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971.
972.
There is little information on the possible value of screening children who are liable to haemoglobinopathies as part of pre-operative assessment for dental treatment under general anaesthesia. The present retrospective investigation examined, first, the number of patients having low haemoglobin levels among 1000 patients who had undergone haematological investigation prior to general anaesthesia in a dental outpatient unit, and, secondly, the subsequent clinical management of these patients. Haemoglobin levels of 10.0 g/dl or less were found in 31 children: 13 Asian, 7 Afro-Caribbean, 5 Mediterranean, 3 Arabic, 1 white Caucasian and 2 Oriental children. In addition, 17 patients had sickle-cell trait and 2 had beta-thalassaemia trait, but there was no relationship between the presence of haemoglobinopathy and low levels of haemoglobin. The planned general anaesthesia was undertaken for 22 of the 31 children who had low levels of haemoglobin and for the 19 children with haemoglobinopathy. Only 6 children ultimately did not undergo general anaesthesia, all failing to return. It is concluded that pre-anaesthetic haematological assessment of children needing minor dental surgery is rarely of any significant clinical value.  相似文献   
973.
OBJECTIVES: Antral gastritis is frequent in alcoholics. The role of H. pylori in the pathogenesis of gastritis in these patients is not well known. The aim of our study was to study the role of H. pylori and cirrhosis in the pathogenesis of antral gastritis in alcoholic patients. METHODS: Seventy-nine patients were included in the study. All underwent upper gastrointestinal tract endoscopy with antral biopsies, independently of the presence of abdominal pain, and had serological examination for H. pylori antibodies. RESULTS: Cirrhosis and gastritis were present in 50 and 40 patients respectively, H. pylori serological assay and histological identification of the bacterium were positive in 35 (44%) and 19 (24%) patients respectively. Discrepancy between the 2 tests were observed more frequently in cirrhotic patients. A positive serology with a negative histologic examination for H. pylori was present for 18 cirrhotic and 4 noncirrhotic patients (p < 0.05). A gastritis without evidence of H. pylori was more frequent in cirrhotic than in noncirrhotic patients. H. pylori was histologically present in 11 of 29 cirrhotic patients and in 8 of the 11 noncirrhotic patients with a gastritis (p < 0.05). CONCLUSIONS: Discrepancies between histological examination and H. pylori serology in patients with cirrhosis might be due to the inhospitable environment for H. pylori in case of portal hypertension; the positive serology could be in relation with a past infection.  相似文献   
974.
High-speed multiplexers, demultiplexers, frequency dividers, mixers, and amplifiers are key electronic components in high-speed fiber-optic communications systems such as SONET/SDH. In this paper, we present several important digital and analog integrated circuits (IC) which have been developed for use in SONET/SDH 10 Gb/s optical communication links. The circuits have been fabricated in MOSAIC 5E, an advanced silicon bipolar technology (fT=26 GHz). The resulting chipset which amounts to a total of 10 IC's consists of multiplexers, demultiplexers, a regenerative frequency divider (2:1), a dual output limiting amplifier, and two different types of mixers for clock extraction. Specifically, the design and performance of these IC's and a hybrid clock recovery module are discussed. The high performance and potential low cost of this research chipset show that advanced silicon bipolar circuit technology can play an important role in future multigigabit fiber-optic communication systems  相似文献   
975.
Sera from 4 out of 19 patients with the Japanese spotted fever were negative to OX2 antigen of Weil-Felix (WF) test. These WF test negative sera were analyzed by ELISA and immunoblot used whole cells and lipopolysaccharides (LPS) of rickettsiae and Proteus strains as antigens. These acute-phase sera have already possessed the IgG antibodies against LPS of Proteus OX2 strain, whereas IgM antibodies in these acute- and convalescent-phase sera did not react with this LPS. On the other hand, the reactivity of IgM antibodies of the convalescent-phase sera in the 2 patients with LPS of Proteus OX19 strain increased as compared with that of the acute-phase sera by ELISA, and these IgM antibodies also showed the reactivity with bands of OX19-LPS in the immunoblot. On the basis of these results, it is interpreted that the WF test negative sera from patients with Japanese spotted fever are due to the presence of IgG antibodies against OX2-LPS in the sera.  相似文献   
976.
977.
Subarachnoid haemorrhage (SAH) often leads to subarachnoid fibrosis and resultant normal pressure hydrocephalus; however, how subarachnoid fibrosis occurs is unknown. We examined the changes within arachnoid granulations (AGs) and the subarachnoid space (SAS) chronologically at the parasagittal region obtained from patients with SAH at autopsy and made comparison with controls by immunostaining for cytokeratin, specific marker for leptomeningeal cells and by the elastica Masson-Goldner methods. Within a week some AGs were torn, and many inflammatory cells filled the AGs and SAS. Cytokeratin positive cells were scarce. During the next two weeks cytokeratin positive cells increased. After three weeks, AGs and SAS were filled by dense deposits of extracellular matrices surrounded by multiple layers of leptomeningeal cells.  相似文献   
978.
979.
Nine children of the ALL-REZ BFM 87 and 90 trial received L-Asparginase (L-ASP) as a continuous infusion for 48-72 hs (i.e. 25 therapy cycles). Seven patients had had an allergic reaction towards an i.m. application (i.m., 29 therapy cycles). Two further patients got L-ASP initially as continuous infusion. The i.m. applications were carried out 19 times with Erwinia and 10 times with E. coli-Asparaginase, the continuous infusions 15 times with Erwinia and 10 times with E. coli-Asparaginase. In case of four patients continuous infusions of the same L-ASP type (E. coli or Erwinia) was well tolerated, after there had been an allergic reaction after i.m. application. Allergic reactions after i.m. application occurred during 10 courses as local painful erythema, during five courses as urticaria, during four courses as a general exanthema during one course as difficult breathing and during a further course as drop in blood pressure. After continuous infusion of L-ASP urticaria and difficult breathing occurred once and a transient exanthema two times. There was no anaphylactic reaction in any case. These data show that i.m. application of L-ASP causes no life-threatening side effects but allergic reactions (local pain and swelling) which clearly impaired general condition. Continuous infusion is a pharmacologically equivalent alternative with less impairment of the patients' general condition.  相似文献   
980.
High performance enhancement mode InP MISFET's have been successfully fabricated by using the sulfide passivation for lower interface states and with photo-CVD grown P3N5 film used as gate insulator. The MISFET's thus fabricated exhibited exhibited pinch-off behavior with essentially no hysteresis. Furthermore the device showed a superior stability of drain current. Specifically under the gate bias of 2 V for 104 seconds the room temperature drain current was shown to reduce from the initial value merely by 2.9% at the drain voltage of 4 V. The effective electron mobility and extrinsic transconductance are found to be about 2300 cm 2/V·s and 2.7 mS/mm, respectively. The capacitance-voltage characteristics of the sulfide passivated InP MIS diodes show little hysteresis and the minimum density of interface trap states as low as 2.6×1014/cm2 eV has been attained  相似文献   
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