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81.
We studied seed germination and seedling growth of the Mexican sunflower Tithonia diversifolia in Nigeria. This involved the usage of some dormancy-releasing methods and the effect of some concentrations of three herbicide formulations on the young seedlings. Initial germination tests on fresh and stored seeds revealed a low percentage germination of less than 30%. The seeds of the weed exhibit dormancy. Subjecting the seeds to wet heat at 80 and 100 degrees C and light treatment terminated dormancy both in the fresh and stored seeds. Light greatly enhanced the germination percentage of seeds by about 70%. There was gradual increase in germination percentage with increase in storage period in dormancy-released seeds. The mean LAR (Leaf Area Ratio), NAR (Net Assimilation Rate) and RGR (Relative Growth Rate) are comparatively high in young seedlings. Concentrations of 0.5-2.0% of Gramoxone, Primextra and Galex are toxic to 1 month old seedlings. For eradication, the seedlings should be attacked at one month stage. 相似文献
82.
Kehinde Sola Akinlade Adedeji David Atere John Ayodele Olaniyi Sheu Kadiri Rahamon Christiana Odunayo Adewale 《PloS one》2013,8(11)
Objective
This study assessed the diagnostic performance and prognostic properties of C-reactive protein (CRP), copeptin and cortisol in individuals with sickle cell anaemia (SCA).Design
Prospective case-control studyMethods
Sixty consecutive SCA subjects (18–40 years) comprising 30 subjects in the steady state and 30 subjects in vaso-occlusive crisis (VOC) were recruited into this study. Thirty (30) apparently healthy individuals with HbAA genotype served as controls. ELISA was used for the determination of serum levels of copeptin, CRP and cortisol. Data obtained were statistically analyzed using the Student’s t-test and Mann Whitney U as appropriate and P<0.05 was considered significant.Results
SCA subjects in VOC had significantly lower copeptin level and significantly higher CRP level compared with controls. However, serum levels of copeptin, cortisol and CRP were significantly higher in SCA subjects in VOC compared with SCA subjects in steady state. Furthermore, CRP had the widest Area under the ROC curve (AUROC) than copeptin and cortisol. No significant difference was observed in the levels of copeptin, CRP and cortisol when SCA subjects in VOC who were hospitalized for less ≤5 days were compared with subjects who had longer stays.Conclusion
It could be concluded that C-reactive protein has a superior diagnostic performance for vaso-occlusive crisis in individuals with sickle cell anaemia and that C-reactive protein, cortisol and copeptin are not good prognostic markers in SCA subjects in vaso-occlusive crisis. 相似文献83.
84.
85.
Mand S Marfo-Debrekyei Y Debrah A Buettner M Batsa L Pfarr K Adjei O Hoerauf A 《Filaria journal》2005,4(1):1-11
BACKGROUND: Ultrasonography (USG) is known to be a suitable tool for diagnosis in lymphatic filariasis as the adult filarial nematode Wuchereria bancrofti in scrotal lymphatic vessels of infected men can be detected by the characteristic pattern of movement, the Filaria Dance Sign. In onchocerciasis, moving adult worms have not yet been demonstrated by USG. In addition the verification of drug effects on living adult Onchocerca volvulus filariae in trials is hampered by the lack of tools for longitudinal observation of alterations induced by potentially macrofilaricidal drugs in vivo. The present study was carried out to determine the frequency of detection of moving adult filariae of O. volvulus by USG. METHODS: In an endemic region for onchocerciasis in Ghana, 61 patients infected with onchocerciasis were recruited by palpation and onchocercomas examined by USG using an ultrasound system equipped with a 7.5 - 10 MHz linear transducer. Onchocercomas were recorded on videotape and evaluated with regard to location, number and size, as well as to movements of adult filariae. RESULTS: In the 61 patients 303 onchocercomas were found by palpation and 401 onchocercomas were detected by USG. In 18 out of 61 patients (29.5%), altogether 22 nodules with moving adult O. volvulus filariae were detected and are presented in animated ultrasound images as mp-4 videos. CONCLUSION: Ultrasonographical examinations of onchocercomas where living adult filariae can be displayed may serve as a new tool for the longitudinal observation in vivo of patients with onchocerciasis undergoing treatment and as an adjunct to histological evaluation. 相似文献
86.
