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1.
Elio R.D. Castillo Dardo A. Martí Maximiliano M. Maronna María C. Scattolini Diogo C. Cabral‐de‐Mello María M. Cigliano 《Systematic Entomology》2019,44(1):61-74
In an attempt to unveil the origin of neo‐sex chromosomes in Ronderosia Cigliano grasshoppers, we performed a combined phylogenetic analysis based on morphological (external morphology and male genitalia) and molecular data (COI, COII, 16S and ITS2) to explore the chromosome evolution within the genus. We also analysed the distributional patterns of the various Ronderosia species and considered the possible role of chromosome rearrangements (CRs) in speciation processes within the genus in the light of ‘suppressed‐recombination’ models. We mapped the states of three chromosomal characters on the combined tree topology. The combined evidence supported Ronderosia as a monophyletic group. The cytogenetic analyses of the genus demonstrated the importance of rearranged karyotypes with single, complex and multiples neo‐sex chromosome determination systems in all species. The chromosome character optimisation suggests X‐autosome centric fusion as the mechanism responsible for neo‐sex chromosome formation in most Ronderosia species, except in R. dubia and R. bergii. Similar autosomes were involved in fusions with the ancestral X chromosome in Ronderosia, supporting previous hypotheses on the unique origin of X‐autosome fusion for the sex chromosome in the genus. As a source of chromosome variation, autosome‐autosome centric fusion played a secondary role in Ronderosia compared with other Dichroplini. Given the homogeneity in the morphological features, the sympatric distribution of closely related species and the intrinsic property of centric fusion as suppressors of the crossing over, we suggest that CRs may have played a key role during the speciation process within Ronderosia. 相似文献
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3.
A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan. 相似文献
4.
Margot S. Kruskall MD Elizabeth E. Eynon Zuheir Awdeh Chester A. Alper Edmond J. Yunis 《Immunogenetics》1987,26(4-5):216-219
The HLA class I antigen B44 is found in each of two different extended major histocompatibility haplotypes (allele combinations of HLA-B, HLA-DR, and complement genes BF, C2, C4A, and C4B in linkage disequilibrium). Using isoelectric focusing, two variants of HLA-B44 were identified. The basic variant was found in all cell lines with the extended haplotype HLA-B44, DR7, FC31, and the acidic variant in all cell lines with the extended haplotype HLA-B44, DR4, SC30. The occurrence of each antigen variant with a unique extended haplotype explains previous observations concerning the nonrandom association of B44 variants with DR antigens. 相似文献
5.
Transbilayer movement of bile acids in model membranes 总被引:6,自引:0,他引:6
The ability of bile acids to traverse membranes has important implications for their reabsorption from the gut, recirculation to and uptake into the liver, and resecretion into bile. The rate constant for transbilayer movement, or "flip-flop", of three common, unconjugated bile acids was determined by 13C nuclear magnetic resonance spectroscopy. At high pH, the sodium salts of the bile acids did not appreciably traverse the bilayer; however, upon protonation a rapid equilibration between the inner and outer monolayers occurred. The rate of flip-flop of each bile acid at 37 degrees C was found to be dependent on both number and location of hydroxyl groups but not on concentration in the bilayer over the range studied (2-4 wt%) nor on the presence of a different bile acid in the same bilayer. 相似文献
6.
An extractive fermentation system using immobilized yeast cells was developed to study the ethanol production at high sugar concentrations. Organic acids were used as extracting solvents of ethanol and their toxicity was tested in free and k-carrageenan entrapped cell preparations. Immobilization seems to protect cells against solvent toxicity, when long-chain organic acids, e.g., oleic acid, were used, probably due to steric and diffusional limitations, the free cells not being viable at high oleic acid concentrations. The entrapped cells also present a higher metabolic activity than their free counterparts at high glucose concentrations. A solution of 300 g/L of glucose was totally fermented by the immobilized yeast cells, which when free cannot normally convert more than 200 g/L. In situ recovery of ethanol by oleic acid in a batch immobilized cell system led to higher ethanol productivities and to the fermentation of 400 g/L, when an oleic acid/medium ratio of 5 was used. 相似文献
7.
