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41.
We report on the prenatal diagnosis of a case of cebocephaly, alobar holoprosencephaly, and microcephaly associated with a de novo proximal interstitial deletion of the long arm of chromosome 14: del(14)(q13q21.1) or (q13q21.2). This is the third case of holoprosencephaly in association with a deletion in this region. The present report concerns the association between prenatal craniofacial development, a holoprosencephaly locus, and the chromosomal segment 14q13.  相似文献   
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BACKGROUND AND PURPOSE: Strains of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have spread widely in Taiwan hospitals. In this study, we evaluated the in vitro antimicrobial activity of tigecycline against ESBL-producing Enterobacteriaceae, including Klebsiella pneumoniae, Serratia marcescens and Enterobacter cloacae. METHODS: 104 confirmed ESBL-producing bacteria were isolated from 4 hospitals in mid- and southern Taiwan between 2000 and 2006. The in vitro activity of tigecycline against these ESBL producers was tested by use of Etest strips. RESULTS: The minimal tigecycline concentration at which 50% of isolates were inhibited and minimal concentration at which 90% of isolates were inhibited for ESBL-producing isolates ranged from 0.38 to 0.75 mug/mL and 0.5 to 1.5 mug/mL, respectively. CONCLUSIONS: Tigecycline, a new semisynthetic glycylcycline, may be considered an alternative drug of choice for patients infected with ESBL-producing bacteria.  相似文献   
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In a human in-vitro fertilization (IVF) programme, the effect of co- culture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the study after giving informed written consent. The IVF treatments were randomly assigned by stratification of both age (<36 versus > or =36 years) and previous IVF attempts (yes versus no). After fertilization was established, the zygotes were transferred to a 4-well dish with or without fibroblasts and cultured for 2 days. On the third day after ovum pick-up (OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred. Supernumerary embryos of good quality were cryopreserved. The design of this study was a group sequential trial with the objective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibroblasts. This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of whom 77 were allocated to the co-culture group. There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two groups. The ongoing pregnancy rate per embryo transfer was 27% in co-culture and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivariate logistic regression model for the probability of ongoing pregnancies, the odds ratio of co-culture, adjusted for age and previous IVF attempts, was not statistically significant. In conclusion, co-culture with human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected group of patients.   相似文献   
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Heparin, when added to citrated platelet-rich plasma (PRP), caused potentiation of platelet aggregation and the release reaction induced by the aggregating agents adenosine diphosphate (ADP), arachidonic acid, collagen, and epinephrine. At low concentrations (4.7 x 10(-5) M) arachidonic acid failed to cause aggregation of platelets in citrated PRP. However, in the presence of heparin, the same concentration of arachidonic acid caused aggregation. Examination of PRP for the presence of thromboxane A2 (TxA2) by use of a bioassay revealed that heparin also stimulated release of TxA2. This finding indicated that platelets released more TxA2 when they were challenged by low concentrations of arachidonic acid in the presence of heparin than in its absence. Platelets were labeled with 3H-arachidonic acid and 14C-serotonin, and attempts were made to determine whether heparin stimulated the platelet release reaction first with subsequent increased production of TxA2, or alternatively, whether heparin stimulated TxA2 production first with subsequent enhancement of the release reaction. In view of the demonstrated simultaneous release of 14C-serotonin and 3H-arachidonic acid metabolites, it appeared that either release of 14C and 3H occurs concurrently or, even if one of these events is dependent on the other, both events take place in rapid succession. Timed sequential studies revealed that in the presence of arachidonic acid, the addition of heparin hastened the apparently simultaneous release of both 14C and 3H.  相似文献   
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Summary The anatomic constraints imposed on a total artificial heart (TAH) require specific anatomic studies. A thoracic anatomic study was performed with a scanning device equipped with three-dimensional (3-D) reconstruction software on 15 male patients, between the ages of 41 to 63 years (52 ± 6 years). All were candidates for heart transplantation. The 3-D reconstructions of the cardiovascular structures obtained from surgical anatomy data specific to TAH implantation allowed a volumetric measurement of these structures. A modeling diagram of these structures permitted reproducible quantitative measurements of the 35 geometrical parameters which characterized shape, orientation, and position of these structures within the thorax. Most of the measured parameters were characterized by low variability (coefficient of variation from 10 to 25%).
Modélisation tridimensionnelle de l'anatomie du cur et des gros vaisseaux
Résumé Les contraintes anatomiques imposées au cur artificiel total (CAT) nécessitent des études anatomiques spécifiques. Une étude anatomique thoracique a été réalisée avec un scanner doté d'un logiciel de reconstruction tridimensionnelle (3-D) chez 15 patients, tous de sexe masculin, agés de 41 à 63 ans (52 ± 6 ans), et candidats à une transplantation cardiaque. Les reconstructions 3-D des structures cardio-vasculaires réalisées selon les données de l'anatomie chirurgicale propre à l'implantation du CAT ont permis la mesure volumétrique de ces structures. Un schéma de modélisation de ces structures a permis des mesures quantitatives reproductibles de 35 paramètres géométriques caractéristiques de la forme, de l'orientation, de la position de ces structures dans le thorax. Les résultats de ces mesures ont pu être exprimés en termes statistiques. La plupart des paramètres mesurés étaient caractérisés par une faible variabilité (coefficients de variations de 10 à 25%).
  相似文献   
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The persistence of Cytomegalovirus (CMV) with alteration of cell surface expression in certain tissues may initiate the tissue destruction that leads to the clinical manifestations of Sjogren's Syndrome. Salivary gland and lacrimal gland ductal cells are immunologically attacked due to CMV antigenic expression. The destruction of these ducts leads to xerostomia and keratonconjunctivitis sicca, the hallmarks of Sjogren's Syndrome.  相似文献   
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Summary Three major types of HTLV-I had been proposed, the Melanesian type, the Zairian type, and the cosmopolitan type, which was further divided into subtypes A, B and C, according to the phylogenetic tree constructed from LTR sequences of current HLTV-I isolates. In this study, the envelope gene sequences of HTLV-I from 9 Taiwanese were analyzed. Based on the phylogenetic tree constructed by unweighed pair group method and the sequence homology analysis by GCG computer programs, the envelope gene sequences of HTLV-I proviruses from these 9 Taiwanese belonged to subtype A or subtype B of the cosmopolitan type and were closely related to HTLV-I from Japan. Twelve subtype-specific nucleotide variations were deduced from the comparison of complete or partial envelope gene sequences of 16 HTLV-I isolates of known subtypes as well as those of 9 Taiwanese. These data provided the basis for subtyping the cosmopolitan type of HTLV-I by amplification of envelope gene sequences and restriction fragment length polymorphism studies. A more extensive survey based upon this proposal was warranted.  相似文献   
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