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121.
蝙蝠葛碱(Dau)剂量依赖性延长麻醉家兔希氏束电图(HBE)的A-H,H-V间期,使V波增宽,并延长心房和房室结不应期。利多卡因(Lid)、对HBE各间期无明显影响,但有减弱Dau延长H-V间期的作用。异丙肾上腺素(Iso)可对抗Dau延长A-H,H-V间期及增宽V波的作用。阿托品(Atr)可缩短Dau已延长的A-H间期。提示Atr和Lid可分别改善Dau抑制的房室及希—浦系统的传导,而Iso对房室传导和室内传导均有改善作用。  相似文献   
122.
目的:合成非离子含碘造影剂的中间体5-氨基-2,4,6-三碘异酞酸。方法:以间苯二酸为原料,经硝化、还原与碘化,合成5-氨基-2,4,6-三磷异酞酸。结果:每步均经改进,总收率达50.2%,所得产品熔点、IR、^1HNMR、^13CNMR光谱数据,与文献报道一致。结论:本工艺路线方法简单,原料易得,易工业化生产。  相似文献   
123.
Benacerraf  BR; Frigoletto  FD  Jr; Greene  MF 《Radiology》1986,159(1):243-246
Twelve cases of fetal trisomy syndromes are reported in which prenatal sonographic findings were highly suggestive of the chromosomal abnormality. The abnormal appearance on the sonogram led to karyotype studies in ten fetuses and to appropriate obstetrical management. The sonographic abnormalities pertained to the extremities and face of the fetus.  相似文献   
124.
To identify in a large population cohort the clinical and biochemical characteristics of patients with diabetes at risk of foot ulceration and outcomes in those with foot ulcers. All patients with diabetes attending Baqai Institute of Diabetology and Endocrinology from January 2004 to April 2012 included in the study. Clinical, biochemical and socio‐demographic data were collected and patients were categorised into those at no risk of ulceration, at risk of ulceration and those with foot ulcer, according to the University of Texas classification. Patients with foot ulceration followed for their final outcome, that is complete healing, persisted non‐healed ulcer, lower extremity amputation, lost to follow‐up or death. A total of 18 119 patients with diabetes underwent assessment, 3576 (19·7%) patients defined as at high risk for foot ulceration and 3731 (20·6%) presented with foot ulcer. Age, male gender, hypertension, higher glycated haemoglobin (HbA1c), history of smoking and presence of neuropathy were risk factors (P < 0·000) for foot ulceration. Amputation rate in patients with foot ulceration was significantly related to severity of ulceration at presentation. Preventive foot care practices were followed by 19·02% patients. One thousand eight hundred seventy three (50·2%) patients completely healed, 293 (11%) patients underwent amputation and 397 (10·1%) patients continued to be treated in the foot clinic. All patients with diabetes should be screened for neuropathy to identify those at risk of foot ulceration, as it is the major contributory factor for foot ulceration. The final outcome of foot ulceration was determined by the severity and grade of ulcer at presentation.  相似文献   
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BackgroundThe Oxford–Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) and Public Health England (PHE) are commencing their 54th season of collaboration at a time when SARS-CoV-2 infections are likely to be cocirculating with the usual winter infections.ObjectiveThe aim of this study is to conduct surveillance of influenza and other monitored respiratory conditions and to report on vaccine uptake and effectiveness using nationally representative surveillance data extracted from primary care computerized medical records systems. We also aim to have general practices collect virology and serology specimens and to participate in trials and other interventional research.MethodsThe RCGP RSC network comprises over 1700 general practices in England and Wales. We will extract pseudonymized data twice weekly and are migrating to a system of daily extracts. First, we will collect pseudonymized, routine, coded clinical data for the surveillance of monitored and unexpected conditions; data on vaccine exposure and adverse events of interest; and data on approved research study outcomes. Second, we will provide dashboards to give general practices feedback about levels of care and data quality, as compared to other network practices. We will focus on collecting data on influenza-like illness, upper and lower respiratory tract infections, and suspected COVID-19. Third, approximately 300 practices will participate in the 2020-2021 virology and serology surveillance; this will include responsive surveillance and long-term follow-up of previous SARS-CoV-2 infections. Fourth, member practices will be able to recruit volunteer patients to trials, including early interventions to improve COVID-19 outcomes and point-of-care testing. Lastly, the legal basis for our surveillance with PHE is Regulation 3 of the Health Service (Control of Patient Information) Regulations 2002; other studies require appropriate ethical approval.ResultsThe RCGP RSC network has tripled in size; there were previously 100 virology practices and 500 practices overall in the network and we now have 322 and 1724, respectively. The Oxford–RCGP Clinical Informatics Digital Hub (ORCHID) secure networks enable the daily analysis of the extended network; currently, 1076 practices are uploaded. We are implementing a central swab distribution system for patients self-swabbing at home in addition to in-practice sampling. We have converted all our primary care coding to Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) coding. Throughout spring and summer 2020, the network has continued to collect specimens in preparation for the winter or for any second wave of COVID-19 cases. We have collected 5404 swabs and detected 623 cases of COVID-19 through extended virological sampling, and 19,341 samples have been collected for serology. This shows our preparedness for the winter season.ConclusionsThe COVID-19 pandemic has been associated with a groundswell of general practices joining our network. It has also created a permissive environment in which we have developed the capacity and capability of the national primary care surveillance systems and our unique public health institute, the RCGP and University of Oxford collaboration.  相似文献   
129.
Type 2 diabetes is a common disorder with an increased risk of macrovascular complications. Achieving adequate glycaemic control is an important aim of therapy. Thiazolidinediones, or glitazones, have been used for the treatment of diabetes for a decade. Rosiglitazone and pioglitazone are currently available, however recent concerns around cardiovascular safety have led to restrictions on their use. Initial trials showed treatments with glitazones improved glycaemic control, however long-term outcomes such as cardiovascular events were not measured. Evidence from more recent trials suggests rosiglitazone is associated with an increased risk of cardiovascular events and both glitazones are associated with higher rates of heart failure. This article discusses the evidence behind these concerns and the most recent guidance on use of thiazolidinediones in clinical practice.  相似文献   
130.
Between 10% and 25% of chronic lymphocytic leukemia (CLL) patients have episodes of autoimmune hemolytic anemia (AIHA) during the course of their disease. The anti-erythrocyte autoantibodies in most cases are polyclonal and express a different heavy chain isotype than the malignant clone, indicating that they are secreted by normal autoreactive B lymphocytes. To further investigate the pathogenesis of the AIHA in CLL, we analyzed the lg heavy (H) chain variable region genes expressed by leukemic cells from CLL patients with and without AIHA. Two VH genes were preferentially expressed by the leukemic cells in the CLL cases with AIHA and were present in 9 of the 12 investigated cases. The 51p1/DP-10 gene was expressed in 5 of these cases and was absent in the control group of 12 consecutive CLL cases without AIHA, whereas the DP-50 gene was present in 4 CLL-AIHA cases and only once in the control CLL group. A strikingly similar H-chain CDR3 region that contained a single reading frame of the DXP4 DH gene segment, and N- encoded proline at the DH/JH boundary, and a tyrosine-rich region encoded by the JH6 gene segment was observed in four CLL-AIHA cases. The preferential expression of two VH gene segments and a particular CDR3 region by the leukemic cells of patients with AIHA suggests that the antibodies produced by the CLL cells are directly involved in the pathogenesis of the hemolytic anemia.  相似文献   
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