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101.
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
102.
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
103.
The present study examined hippocampal volume and dentate gyrus width and their relations to gonadal hormone levels in adult male and female meadow voles, Microtus pennsylvanicus. Females were split into High and Low Estradiol groups based on the median estradiol level. Males were similarly split into High and Low Testosterone groups. Contrary to previous reports in wild meadow voles, there was no evidence of an overall sex difference in hippocampal volume. However, when male-female comparisons were limited to High Testosterone males and Low Estradiol females a significant sex difference in hippocampal volume favouring males did emerge. Hippocampal volume in males was related to testosterone level, with High Testosterone males having significantly larger hippocampi than Low Testosterone males. Similarly, there was a significant influence of plasma estradiol level on hippocampal volume and left dentate gyrus width, with High Estradiol females having larger hippocampi and dentate gyrus width than Low Estradiol females. In addition, consistent with previous findings in the laboratory rat, there were sex differences favouring males in right dentate gyrus width. These findings show that there is a complex relationship between hippocampal volume, dentate gyrus width and gonadal hormone levels in male and female meadow voles. 相似文献
104.
Morphine antinociception elicited from the ventrolateral periaqueductal gray is sensitive to sex and gonadectomy differences in rats 总被引:2,自引:0,他引:2
Sex differences have been observed in antinociception following central administration of morphine into either the lateral ventricles or rostral ventromedial medulla (RVM) such that male rats exhibit significantly greater antinociception than female rats. The present study examined whether sex and adult gonadectomy differences were observed in morphine-induced (1-10 micrograms) antinociception elicited from the ventrolateral periaqueductal gray (vlPAG) on two nociceptive measures. Both sham-operated (ED50=1.20-1.60 microgram) and castrated (ED50=1.08-1.09 micrograms) male rats displayed significantly greater magnitudes and potencies of morphine-induced antinociception on both tests than female rats. Sham-operated female rats tested during the estrous phase (ED50=>50 micrograms) were significantly less sensitive to morphine than ovariectomized female rats (ED50=1.98-2. 51 micrograms). Thus, the vlPAG, a site sensitive to interactions between estradiol-containing hypothalamic loci and opioid peptides, elicits morphine-induced antinociception which is sensitive to sex differences and adult gonadectomy. 相似文献
105.
Antonio Melgarejo-Moreno José Galcerá-Tomás Arcadio García-Alberola Pascual Rodríguez-García Antonio González-Sánchez 《European journal of epidemiology》1999,15(7):621-629
Age and female gender have been associated with poor prognosis in acute myocardial infarction (AMI). Data currently available about the prognostic significance of gender in AMI might well have led to inappropriate/incomplete conclusions. A multicenter, prospective study on 1239 patients with AMI was conducted. Clinical characteristics, complications during the acute phase and one-year follow-up were monitored. Women constituted 24.1% of all patients. Female patients were older with more prevalence of diabetes, hypertension, and previous congestive heart failure. Compared with men, the following complications were more frequently found in women: heart failure, 43% vs. 22% (p<0.001); reinfarction, 5% vs. 2% (p<0.05); use of pacemaker, 7% vs. 4% (p<0.05). Women had higher mortality: early, during the first 24 hours post-admission, 10.7 vs. 3.1%; in-hospital, 23% vs. 8.1%; and 1-year, 33.7% vs. 16% (p<0.001 for all the 3 cases of mortality). In the age-groups considered (<65, 65–74, and 75 years), 1-year mortality increased exponentially with ageing in men: 7.8%, 21.3%, and 38.9%, whereas in women the figures were: 15.3%, 41.5%, and 38.8%. Multivariate analysis showed that, among other variables, age and female gender had independent prognostic value for in-hospital mortality whereas gender lost its prognostic significancy for 1-year mortality. Multivariate analysis restricted to those patients aged over 75 years showed that age but not gender had independent prognostic value. In conclusion, age and female sex have independent prognostic value for predicting mortality in patients with AMI. Mortality increases exponentially with ageing in men whereas it stabilises in the case of women over 65 years. Female gender loses its independent value for predicting mortality in patients over 75 years. 相似文献
106.
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
107.
S. Tomczak Priv.Doz.Dr. K. Baumann G. Lehnert 《International archives of occupational and environmental health》1981,48(3):283-287
Summary In a lindane (-hexachlorocyclohexane)-producing factory 54 male workers (mean age 40 years, mean duration of exposure 8 years) were studied with regard to their blood levels of testosterone, LH, and FSH. Twenty clerks of nearly the same age were examined for control purposes in the same way. Serum-LH concentrations of the exposed workers were significantly higher than in controls. Geometric mean values were 8.8 mIU/ml and 5.7 mIU/ml respectively. On the other hand, FSH levels were insignificantly higher. Concerning testosterone concentrations in serum, these were found to be slightly lower in the group of workers than in control persons but this difference could not be proved to be statistically significant.These results indicate certain perturbations in sex hormone regulation probably as a consequence of HCH-exposure. To judge the pathological significance of these alterations further investigation will be necessary. 相似文献
108.
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
109.
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
110.