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811.
The acid-extractable, water-soluble, sulphated heteropolysaccharide, sargassan, contains residues of D-glucuronic acid, D-mannose, D-galactose, D-xylose, and L-fucose, and a protein moiety. Partial, acid hydrolysis of sargassan and auto-hydrolysis of the free-acid polysaccharide have been studied. Several acidic and neutral oligosaccharides were subsequently isolated. Evidence is advanced for the presence of ester sulphate on some galactose and fucose residues. It is concluded that the carbohydrate moiety of sargassan involves a backbone chain of D-glucuronic acid and D-mannose residues, and side chains involving residues of D-galactose, D-xylose, and L-fucose with sulphate attached to some galactose and fucose residues. 相似文献
812.
M F Hussein N A Ahmed S M Rawi 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1986,84(1):165-170
Levels of the amino acids GABA and glutamine were determined in the whole brain of the white albino rat Rattus norvegicus after daily injection of 1/2, 1/4, 1/8, 1/16, 1/32 and 1/100 LD50 of cyolane. With 1/2 LD50 an increase in the level of both GABA and glutamine in the brain was recorded. Dose levels of 1/4 and 1/8 LD50 caused an increase in the level of GABA and a decrease in glutamine concentration followed by an increase from the 7th and 11th days for 1/4 and 1/8 LD50, respectively. The induced increase in GABA level started from the 2nd week for 1/16 and 1/32 LD50 and from the 3rd week for 1/100 LD50. Dose levels of 1/16, 1/32 and 1/100 LD50 caused a fluctuating increase in glutamine concentration starting from the 2nd, 3rd and 6th weeks, respectively, which was followed by a fluctuating decrease at the 9th week for 1/32 and 1/100 LD50. These findings support previous findings that the enhanced transformation of glutamic acid to GABA and glutamine is a result of a disturbance in the metabolism of the glutamic acid-GABA and the glutamic acid-glutamine systems in the rat brain. 相似文献
813.
M. Hussein Khan 《Human genetics》1972,16(4):323-327
Summary A 67 year old male revealed in the preleukaemic stage of acute myeloid leukaemia a large population of bone marrow cells with trisomy C (47,XX,C+) and a side line with 2 extra C chromosomes (48,XY,2C+). It is suggested that the presence of side lines is a reliable cytogenetic criterion for the interpolation of chemotherapy in the preleukaemic phase. The leukaemic stage was irresponsive to chemotherapy.
Supported by the Deutsche Forschungsgemeinschaft, Bad Godesberg. 相似文献
Zusammenfassung Bei einem 67 Jahre alten Mann mit akuter Myeloblastenleukämie fand sich im Knochenmark ein dominanter Stamm mit Trisomy C (47,XY,C+) und eine Sublinie mit zusätzlichen C-Chromosomen (48,XY,2C+). Es wird angenommen, daß der Nachweis von Sublinien in der präleukämischen Phase ein zuverlässiges cytogenetisches Kriterium für die Anwendung eines Chemotherapeuticums ist. Die Leukämische Phase hat nicht auf eine Chemotherapie angesprochen.
Supported by the Deutsche Forschungsgemeinschaft, Bad Godesberg. 相似文献
814.
Muhammad Akhlaq Tarek R. Sheltami Hussein T. Mouftah 《Reviews in Environmental Science and Biotechnology》2012,11(3):305-322
Sand and dust storms (SDSs) are common phenomena in many parts of the world, which offer serious hazards to the environment, economy and health. An early warning of the approaching SDS would allow people to take precautionary measures and help minimize its terrible effects on the daily life. This requires continuous monitoring of the fugitive dust, sandstorms and movements of sandbanks in a certain area. Several technologies for monitoring of the dust and other environmental changes are available, such as lookout-tower, video-surveillance, sensory information, satellite imagery, unmanned aerial vehicle and hybrid approaches. A particular technology is suitable only for detecting the certain types of SDS, but a hybrid approach can detect many types of SDS. In this paper, we provide a quick review of the techniques and technologies for SDS monitoring. We provide an overview of the data requirements, dust modeling and techniques for SDS detection and prediction. We also summarize, classify and compare different technologies for SDS detection and prediction, and propose that a hybrid approach consisting of satellite imagery and wireless sensor networks is best suitable for detecting and predicting SDSs of all types. 相似文献
815.
Hashem Mahmoud Mohamed Ranya Fysal El-Homosy Abd-Ellatef Hesham Abd-Ellatef Fathi Mohamed Salh Mohamed Younes Hussein 《Geomicrobiology journal》2017,34(3):261-266
Thirty-five yeast strains were isolated from soil samples that were collected from different locations in Upper Egypt. The purified isolates were screened for the release potassium from mica on Aleksandrov agar medium. Two yeast isolates (KSY-29 and KSY-33) showed an ability to solubilize potassium by inducing clear zones around their colonies. They were identified as Pichia anomala and Rhodotorula glutinis, respectively, based on PCR analysis of the ITSI-26S region that was amplified by NL1/NL4 species-specific primers. The amount of K released from muscovite mica in the broth culture of the yeast isolates was measured after 5, 10, 15 and 20 days of the incubation at 25°C. Both yeast isolates were very effective in releasing K of muscovite in broth culture, recording 8.11–13.21 μg/ml that were released from muscovite mica after 20 days of incubation. The inoculation of maize (Zea maize) plants with these yeast isolates under different K levels (25, 50 and 100% of recommended dose of potassium, RDK) as potassium sulfate was tested on growth and K uptake by these plants in the greenhouse. Significant increases (p < 0.05) in plant height, root and shoot dry weights as well as K uptakes by shoots and roots maize plants occurred through the inoculation with KSY-29 or KSY-33 isolates. 相似文献
816.
