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41.
蝉的变音调复合声和发声机制的分析   总被引:3,自引:1,他引:2  
蒋锦昌  徐慕玲 《昆虫学报》1991,34(2):159-165
蛙鸣蝉(Meimuna opalifera (Walk).ab.punctata Kato)的自然鸣声为“ji…guái”的重复单变调复合声.“ji”为主音频约4800Hz的准单音;“guái”的波形和主音频呈明显的演变,优势主频约2100Hz和2800Hz的变音调声.鸟鸣蝉(Meimuna opalifera (Walk)var.formosana Kato)的自然鸣声由重复的“jiū…ruǎ”和“jiū…gū…”合成的双变调复合声.“jiū”为基频和主频分别约625Hz和2100—2300Hz的准单音;“ruǎ”的波形和主音频呈明显的演变,基音和优势主频分别约575—625Hz和1550—1750Hz的变音调声.“gū”为优势主频约625Hz的准单音.变音调复合声不仅与腹部运动有关,而主要取决于发声肌的收缩特性和发声膜肋结构的振动特性.  相似文献   
42.
Summary The effects of four lysimeter soil series under three salinity levels were evaluated for grain yield, wt/1000 seeds, protein, and amino acids in Mexican dwarf wheat (Triticum aestivum L. var. Cajeme 71). The soil series consisted of: Holtville clay loam, Greenfield sandy loam, San Emigdio sandy loam, and Altamont clay loam. The irrigation water salinity levels were designated: low –2.2 mmho, medium –4.2 mmho, and high –7.1 mmho.No significant differences were found in the amount of grain harvested or wt/1000 seeds in the 1976 crop produced on the differential soil series. The yield of the 1977 crop was significantly affected by the soil types.Effects of soil type on the protein amino acids in the grain in both years were similar. Significantly higher protein amino acid levels of histidine, arginine, aspartic acid, threonine, serine, glutamic acid, glycine, alanine, cystine, valine, methionine, isoleucine, leucine, tyrosine, and phenylalanine were found in the grain grown on Altamont clay loam soil than the other types.The free amino acids in grain from the 1976 and 1977 crops were similarly affected by the soil types, except that the quantitative values of the free amino acids were substantially lower in 1977 than in 1976. The free amino acids significantly influenced by soil types were tryptophane, lysine, arginine, aspartic acid, threonine, serine, glycine, alanine, valine, isoleucine, tyrosine, and phenylalanine. In both years' crops, the sum of the free amino acid fractions was significantly higher in the grain produced on the Altamont soil than on the other soils.Salinity level in the irrigation water did not affect the 1976 crop yield or wt/1000 seeds. Although yields of the 1977 crop were significantly reduced by salinity, the wt/1000 seeds was not. The sum of protein amino acids was significantly higher in the 1976 and 1977 grain crops irrigated with high salinity water than in low salinity irrigated crops.An increased salinity irrigation water significantly reduced the sum of free amino acid fractions in the 1976 grain crop. Since some of the free amino acids in the 1977 grain crop increased while the others decreased due to the salinity level in the irrigation water, the sum of the free amino acid fractions was not significantly influenced.Significant interactions were found between soil types and salinity levels on free arginine, threonine, serine, glutamic acid, and alanine, and also on the sum of the free amino acids in the 1976 wheat grain. In the 1977 wheat grain, there were significant interactions between soil types and salinity levels on the free glutamic acid, valine, leucine, tyrosine, and phenylalanine, and on protein serine, glutamic acid, glycine, alanine, and the sum of the protein amino acids.The amounts of essential amino acids expressed as mg of amino acid/g of protein were not affected by the soil types or salinity levels. With the exception of lysine, and possibly threonine and methionine plus cystine, the essential amino acids were present in the grain at concentrations equal to or greater than recommended by WHO and FAO.  相似文献   
43.
Summary An attempt was made to study the number of species belonging to Cyanophyceae, Chlorophyceae and Bacillariophyceae in Lateritic, Red and Black soils and also Dry lands (jowar, cotton and wheat) and Wet lands (paddy and sugar cane). Lateritic and black soils had a poor algal flora and in general sandy soils were rich. Cyanophyceae appeared to be more resistant than Chlorophyceae and Bacillariophyceae to desiccation. Part of the Ph.D. Thesis approved by the Karnatak University (1976).  相似文献   
44.
The hypotheses that quantitative variation in leaf resins in the leguminous genus Hymenaea may partially be a response to insect predation was tested in feeding experiments with the generalist herbivore, the beet armyworm, Spodoptera exigua Hübn (Noctuidae). Leaf resins of all Hymenaea species are comprised of essentially the same suite of sesquiterpene hydrocarbons, but discrete quantitative patterns have been classified as Compositional Types based on the amounts of major components. In this work pure extracts of leaf resins of Type I (high - and β-selinene), Type II (intermediate amounts of -and β-selinene and caryophyllene) and Type III (high caryophyllene) were incorporated into an artificial diet for the insects at 1 and 3.2% (dry wt). Resin Type treatments produced differential dose-dependent effects on growth rate (lower larval weights and increased time to pupation) and in mortality. More significant inhibitory effects occurred in Compositional Types with a predominance of a single compared (i.e. Types I and III). Significantly higher mortality occurring in Type III treatments suggests that caryophllene may have higher potential toxicity than - and β-selinene for S. exigua. These experiments indicate that feeding by generalist herbivores could be a factor determining quantitative compositional variation: (a) among populations; (b) during the development of leaves; (c) in the spatial distribution within the leaves; and (d) between parent tree and seedling progeny.  相似文献   
45.
