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1.
Journal of Plant Growth Regulation - The salinization of agriculture soils over the globe has become one of the most devastating stresses and is significantly limiting cultivated land area, and...  相似文献   
2.
Hemagglutinin–neuraminidase (HN) protein besides its mediation in viral pathogenesis, is composed of various antigenic sites which stimulate production of host’s antibodies. Thus, application of this protein in serological tests and vaccination plays a major role in biosecurity and control programs. In the present study, we designed a recombinant HN protein containing different neutralizing antigenic sites with velogenic patterns, and sub-cloned it into pET-43.1a+ expression vector. The expression of NusA-HN recombinant protein was induced. Affinity chromatography protein purification using HisPur? Ni–NTA was then conducted. Moreover, we performed western-blot technique using HRP-conjugated Anti His-Tag. Results revealed that following induction of recombinant protein, two distinct bands of HN-61 kDa and NusA-63 kDa were purified and identified by western-blotting. We recommend further analysis should be carried out to determine the functional role of this recombinant protein in enzyme-linked immunosorbent assays for Newcastle disease diagnosis. This HN protein containing multi neutralizing antigenic sites might also be applicable in vaccination programs to increase vaccines potency.  相似文献   
3.

Background and aims

Extensive worldwide dryland degradation calls for identification of functional traits critical to dryland plant performance and restoration outcomes. Most trait examination has focused on drought tolerance, although most dryland systems are water and nutrient co-limited. We studied how drought impacts both plant water relations and nitrogen (N) nutrition.

Methods

We grew a suite of grasses common to the Intermountain West under both well-watered and drought conditions in the greenhouse. These grasses represented three congener pairs (Agropyron, Elymus, Festuca) differing in their habitat of origin (“wetter” or “drier”). We measured growth, water relations, N resorption efficiency and proficiency and photosynthetic N use efficiency in response to drought.

Results

Drought decreased growth and physiological function in the suite of grasses studied, including a negative impact on plant N resorption efficiency and proficiency. This effect on resorption increased over the course of the growing season. Evolutionary history constrained species responses to treatment, with genera varying in the magnitude of their response to drought conditions. Surprisingly, habitat of origin influenced few trait responses.

