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41.
42.
S Avidon SM Marr TA Bellingan KJ Esler OLF Weyl 《African Journal of Aquatic Science》2018,43(3):313-318
We evaluated the impact of non-native rainbow trout Oncorhynchus mykiss on a population of endemic Cedarberg ghost frog Heleophryne depressa in the upper Krom River (Olifants-Doring River Catchment, Cape Fold Ecoregion). We compared H. depressa abundance (using kick-sampling and underwater video analysis) and environmental conditions between sites above and below a waterfall that marks the upper distribution limit of O. mykiss. Heleophryne depressa abundance was significantly greater above the waterfall than that below it, and, because there was no significant difference in measured environmental variables, O. mykiss presence is identified as the most likely explanation for the observed decrease in H. depressa abundance. 相似文献
43.
Haploid plantlets derived by anther culture of Cucurbita pepo 总被引:5,自引:0,他引:5
Metwally E.I. Moustafa S.A. El-Sawy B.I. Shalaby T.A. 《Plant Cell, Tissue and Organ Culture》1998,52(3):171-176
This work was conducted to study the effect of sucrose and 2,4-D combinations on induction of haploid plants of a summer squash
cultivar through anther culture; therefore, sucrose was used at 30, 60, 90, 120 and 150 g l−1and 2, 4-D was used at 0.1, 1.0, 2.5 and 5.0 mg l−1on solid MS anther culture medium. Anthers at the mid or late uninucleate microspore stage without filament were excised from
sterilized buds and plated on 20 different induction media. The most plantlets resulted from the induction medium supplemented
with 150 g l−1sucrose and 5 mg l−12, 4-D. Root tips from 20 plantlets were cytologically examined under a light microscope. The results revealed ten diploid
(2n>= 2x= 40) and ten haploid (2n= x= 20) plants.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
44.
Production of haploid plants from in vitro culture of unpollinated ovules of Cucurbita pepo 总被引:9,自引:0,他引:9
Metwally E.I. Moustafa S.A. El-Sawy B.I. Haroun S.A. Shalaby T.A. 《Plant Cell, Tissue and Organ Culture》1998,52(3):117-121
Ovaries from squash plants (cv. Eskandarani) were picked one day before anthesis, and exposed to cold temperature (4 °C) for
0, 2, 4 and 8 days. The ovules were cultured on MS medium with 30 g l−1sucrose, 8 g l−1agar and supplemented with four concentrations of 2,4-D, i.e., 0.1, 1.0, 5 and 10 mg l−1. Then the dishes were incubated at 25 ± 1 °C under 16-h photoperiod for 4 weeks. After that ovules were transferred to growth
regulator free MS medium for 4 weeks. Data indicated that the most plantlets per 100 cultured ovules resulted from the ovule
of ovaries without cold treatment, when cultured in MS medium supplemented with 1 or 5 mg l−12,4-D. The cytological study revealed that one third of examined plants were haploid (2n = x = 20) and the others were double
haploid (2n = 2x = 40).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
45.
Hassan A. Abd El-Rehim Naeem M. El-Sawy El-Sayed A. Hegazy Ahmed M. Elbarbary 《Bioscience, biotechnology, and biochemistry》2013,77(6):997-1004
Ionizing radiation and oxidizing agent like H2O2 were used to degrade chitosan (CS) and its derivatives; N-maleoylchitosan (NMCS), and N-phthaloylchitosan (NPhCS). The structure changes were detected using gel permeation chromatography (GPC). The results revealed that ionizing radiation degraded CS, MNCS, NPhCS and altered their molecular weights and antioxidant activity. The higher the irradiation dose, the lower the molecular weight and the higher antioxidant activity. The addition of irradiated CS and NMCS to minced chicken resulted in highly significant reduction in malondialdehyde (MDA) content (50 and 70%, respectively) if compared with the control. The irradiated NMCS toxicity study did not show strong proliferative effect at small concentrations or cytotoxic effects at higher concentrations. The obtained results suggested that CS and NMCS could be used as natural antioxidant for improving the oxidative deterioration of minced chicken during refrigerated storage. 相似文献
46.
The Olifants River, a tributary of the Limpopo River system, is one of the most polluted rivers in South Africa. In May 2011 the concentrations of metals in fish muscle tissue from two impoundments, Loskop and Flag Boshielo dams, on the Olifants River were measured and a human health risk assessment conducted to investigate whether it was safe to consume Labeo rosae from these impoundments. Labeo rosae is one of the most common pan fish in these impoundments and is readily available to rural communities. Metals are accumulating in the muscle tissue of L. rosae even although the fish populations appear to be healthy. At Loskop Dam all L. rosae analysed exceeded the recommended hazard quotient (HQ) of 1 for antimony, and less than 50% exceeded that for lead. At Flag Boshielo Dam, the recommended HQ was exceeded for lead in less than 50% of L. rosae analysed, and more than 50% exceeded that for antimony. The weekly consumption of 150?g of L. rosae muscle tissue from these impoundments may pose an unacceptable health risk to rural communities. 相似文献
47.
