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151.
The gravity model, a method for analyzing transportation distribution in transportation engineering, was used to explain patient
trips between ten health service regions in a Japanese prefecture. The OD (Origin-Destination) tables were constructed with
zoning by regions, distinguishing between out- and inpatients. The observed trips were determined from the data of a survey
conducted in 1992 that reported the locations of patient residences and chosen medical facilities.
The base values used in the model calculations were the population size of each region and the road distance between the centers
of regions. Problems of intrazonal trip were avoided by setting a mean intrazonal movement distance.
This model was calibrated by the linear regression method with simultaneous validation by the index of correlation coefficients.
The model was found to accurately simulate the effect of distance on the choice of medical facilities and the differences
between the characteristics of in- and out-patients. The population value in use showed the relation not only with demand
but also the supply of clinical services. It was suggested that the model presented here was useful in the allocation of medical
resources and would help explain the relationship between suppliers and consumers of medical services. 相似文献
152.
江苏历代医家,医籍及其地域分布研究 总被引:1,自引:0,他引:1
顾奎兴 《南京中医药大学学报》1999,15(4):233-235
整理研究了江苏自后汉至民国的二千年间,见于著录的4150名医家和3715部医著的时代和地域分布,宋以后,尤其是明清时期,江南一带社会相对安定,封建朝廷南迁,为江苏的经济文化发展提供了历史机遇、也是江苏中医发展的极盛时期。这一时期涌现的医家、医籍分别占总数的98.6%、96.8%。说明了社会的稳定进步、生产力的发展提高、经济科技的繁荣发达是医学发展的基础和源泉。 相似文献
153.
云南省盈江县蚊虫调查及乙型脑炎病毒分离 总被引:1,自引:0,他引:1
1984年及1989年7~8月,在盈江县捕获成年雌性蚊虫7属32种632O只,霜背库蚊、三带喙库蚊和棕头库蚊是农村畜圈的主要蚊种,伪白纹伊蚊和白纹伊蚊是野外竹林区的优势蚊种。对所获蚊虫用C6/36细胞和小白鼠方法分离病毒,从三带喙库蚊和窄翅伊蚊中各分离到1株乙型脑炎病毒。分析认为三带喙库蚊是当地乙型脑淡病毒的主要传播媒介,窄翅伊蚊亦可参与该病毒的传播。 相似文献
154.
目的:分析和了解玉溪地区小儿急性白血病的发病、地区分布及类型。方法:收集、整理和分析1983年4月至1998年4月间我院诊断的小儿急性白血病。结果:15年间诊断的小儿急性淋巴细胞白血病L1~2型50例,急性非淋巴细胞白血病M2~6型35例。占同期住院小儿总数的0205%,男∶女=124∶1。结论:4~9岁发病高。急淋高于急非淋,以L1型多见。高白细胞白血病占1176%(>100×109/L)。地区分布以玉溪市发病最高占3765% 相似文献
155.
Holliday MA 《Pediatric nephrology (Berlin, Germany)》1999,13(9):989-995
This review highlights characteristics of extracellular fluid (ECF) that are often overlooked. ECF has, in addition to plasma
and interstitial fluid (ISF) surrounding cells, a third large compartment, the ISF of skin and connective tissue. This acts
as a reservoir that gives up ECF to plasma volume (PV) in order to sustain circulation in the event of either shock or dehydration.
While Starling forces drive filtration, ECF is returned to PV more by lymph and less by Starling forces than previously appreciated.