817.
Abstract. Anopheles gambiae midgut extracts and haemolymph possessed agglutinins, titre 1:16 to 1:256, against human red blood cells (RBCs). Subjection of both tissues to protein precipitation reagents, organic chemical and selected protease, neuraminidase and other glycosidic hydrolase treatments revealed the haemagglutinins to be protein, most likely glycoprotein, in nature - not lipoprotein, lipid, glycolipid or nucleic acid. An.gambiae agglutinins were thermo-labile >40o C, affected by freezing and thawing treatments, and contained disulphide and hydrogen bonds on the basis of sensitivity following exposure to dithio-threitol and urea respectively. Optimum haemagglutination depended generally on slightly acid to neutral pH conditions and agglutinin activity was Ca2+ ion, albeit to a lesser extent Mg2+ ion, dependent. The midgut extract agglutinin subunit molecule had a relative molecular weight (Mr ) of 65kDa whilst that of haemolymph was 40kDa.
This study presents the first report on selected physico-chemical properties, the glycoproteinaceous nature and tentative subunit Mr of mosquito midgut extract and haemolymph anti-RBC agglutinin(s). 相似文献
This study presents the first report on selected physico-chemical properties, the glycoproteinaceous nature and tentative subunit M
818.
819.
An experimental study of the breakdown of submerged leaves by hyphomycetes and invertebrates in Morocco 总被引:3,自引:0,他引:3
SUMMARY. 1. Mechanisms of the breakdown of submerged leaves under the warm and dry Moroccan climate, including the interaction between hyphomycetes and invertebrates, were investigated.
2. Laboratory experiments were performed on dried leaves of Salix sp. and Nerium oleander .
3. During the first month under the experimental conditions, Melanopsis praemorsa, Physa acula (Gastropoda) and Hydropsyche maroccana (Trichoptera), respectively, were responsible for a loss of weight of 38, 21 and 13% in willow leaves, and 40, 15 and 8% in oleander leaves.
4. The weight lost by willow leaves inoculated with the fungi Alatospora acuminata, Anguillospora longissima, Lemonniera aquatica and Tetracladium marchalianum increased with time, but varied according to the fungal species. Loss of weight and increase in nitrate and phosphate content of the leaves were greatest with Lemonniera and smallest with Tetracladium .
5. When the leaves thus colonized by each of the four fungal species were exposed to each of the three invertebrates, the amount of material consumed increased with the time of fungal conditioning and varied according to the fungus and to the invertebrate. Greatest consumption was by Melanopsis feeding on leaves conditioned by Lemonniera , in which case assimilation percentage by the gastropod was as high as 75%.
6. Owing to their numbers in the field, and to the quantity of leaf material they ingest, gastropods appear as the main shredders in the streams considered, thus replacing the Crustacea that often play this part under temperate climates. Breakdown seems faster in Morocco than in France, mainly because of a shorter initial time lag in weight loss. 相似文献
2. Laboratory experiments were performed on dried leaves of Salix sp. and Nerium oleander .
3. During the first month under the experimental conditions, Melanopsis praemorsa, Physa acula (Gastropoda) and Hydropsyche maroccana (Trichoptera), respectively, were responsible for a loss of weight of 38, 21 and 13% in willow leaves, and 40, 15 and 8% in oleander leaves.
4. The weight lost by willow leaves inoculated with the fungi Alatospora acuminata, Anguillospora longissima, Lemonniera aquatica and Tetracladium marchalianum increased with time, but varied according to the fungal species. Loss of weight and increase in nitrate and phosphate content of the leaves were greatest with Lemonniera and smallest with Tetracladium .
5. When the leaves thus colonized by each of the four fungal species were exposed to each of the three invertebrates, the amount of material consumed increased with the time of fungal conditioning and varied according to the fungus and to the invertebrate. Greatest consumption was by Melanopsis feeding on leaves conditioned by Lemonniera , in which case assimilation percentage by the gastropod was as high as 75%.
6. Owing to their numbers in the field, and to the quantity of leaf material they ingest, gastropods appear as the main shredders in the streams considered, thus replacing the Crustacea that often play this part under temperate climates. Breakdown seems faster in Morocco than in France, mainly because of a shorter initial time lag in weight loss. 相似文献
820.
A saprolegniasis occurred in cultured sockeye salmon,Onchorhynchus nerka, raised in Hokkaido, Japan. The lesions were mainly observed in the head, peduncle region and the caudal fin. All strains
isolated were morphologically classified in the genusSaprolegnia. They were identified as a new species in the genus from the characteristics of the sexual organs, and namedSaprolegnia salmonis. 相似文献