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The present study was aimed at examining differences in gestational diabetes mellitus (GDM) between two ethnic populations (immigrant Asians and indigenous White Caucasians) residing in Leicester, U.K. The study was divided into two parts: to determine the prevalence of GDM and to determine the level at which glycaemia may impose a risk to the mother and the foetus. Of a total of 12,005 pregnancies (4561 Asian and 7444 White Caucasian), over a 3-year period, 314 (6.8%) Asian and 504 (6.7%) White Caucasian were given a 75-g oral glucose tolerance test (OGTT) at 28-32 weeks for indications of 'large for date' pregnancies, hydramnios, glycosuria, a history of previous abortions, stillbirths, congenital abnormalities or glucose intolerance, and family history of diabetes. Abnormal glucose tolerance (AGT) was taken as a 2-h venous plasma glucose greater than or equal to 7.8 mmol/l which reverted to normal when formally tested during the puerperium (WHO criteria, 1985). AGT was found in 1.38% Asian and 0.87% White Caucasian pregnancies (P less than 0.01). This was further divided into impaired glucose tolerance (IGT) (2-h value 7.8-11.1 mmol/l) and gestational diabetes mellitus (GDM) (2-h value greater than or equal to 11.1 mmol/l). IGT was found in 1.2% Asian and 0.84% White Caucasian pregnancies (P less than 0.01), and GDM in 0.18% and 0.02% respectively (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Okamoto  S; Olson  AC; Berdel  WE; Vogler  WR 《Blood》1988,72(5):1777-1783
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.  相似文献   
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This review summarises updated clinical guidelines produced by the Clinical Standards Committee of the Faculty of Dental Surgery, Royal College of Surgeons of England (FDSRCS). This guideline on the management of the palatally ectopic maxillary canine illustrates the information contained in the recently updated online version. The timely recognition of ectopic canines is important for the overall management of the dentition. This review illustrates five management strategies for ectopic permanent canines: interceptive treatment by extraction of the deciduous canine, surgical exposure and orthodontic alignment, surgical removal of the palatally ectopic permanent canine, auto-transplantation and no active treatment/leave and observe. The current available evidence for each of these management options has been evaluated and awarded a grade used by the Scottish Intercollegiate Guidelines Network.  相似文献   
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The mechanisms that underlie the selection of an inhibitory GABAergic axon's postsynaptic targets and the formation of the first contacts are currently unknown. To determine whether expression of GABAA receptors (GABAARs) themselves – the essential functional postsynaptic components of GABAergic synapses – can be sufficient to initiate formation of synaptic contacts, a novel co‐culture system was devised. In this system, the presynaptic GABAergic axons originated from embryonic rat basal ganglia medium spiny neurones, whereas their most prevalent postsynaptic targets, i.e. α1/β2/γ2‐GABAARs, were expressed constitutively in a stably transfected human embryonic kidney 293 (HEK293) cell line. The first synapse‐like contacts in these co‐cultures were detected by colocalization of presynaptic and postsynaptic markers within 2 h. The number of contacts reached a plateau at 24 h. These contacts were stable, as assessed by live cell imaging; they were active, as determined by uptake of a fluorescently labelled synaptotagmin vesicle‐luminal domain‐specific antibody; and they supported spontaneous and action potential‐driven postsynaptic GABAergic currents. Ultrastructural analysis confirmed the presence of characteristics typical of active synapses. Synapse formation was not observed with control or N‐methyl‐d ‐aspartate receptor‐expressing HEK293 cells. A prominent increase in synapse formation and strength was observed when neuroligin‐2 was co‐expressed with GABAARs, suggesting a cooperative relationship between these proteins. Thus, in addition to fulfilling an essential functional role, postsynaptic GABAARs can promote the adhesion of inhibitory axons and the development of functional synapses.  相似文献   
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Church  WR; Messier  TL; Tucker  MM; Mann  KG 《Blood》1988,72(6):1911-1921
A monoclonal antibody (designated alpha BFX-2b) prepared against bovine factor X inhibited factor X activity in human, bovine, porcine, rabbit, and canine plasma. In assays using purified prothrombinase components, factor Xa, factor Va, phospholipid vesicles, and calcium ion with the fluorescent active site thrombin inhibitor dansylarginyl-N-(3-ethyl-1,5- pentanediyl)amide, the antibody inhibited the conversion of prothrombin to thrombin. Antibody alpha BFX-2b also blocked prothrombinase cleavage of the macromolecular substrates prethrombin 1 and prethrombin 2 but did not inhibit factor Xa hydrolysis of the synthetic substrate benzoyl- Ile-Glu-Gly-Arg-p-nitroanilide. The antibody also prevented the inactivation of factor Xa by antithrombin III but did not prevent the inactivation by soybean trypsin inhibitor. Antibody alpha BFX-2b bound factor Xa with a stoichiometry of 1:1 and an apparent dissociation constant of 9.0 x 10(-11) mol/L as estimated from its inhibition of prothrombinase activity. Antibody alpha BFX-2b did not prevent binding of factor Xa to factor Va-phospholipid as measured by using fluorescence polarization or high-pressure liquid gel chromatography with the fluorescent Factor Xa analogue dansyl-glutamyl-glycyl-arginyl- Xa. Immunoblotting of factor X following electrophoresis on sodium dodecyl sulphate-polyacrylamide gels and transfer to nitrocellulose indicated that the antigenic determinant recognized by antibody alpha BFX-2b was found on the heavy chain of factors X and Xa. From these observations it can be concluded that antibody alpha BFX-2b recognizes a highly conserved epitope on the factor X heavy chain that is remote from the topographic sites required for prothrombinase complex assembly and substrate hydrolysis but may be located at or near a portion of the macromolecular substrate binding site.  相似文献   
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