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81.
The immature stages of Protocalliphora maruyamensis Kano et Shinonaga are newly described and the third instar larva of P. azurea (Fallén) is redescribed from specimens collected in Japan. The larval morphology of Protocalliphora is discussed. A key to the third instar larvae of Japanese bird-parasitic blowflies is given.  相似文献   
82.
Intraspecific morphological variations of a Pleistocene solitary scleractinian coral, Cylindrophyllia orientatis (Yabe & Eguchi), have been examined based on 792 specimens. The specimens are discoidal to short cylindrical in shape, with no significant change in their diameter during skeletal growth. Septal arrangements of the coralla are observed on upper and basal surfaces. Septal numbers do not change through the ontogeny of each corallum, even when the last cycle of septa is incomplete. Septal arrangements and numbers are controlled by intrinsic genetic factors. Heights of the coralla are controlled by environmental factors where they lived If growth rates are presumed to be constant, heights can be regarded as indicating age of specimens. Assuming that this is the case, the survivorship curve shows that this fossil population had a constant death rate. Two varieties exist in this population: one has 20–28 septa, the other 30–48 septa, showing a dimorphic feature. Scleractinian coral, intraspecific variation, population, septa, species problem ,  相似文献   
83.
Genetic studies and quantitative determination of levels of 3-hydroxykynurenine and kynurenine were performed in an albino strain of a terrestrial isopod Armadillidium vulgare. From the results of matings between the albino and the albino, the red, the dark red, or the wild type individuals, the albino A. vulgare seems to be regulated by an autosomal gene(s) recessive to its wild allele. Litter mating of F1 progenies obtained by crossing the albino and the red mutant or the albino and the dark red mutant yielded progenies at a ratio of 3:6:3:4 for the red, the dark red, the wild, and the albino phenotypes, respectively. The albino gene(s) seems not to be allelic but to be epistatic to the red gene(s) with respect to ommochrome biosynthesis. Quantitative determination of 3-hydroxykynurenine carried out by high-performance liquid chromatography with electrochemical detection revealed that the 3-hydroxykynurenine content in the albino was significantly lower than that in the wild or the red type. The whole content of 3-hydroxykynurenine after enzymatic conversion of kynurenine to 3-hydroxykynurenine was still considerably lower than that found in the wild type, even though it increased after the conversion. The albino gene(s) seems to be associated with a blockage at distinct level(s) of ommochrome biosynthesis.  相似文献   
84.
The ontogenetic development of two Recent scleractinian corals, Golaxea fascicularis (Linnaeus) and Acrhelia horrescens (Dana), has been studied in serial thin sections. The origin of the septotheca (a collective term including both eutheca and pseudotheca) is reconsidered. The eutheca is found to be a basic skeletal structure of corals and of primary origin, formed directly from the basal plate, not by the thickening of septa. The eutheca prepares the way for the formation of metasepta. The ontogenetic growth of the metasepta is illustrated. The pseudotheca is formed by fusion of neighbouring septa and is entirely of secondary origin. Its development is occasional. The essential mural structure of oculinid corals with pseudothecal walls is euthecal.  相似文献   
85.
86.
The present study indicates that a factor in rabbit serum inhibits the in vitro steroid- and gonadotropin-induced maturation of oocytes of the teleost fish, Oryzias latipes. Such inhibitory activity could not be recognized in the serum of this fish or in the fluids from mammalian follicles. Passage of the serum inhibitor through a cellulose membrane indicated that it has a molecular weight of less than 3,500. The inhibitory activity on steroid-induced oocyte maturation was not destroyed by heating, by repeated freezing and thawing or by treatment with proteolytic enzymes, lipase or amylases. However, its activity could be removed by extraction with charcoal but not with ethyl ether or toluene. The inhibitory action of the heat-stable and dialyzable serum factor was reversible. The factor appears to exert its inhibitory effect upon the oocyte itself in an early step of maturation, rather than upon the follicle cells.  相似文献   
87.