Summary Rats, 6 weeks old, were subjected to a program of endurance running for 3, 6 and 12 weeks. 0.5 to 0.8 m thick sections of Epon embedded soleus muscles were studied with morphometric methods.In cross-sections the area occupied by subsarcolemmal mitochondria was independent of the age, but was 53% higher after 12 weeks of training. The mean depth of the zones with subsarcolemmal mitochondria increased only 15% to about 0.9 m. Thus, the subsarcolemmal mitochondria showed a pronounced spreading at the muscle fiber surface in trained muscles. — The number of capillaries per fiber decreased slightly in controls and increased not significantly in trained muscles.It is concluded that the subsarcolemmal mitochondria supply the energy for the active transport of metabolites through the sarcolemma in oxidative muscle fibers, and that they are the limiting factor for endurance performance of the soleus muscle fibers because the changes in the capillarization were only small. It is suggested that the subsarcolemmal and the interfibrillar mitochondria have different functions and may therefore represent different types of mitochondria which can be distinguished by their morphology as well as by their biochemical properties.  相似文献   
46.
Summary Dry-mount autoradiography was combined with peroxidase immunocytochemistry to examine estrogen uptake in four pituitary cell types. Quantification by silver grain counts was used to compare 3H-estradiol uptake in nuclei of pituitary cells 60 min after i.v. injection into short-term (control) and long-term ovariectomized and in long-term thyroidectomized rats. Under all three hormonal states, the order of labeling intensity was: gonadotropes > somatotropes > lactotropes > thyrotropes. Long-term ovariectomy caused a significant increase in estrogen uptake of gonadotropes, somatotropes and lactotropes, while uptake in thyrotropes decreased. Long-term thyroidectomy decreased uptake in somatotropes, lactotropes and thyrotropes while gonadotropes remained unchanged.Supported by NICHHD grant HD-03007 to D.A.K., NICHHD grant HD-03110 to the Biological Sciences Research Center of Child Development Research Institute and a grant from the Rockefeller Foundation to the Laboratories for Reproductive Biology.  相似文献   
47.
Four types of acidophilic granular cells, in addition to B-cells, are identified in the islet organ of anadromous specimens of two subspecies of Petromyzon marinus by light and electron microscopy. Three of these acidophils (PI, PII and PIV-cells) occur in both the cranial and hepatic islets while a fourth type (PIII-cell) has only been found in the hepatic islet of some animals. The granules of the PI-cells stain with ponceau de xylidine, give a distinct tryptophan reaction and in ultrastructural examination show large, dense granules. The PII-cells contain unusual crystals and appear to be a non-secretory stage of the PI. The PIII-cells stain deep-red and acid fuchsin. They contain very large, dense granules and some lysosomes. PIV-cells stain selectively with phosphotungstic acid-hematoxylin and ultrastructurally, contain small, more or less dense granules. It appears that PI- and PIV-cells develop directly from B-cells, while the PIII-cells derive from PI-cells. despite their direct or indirect origin from B-cells, the PI-, PIII- and PIV-cells show characteristic features of functionally independent endocrine cells. Petromyzon marinus may be an ideal model for the understanding of phylogenetic and pathological interrelationships between islet and gastrointestinal hormones. It is clear that the interpretation of the islet organ of the cyclostomes, which has been generally considered a source of insulin only, requires a revaluation.  相似文献   
48.
Summary The endocrine pancreas of the bullhead catfish, Ictalurus nebulosus, and the channel catfish, I. punctatas was studied by light and electron microscopy. In addition to the usual A, B and D cells, a fourth endocrine cell type was consistently observed in the electron microscope. All endocrine cell types were innervated. The vesicles of most of the nerve endings were ultrastructurally different from typical adrenergic and cholinergic vesicles, strongly suggesting the possibility of a third autonomic neurotransmitter serving as a regulator of catfish islet secretion.Supported in part by PHS grant AM 11407 awarded to Dr. Bryce Munger.  相似文献   
49.
The responses of single vibratory receptors and ascending ventral cord interneurones were studied extracellularly in Gryllus campestris L. The physiology of the vibration receptors resembled those found in tettigoniids and locusts. The frequency responses of the subgenual receptors provide two possible cues for central frequency discrimination: differences in mean tuning between groups of receptors in the different leg pairs and a range of receptors tuned to different frequencies within one subgenual organ.Most of the ascending vibratory interneurones were highly sensitive in either the low or high frequency range. Broadbanded neurones were less sensitive. The characteristic sensitivity peaks of these units are due mainly to receptor inputs from a particular leg pair, although most central neurones receive inputs from all 6 legs. Only one neurone type, TN1 received excitatory inputs from both auditory and vibratory receptors; its responses were greatly enhanced by the simultaneous presentation of both stimulus modes. The responses to sound stimuli of AN2, on the other hand, were inhibited by vibration. No other auditory interneurones investigated were influenced by inputs from vibration receptors. Central processing of vibratory information in the cricket is compared with that of tettigoniids and locusts.  相似文献   
50.
The effect of an endurance training program lasting 17 weeks was studied in two cyprinid species, Chondrostoma nasus (L.) and Leuciscus cephalus (L.). Red, intermediate and white axial muscle were investigated. Morphometrical analysis revealed that training induced, in both species, increased red and intermediate muscle mass, fibre diameter and capillarization. Differences between species in the response to training were observed for volume densities of mitochondria and lipid. In contrast to C. nasus, L. cephalus show higher values for these compartments in red and intermediate fibres. The results are considered adaptational changes which increase the aerobic capacity of red and intermediate muscle fibres to meet higher sustained swimming activities.  相似文献   
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