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81.
Miguel M. Alvarez Ferrero Tom B. Vree Eleonora W J. Van Ewijk-Beneken Kolmer Tom J. J. H. Slooff 《Biopharmaceutics & drug disposition》1994,15(7):599-608
- (i) The objective was to determine the range of bone levels of cefuroxime and flucloxacillin achieved after one intravenous (IV) administration of different dosages of cefuroxime and flucloxacillin.
- (ii) Six groups of five patients participated in the study. The first three groups (A–C) received respectively 1500 mg, 1000 mg, and 500 mg cefuroxime intravenously and the second three groups (D–F) received 2000 mg, 1500 mg, and 1000 mg flucloxacillin intravenously.
- (iii) Parenteral administration of cefuroxime and flucloxacillin resulted in measurable bone concentrations in all patients.
- (iv) Large inter-individual variation in bone concentration was observed.
- (v) The bone concentrations of IV cefuroxime were higher (1500 mg, p = 0.0057; 1000 mg, p = 0.0260) than those of flucloxacillin. The bone concentrations of cefuroxime and flucloxacillin were dose dependent.
82.
Wuerz RC Swope GE Holliman CJ Vazquez-de Miguel G 《Prehospital and disaster medicine》1995,10(3):174-177
OBJECTIVES: To determine the frequency with which physician, on-line medical direction (OLMD) [direct medical control] of prehospital care results in orders, to describe the nature of these orders, and to measure OLMD time intervals. METHODS: Blinded, prospective study. SETTING: A university hospital base-station resource center. PARTICIPANTS: Ten emergency physicians, 50 advanced life support providers. INTERVENTIONS: Prehospital treatment was directed by both standing orders and OLMD physician orders. Independent observers recorded event times and the characteristics of OLMD. RESULTS: Physician orders were given in 47 (19%) of the 245 study cases, and covered a variety of interventions, including many already authorized by standing orders. Mean OLMD radio time was four minutes (245 +/- 216 seconds [sec]), and time from beginning of OLMD to hospital arrival averaged 12 minutes (718 +/- 439 sec). Mean transport time in this system was 13 minutes. CONCLUSION: Despite detailed standing orders, OLMD results in orders for clinical interventions in 19% of cases. On-line medical direction requires about four minutes of physician time per call. This constituted about one-third of the potential field treatment time interval in this system. Thus, OLMD appears to play an important role in providing quality prehospital care. 相似文献
83.
84.
A. A. Ebrahim El-Zayat Miguel A. Izquierdo G. M. Clark Daniel D. Von Hoff 《Investigational new drugs》1995,13(2):125-131
Summary In several preclinical systems, the morpholino anthracycline MX2 has greater antitumor activity than doxorubicin, is less cardiotoxic, and is effective against multidrug resistant cancer cells. We used a human tumor soft-agar cloning assay to test the cytotoxicity of MX2 against single cell suspensions from freshly obtained human tumors. Tumor cells were exposed to MX2 at 0.05 and 0.5 g/ml either for 1 hour (201 specimens; 77 [38%] assessable) or continuously (231 specimens; 91 [39%] assessable). Superior antitumor activity was observed with continuous exposure (19%in vitro response at 0.05 g/ml and 69% at 0.5 g/ml) than with 1-hour exposure (1.3% at 0.05 g/ml and 12% at 0.5 g/ml). Activity was seen against all types of cancer tested including renal (91%), melanoma (88%), ovarian (73%), breast (71%) and non-small-cell lung (67%) cancer at a MX2 concentration of 0.5 g/ml after continuous exposure. If appropriate plasma levels can be achieved in patients, MX2 could have significant clinical activity in patients with those tumors. 相似文献
85.
Access to health care is an issue that has caught the attention of health care providers, policy formulators, and policy analysts, with particular emphasis on access to primary care, which affords all people a viable portal into the health care system.This paper proposes an analytical approach to the assessment of relative primary care access status, measured as the capability to deliver basic primary care services within specific geographic civil areas, or parishes, within the state of Louisiana. An additive multiattribute utility method is employed to develop a scoring system to rank parishes according to a primary care access, or health system capability, numerical score. Routinely collected parameters are used to measure each parish's current capability to provide primary care services. These parameters include demographic, mortality, morbidity, and resource data.A group of experts was used to give weight to each parish's parameter values, resulting in a relative score for each. Thus, parishes (or other geographic areas) can be ranked according to their primary care access status. This information can then be used to allocate resources, to distribute funds for health care services, and to guide policy formulation and implementation. 相似文献
86.