Studies were carried out on the cultivability of Lentinus subnudus on woodlogs of various hardwood trees and the effect of chemical treatments of these woodlogs with citric, tartaric, indole-3-acetic (IAA) and gibberellic (GA3) acids on fruitbody production and yield. Of the four hardwood species of Chlorophora excelsa, Terminalia ivorensis, Terminalia superba and Spondias mombin tried, woodlogs of C. excelsa were the best in supporting L. subnudus fructification, followed by those of S. mombin. On the effect of chemical treatments of C. excelsa and S. mombin woodlogs on L. subnudus' fruitbody production and yield, bed logs treated with 50 ppm indole-3-acetic and gibberellic acids were the best in enhancing fructification and yield with C. excelsa GA3 and IAA treated bed logs consistently producing more fruitbodies and greater yields than S. mombin bed logs given the same treatments. The implication of these findings in relation to results obtained in previous studies are discussed. 相似文献
87.
Background
The complexity of mitochondrial complex I (CI; NADH:ubiquinone oxidoreductase) has increased considerably relative to the homologous complex in bacteria. Comparative analyses of CI composition in animals, fungi and land plants/green algae suggest that novel components of mitochondrial CI include a set of 18 proteins common to all eukaryotes and a variable number of lineage-specific subunits. In plants and green algae, several purportedly plant-specific proteins homologous to γ-type carbonic anhydrases (γCA) have been identified as components of CI. However, relatively little is known about CI composition in the unicellular protists, the characterizations of which are essential to our understanding of CI evolution. 相似文献88.
The embryonic cytodifferentiation of Clitumnus midgut occurs very late when compared to that of other tissues in the embryo. It proceeds from hemolymph towards the yolk, first at the level of the muscular–connective tissue sheath, by the appearance of myofilaments in external–then internal–muscle fibers. In the gut epithelium, cytodifferentiation begins with the appearance of infoldings of the basal membranes of the cells. Then, microvilli and continuous junctions form at the apices of the cells. Microvilli appear in crypts, which seem to represent localized dilatations of intercellular spaces. At the level of these crypts, continuous junctions are formed somewhat later than are microvilli. This midgut differentiation coincides with deposition of the third embryonic (first larval) cuticle, and with a high titer of ecdysteroids. 相似文献
89.
Charles N. Rotimi Richard S. Cooper Susan L. Ataman Babatunde Osotimehin Solomon Kadiri Walinjom Muna Samuel Kingue Henry Fraser Daniel McGee 《Obesity (Silver Spring, Md.)》1995,3(Z2):95s-105s
A survey of the prevalence of hypertension and associated risk factors including obesity was carried out among persons of West African heritage currently living in societies at different stages of social, economic and technological development. We present here the distribution of several anthropometric variables and the prevalence of obesity in these populations. Using a standard protocol with centralized training of field staff, 7 439 men and women aged 24 to 75 from six multinational sites were recruited and examined. Although men were taller, women were more obese across sites. Body mass index (BMI) and consequently the prevalence of overweight and obesity increased with westernization from rural African subsistence farming communities to suburban Chicago. Average BMI increased with age until about age 54, and then began to decline or at least level off. The mean BMI for African-American men and women was 27.1 kg/m2 and 30.8 kg/m2, respectively. Men displayed high levels of centripetal fatness, measured as the waist-to-hip ratio (WHR), compared to the women across site. Based on the US Department of Agriculture guidelines, 22.6% and 56.9% of the African-American men and women had elevated WHR. Although account must be taken of the important contribution of an individual's genetic background, this multinational study of persons with similar heritage clearly shows the potent impact of current environmental factors on the distribution and level of obesity. 相似文献
90.
Nadia Aboulaich Hassan Bouziane Mohamed Kadiri María del Mar Trigo Hassane Riadi Mohamed Kazzaz Abderrahman Merzouki 《Aerobiologia》2009,25(1):27-38
Total pollen production per inflorescence and per square meter were studied in anemophilous species of the Poaceae family,
to determine the relative contribution of each species to the total load of pollen released and to identify the species with
the highest potential pollen emission. This was done by calculating the number of pollen grains per flower and per inflorescence
and by estimating the density of inflorescences in an area of one square meter. Pollen production per inflorescence varied
between 12,000 and 15 million grains, often being higher in the perennial species. Mountainous, grassland, riverside, and
littoral areas contributed similarly to the amount of pollen grain production per square meter. Species such as Gaudinia fragilis, Hordeum murinum, Lolium rigidum, and Trisetaria panicea, with high pollen records, were found in all the studied areas. Aerobiological analysis will be undertaken to determine the
main pollen season of Poaceae species. The results obtained are of great importance for respiratory health management in this
region. 相似文献