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A test system permitting the detection of influenza virus protein M at a concentration of 0.1-0.5 ng/ml in ELISA has been developed. The use of this system made it possible to detect influenza viruses A and B directly in crude virus-containing material and clinical samples obtained from influenza patients. During the outbreak of influenza in the spring of 1983 ELISA was successfully used for the rapid diagnosis of influenza, and some of its advantages in comparison with the conventional immunofluorescence test were thus demonstrated. To overcome difficulties arising from the low immunogenic potency of protein M, in the process of obtaining diagnostic sera and ascitic fluids the animals were immunized with the conjugate of protein M and polyelectrolite, which ensured considerable activation of humoral immune response.  相似文献   
3.
O A Smirnova  N V Stepanova 《Biofizika》1975,20(6):1095-1098
A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases.  相似文献   
4.
The antigenic structure of the L-forms of salmonellae (S. typhimurium and S. typhi) in comparison with that of the initial bacterial cultures and revertant cultures was studied with the use of the immunoferritin method. The L-forms of salmonellae were found to retain an insignificant amount of O-antigen, as well as to have K-antigen on the surface of the cytoplasmic membrane, but in a lesser amount than the initial strains. In the cultures reverting from the L-forms of S. typhimurium and S. typhi the quantitative and qualitative characteristics of O- and K-antigens were completely restored.  相似文献   
5.
In this paper we demonstrate the study of plant water balanceby the non-invasive measurement of tissue water content andwater flow using proton nuclear magnetic resonance (NMR). Sapvelocity and flux were measured independently in the presenceof an excess of stationary tissue water. The instrumentationdescribed allows automated and unattended measurement of flow-and water content-variables in a well-defined region of theplant over periods of several days, with a time resolution betweensuccessive measurements of c. 5 s. Using this apparatus theeffect of changes in light intensity (day/night rhythm) andrelative humidity on stem tissue water content as well as onthe velocity and flux of xylem sap in the stem were investigatedin a cucumber plant. The results are in agreement with predictionsfrom a simple model for plant water balance, which is basedon water potential, flow rate and resistance to flow. As longas only transpiration is varied, flow rate and water content(or potential) are affected in opposite ways as demonstratedin this paper. In contrast, the model predicts that changesin uptake (resulting from changes in, for example, root resistance)will induce changes in water content and flow in the same direction.An experimental verification of this prediction is given ina subsequent paper, where, in addition, the NMR results arecompared to those obtained with a dendrometer. Key words: Water balance model, Cucumis sativus L., flow, water content, NMR, water balance measurement  相似文献   
6.
The content of cytochrome P450 and monooxygenase activity has been studied in the liver of Baikal fishes (Coregonus automnalis, Thymallus articus, Brachymystax lenok and Cottocomphorus greminsky). The administration of 3-methylcholanthrene increases considerably the level of metabolic activity of microsomal fraction and cytochrome P450 content in liver. The data of microsomal fractions of rats and fishes liver electrophoresis have shown that xenobiotic causes the synthesis of similar according to the molecular weight forms of cytochrome P450 in these animals. The induction of microsomal monooxygenase inhibits the lipid peroxidation of microsomal fraction.  相似文献   
7.
The survival rate of Mycobacterium lacticolum and the proportion between its R, S and M variants were studied in the course of 12 months under different conditions of storage (freeze-drying, under vaseline oil, in 0.85% NaCl solution and in distilled water). A high survival rate of the variants was found in cells freeze-dried in a protective medium containing 10% of sucrose +1% of gelatin as well as in a 0.85% solution of NaCl.The survival rate of te variants differed by 2--3 orders of magnitude in cells freeze-dried with sodium glutamate or suspended in distilled water. The proportion between the R, S and M variants in the population noticeable changed after storage under these conditions.  相似文献   
8.
Wine vinegar is a product obtained from wine acidification which contains at least 5% by wt. of acetic acid, in general without any additives or colorings.
Aspects studied in this work include: the determination of the taste group thresholds (geometric mean of the individual best-estimate thresholds "BET") of two different acids (citric and acetic acids) in aqueous solution and spanish vinegars produced from table and sherry wines. The results obtained suggest that wine vinegar can be considered something more than just an acidulant agent.
In order to evaluate differences among wine vinegars, discriminant tests for twenty-five spanish vinegars (sherry, table and flavored vinegars) were applied. Six of the twelve attributes freely chosen by assessors allowed grouping of the spanish wine vinegars according to their sensory aspects.  相似文献   
9.
When exponentially growing KB cells were deprived of arginine, cell multiplication ceased after 12 h but viability was maintained throughout the experimental period (42-48 h). Although tritiated thymidine ([(3)H]TdR) incorporation into acid-insoluble material declined to 5 percent of the initial rate, the fraction of cells engaged in DNA synthesis, determined by autoradiography, remained constant throughout the starvation period and approximately equal to the synthesizing fraction in exponentially growing controls (40 percent). Continous [(3)H]TdR-labeling indicated that 80 percent of the arginine-starved cells incorporated (3)H at some time during a 48-h deprivation period. Thus, some cells ceased DNA synthesis, whereas some initially nonsynthesizing cells initiated DNA synthesis during starvation. Flow microfluorometric profiles of distribution of cellular DNA contents at the end of the starvation period indicated that essentially no cells had a 4c or G2 complement. If arginine was restored after 30 h of starvation, cultures resumed active, largely asynchronous division after a 16-h lag. Autoradiographs of metaphase figures from cultures continuously labeled with [(3)H]TdR after restoration indicated that all cells in the culture underwent DNA synthesis before dividing. It was concluded that the majority of cells in arginine-starved cultures are arrested in neither a normal G1 nor G2. It is proposed that for an exponential culture, i.e. from most positions in the cell cycle, inhibition of cell growth after arginine with withdrawal centers on the ability of cells to complete replication of their DNA.  相似文献   
10.
Toxicity of bleomycetin was studied on 3 animal species (rats, rabbits and dogs). The antibiotic was administered intramuscularly and intravenously in various doses for a prolonged period of time. The death of the rats, rabbits and dogs treated with repeated lethal doses of bleomycetin was due to its toxic effect on the kidneys and probably lungs. The level of urea in the blood of the animals before death increased up to 300--400 mg %. Histological examination of the kidneys revealed the picture of glomerulonephritis. The lungs were highly plethoric and showed areas of alveolar collapse and consolidation consisting mainly of the collapsed alveolar epithelium. The liver was not affected by bleomycetin according to both the results of some functional tests and histological examination. tthe blood sugar level after bleomycetin administration was not altered significantly. The changes in the peripheral blood were not pronounced. An increased P wave, decreased R wave and deep S wave were seen on the ECG. Such deviitions may be due not only to the changes in the myocardium but also to the lung affection. When bleomycetiin was used repeatedly in nonlethal doses (1 mg/kg for rats, 1--2 mg/kg for rabbits and 0.25--0.5 mg/kg for dogs), the above changes were less pronounced or not manifested at all. No inhibitory effect on hemopoiesis is an important positive characteristics of bleomycetin, so that it compares very favourably with most other antitumor drugs.  相似文献   
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