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111.
The microsporida Nosema gastroideae and N. equestris, which are highly pathogenic for Leptinotarsa, have been successfully produced in some other chrysomelid species, Gastrophysa polygoni and G. viridula. As the principal target host, Leptinotarsa is very susceptible to these pathogens, and death occurs before massive sporulation by the microsporidia. By contrast, the infected larvae of G. polygoni or G. viridula are able to develop until the adult stage when most of the tissues become filled with spores. In addition, the larvae and adults of these species can be reared in the laboratory on Polygonum aviculare and Rumex obtusifolius. These plants have longer vegetative periods and are better sources of food than potato leaves. In both species of Gastrophysa the yields of spores related to unit weight were about five times higher than in Leptinotarsa. In the adults of G. viridula there was up to 4.8 × 106 spores mg?1 body weight of N. gastroideae, or 9.1 × 106 spores mg?1 of N. equestris. The higher content of microsporidian spores facilitates their purification and isolation.  相似文献   
112.
The pneumoconiosis developing after inhalation of air-borne dusts in the work place depends on the relation between the value of particle deposition in the respiratory tract and the rate of particle clearance from sites of their deposition. For testing the deposition in humans an aerosol of paraffin oil was given to a cohort of healthy persons. The characteristic parameters of the aerosol had been defined. The concentration of particles in 5 channels were measured in both the inhaled and exhaled air samples using the particle counter ROYCO 225. The deposition fraction was calculated from the relation of particle amount in expired air to the amount in inhaled air in each distribution class. In this preliminary report the results comparable with the prediction mathematical curve are discussed.  相似文献   
113.
114.
Nine species ofByssoloma Trevisan (Pilocarpaceae) are reported from a collection of foliicolous lichens from Zaire, and includeB. murinum sp. n. In addition,B. usambarense sp. n. is described from adjacent Tanzania. A determination key is provided to all the known African species, and each species is briefly characterized.  相似文献   
115.
The proteolipid subunit of H+-ATPase was labeled by [14C]N,N-dicyclohexylcarbodiimide in bovine heart mitochondria. The radioactive labeling was followed using various systems of sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). When using discontinuous SDS-PAGE (Laemmli, U.K., 1970,Nature (London)227, 680–685) a monomeric (Mr 7600±1500) and a dimeric form (Mr 17,800±1200) of the proteolipid were detected, while only the monomeric form was found on urea (8 M) containing gels (SDS-PAGE according to Laemmli; or Swank, R. T., and Munkers, K. D., 1971,Anal. Biochem. 39, 462–477). When using SDS-PAGE with Na-Pi buffer (Weber, K., and Osborn, M., 1969,J. Biol. Chem. 244, 4406–4442), only a dimeric form of the proteolipid (Mr 15,000±1000) was detected. Experimental data indicate that the different patterns of proteolipid separation are related to the presence of the two distinct proteolipid conformations in the SDS solution.  相似文献   
116.
Myosin content and phosphorus (P) concentration of myosin preparations were measured in non-pregnant and pregnant human myometrial tissue specimens. It was found that the amount of myosin gained from 1 g of minced myometrial tissue is 0.5 mg in the early follicular phase of the menstrual cycle, 0.6-0.7 mg in the late luteal phase, and 6-7 mg during pregnancy. Considering the different functional stages of the myosin sources and the performance characteristics of the methods, the estimated myosin content of non-pregnant myometrium is 1.0-1.5 mg, while 10-15 mg in pregnant myometrial tissue. A considerable amount of P is bound to the preparations. It is the smallest in the post-menstrual period and increases towards the end of the cycle. The largest amount of P is gained from fresh pregnant uterine samples. Analysis of the alkaline hydrolysate showed that the phosphate group was bound to amino acids, in the largest amount to arginine, less to histidine and the smallest amount to lysine and serine. As a function of the duration of storage, especially the P-Arg concentration was decreasing. The prolonged hydrolysis time decreases again the concentration of P-Arg with a consecutive increase of No. 1 and 2 P-containing peaks in the chromatographic profile of alkaline hydrolysate.  相似文献   
117.
