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排序方式: 共有177条查询结果,搜索用时 31 毫秒
1.
Rats were given 7 days pre-treatment with either water (p.o.), 1 h immobilization or 20% ethanol (p.o.) with or without concomitant indomethacin injection. Following the pre-treatment phase, rats from each pre-treatment group were exposed to either 3 h cold-restraint stress or to 100% ethanol p.o. Results indicated that immobilization and 20% ethanol pre-treatment significantly reduced both cold-restraint stress ulcer formation and 100% ethanol-induced ulcers. Indomethacin co-treatment attenuated the reduction of ulcer formation of both pretreatments. These results suggest that "cross-stressor" adaptive cytoprotection occurs. Indomethacin abolished these effects, implicating the involvement of endogenous prostaglandins in the mediation of "cross-stressor"-induced gastric cytoprotection. 相似文献
2.
Summary The fine structure of the infundibular process of the hedgehog has been studied, using material fixed in osmium tetroxide and embedded in Vestopal W. The process resembles in general structure that of other mammals, but also shows features not previously described in other species.The nerve fibres contain a number of inclusions, namely: small vesicles, 300–500 Å in diameter; larger vesicles, up to 2000 Å in diameter, which contain a variable amount of osmiophilic material; hexagonal crystal-like bodies, approximately 1250 × 3000 Å in size, lying within a striated membranous sheath; and aggregate bodies made up of small electron dense granules, possibly derived from mitochondria.In addition complex multilamellate bodies occur in some nerve fibres, which apparently give rise to membranous vesicles. Pituicytes, of varying appearance, are often intimately related to the nerve fibres.The findings suggest that synthesis of material may occur in the distal part of the fibres of the hypothalamo-hypophysial tract.We are indebted to the Medical Research Council, who provided the electron microscope in the Department of Anatomy, University of Birmingham, which was used in this study. 相似文献
3.
Properties of fetal and adult red blood cell arginase: a possible prenatal diagnostic test for arginase deficiency. 总被引:4,自引:2,他引:2
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Prenatal diagnosis of inborn errors of metabolism has been possible only if the enzyme affected is expressed in amniotic fluid cells grown in culture. Arginase is essentially undetectable in normal human fibroblasts, amniotic fluid, and amniotic fluid cells but is present in high amounts in red blood cells. It is absent in the red blood cells of patients with liver arginase deficiency. The properties of the enzyme in the red cells of healthy children and adults were compared to those of the enzyme obtained from cord blood red cells of 13--20-week fetuses obtained at hysterotomy. The activities, heavy metal requirements, heat stability, pH optimum, kinetic properties, and reaction with anti-arginase antibody were examined. Both enzyme species were either identical or substantially similar by all criteria. The adult and fetal enzymes are, therefore, probably determined by the same structural gene. Fetal red cells obtained during amniocentesis and amnioscopy should then be a suitable tissue to use to make the prenatal diagnosis of arginase deficiency. 相似文献
4.
A correlation between BCL-2 modifying factor,p53 and livin gene expressions in cancer colon patients
Eman AE. Badr Mohamed FA. Assar Abdel Monem A. Eltorgoman Azza Zaghlol Labeeb Gehad A. Breaka Enas A. Elkhouly 《Biochemistry and Biophysics Reports》2020
Accumulating evidence has revealed that livin gene and BCL-2 modifying factor (BMF) gene are closely associated with the initiation and progression of colon carcinoma by activating or suppressing multiple malignant processes. Those genes that can detect colon - cancer are a promising approach for cancer screening and diagnosis. This study aimed to evaluate correlation between livin, BMF and p53 genes expression in colon cancer tissues of patients included in the study, and their relationship with clinicopathological features and survival outcome in those patients. In this study, 50 pathologically diagnosed early cancer colon patients included and their tissue biopsy with 50 matched adjacent normal tissue, and 50 adenoma tissue specimens were analyzed for livin gene and BMF gene expressions using real time PCR. The relationship of those genes expressions with clinicopathological features, tumor markers, Time to Progression and overall survival for those patients were correlated in cancer colon group. In this study, there was a significant a reciprocal relationship between over expression of livin gene and down regulation of BMF and p53 genes in colon cancer cells. Livin mRNA was significantly higher, while BMF and p53 mRNA were significantly lower in colorectal cancer tissue compared to benign and normal colon tissue specimens (P < 0.001), however, this finding was absent between colon adenomas and normal mucosa. There was a significant association between up regulation of livin and down regulation of BMF and p53 expressions with more aggressive tumor (advanced TNM stage), rapid progression with metastasis and decreased overall survival in cancer colon patients, hence these genes can serve as significant prognostic markers of poor outcome in colon cancer patients. This work highlights the role of livin, BMF and p53 genes in colorectal tumorigenesis and the applicability of using those genes as a diagnostic and prognostic markers in patients with colon carcinoma and as a good target for cancer colon treatment in the future. 相似文献
5.
