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131.
We previously reported a cDNA for vitellogenin (Vg) from the cockroach, Leucophaea maderae (Lm). In the present study, we identified another cDNA encoding a second Vg (Vg2) having stretches of amino acid sequences different from the first one, Vg1, reported earlier. The complete nucleotide sequence of Vg2 consisted of 5,915 bp, which encoded a primary protein of 1,911 residues including a 16-residue putative signal peptide. The regions different in both Vg precursors (Pro-Vg1 and pro-Vg2) were four in number, and two, relatively longer, existed at the carboxy terminal. The presence of two Vg-related cDNAs was confirmed by sequencing of RT-PCR products generated using primers designed based on the common sequences flanking the regions different in amino acid sequences. Both forms were transcribed since they could be amplified on mRNA from fat bodies of different individual females. Southern blot analysis of digested genomic DNA revealed the existence of two Vg-related genes in L. maderae indicating that each Vg cDNA originated from a separate gene. Also, the immunoblot analysis using antibodies generated against peptides unique to both Vg1 and Vg2 probed the same antigen in the same individual, suggesting LmVg to be a product coded by two different Vg precursors. Both Vg primary products showed 96% similarity at an amino acid level. Compared to other insect Vgs, Vg2 showed a slightly higher (1-2%) similarity than Vg1. We previously reported, based on amino-terminal sequence analysis, that L. maderae pro-Vg was cleaved into four subunit polypeptides (112-, 100-, 92-, and 55-kD), which were deposited in the egg as four respective vitellin (Vn) polypeptides. We show now based on immunoblot analysis that the 112-kD polypeptide is further cleaved, near the C-terminus, to an 87-kD polypeptide before it is secreted into the hemolymph. Both the L. maderae Vgs were compared with each other and with other insect Vgs and the processing pattern is discussed.  相似文献   
132.

Background

Acute coronary syndromes (ACS) are complex and polygenic diseases which are a real problem of public health. These syndromes require multidisciplinary studies to understand the pathogenesis mechanisms and metabolic interactions between different risk factors.This study aimed to explore the variation of two coronary risk parameters not mentioned by Framingham cohorts, hyperhomocysteinemia and endothelin-1 (ET-1) in Tunisian coronary and the study of the variation of these parameters based on various cardiac risk factors and metabolic relationship between them.To 157 coronary and 142 healthy subjects, the concentration of homocysteine was quantified by fluorescence polarization immunoassay; the concentration of ET-1 was measured by an analytical technique, the High Performance Liquid Chromatography (HPLC) coupled with mass spectrometry.

Results

Our study showed that homocysteine and ET-1 were significantly higher in patients compared to healthy subjects (24.40 ± 12.5 μmol/L vs 7.44 ± 2.5 μmol/L p <0.00001) for homocysteine and (15.2 ± 5.3 nmol/L vs 7.1 ± 2.7 nmol/L, p <0.00001) for ET-1. On the other hand, homocysteine varies according to tobacco and diabetes while ET-1 depends on the sex, hypertension, smoking, obesity and dyslipidemia and a statistically negative correlation was shown between homocysteine and ET-1 in coronary patients (r = −0.66 p <0.00001).