Summary Lymphocyte-mediated lysis of autologous tumor cells (autologous lymphocyte cytotoxocity ALC) was tested at the time of surgery in 108 patients (46 squamous cell carcinomas of the lung, 25 adenocarcinomas of the lung, 19 soft tissue sarcomas and 18 osteosarcomas). The clinical course of these patients in relation to the test results has been published previously. The group was evaluated again after an extended observation time, now with a mean of 80.2 months (range 36–108). The test was rarely positive in patients with metastasis (2 out of 28 experiments).There was a correlation between the ALC results and the postsurgical clinical course for patients without detectable metastasis in that (1) a negative test was invariably a bad prognostic sign, i.e., all 32 patients with negative ALC died within 3 years (mean survival time 16.1 months). (2) The remission and survival times were longer for the ALC positive patients (p<0.001). (3) All 37 individuals who are alive at present without recurrence belong to the reactive group.The ALC results correlated with the clinical course in 88% of patients. The correlation was highest for the groups of soft tissue sarcoma and adenocarcinoma of the lung. There was no correlation between killing of K562 cells and ALC, or between lymphoproliferative response to PHA and ALC reactivity.  相似文献   
118.
The relationship between the activity of ATC oxygenase, CTC production and growth rate was investigated in a low-producing strain ofStreptomyces aureofaciens, closely related to the wildtype strain, and in a higher-producing variant. Different growth rates were achieved by using glucose, fructose and sucrose as carbon sources. Activity of the enzyme and CTC yield in both strains were inversely proportional to the rate of sugar utilization but in the higherproducing variant sugar utilization was slower than in the low-producing strain. The expression of ATC oxygenase was less sensitive to “catabolite repression” in the higherproduc ing strain. BT, a stimulator of CTC production, markedly inhibited growth of the higher-producing variant in a medium with slowly utilized sugars (fructose and sucrose) but had little effect on growth of the lowproducing strain. It also increased the level of ATC oxygenase in both strains under all experimental conditions. It could be established that there was no obligatory relationship between the increase of antibiotic synthesis and the increase of enzyme activity.  相似文献   
119.
Agrobacterium radiobacter, strain B6 (a strain isolated in this laboratory, which limited the occurrence of damping-off of sugar beet and influenced growth of plants in hot-house and field experiments) was found to produce an acidic exopolysaccharide in a mineral medium with various carbon sources. Hydrolyzates of the polysaccharide contained glucose, galactose, glycerol, succinic acid and pyruvic acid, whose quantitative content varied according to the carbon source used. The polysaccharide isolated from the medium containing glucose exhibited the highest physiological activity. Seeds germinated best and sugar beet roots were found to grow most rapidly in a medium containing 0.2 % (W/W) of the polysaccharide. The roots exposed for 3 d in this medium grew 2.7-fold as compared with non-treated plants. Higher sumbers of microorganisms were detected on the surface of roots treated with the polysaccharide. Growth of roots was also stimulated when immersing the seeds (30 min) in a 0.2 –0.4 % solution of this polysaccharide. After a two-fold treatment the roots were less damaged by the fungusPythium ultimum. Plants from seeds treated with the polysaccharide grew in the field soil more rapidly than the non-treated plants but worse than after bacterization of the seeds byA. radiobacter B6 and were only partially protected against the damping-off of sugar beet.  相似文献   
120.
Oudin’s principle of single immunodiffusion in agar gel was modified for quantitative determination of IgA in bronchoalveolar lavage (BAL) of normal 20–25 g mice. The reaction took place at 25 °C in 0.3 % agarose with 16.7 % pig serum against mouse IgA, and was evaluated on the basis of a relationship between the progress of the precipitin zone and the square root of time. The linear dependence of the derived constantk on the logarithmic concentration of antibody in the sample permitted to express the results as titre, corresponding to a dilution wherek = 0. Examination of seven samples of pooled blood serum of normal mice shoved taht (1) the IgA level was practically constant, (2) serum IgA possessed under given conditions similar properties as IgA from the bronchoalveolar secretion; it is therefore possible to employ pooled sera as a reliable control of the immunodiffusion system in ease of lack of reference standards with defined IgA content. Examination of 82 individual BAL samples of normal mice revealed that the mean IgA concentration in 2.5 mL samples was almost 1000 times lower than in blood serum.  相似文献   
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