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排序方式: 共有460条查询结果,搜索用时 31 毫秒
1.
Provocation of Atrial Fibrillation Triggers During Ablation: Does the Use of General Anesthesia Affect Inducibility?
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2.
Placental malaria. I. Pathological classification 总被引:10,自引:0,他引:10
Pregnant women are more likely to contract malaria than their non-pregnant counterparts. The aim of this study was to develop a simple classification system for the histopathological diagnosis of placental malaria infection applicable to placentas collected in field conditions. The placentas were classified into four groups depending on the presence and disribution of parasites and malaria pigment: active infection, active-chronic infection, past-chronic infection, not infected. The frequency of parasitized placentas (26.4%) was in keeping with the prevalence of placental parasitaemia documented in epidemiological studies. An additional 29.8% placentas showed pigment in fibrin only, indicating pastchronic infection. Chronic placental malaria infection was most common in primigravidae, possibly reflecting ineffective clearance of parasites from the placenta. Seasonal fluctuations between infection categories support progression of placental infection with delayed clearance of pigment from fibrin. The proposed classification system has allowed diagnosis of different categories of placental malaria infection by two independent observers. A stadardized method of diagnosis may enhance understanding of placental pathology and reduced birth weight in malaria infection during pregnancy. 相似文献
3.
N-Alkoxycarbonylaminodicarboxylic acids were reacted in dichloromethane with N-ethyl-N′-(dimethylaminopropyl)carbodiimide hydrochloride, and with methyl chloroformate in the presence of N-methylmorpholine. Removal of secondary products by washing the mixtures with aqueous solutions gave good yields of the pure crystalline internal anhydrides. Anhydrides of N-benzyloxycarbonyl- (Z) and N-9-fluorenylmethoxycarbonyl-(Fmoc) L-glutamic and L-aspartic acids and of N-tert.-butoxycarbonyl-L-aspartic acid were prepared in this way. The compounds were shown to be amenable to normal phase high-performance liquid chromatography (NP-HPLC) on a CN-column using tert.-butanol-hexane as solvent. The products of the reactions of Z- and Fmoc-glutamic acid with hot acetic anhydride were examined by nuclear magnetic resonance and NP-HPLC before and after methanolysis in an attempt to establish if any of the corresponding pyroglutamates were formed. The reaction of Fmoc-chloride with Fmoc-glutamate was examined for the same reason. It is concluded that the side product generated during the reaction of Fmoc-chloride with glutamic acid which is used for analysis of the latter is the N-protected internal anhydride and not the pyroglutamate as reported in the literature. 相似文献
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Jubail on the shores of the Gulf in Saudi Arabia was selectedby the Saudi Government in 1973 as one of the two locationsfor the development of hydrocarbon-based and energy-intensiveprimary industries using natural gas to fuel these industrialcomplexes. Health services for a growing indigenous and mixed expatriatepopulation were carefully planned and implemented. Four majorareas of concern were identified and these included fire andexplosion, heat stress, and exposure to noise and to chemicalsubstances. The occupational health services provided free to users area unique experiment in a mammoth self-contained industrial environment.
Group Captain F. X. Grima, RAF Institute of Community and Occupational Medicine Halton, Aylesbury, Bucks HP22 5PG. 相似文献
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Summary. Severe haemophilic arthropathy of the elbow is a significant cause of morbidity among adults with haemophilia. However, previous reports of total elbow arthroplasty (TEA) in the haemophilic population have been based on small numbers of patients with relatively short‐term follow‐up. The records of seven total elbow arthroplasties in six adult men with haemophilia at the University of California, San Francisco who underwent TEA over a period of 25 years were retrospectively reviewed. Type of haemophilia, age at time of TEA, HIV infection status, pre‐ and postoperative range‐of‐motion (ROM) scores, complications (including infections), need for subsequent surgical revision and functional outcomes were recorded. Four patients had severe factor VIII deficiency and two patients had severe factor IX deficiency. None of the patients had an inhibitor. The mean age at the time of surgery was 34 years (range, 22–46 years) and the mean follow‐up period was 118 months (range, 37–176 months). One of the six patients had TEA in both elbows. Five of the six patients were infected with HIV. There were no immediate perioperative complications. At a mean of 19.2 months postoperatively, ROM had improved in five of seven TEAs: mean flexion had increased from 110.7° (SD = 15.0) to 120.1° (SD = 14.5), whereas mean preoperative extension increased from ?44.3° (SD = 21.5) to ?36.9° (SD = 27.0). One patient required a revision at 30 months because of ulnar component loosening. This same patient sustained a staph epidermidis infection and ultimate removal of the prosthesis 15 years postoperatively. At a mean of 118 months postoperatively, five of six patients continued to report reduced pain and preserved functionality, with ability to perform normal daily activities. TEA resulted in favourable results in six of seven procedures. Our findings support the viability of TEA for individuals with severe haemophilic arthropathy of the elbow, especially to reduce pain and preserve or restore functionality. Level of evidence . Level IV. 相似文献
9.
Ventricular Tachycardia/Ventricular Fibrillation Ablation in the Setting of Ischemic Heart Disease 总被引:1,自引:0,他引:1
FRANCIS MARCHLINSKI M.D. FERMIN GARCIA M.D. AMIR SIADATAN M.D. WILLIAM SAUER M.D. STUART BELDNER M.D. ERICA ZADO P.A.-C. HENRY HSIA M.D. DAVID LIN M.D. JOSHUA COOPER M.D. RALPH VERDINO M.D. EDWARD GERSTENFELD M.D. SANJAY DIXIT M.D. REA RUSSO M.D. DAVID CALLANS M.D. 《Journal of cardiovascular electrophysiology》2005,16(S1):S59-S70
Recurrent ventricular tachycardia (VT) in the setting of coronary artery disease is frequently a life-threatening electrophysiologic emergency. Even in patients with an implantable defibrillator, recurrent VT is frequently accompanied by repeated and disabling shock therapy. Catheter ablative therapy offers the ability to provide immediate control of recurrent VT. Long-term elimination of VT should be anticipated in most patients. This article reviews the strategies, tools, techniques, and expected outcome for catheter ablation of stable and unstable ventricular arrhythmias in the setting ischemic heart disease. 相似文献