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991.
Parvinder Kaur 《Biometrical journal. Biometrische Zeitschrift》1985,27(1):101-105
When stratified random sampling is used for the estimation of population mean, use of ‘Combined ratio estimator’ is well known. Some improved estimators for population mean are proposed which are better than ‘Combined ratio estimator’ and some other well known existing ones, from the point of view of bias and mean square error. An empirical illustration is given. 相似文献
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Vladimir D. Savitsky Ludmila G. Bezus'ko Natalia G. Butich Zoya M. Tsymbaliuk Olena V. Savitska Timur V. Bezus'ko 《Aerobiologia》1996,12(1):209-211
This article presents the results of aeropalynological observations in Kiev, carried out with a gravimetric method, during January–October, 1994. The six most abundant pollen types were: Betulaceae (21%), Chenopodiaceae/Amaranthaceae (10%), Ambrosia (10%), Artemisia (9%) Pinaceae (8%) and Poaceae (6%). Seasonal fluctuations of the atmospheric presence of tree/shrub and herb/grass pollen during the period March–September, 1993 and 1994, are also shown. 相似文献
994.
A number of rapid sampling devices for metabolic engineering applications have been developed over the last years with the purpose of the estimation of in vivo metabolic concentrations and dynamics. This review outlines the designs and characteristics as well as the developments and changes in diverse approaches over the years. Primary performance parameters for these constructions are sampling time and rate and, for an accurate representation of the in vivo condition in cells, the reproducibility of results and easy handling throughout the sampling operation. 相似文献
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Mohammad Farahmand Somayeh Shatizadeh Malekshahi Mohammad Reza Jabbari Mohammad Shayestehpour 《Microbiology and immunology》2021,65(1):1-9
Human parainfluenza virus (HPIV) infection is associated with every kind of respiratory tract illnesses, including the common cold, laryngotracheobronchitis (i.e. croup), tracheobronchitis, bronchiolitis, and pneumonia, in both children and adults. Although HPIVs are common respiratory pathogens, there are increasing reports about extrapulmonary manifestations of HPIVs infection. Each of the HPIVs could produce infection of other organs (central nervous system, heart, myocardium, etc.) in all age groups who are either immunocompetent or immunocompromised. This review aimed at summarizing the available data on clinical manifestations of HPIV infection outside the respiratory tract from 1961 to 2020. The findings support the possibility of extrapulmonary infections that were thought to be due to rare host genetic or immunologic defects in infected patients. These findings highlight the fact that extrapulmonary dissemination of HPIV can occur, but the association is not clearly demonstrated. Our data support the hypothesis that HPIV infection is one of the possible causes of these alterations and may even be the direct cause in some cases. 相似文献
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