Conclusions

Drought impacted plant N conservation, although these responses also were constrained by evolutionary history. Future plant development programs should consider drought tolerance not only from the perspective of water relations but also plant mineral nutrition, taking into account the role of phylogeny.  相似文献   
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Chronic alcohol ingestion causes sexual dysfunction, impairs sperm motility and fertility, and changes semen quality. Considering the key role of epididymis in sperm development, the aim of the present study was to evaluate the effects of long‐term ethanol consumption on epididymis changes, including alterations in β‐defensin isoform gene expression, oxidative stress, and pathological changes, such as cell proliferation and fibrosis in the epididymis of rats. In this study, male Wistar rats were equally divided into control and ethanol (4.5 g/kg BW) groups. After six weeks of treatment, the results revealed the proliferation of epididymis cells, fibrosis in the epididymis tissue, and a significant rise in the level of 8‐OHdG and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in the ethanol group, compared with the control group. Moreover, the ethanol group showed an increase in the gene expression of epididymal β‐defensin isoforms 15 and 21 and a reduction in the gene expression of β‐defensin isoforms 27 and 30, compared with the controls. These findings indicate that ethanol‐induced epididymal damage and sperm abnormalities might be partly associated with changes in β‐defensin isoforms and epididymal structure, mediated by the increased activities of 8‐OHdG and NADPH oxidase.  相似文献   
6.
There is information regarding the rates of gastric cancer (GC) in different populations and the important role of Helicobacter pylori in GC development; however, no comprehensive study has yet been performed to investigate the prevalence of GC in H. pylori–infected patients. PubMed, Embase, and Cochrane Library through January 1, 2000 were searched without language restrictions. Quality of included studies was assessed with a critical appraisal checklist recommended by the Joanna Briggs Institute. All of the analyses were conducted using Comprehensive Meta-Analysis Software Version 2.0 and Stata 14.0. Forty-four studies from 17 countries were included. The pooled frequency of GC was 17.4% (95% confidence interval: 16.4–18.5) in H. pylori–infected population. The frequency of GC among H. pylori–infected population varied markedly across countries. The highest rate of GC was observed in H. pylori–infected individuals from Asian countries. The frequency of GC was relatively high in H. pylori–infected population in the world. However, the eradication of H. pylori might be a promising strategy for GC prevention, especially in high-risk populations such as Asian countries.  相似文献   
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Calcitonin (CT) is one of the factors affecting the embryo implantation, but its effects on the implantation window have not been fully investigated. The current study investigated the effects of CT on the endometrium receptivity by morphological study and evaluation of leukemia inhibitory factor (LIF), mucin 1 (Muc-1), and microRNA (miRNA) Let-7a in the ovarian stimulation and the normal ovarian cycle. Then the mechanism of the CT effects through the mammalian target of rapamycin (mTOR) signaling pathway was studied by using PP242. A total of 64 BALB/c mice were divided into the normal ovarian cycle and ovarian stimulation groups. Each group consisted of four subgroups: control, calcitonin, PP242, and calcitonin+PP242. CT and PP242 were injected on the fourth of pregnancy into the mice and 24 hr later all the mice were killed. The uterine tissue samples were used for morphological analysis, and endometrial cells were mechanically isolated for evaluation of gene and protein expression. The results showed that ovarian stimulation induced mTOR phosphorylation as well as increased expression of the Let-7a miRNA. In addition, CT injection increased the expression of LIF and miRNA Let-7a in ovarian stimulation similar to that in normal ovarian cycles. However, injection of PP242 reduced expression of miRNA Let-7a and increased Muc-1 expression in ovarian stimulation group. In conclusion, the administration of CT improved endometrial receptivity in mice. This phenomenon occurred by upregulation of LIF, miRNA Let-7a and downregulation of Muc-1 via mTOR signaling pathway.  相似文献   
9.
Gastric adenocarcinoma is usually diagnosed in late stages, necessitating the use of different therapeutic modalities. Currently, antibody-based therapies have also been approved through with limited clinical efficacy. Reinforcing antibody-based immunotherapy by using chimeric antigen receptor (CAR) T cells may enhance the approach. However, the cells can cause severe on-target and off-tumor toxicities owing to their higher sensitivity to low-level antigen expressions. To address the need for safe and reliable targets, we made a bioinformatics pipeline by which we screened overexpressed genes in the disease for off-tumor sites in many normal tissues. Our inspection showed that MSLN (Mesothelin), ANTXR1 (TEM8), and MUC3A are the probable targets of CAR T cell therapy in gastric adenocarcinoma. The proposed antigenic targets might respond to the need to simultaneously target multiple antigens in a tumor matrix to prevent resistance.  相似文献   
10.
Calprotectin is member of the S-100 protein family with a wide plethora of intra-and extracellular functions. Anticancer activities, antimicrobial effects and being a qualified disease marker are among the compelling features of this protein to be used as a pharmaceutical agent. However, there are several impediments to applications of protein pharmaceuticals including: proteolytic degradation, short circulating half-life, low solubility and immunogenicity. Pegylation is a common bioconjugation polymer capable of overcoming these drawbacks. Recombinant expression and purification of calprotectin along with its pegylation would result in enhanced pharmaco-dynamic and pharmacokinetic properties. Our florescence spectroscopy and far Ultraviolet-optical density results indicate that pegylation altered the physical and structural properties of the calprotectin to become in a more stable and functionally active state. Due to enhanced pharmacodynamic and pharmacokinetic properties of the calprotectin via pegylation, this study would pave the way for better in vitro and in vivo validations of calprotectin applications in medical practice.  相似文献   
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