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81.
The hot-spring waters of numerous hot springs at the Kamchatka Peninsula, Russia differ in their chemical characteristics and elemental composition. Total bacterial abundance (TBA) as well as enzymatically active and respiring bacteria was enumerated in water samples collected from the Nalychevskie, Oksinskie, Apapelskie, and Dachnye hot springs. 5-Carboxyfluorescein diacetate activity was detected in all water samples and comprised 29-65% of the TBA as determined by 4',6-diamidino-2-phenylindol staining. The respiratory activity of iron-oxidizing bacteria was assayed by 5-cyano-2,3-ditolyltetrazolium chloride reduction. Respiring cells accounted for 9-14% of the TBA, indicating a positive correlation with the number of iron-oxidizing bacteria from the hot-spring biomats. Enumeration of heterotrophic bacteria revealed a high-density bacterial population only in the water of the Apapelskie hot spring, which has a temperature of 36 degrees C. Therefore, it appears that heterotrophic and iron-oxidizing bacteria inhabiting the hot-spring waters are essential for the geochemical processes occurring in hydrothermal systems.  相似文献   
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An investigation of the microbial community of Lake Baikal by the methods of general and molecular microbiology showed that culturable bacterial strains are represented by various known genera. The lake water contains a great number of bacterial morphotypes, as revealed by electron microscopy, and a great diversity of nonculturable microorganisms belonging to different phylogenetic groups, as revealed by 16S rRNA gene fragment sequencing. The inference is made that the microbial community of Lake Baikal contains not only known species but also new bacterial species that are possibly endemic to the lake.  相似文献   
85.
A few alternatives of the binding of healthy patients plasma low density lipoproteins (LDL) with anion exchanger PBE-94 were revealed. In the first case the main part of LDL did not bind to the gel and the isoelectric points of the minor subfractions were 5.8 and 5.3, and pI 4.1. In the second case about half of lipoproteins did not bind to the gel, and the isoelectric points of subfractions were 5.7 and 5.0; and pI 4.1. In the third case when all lipoproteins bound to the PBE-94, there were much more subfractions and their isoelectric points were 6.2, 5.8, 5.2, 4.9, 4.5 and pI 4.1. All LDL of the patients with ischemic heart disease bound to anion exchanger, and the part of subfraction with pI 4.1 was three or five times as great as the one of the healthy person. Increasing of the LDL subfraction with pI 4.1 was observed at prolonged keeping of the LDL obtained from the healthy person plasma. LDL isoelectric point distribution of the persons with carcinoma uterine cervix did not differ from the one of the healthy persons. Acetylation and hexanol modification resulted in the isoelectric point shift from 5.7 to 4.6 and to 4.3 in the case of LDL subfraction to be obtained preparatively using the chromatofocusing.  相似文献   
86.
The study has shown that the ratio of elements in the secondary structure of LDL protein from patients with the coronary heart disease from health subjects is similar. However LDL protein is displaced by 0.5 nm towards the water phase in patients with CHD comparing with healthy subjects. It is likely that such differences are a result of the lower stability of LDL protein in CHD. It is supposed that the damage of lipoprotein particles (premodification) in CHD becomes atherogenic in the vessel wall after the action of additional factors.  相似文献   
87.
The phylogeny of selected genera from four subfamilies of fungus gnats (Diptera: Mycetophilidae) – Manotinae, Leiinae, Sciophilinae and Gnoristinae (including Metanepsiini) – is reconstructed based on the combined analysis of five mitochondrial (12S, 16S, COI, COII, cytB) and two nuclear (28S, ITS2) gene markers. Results of the different analyses all support Manotinae as a monophyletic group, with Leiinae as the sister group. Allactoneura DeMeijere is nested in the monophyletic and strongly supported clade of Leiinae. The tribe Metanepsiini is revealed as paraphyletic and the genera Metanepsia Edwards and Chalastonepsia Søli do not appear to be closely related. The genera Docosia Winnertz, Ectrepesthoneura Enderlein, Novakia Strobl and Syntemna Winnertz were placed with a group of genera included traditionally in the Gnoristinae. The monophyly of Dziedzickia Johannsen and Phthinia Winnertz is not supported. The genera of Sciophilinae (excluding Paratinia Mik but including Eudicrana Loew) form a monophyletic group in the Bayesian model.  相似文献   
88.
Russian Journal of Bioorganic Chemistry - A series of diterpenes that contain the morpholine, pyrrolidine, benzyl, nitrophenyl, and 1,2,3-tetrazole heterocyclic fragments have been synthesized from...  相似文献   
89.
The relationships between climate (January and July temperatures, annual precipitation, and a relative moisture index) and the number of foci and intensity of the needle cast disease caused by fungi from the genus Lophodermium Chevall. in the Scots pine nurseries and provenance trials in Krasnoyarsk krai have been studied using multivariate statistics methods. It is found that peaks in the disease occurrence are related to the warm and humid weather conditions. Bioclimatic models of the needle cast ranges have been built using the climate variables; the spatial dynamics of the disease occurrence have been projected under various scenarios of climate warming over the 21st century. Model experiments have shown that the needle cast disease would shift northwards into the new regions in Krasnoyarsk krai, where the phytopathogen has not yet been registered in the nurseries. The largest forest areas exposed to needle cast disease are predicted to be at a high risk of outbreaks by 2020 under moderate climate warming. With a significant warming trend by 2080, potential risk areas will be reduced, because the pine expansion into the permafrost zone should be limited by slow thawing of its active layer.  相似文献   
90.
We adapted a recently developed nonrestrictional, nonligational genome walking method, Universal Fast Walking (UFW), for detection of length polymorphism in the proximal promoter region of genes. We demonstrate its efficacy at discovering naturally occurring transposition into heat‐shock genes of wild Drosophila and show that it surmounts limitations of simple polymerase chain reaction (PCR) approaches. We further present modifications to the standard UFW protocol and provide some guidelines to improve specificity. Although the resultant banding pattern of a standard UFW can be regarded as a DNA fingerprint, many amplicons result from false priming and not real polymorphisms. We describe ways to distinguish between UFW amplicons and false priming products in a high‐throughput assay.  相似文献   
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