Immunophenotypic and DNA content characteristics of plasma cells in multiple myeloma and monoclonal gammopathy of undetermined significance 总被引:3,自引:0,他引:3
Almeida J Orfao A Mateo G Ocqueteau M García-Sanz R Moro MJ Hernandez J Ortega F Borrego D Barez A Mejido M San Miguel JF 《Pathologie-biologie》1999,47(2):119-127
In the present paper we review the immunophenotypic characteristics of plasma cells (PC) and the PC DNA contents from multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS), and its value for the differential diagnosis between both entities. The strong reactivity for CD38 and the positivity for CD138 are the two best markers for identifying PC. Myelomatous PC display an heterogeneous phenotype consistent with the fact that the neoplastic clone is able to undergo a certain degree of differentiation. In addition, PC from MM patients usually lack surface expression of B-cell associated antigens and frequently display reactivity for markers which are not restricted to the B-cell lineage. In MGUS patients, two clearly defined and distinct PC subpopulations can be identified. One of these PC subpopulations shows phenotypic characteristics identical to those of normal PC, including a very strong reactivity for the CD38 antigen, intermediate/low light scatter characteristics and positivity for CD19, in the absence of CD56, and corresponds to the residual normal bone marrow PC. The second PC subpopulation shows an immunophenotype similar to that of myelomatous PC, characterized by a slightly lower reactivity for CD38 and strong CD56 expression, on the absence of positivity for CD19, these PC corresponding to the clonal counterpart. Using a simultaneous staining for PC and DNA, around 60% of MM and 73% of MGUS patients display DNA aneuploidy, the majority of them being hyperdiploid. However, in contrast to MM patients, in MGUS patients two clearly different PC subsets can be discriminated in most cases (73%): a diploid and an aneuploid (hyperdiploid) subset, corresponding to normal and clonal PC, respectively. Upon comparing hyperdiploid with diploid patients in MM, the former display a better prognosis, in line with the higher incidence of DNA hyperdiploidy in MGUS. A clear correlation between the percentage of S-phase PC and several prognosis features of MM has been found. In spite of these findings, no significant differences in the percentage of pathological S-phase PC are detected between MM and MGUS patients. Regarding the differential diagnosis between MGUS and MM, multivariate analysis shows that the ratio between the number of clonal and normal residual PC is the best single parameter. 相似文献
87.
88.
Amelia Rodríguez Martín José Manuel Martínez Nieto Miguel Angel Ruiz Jiménez José Pedro Novalbos Ruiz M. Carmen Díaz Vázquez Yamin Chocrón Fernández Miguel Angel Rendón Gómez Carmen Cano Fernández 《European journal of epidemiology》1999,15(7):643-648
In recent years, eating disorders (Anorexia and Bulimia Nervosa) have increased and are appearing at increasingly younger ages. They affect predominantly adolescent females 12 to 25 years of age. The objective of this study of adolescents is to detect and discuss unhealthy eating behaviour, defined by either of two factors: (1) following a slimming diet not advised or supervised by any person trained in health care; or (2) eating very large quantities at irregular times, not related to anxiety or stress. A transversal study has been undertaken of 630 school children of 14–18 years of age (average: 15.9 years) in Cádiz (Andalucia, Spain), using an anonymous self-reporting questionnaire to collect data on personal and educational situation, on eating habits, on nutritive intake and knowledge of nutrition, and on dieting and physical exercise. The study has considered averages, ratios, statistical significance (x
2) and, as a measure of risk, the Disequality Ratio of Prevalence (DRP). Anomalous eating behaviour was detected in 46.3% (292), with females predominant by a ratio of 2:1. Comparing groups with anomalous and with normal eating habits, significant differences were detected in respect of: perception of body image (p<0.001), frequency of weighing oneself (p<0.05), periods of abstinence from eating (DRP 1.66; 95% confidence interval (CI): 1.66–2.37), provocation of vomiting (DRP 2.02; 95% CI: 1.13–3.65), use of laxatives (DRP 4.25; 95% CI: 1.08–9.63), and the exclusion of certain meals and types of food, mainly bread and cereals, fats and sugars. Conclusions are drawn on the substantial scale of unhealthy eating behaviour among adolescents in Cadiz. More adequate education on personal health and related social issues should be provided. 相似文献
89.