Paracoccidioidomycosis was induced in immunized (IM) and non-immunized (NI) mice. The histopathology, the number of fungi in the lungs, the cellular (footpad test — FPT and macrophage inhibition factor assay — MIF) and humoral (immunodiffusion test) immune response were investigated serially postinfection. In the IM mice, at days 1 and 3, there was intense and predominant macrophagic-lymphocytic alveolitis with loose granulomatous reaction; at day 30, inflammation was mild. In the NI group, up to day 3, the lesions were focal; later there was formation of extensive epithelioid granuloma. The number of fungi in IM mice were always smaller than those of NI group. Immunization alone induced positive FPT and MIF indices with low titer of antibody. After infection, there was a significant decrease of the FPT indices in the IM group, which we interpreted as desensitization due to trapping of sensitized lymphocytes in the lungs. In conclusion, (1) The lesional pattern of pulmonary paracoccidioidomycosis in IM mice was similar to that of a hypersensitivity pneumonitis. This reaction was probably effective in reducing the extension of the infection and decrease the number of fungi. (2) In this model, pulmonary resistance against P. brasiliensis seems to be related to local and systemic delayed-type hypersensitivity reaction. 相似文献
8.
Yoshinori Nio MD Takahiro Shiraishi Michihiko Tsubono Hideki Morimoto Chen-Chiu Tseng Kazuya Kawabata Yoshikazu Masai Manabu Fukumoto Takayoshi Tobe 《Biotherapy》1992,4(2):81-86
The present study was designed to evaluate the effects of a recombinant human G-CSF (rhG-CSF) and a mutein G-CSF(KW-2228) on leucopenia and tumor growth in mice treated with 5-fluorouracil (5-FU). In normal mice, the number of leucocytes (white blood cell, WBC) reached the peak 12 hours after a single injection of either type of G-CSF and decreased to the normal level after 24 hours. Daily administration induced a continuous increase in the WBC count, however, administrations at intervals did not. Meth-A fibrosarcoma was subcutaneously inoculated into the backs of syngeneic BALB/c mice. The mice were treated with 5-FU alone or with G-CSFs. Chemotherapy with 5-FU alone resulted in leucopenia and an insignificant inhibition of tumor growth. The conjunctive administration of G-CSFs with 5-FU resulted in a significantly augmented inhibition of tumor growth, and leukopenia was not seen. This augmenting effect was more prominent with KW-2228.These results suggest that in 5-FU chemotherapy G-CSFs may be beneficial in restoring the number of leucocytes from leucopenic state and in augmenting the tumor inhibitory effect. Furthermore, KW-2228 may be more beneficial than the natural type rhG-CSF. 相似文献
9.
R. A. Santos J. C. G. Caldeira H. M. Pinheiro J. M. S. Cabral 《Biotechnology letters》1991,13(5):349-354
A novel aqueous two-phase system, based on polyethyleneglycol (PEG) and monosodium glutamate, was tested for the 1-dehydrogenation of hydrocortisone-based substrates. This system led to higher substrate solubilities and biocatalyst/steroid separation levels when compared with alternative systems. The addition of short-chain monohydric alcohols resulted in higher solubilities and more favourable partition coefficients for the tested substrates. Bioconversion activities in PEG/glutamate systems with 2,5% (v/v) methanol were comparable to those measured in monophasic buffer-methanol medium. 相似文献
10.
Giuseppe Familiari MD Vincenzo Toscano Pietro M. Motta 《Cell and tissue research》1985,240(3):519-528
Summary Morphological alterations induced by dehydroepiandrosterone (DHA) were studied in polycystic mouse ovaries (PCO). Treated mice showed ovulatory failure and cystic changes; cysts and follicles in various stages of growth and atresia were present although corpora lutea were absent. The levels of testosterone, dihydrotestosterone, 3- and 3-androstanediol, estrone and androstenedione increased, whereas estradiol was not detectable.The ultrastructure of granulosa cells in healthy and atretic follicles was similar to that of control animals, although the membrana granulosa in cysts was reduced to a monolayer of flattened cells. The theca interna of healthy and atretic follicles and ovarian cysts showed ultrastructural signs of abnormal steroidogenic stimulation.No significant differences (0.7<P<0.8) were found between the extensive surface area of gap junctions of healthy follicles of control and DHA-treated animals. On the P-face of granulosa cells of large healthy follicles, meandering strands of tight junctional particles were observed; their average length was significantly longer than those in healthy follicles of control animals (P<0.001). This increase was probably related to the large amounts of androgens present in the treated animals.Theca interna cells possessed small gap junctions; no significant differences (P>0.9) in gap-junction surface area were observed between DHA-treated and control animals. These results suggest that the size of gap junctions is probably unrelated to the steroidogenic activities of theca cells.The following trivial names have been used: Dihydrotestosterone: 5-androstan 17 ol-13 one; 3-androstanediol: 5-androstan 3,17 diol; 3-androstanediol: 5-androstan 3,17 diol 相似文献