Schenk S Kish DD He C El-Sawy T Chiffoleau E Chen C Chen C Wu Z Sandner S Gorbachev AV Fukamachi K Heeger PS Sayegh MH Turka LA Fairchild RL 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(6):3741-3748
Skin but not vascularized cardiac allografts from B6.H-2bm12 mice are acutely rejected by C57BL/6 recipients in response to the single class II MHC disparity. The underlying mechanisms preventing acute rejection of B6.H-2bm12 heart allografts by C57BL/6 recipients were investigated. B6.H-2bm12 heart allografts induced low levels of alloreactive effector T cell priming in C57BL/6 recipients, and this priming was accompanied by low-level cellular infiltration into the allograft that quickly resolved. Recipients with long-term-surviving heart allografts were unable to reject B6.H-2bm12 skin allografts, suggesting potential down-regulatory mechanisms induced by the cardiac allografts. Depletion of CD25+ cells from C57BL/6 recipients resulted in 15-fold increases in alloreactive T cell priming and in acute rejection of B6.H-2bm12 heart grafts. Similarly, reconstitution of B6.Rag(-/-) recipients with wild-type C57BL/6 splenocytes resulted in acute rejection of B6.H-2bm12 heart grafts only if CD25+ cells were depleted. These results indicate that acute rejection of single class II MHC-disparate B6.H-2bm12 heart allografts by C57BL/6 recipients is inhibited by the emergence of CD25+ regulatory cells that restrict the clonal expansion of alloreactive T cells. 相似文献
48.
Diabetes mellitus is a heterogeneous metabolic disorder characterized by hyperglycaemia resulting in defective insulin secretion,
resistance to insulin action or both. The use of biguanides, sulphonylurea and other drugs are valuable in the treatment of
diabetes mellitus; their use, however, is restricted by their limited action, pharmaco-kinetic properties, secondary failure
rates and side effects. Trigonella foenum-graecum, commonly known as fenugreek, is a plant that has been extensively used as a source of antidiabetic compounds from its seeds
and leaf extracts. Preliminary human trials and animal experiments suggest possible hypoglycaemic and anti-hyperlipedemic
properties of fenugreek seed powder taken orally. Our results show that the action of fenugreek in lowering blood glucose
levels is almost comparable to the effect of insulin. Combination with trace metal showed that vanadium had additive effects
and manganese had additive effects with insulin on in vitro system in control and diabetic animals of young and old ages using adipose tissue. The Trigonella and vanadium effects were studied in a number of tissues including liver, kidney, brain peripheral nerve, heart, red blood
cells and skeletal muscle. Addition of Trigonella to vanadium significantly removed the toxicity of vanadium when used to reduce blood glucose levels. Administration of the
various combinations of the antidiabetic compounds to diabetic animals was found to reverse most of the diabetic effects studied
at physiological, biochemical, histochemical and molecular levels. Results of the key enzymes of metabolic pathways have been
summarized together with glucose transporter, Glut-4 and insulin levels. Our findings illustrate and elucidate the antidiabetic/insulin
mimetic effects of Trigonella, manganese and vanadium. 相似文献
49.
Priya Chatterji Patrick A Williams Kelly A Whelan Fernando C Samper Sarah F Andres Lauren A Simon Louis R Parham Rei Mizuno Emma T Lundsmith David SM Lee Shun Liang HR
Sagara Wijeratne Stefanie Marti Lillian Chau Veronique Giroux Benjamin J Wilkins Gary D Wu Premal Shah Gian G Tartaglia Kathryn E Hamilton 《EMBO reports》2021,22(8)
Correction to: EMBO Reports (2019) 20: e47074. DOI 10.15252/embr.201847074 | Published online 6 May 2019The authors noticed that the control and disease labels had been inverted in their data analysis resulting in publication of incorrect data in Figure 1C. The corrected figure is displayed below. This change affects the conclusions as detailed below. The authors apologize for this error and any confusion it may have caused.In the legend of 1C, change from, “Differential gene expression analysis of pediatric ileal CD patient samples (n = 180) shows increased (> 4‐fold) IMP1 expression as compared to non‐inflammatory bowel disease (IBD) pediatric samples (n = 43)”.Open in a separate windowFigure 1CCorrected Open in a separate windowFigure 1COriginal To, "Differential gene expression analysis of pediatric ileal CD patient samples (n = 180) shows decreased (> 4‐fold) IMP1 expression as compared to non‐inflammatory bowel disease (IBD) pediatric samples (n = 43)”.In abstract, change from, “Here, we report increased IMP1 expression in patients with Crohn''s disease and ulcerative colitis”.To, “Here, we report increased IMP1 expression in adult patients with Crohn''s disease and ulcerative colitis”.In results, change from, “Consistent with these findings, analysis of published the Pediatric RISK Stratification Study (RISK) cohort of RNA‐sequencing data 38 from pediatric patients with Crohn''s disease (CD) patients revealed that IMP1 is upregulated significantly compared to control patients and that this effect is specific to IMP1 (i.e., other distinct isoforms, IMP2 and IMP3, are not changed; Fig 1C)”.To, “Contrary to our findings in colon tissue from adults, analysis of published RNA‐sequencing data from the Pediatric RISK Stratification Study (RISK) cohort of ileal tissue from children with Crohn’s disease (CD) 38 revealed that IMP1 is downregulated significantly compared to control patients in the RISK cohort and that this effect is specific to IMP1 (i.e., other distinct isoforms, IMP2 and IMP3, are not changed; Fig 1C)”.In discussion, change from, “Indeed, we report that IMP1 is upregulated in patients with Crohn''s disease and ulcerative colitis and that mice with Imp1 loss exhibit enhanced repair following DSS‐mediated damage”.To “Indeed, we report that IMP1 is upregulated in adult patients with Crohn''s disease and ulcerative colitis and that mice with Imp1 loss exhibit enhanced repair following DSS‐mediated damage”. 相似文献
50.