Jose L. Ortiz José M. Vallés Miguel Martí-Cabrera Julio Cortijo Esteban J. Morcillo 《Naunyn-Schmiedeberg's archives of pharmacology》1996,353(2):200-206
There is currently interest in the potential use of selective inhibitors of cyclic nucleotide phosphodiesterases (PDE) in the treatment of asthma. In this study we examined the effects of three selective PDE inhibitors, milrinone (PDE III), rolipram (PDE IV) and zaprinast (PDE V), on the broncoconstriction produced by antigen and histamine, the airway hyperreactivity and microvascular leakage after aerosol exposure to platelet-activating factor (PAF) and antigen, and the antigen-induced eosinophil infiltration in guinea-pig lung. Inhaled rolipram (0.01–10 mg ml–1) inhibited dose dependently the bronchospasm produced by aerosol antigen (5 mg ml–1) an anaesthetised, ventilated guinea-pigs. Rolipram (10 mg ml–1) produced maximal inhibition of antigen-induced bronchoconstriction but only partial inhibition of the response to aerosol histamine (1 mg ml–1). Milrinone and zaprinast (each 10 mg ml–1) showed weak, or no, inhibitory effects against bronchoconstriction produced by aerosol antigen or histamine. Pretreatment with rolipram (10 mg kg–1, i.p.) prevented airway hyperreactivity to histamine which develops 24 h after exposure of conscious guinea-pigs to aerosol PAF (500 g ml–1) or antigen (5 mg ml–1). The pulmonary eosinophil infiltration obtained with 24 h of antigen-exposure was inhibited by rolipram. In contrast, milrinone and zaprinast (each 10 mg kg–1, i.p.) failed to reduce either the airway hyperreactivity of the eosinophil accumulation in these animals. Rolipram (1–10 mg ml–1) reduced the extravasation of Evans blue after aerosol PAF (500 g ml–1) at all airway levels while a lower dose (0.1 mg ml–1) was only effective at intrapulmonary airways. Rolipram (0.01–1 mg ml–1) markedly reduced airway extravasation produced by inhaled antigen (5 mg ml–1). Zaprinast (1–10 mg ml–1) was also effective against airway microvascular leakage produced by aerosol PAF or antigen while milrinone (10 mg ml–1) had no antiexudative effect. These data support previous suggestions that pharmacological inhibition of PDE IV results in anti-spasmogenic and anti-inflammatory effects in the airways and may be useful in the treatment of asthma. 相似文献
90.
Sodium nitroprusside (NPS) is a potent vasodilator which is frequently administered for the control of arterial blood pressure and peripheral resistances. Manual regulation of the dose is difficult and requires a permanent surveillance of patients under treatment. Several attempts have been made to develop an automatized system able to safely control the dose of the drug in clinical practice. However, since now the results have not been completely satisfactory. The aim of our study was to develop of a new automatic-adaptative system able to continuously control the dose of NPS. The system consists of a high precision infusion pump controlled by a microprocessor. Arterial blood pressure is continuously monitorized and according to its values NPS is automatically regulated to maintain blood pressure within a preselected range. A control "fuzzy logic" algorithm was used. We have assessed the efficacy, adaptability, and safeness of the system. The system was tested in 15 mongrel dogs. The protocol was divided into two parts. During the first part a 25% to 30% reduction in blood pressure from baseline values lasting for a period of 4 hours was attempted. The second part was devoted to test the adaptability of the control unit during induced unstable hemodynamic situations. Group I dogs were subjected to volume overload. Group II were treated with noradrenaline to increase blood pressure, and group III underwent a venous bleeding to produce arterial hypotension. Control of arterial blood pressure was achieved after a minimum of 5 min and a maximum of 19 min (mean values = 13.3 min).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献