The metabolism of sulfur of S-methyl-L-cysteine and ($)S-methyI-L-cysteinesulfoxide in Chinese cabbage was studied. Results showed thatthese sulfur-bearing amino acids are metabolized to cysteineby demethylation. This conclusion is based on; 1) the relativelyhigh recovery of radioactivity in the cysteine of the insolublefraction a short time after the administration of 35S-labeledS-methyl-L-cysteine or ($)S-methyl- L-cysteine sulfoxide; 2)the similarity in the ratios of 3H to 35S in the cysteine ofthe insoluble fraction and in the double-labeled cysteine partof S-methyl-L-cysteine and its sulfoxide fed to detached leavesand 3) the obvious structural relationship between cysteineand its methyl derivative, S-methyl-L-cysteine. Moreover, we ascertained that the sulfur of S-methyl-L-cysteinewas also utilized when supplied to plants; i.e. tomato, tobaccoand cucumber, in which this sulfur amino acid has not been found. (Received June 30, 1971; )  相似文献   
88.
RECENT progress in the definition of the DL-A antigens within a closely bred colony of beagles maintained at the Mary Imogene Basset Hospital (Cooperstown colony) has shown that these antigens are components of the principal system of histocompatibility (DL-A) in the dog1–3. Dausset and associates4 have described the segregation of DL-A antigens in 679 offspring of 151 consecutive matings within the Coopers-town colony. Through methods of backcross analysis, 23 DL-A haplotypes (that is, specificities determined by the DL-A region of one single chromosome) have been identified and the DL-A genotypes of 1,302 offspring of 517 matings in this colony have been defined4. This combined genetic and serological information has provided an opportunity to reassess the reported survival rates of allogeneic bone marrow transplantation in serologically matched littermate dogs5. We describe here the long term survival of bone marrow transplants and renal allografts obtained from the same donors in nine littermate and three non-littermate recipients selected on the basis of genetic and serological criteria of DL-A compatibility in the Cooperstown colony. The results are contrasted with the survival of twenty-two renal allografts performed in untreated recipients selected on the basis of similar criteria.  相似文献   
89.
Molecular investigation of the process of cold acclimation in woody plants has been limited by the superimposition of dormancy-related events on the process of cold tolerance development. To address this limitation, we have used the grape Vitis labruscana L. ev. Concord to develop a system in which the developmental programme of dormancy can be induced seperately from cold acclimation. Using this system we have characterized differential accumulation of several proteins in grape buds during the normally superimposed endodormancy and cold acclimation programmes, and in buds which have entered only the endodormancy programme. A set of 47 kD proteins accumulated during endodormancy without cold acclimation to a level similar to that found in endodormant and cold-acclimated buds, but without any associated increase in bud cold-acclimation level. However, a 27 kD LEA-like protein accumulated only in cold acclimated buds. We conclude that expression of the 47 kD glycoprotein is endodormancy-related, but is not strictly related to the development of cold acclimation, while the 27 kD protein appears to be more specific to cold acclimation. In addition to strengthening the association of LEA-like proteins with cold acclimation, this system allows more specific assessment of cold acclimation-associated phenomena in overwintering buds.  相似文献   
90.
The degree and type of melanogenesis, i.e., either eumelanin of pheomelanin, has been shown to be a reliable marker for the differentiation of the melanocyte. If exposed to UV light, these two melanins were reported to behave differently; eumelanin was photoprotective whereas pheomelanin was phototoxic to cultured tumor cells. Our previous study indicated that dysplastic melanocytic nevus (DMN) undergoes altered melanogenesis, forming pheomelanosome-like granules. The present study examined chemically the type and degree of melanin synthesized in 31 melanocytic nevi excised from 27 patients as compared with that occurring in the surrounding normal skin. The tissue content of eumelanin and pheomelanin was expressed by the amounts of pyrrole-2,3,5-tricarboxylic acid (PTCA) and aminohydroxyphenylalanine (AHP), respectively. We found that DMN lesions contain significantly higher amounts of pheomelanin than either common melanocytic nevus (CMN) or normal skin. Differences in pheomelanin content between DMN and CMN could not be accounted for by inherently higher levels of pheomelanin within the skin in general from DMN patients. Our present finding substantiates our previous claim that epidermal melanocytes in DMN undergo deranged melanogenesis.  相似文献   
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