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Haemodynamic effects of propofol were studied during induction of anaesthesia, in 20 patients undergoing abdominal aortic replacement. Eight of them suffered from coronary arterial disease. Propofol was used at a dose of 2 mg X kg-1. During 5 min after propofol administration, no drug was administered. Neither plasma expansion nor tracheal intubation were carried out. Haemodynamic changes were: 17% decrease in systolic arterial pressure, and 13% decrease in diastolic arterial pressure, associated with a 12% decrease in cardiac output and 7% decrease in systemic vascular resistances; no change in heart rate in spite of the decrease in arterial pressure; and a mild increase in diastolic pulmonary arterial pressure. Left ventricular systolic work and rate pressure product decreased, suggesting a favourable incidence in coronary disease by lowering myocardial oxygen consumption. Nevertheless, it must be considered that, in the group studied, patients with coronary disease receiving beta-blocking drugs were excluded. So, mild haemodynamic changes observed here have to be confirmed in patients suffering from more severe coronary arterial disease.  相似文献   
33.
The injection of plasmid DNA encoding hepatitis B virus (HBV) envelope proteins in mouse muscle leads to the induction of specific humoral and cellular immune responses. Most studies on DNA-based immunization have used viral promoters to drive antigen expression. In this study, we compared the efficiency of a muscle-specific promoter, the human desmin gene promoter, with the commonly used cytomegalovirus (CMV) early gene promoter. We showed that increased in vitro expression of HBV envelope proteins from the human desmin gene promoter has no effect on the in vivo immune response even after the injection of as little as 10 micrograms of DNA. The injection of vectors encoding HBV envelope proteins under the control of either the human desmin gene promoter or the CMV promoter induced humoral and cytotoxic immune responses at comparable levels and of the same duration. The recruitment of antigen-presenting cells to the DNA injection site by pretreatment of muscle with a necrotizing agent increases the precocity and the intensity of the responses, particularly when the nonspecific CMV vector was used.  相似文献   
34.
Bacteriophage PM2 was isolated from the Pacific Ocean off the coast of Chile in the late 1960s. It was a new virus type, later classified as Corticoviridae, and also the first bacterial virus for which it was demonstrated that lipids are part of the virion structure. Here we report the determination and analysis of the 10, 079-bp circular dsDNA genome sequence. Noteworthy discoveries are the replication initiation system, which is related to the rolling circle mechanism described for phages such as φX174 and P2, and a 1.2-kb sequence that is similar to the maintenance region of a plasmid found in a marine Pseudoalteromonas sp. strain A28.  相似文献   
35.
K Patai  S Cs?m?r  F Paulin  L Sztanyik 《Orvosi hetilap》1991,132(47):2623-2624
The authors report on a successful conception, development of pregnancy and lasting symptom-free post-partum state of a young female patient who has been operated previously because of an hypophysis microadenoma. Delivery ended with Cesarean section. A living and mature newborn was born, with a weight of 2900 g.  相似文献   
36.
Fluorescence of hematoporphyrin derivative (HPD) has been used clinically to localize malignant neoplasms because of its selective accumulation in these tissues. We tested the hypothesis that HPD may also be selectively concentrated within atheromatous plaques. 48 h after HPD injection in a variety of species, selective fluorescence of atheromatous plaques of the aorta was seen in each animal (rabbits and Patas monkey) exhibiting such lesions. No fluorescence could be demonstrated in aortic segments free of atheromatous involvement. Since the efficacy of photodynamic destruction of malignant tumors with HPD has been demonstrated in clinical studies, the observations of the present study may have therapeutic implications in atheromatosis.  相似文献   
37.
Semantic errors in aphasic patients are frequent and their study has helped understanding the structure and processing of the lexical/semantic system. Most of the patients with semantic errors in reading and writing are English-speaking and it has been argued that this depends on the type of the orthographic systems: in opaque orthographies semantic errors are more frequent than in transparent orthographies. The paper reports the case of an Italian patient, AM, with semantic damage and semantic errors in comprehension and production tasks, except reading aloud. AM was also impaired in non-word repetition and writing but his reading of non-words was only mildly impaired. The absence of semantic errors in reading and the co-occurring absence of severe damage to the non-lexical reading route is consistent with interaction between lexical and non-lexical processing. The discussion addresses the question of the relative frequency of semantic errors in reading and writing tasks in languages with different types of orthographies.  相似文献   
38.
Objective:The impact of increased fructose consumption on carbohydrate metabolism is a topic of current interest, but determination of serum level has been hindered due to low concentration and interference from serum glucose. We are reporting a method for the quantification of glucose and fructose in clinical samples using gas chromatography/mass spectrometry (GC/MS). The accuracy and precision of GC/MS and an enzymatic assay were compared.Design and methods:Mass spectrometry fragmentation patterns of methyloxime peracetate derivatized aldose and ketose were determined. Unique fragments for glucose and fructose were used for quantitative analysis using isotope labeled recovery standards.Results:Methyloxime peracetate derivatives of glucose and fructose showed characteristic loss of acetate (M-60) or ketene (M-42) under chemical ionization (CI). Under electron impact (EI) ionization, a unique C1–C2 fragment of glucose was formed, while a C1–C3 fragment was formed from keto-hexoses. These unique fragments were used in the quantitative assay of glucose and fructose in clinical samples. In clinical samples, the GC/MS assay has a lower limit of detection than that of the enzymatic assay. In plasma samples from patients evaluated for diabetes the average serum glucose and fructose were 6.19 ± 2.72 mM and 46 ±  25.22 μM. Fructose concentrations in many of these samples were below the limit of detection of the enzymatic method.Conclusion:Derivatization of aldose and ketose monosaccharides to their respective O-methyloxime acetates for GC/MS analysis is a facile method for determination of serum/plasma glucose and fructose samples.  相似文献   
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