Conclusion

The study of the variation of these two parameters in coronary patients and metabolic exploration of the relationship between homocysteine and ET-1 according to various risk factors and the interactions between themselves facilitates the decision of therapeutic treatment.  相似文献   
133.
Thiopurine methyltransferase (TPMT) gene polymorphism regulates thiopurine therapeutic efficacy and toxicity. The aim of this study was to determine the influence of TPMT gene polymorphism in Egyptian children with acute lymphoblastic leukaemia (ALL). Sixty-four patients with ALL, T lineage (27%) and pre-B phenotype (73%), who were treated with BFM 90 or CCG 1991 standard risk protocol, and who also experienced myleosuppresion toxicity and required interruption and/or modification of thiopurine chemotherapy were recruited over a year period. Thirty-two patients were on maintenance and another 32 completed their chemotherapy. Seventy healthy age-matched and sex-matched children served as controls. They were subjected to clinical assessment, haematological panel investigations and TPMT gene polymorphism for G238C, G460A and A719G alleles assessment using PCR followed by RFLP analysis. Although none of the studied patients had the mutant TPMT variant alleles, myelosuppression toxicity in the form of different degree of neutropenia was detected in all patients. As a result of myelosuppression toxicity, most of the patients needed 6-MP dose modification either once (53.1%), twice (15.6%), or \(\ge \) thrice (25.1%) during their maintenance course and 96.9% of the patients required to stop 6-MP for less than a week (62.5%), up to 2 weeks (28.1%), or \(> 2\) weeks (6.3%). Patients also developed infection who mostly (71%) needed hospitalization. None of the studied G238C, G460A and A719G TPMT variant alleles were detected. Infections and febrile neutropenia were common causes of 6-PM dose modification and interruption.  相似文献   
134.
This study aimed at reinvestigating the controversial contribution of Notch signaling to megakaryocytic lineage development. For that purpose, we combined colony assays and single cells progeny analyses of purified megakaryocyte-erythroid progenitors (MEP) after short-term cultures on recombinant Notch ligand rDLL1. We showed that Notch activation stimulated the SCF-dependent and preferential amplification of Kit+ erythroid and bipotent progenitors while favoring commitment towards the erythroid at the expense of megakaryocytic lineage. Interestingly, we also identified a CD9High MEP subset that spontaneously generated almost exclusively megakaryocytic progeny mainly composed of single megakaryocytes. We showed that Notch activation decreased the extent of polyploidization and maturation of megakaryocytes, increased the size of megakaryocytic colonies and surprisingly restored the generation of erythroid and mixed colonies by this CD9High MEP subset. Importantly, the size increase of megakaryocytic colonies occurred at the expense of the production of single megakaryocytes and the restoration of colonies of alternative lineages occurred at the expense of the whole megakaryocytic progeny. Altogether, these results indicate that Notch activation is able to extend the number of divisions of MK-committed CD9High MEPs before terminal maturation while allowing a fraction of them to generate alternative lineages. This unexpected plasticity of MK-committed progenitors revealed upon Notch activation helps to better understand the functional promiscuity between megakaryocytic lineage and hematopoietic stem cells.  相似文献   
135.
This study was conducted on 100 one-day-old broiler chicks to evaluate the effect of Poulvac E. coli vaccine in reduction of clinical signs and complications after concurrent infectious bronchitis virus (variant 02) and virulent E. coli O78 challenges. The birds were evaluated for clinical signs, mortality for 7?days post-infection, PM lesion score, average body weight and serological evaluation. Re-isolation and RT-PCR for the challenging infectious bronchitis virus (IBV) variant 02 were conducted thereafter. The results showed that the Poulvac E. coli at one-day old chicks in the presence of co-infection with virulent E. coli and IBV variant 02 provides better body weight gain at 35?days than the other groups. The challenge with IBV variant 02 alone in non-vaccinated birds doesn’t give any mortality; this indicated that the severity of IBV variant 02 increased by the presence of co-infection with Avian Pathogenic E. coli (APEc). The mortality percentage associated with both E. coli and IBV variant 02 infections in the none vaccinated group by Poulvac E. coli was 25% while this percentage was 10% of the vaccinated group. The Poulvac E. coli is not negatively affecting the immune response against different concurrent viral vaccines like Infectious bursal disease (IBD), and moreover, it improves the immune response against some others like Newcastle disease virus (NDV), Avian Influenza (AI) H5 and IBV.  相似文献   
136.