Lymph return to PV is dependent on physical activity and muscle contraction to overcome gravity. Regional change in metabolic
rate alters the need for oxygen and nutrients that is met by a regional increase in capillary blood flow. Blood flow is controlled
by vasoactive compounds released in response to a drop in PO2; these relax capillary smooth muscle to increase blood flow and delivery of oxygen and nutrients. Plasma proteins, including
albumin, are filtered into the interstitium through larger pores than those filtering ECF. The rate of protein filtration
is set by size and charge of these larger endothelial pores and by size and charge of proteins. Charge of these pores, hence
albumin permeability, is regulated by many of the same vasoactive compounds that control capillary flow. As a consequence,
in response to gravitational stress and other forms of shock that reduce effective circulation, albumin as well as ECF is
rapidly shifted from plasma and sequestered in ISF. When this has occurred, as in burn shock, restoration is better effected
by generous expansion of ECF with Ringer’s solution alone, rather than with Ringer’s solution supplemented with human serum
albumin or other colloid. Restoring both PV and ISF volume restores lymph circulation and returns sequestered albumin to PV.
Received: 12 November 1998 / Revised: 30 March 1999 / Accepted: 2 April 1999 相似文献
156.
Background: The pharmacokinetic variables of drug clearance and volume of distribution are usually corrected for body weight
or surface area. Only recently have the relationships which exist between body size, physiologic function and pharmacokinetic
variables been evaluated in the obese population. These effects are not widely known, and data on this and the effects of
bariatric surgical procedures are scantily documented in the surgical literature. Methods: Literature review. Results: Drugs
with a low or moderate affinity for adipose tissue have a moderate increase in the volume of distribution (Vd), and this correlates
with the increase in lean body mass (LBM). Highly lipophilic drugs, with some exceptions, show the expected increase in Vd
and prolongation of elimination half-life, indicating a marked distribution into adipose tissue. Drug absorption, in general,
is slowed by delayed gastric emptying and is normal when gastric emptying is normal or increased. Most drug absorption occurs
in the small intestine where duration of drug/mucosal contact is the most important factor. Conclusions: Drugs whose distribution
is restricted to LBM should utilize a loading dose based on ideal body weight (IBW). For those drugs which distribute freely
into adipose tissue, the loading dose should be based on total body weight (TBW). Adjustment of the maintenance dose depends
on clearance rates. In a few cases dosage adjustment depends on pharmacodynamic data, since drug clearance does not conform
to these recommendations, for reasons which remain to be defined. Following bariatric surgery, in the absence of delayed gastric
emptying or uncontrolled diarrhea, drug absorption rates are usually comparable to the non-operated patient. 相似文献
157.
An historical prospective study of mortality within a cohort of 1,410 gas distribution workers was conducted. This cohort was followed for ten years (1971-1980) and data on 118 deaths were obtained. Five-year (1973-1977) averages of both St. Louis and United States age-specific mortality figures were used to create "expected" mortality rates for comparison with the observed deaths in the cohort. Analyses of the cohort were done according to: 1) person-years contributed during the study period (the "age-attained" method) and 2) the number of years from commencement of work in the company until the end of the study period (1980) or death (the "latency" methods of analysis, Standardized Mortality Ratios (SMRs) were calculated for all causes of death, all malignant neoplasms, and for cardiovascular disease and malignant neoplasms of the respiratory and digestive systems. In no case was the SMR found to be beyond the range of what would be expected in the "standard" populations. While the present study does not contradict the negative findings of the one previous investigation of mortality of gas distribution workers, the limitations of small cohort size, reliance on death certificates and non-industrial comparison populations make any conclusions at best provisional. 相似文献
158.