JA Kiernan 《Biotechnic & histochemistry》2013,88(5-6):203-210
Hexazonium pararosaniline is a valuable reagent that has been used in enzyme activity histochemistry for 50 years. It is an aqueous solution containing the tris-diazonium ion derived from pararosaniline, an aminotriarylmethane dye, and it contains an excess of nitrous acid that was not consumed in the diazotization reaction. Other investigators have found that immersion for 2 min in an acidic (pH 3.5) 0.0015 M hexazonium pararosaniline solution can protect cryostat sections of unfixed animal tissues from the deleterious effects of aqueous reagents such as buffered solutions used in immunohistochemistry, while preserving specific affinities for antibodies. In the present investigation hexazonium pararosaniline protected lymphoid tissue and striated muscle against the damaging effects of water or saline. The same protection was conferred on unfixed sections treated with dilute nitrous or hydrochloric acid in concentrations similar to those in hexazonium pararosaniline solutions. Model tissues (solutions, gels or films containing gelatin and/or bovine albumin) responded predictably to well known cross-linking (formaldehyde) or coagulant (mercuric chloride) fixatives. Hexazonium pararosaniline solutions prevented the dissolution of protein gels in water only after 9 or more days of contact, during which time considerable swelling occurred. It is concluded that there is no evidence for a “fixative” action of hexazonium pararosaniline. The protective effect on frozen sections of unfixed tissue is attributable probably to the low pH of the solution. 相似文献
6.
MA Abo-El Seoud MM Sarhan AE Omar MM Helal 《Archives Of Phytopathology And Plant Protection》2013,46(3):175-184
Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens. 相似文献
7.
Sheree Yau Federico M Lauro Timothy J Williams Matthew Z DeMaere Mark V Brown John Rich John AE Gibson Ricardo Cavicchioli 《The ISME journal》2013,7(10):1944-1961
Organic Lake is a shallow, marine-derived hypersaline lake in the Vestfold Hills, Antarctica that has the highest reported concentration of dimethylsulfide (DMS) in a natural body of water. To determine the composition and functional potential of the microbial community and learn about the unusual sulfur chemistry in Organic Lake, shotgun metagenomics was performed on size-fractionated samples collected along a depth profile. Eucaryal phytoflagellates were the main photosynthetic organisms. Bacteria were dominated by the globally distributed heterotrophic taxa Marinobacter, Roseovarius and Psychroflexus. The dominance of heterotrophic degradation, coupled with low fixation potential, indicates possible net carbon loss. However, abundant marker genes for aerobic anoxygenic phototrophy, sulfur oxidation, rhodopsins and CO oxidation were also linked to the dominant heterotrophic bacteria, and indicate the use of photo- and lithoheterotrophy as mechanisms for conserving organic carbon. Similarly, a high genetic potential for the recycling of nitrogen compounds likely functions to retain fixed nitrogen in the lake. Dimethylsulfoniopropionate (DMSP) lyase genes were abundant, indicating that DMSP is a significant carbon and energy source. Unlike marine environments, DMSP demethylases were less abundant, indicating that DMSP cleavage is the likely source of high DMS concentration. DMSP cleavage, carbon mixotrophy (photoheterotrophy and lithoheterotrophy) and nitrogen remineralization by dominant Organic Lake bacteria are potentially important adaptations to nutrient constraints. In particular, carbon mixotrophy relieves the extent of carbon oxidation for energy production, allowing more carbon to be used for biosynthetic processes. The study sheds light on how the microbial community has adapted to this unique Antarctic lake environment. 相似文献
8.
Genetic background modifies inner ear and eye phenotypes of jag1 heterozygous mice 总被引:2,自引:0,他引:2
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Mice heterozygous for missense mutations of the Notch ligand Jagged1 (Jag1) exhibit head-shaking behavior indicative of an inner ear vestibular defect. In contrast, mice heterozygous for a targeted deletion of the Jag1 gene (Jag1del1) do not demonstrate obvious head-shaking behavior. To determine whether the differences in inner ear phenotypes were due to the types of Jag1 mutations or to differences in genetic background, we crossed Jag1del1 heterozygous mice onto the same genetic background as the missense mutants. This analysis revealed that variation of the Jag1 mutant inner ear phenotype is caused by genetic background differences and is not due to the type of Jag1 mutation. Genome scans of N2 backcross mice identified a significant modifier locus on chromosome 7, as well as a suggestive locus on chromosome 14. We also analyzed modifiers of an eye defect in Jag1del1 heterozygous mice from this same cross. 相似文献
9.
Reported in this work are the development of mass spectrometric immunoassay (MSIA) devices and methods for the qualitative analysis of IGF-1 and -2, and the rigorous quantification of IGF-1 from human plasma. A method involving addition of SDS in moderate concentration to unfractionated plasma for disrupting IGF/IGFBP complexes was initially developed. The method is suitable for the direct extraction of the IGFs and subsequent mass spectrometric analysis. Rat plasma, containing IGF-1 that is mass shifted from human IGF-1, was used as an internal reference standard (IRS) for the quantification of IGF-1 directly from human plasma. A standard curve with linear dynamic range of at least 2 orders of magnitude was constructed from serially diluted IGF-1 standards containing equal amounts of rat plasma. Using the standard curve, IGF-1 levels in plasma samples from eight individuals were determined. The limit of detection for the IGF-1 MSIA was also evaluated and established to be approximately 15 pM. The assay is rapid and can be performed in parallel via high-throughput robotics processing. Furthermore, the mass spectrometry aspect of the developed IGF-1 immunoassay offers a new dimension in the ongoing study of IGF-1 and related diseases. 相似文献
10.
Tat acetyl-acceptor lysines are important for human immunodeficiency virus type-1 replication 总被引:3,自引:0,他引:3
Brès V Kiernan R Emiliani S Benkirane M 《The Journal of biological chemistry》2002,277(25):22215-22221