemotherapy.  相似文献   
75.
76.
Repetition numbers of bending of Cu-0.81 wt% Cr, Cu-0.81 wt% Cr-0.14 wt% Sn and Cu-0.26 wt% Cr-0.10 wt% Sn alloys were investigated. After solution treatment, the first two types of copper alloys have a primary chromium phase; this is not so in the last alloy. The primary chromium phase does not influence the repetition numbers of bending of cold-rolled specimens; the repetition numbers of bending of specimens aged at 723 K for 1.8 × 103 sec after cold rolling are higher than those of cold-rolled specimens. The cause of this is considered to be a recovery of work-hardening during ageing.  相似文献   
77.
78.
Bistatic radar cross-section measurements by pendulum method   总被引:1,自引:0,他引:1  
In this paper, the pendulum method for measuring the bistatic radar cross section of a target is proposed, based on the principle of modulated-scattering technique. A modulated wave is formed by swinging the target like a pendulum. This method has the advantages that the measuring procedure is very simple, an absorber-coated room is not required, and the measured value is independent of background waves. Theoretical aspects of the principle are first described, including various kinds of conditions; then the measuring method is given with experimental results.  相似文献   
79.
In the two phase alloys which exhibit superplasticity, strain rate sensitivitym, in the relationship σ = m, has been known to be strongly dependent on the volume fraction of the second phase. It, however, has not been necessarily confirmed experimentally on various two phase alloys. In this paper we present an experimental evidence showing that the largestm is obtained when the volume fraction of the second phase is around 0.5.  相似文献   
80.
Expression of a functional antibody fragment (Fab) using an Escherichia coli cell-free expression system has been reported previously [Jiang et al., FEBS Lett., 514, 290-294 (2002)]. The low yield of the synthesized antibody, however, limits the usefulness of the cell-free expression system, partly due to the degradation of product by endogenous proteases from the E. coli extract. To determine which proteases are responsible for the degradation, we compared the expression of a 6D9 Fab fragment under conditions whereby several protease inhibitors were added into the cell-free system. The addition of serine protease inhibitor increased the amount of the Fab fragment, indicating that serine proteases caused the antibody degradation. Therefore, several serine protease-deficient mutants of E. coli BW25113 were constructed by targeted homologous recombination. The use of extract from a double protease-deficient mutant (DeltadegP-ompT) significantly increased the amount and antigen-binding activities of an anti-HSA scFv and a 6D9 Fab fragment. These results suggest that the DegP- and OmpT-deleted mutant is a useful source of S30 extract for the production or screening of antibodies using the cell-free expression system.  相似文献   
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