The aim of this study was to assess the efficacy of quantitative ultrasound imaging in characterizing cancer cell death caused by enhanced radiation treatments. This investigation focused on developing this ultrasound modality as an imaging-based non-invasive method that can be used to monitor therapeutic ultrasound and radiation effects. High-frequency (25 MHz) ultrasound was used to image tumor responses caused by ultrasound-stimulated microbubbles in combination with radiation. Human prostate xenografts grown in severe combined immunodeficiency (SCID) mice were treated using 8, 80, or 1000 µL/kg of microbubbles stimulated with ultrasound at 250, 570, or 750 kPa, and exposed to 0, 2, or 8 Gy of radiation. Tumors were imaged prior to treatment and 24 hours after treatment. Spectral analysis of images acquired from treated tumors revealed overall increases in ultrasound backscatter intensity and the spectral intercept parameter. The increase in backscatter intensity compared to the control ranged from 1.9±1.6 dB for the clinical imaging dose of microbubbles (8 µL/kg, 250 kPa, 2 Gy) to 7.0±4.1 dB for the most extreme treatment condition (1000 µL/kg, 750 kPa, 8 Gy). In parallel, in situ end-labelling (ISEL) staining, ceramide, and cyclophilin A staining demonstrated increases in cell death due to DNA fragmentation, ceramide-mediated apoptosis, and release of cyclophilin A as a result of cell membrane permeabilization, respectively. Quantitative ultrasound results indicated changes that paralleled increases in cell death observed from histology analyses supporting its use for non-invasive monitoring of cancer treatment outcomes.  相似文献   
137.
Myrrh is an herbal product that has been used since ancient ages for traditional medication and other purposes. The revolution of myrrh as an antiparasitic agent in Egypt began in the 1990s through scientific evidence-based research. The human trematode infections in Egypt were the main focus of research with stories of success and disagreement, at times. The present paper reviewed the antiparasitary activity of myrrh with stress on its possible mode of action, its safety, efficacy and effectiveness on trematode infections in experimental studies and clinical trials in Egypt as well as its molluscicidal effects on the intermediate hosts of trematodes.  相似文献   
138.
To analyze alogliptin in its pharmaceutical dosage forms and human plasma, a sensitive, inexpensive, simple, and precise spectrofluorimetric method was developed and tested. This method was also used to investigate the drug’s pharmacokinetic behaviour in the blood of rats. This was based on the Hantzsch reaction, which produces yellowish luminous products that can be detected spectrofluorometrically at 480 and 415 nm for emission and excitation, respectively, when the primary amine group in the examined drug reacts with acetylacetone and formaldehyde. Several experimental parameters that affect the reaction product's development and stability were explored and improved. The curve of fluorescence and concentration for alogliptin was linear in the concentration range 0.05–3.60 μg ml−1. The proposed approach was validated according to International Council for Harmonization criteria. The method was successfully utilized to evaluate the examined drug in dose formulations and spiked human plasma with high accuracy.  相似文献   
139.
INTRODUCTION: Quantitative ultrasound parameters based on form factor models were investigated as potential biomarkers of cell death in breast tumor (MDA-231) xenografts treated with chemotherapy. METHODS: Ultrasound backscatter radiofrequency data were acquired from MDA-231 breast cancer tumor–bearing mice (n = 20) before and after the administration of chemotherapy drugs at two ultrasound frequencies: 7 MHz and 20 MHz. Radiofrequency spectral analysis involved estimating the backscatter coefficient from regions of interest in the center of the tumor, to which form factor models were fitted, resulting in estimates of average scatterer diameter and average acoustic concentration (AAC). RESULTS: The ∆AAC parameter extracted from the spherical Gaussian model was found to be the most effective cell death biomarker (at the lower frequency range, r2 = 0.40). At both frequencies, AAC in the treated tumors increased significantly (P = .026 and .035 at low and high frequencies, respectively) 24 hours after treatment compared with control tumors. Furthermore, stepwise multiple linear regression analysis of the low-frequency data revealed that a multiparameter quantitative ultrasound model was strongly correlated to cell death determined histologically posttreatment (r2 = 0.74). CONCLUSION: The Gaussian form factor model–based scattering parameters can potentially be used to track the extent of cell death at clinically relevant frequencies (7 MHz). The 20-MHz results agreed with previous findings in which parameters related to the backscatter intensity (i.e., AAC) increased with cell death. The findings suggested that, in addition to the backscatter coefficient parameter ∆AAC, biological features including tumor heterogeneity and initial tumor volume were important factors in the prediction of cell death response.  相似文献   
140.
BackgroundPsoriasis is a chronic skin disorder manifested by recurrent episodes of scaly, red, itchy skin patches that occur within apparently normal skin.ObjectivesThis study was performed to detect the expression of serum and tissue (lesion and non-lesion) LncRNA MALAT-1 and MiRNA-9 that might be used as biomarkers for psoriasis.MethodsBlood samples were obtained from 60 psoriasis patients and 40 controls, as well as 4 mm punch biopsy from lesional and non lesional skin of psoriatic patient and normal skin of healthy controls. Expression of LncRNA MALAT-1 and miRNNA-9 in serum and tissues was detected by real time qRT-PCR.Resultsa statistically significant increase in the expression of MALAT-1 in lesional and non-lesional skin and serum of psoriatic patients in comparison to controls were detected. Moreover, there was statistically significant increase in serum MiRNA-9 in patients in comparison to controls, while its tissue level was significantly lower in patients.ConclusionThis study highlights the dysregulation of LncRNA MALAT-1 and miRNA-9 in psoriasis. Elevated expression of MALAT-1 in lesional skin of psoriatic patients compared to non-lesional skin may possibly contribute to the development of psoriatic plaques.  相似文献   
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