5-Ester derivatives of 5-iodo-2-deoxyuridine (IDU) with varying degrees of lipophilicity were examined to evaluate the effectiveness of lipophilic ester prodrugs for enhanced and sustained delivery of IDU to the brain parenchyma. Approximately 1.0% (1.0 ± 0.19; n = 4) of the total radioactivity was found in the brain at 30 min following intravenous administration of the lipophilic benzoyl-5-ester of 125I-labeled IDU, whereas IDU per se yielded only 0.01% (0.01 ± 0.06; n = 4). Since the IDU 5-esters generated significantly higher levels of IDU in the brain, an HPLC analysis of IDU in the presence of 5-esters and the metabolite 5-iodouracil was developed to characterize IDU uptake in the brain. The drug was detected at levels of 6.6 and 9.5 µg/g of brain tissue at 3 hr following intravenous administration of valeryl and benzoyl IDU, respectively, at a dose level of 40 mg/kg IDU equivalent each. IDU, on the other hand, when injected at a similar dose level, produced concentration levels below 0.01 µg/g of brain tissue, which was too low to be detected accurately by the HPLC assay. These results suggest that the 5-ester derivatives cross the blood-brain barrier effectively and generate significantly higher brain levels of the parent drug in the brain parenchyma. The regenerated hydrophilic drug because of its polarity is locked in the brain and is subsequently metabolized by pyrimidine phosphorylase to 5-iodouracil. A higher concentration of IDU was generated following administration of the benzoyl ester probably because the ester itself is slowly hydrolyzed by the brain cholinesterases, thereby competitively inhibiting the metabolism of IDU to 5-iodouracil by brain pyrimidine phosphorylase. 5-Benzoyl IDU appears to be a promising bioreversible analogue which can provide enhanced and sustained delivery of IDU to the brain parenchyma. 相似文献
159.
Keiichi Yamamoto M.D. Yoshiko Yamamoto Chiemi Kuwahara 《International journal of legal medicine》1979,83(4):313-317
Summary Blood cyanide concentration was determined in rabbits intoxicated orally or by inhalation. Experiments were carried out under urethane anaesthesia. In the inhalation experiments, rabbits inhaled a combustion product containing HCN via the tracheal cannula and in the oral studies animals were administered NaCN solution into the stomach. In addition to the carotid artery and jugular vein blood samples, postmortem samples were obtained from both sides of the heart and the descending vena cava.The arterial cyanide concentration in the inhalation group showed a close relationship with ventilation. After an initial rise, blood levels decreased a little, in some cases with transient apnea. At the last stage it again increased with gasping, reaching its maximal value. After ultimate apnea, the blood cyanide concentration declined. The blood cyanide values were higher in the oral group than in the inhalation group. The difference between the two groups became larger in the inferior order, the left heart blood-the right heart blood-blood in the descending vena cava. The left heart/right heart ratio of the inhalation group was significantly higher than that of the oral group (1.28 ±0.28 vs. 0.95 ±0.09). The coefficient of variation (c.v.) of the inhalation group was larger than that of the other group. Within the inhalation group, the left heart blood showed the largest c.v. values and this was probably due to redistribution of the cyanide by bloodstream after attainment of the maximal concentration.
Bestimmung der Blutzyanidkonzentration in oral oder inhalatorisch vergifteten Kaninchen
Zusammenfassung Die Blutzyanidkonzentrationen wurden an Zyanid-vergifteten Kaninchen in Urethannarkose bestimmt. Die Kaninchen inhalierten HCN-haltige Verbrennungsgase durch die Trachealkanüle. Eine andere Gruppe von Tieren erhielt NaCN-Lösung per os. Während der Versuche wurden Blutproben aus einer katheterisierten Halsarterie gewonnen. Postmortale Blutproben wurden aus beiden Ventrikeln des Herzens und der kaudalen Hohlvene entnommen.Der arterielle Blutzyanidspiegel der ersten Gruppe zeigte eine enge Beziehung mit der Ventilation auf. Nach einer Konzentrationszunahme im Anfangsstadium nahm der Blutspiegel mit einer vorübergehenden Apnoe ab. Mit der terminalen Atembewegung stiegen die Blutspiegel und erreichten ihre maximalen Werte. Die Blutzyanidwerte verminderten sich nach endgültiger Apnoe. Der Blutspiegel der per-os-Gruppe nahm stetig unabhängig von der Ventilationsgröße zu. Die inhalatorische Gruppe hatte niedrigere Zyanidwerte als die orale Gruppe.相似文献
160.