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71.
We are reporting a molecular comparative analysis of component 1 BBTV-DNA-R of an Egyptian isolate of (BBTV) and 30 different geographical isolates. DNA was extracted from BBTV-infected adult banana aphids collected from El-Qalubia Governorate, Egypt. Using specific primers the BBTV-DNA-R was amplified, cloned into a prokaryote vector, sequenced and a molecular comparative analysis of BBTV-DNA-R of this study and some overseas isolates of BBTV-infected banana plants was determined. Results showed that the component 1 consists of 1108 nts and contains a sequence of 69 nts representing the CR-SL of 31 nts. A CR-M (90 nts) at the position (972–1062) characterized with GC-rich sequence from nts 76 to 90 (average of 80% G + C) was found. Alignment results of BBTV DNA-R confirmed the presence of a number of conserved regions in all isolates. Large ORF of 861 nts at position 102 to 962 in the virion sense were detected. The predicted protein of this ORF consisted of 286 amino acids and had a molecular weight of 33.8 kDa. The DNA-phylogenetic analysis showed a percent identity of 98.0 and 97.9 between BBTV DNA-R and isolates of Pakistan (isolate TJ1) and Australia (isolate V1), respectively. The similarities between the gene product of Egyptian BBTV DNA-R and the 30 overseas isolates ranged from 93.7 to 99.0%. Differences in phylogenetic trees based on the entire sequence of BBTV DNA-R, CR-M and amino acid sequences confirmed the existence of two taxonomic groups of BBTV and the Egyptian isolate belongs to the south pacific group.  相似文献   
72.
Sadik , Sidki . (U. California, Davis.) Morphology of the curd of cauliflower. Amer. Jour. Bot. 49(3): 290–297. Illus. 1962.—The development of the curd and inflorescence of cauliflower, Brassica oleracea Linn., var. botrytis D.C., is described. The cultivars ‘Snowball M’ and ‘February-Early-March’ were studied. The curd has a nonfasciated and monopodial type of branching. Curd initiation of ‘Snowball M’ is not dependent on vernalization, but the curd of ‘February-Early-March’ and the floral primordia of both cultivars are initiated only after vernalization. Associated with flowering is the disruption of the curd by the elongation of some of the inflorescence branches. The initiation of leaves, branches, and floral primordia follows a 5 + 8 phyllotaxy throughout all stages of development. This system of phyllotaxy changes at the time of initiation of floral parts.  相似文献   
73.
The object of this study was the polymorphism of the ceruplasmin locus in different separate herds of cattle of the Pinzgan and the Red Polish breeds. The investigations carried out corroborated the hypothesis of the triallelic nature of this locus, which expands our knowledge and possibilities in this direction. The frequency of the alleles A, B and C in Red Polish cattle (n = 333) was 0,725; 0,026 and 0,249 respectively, being 0,920; 0,009 and 0,071 in the Pinzgan cattle (n = 369). An assumption is made about the greater value of proteins of a relatively high electrophoretic mobility as compared to those of a relatively low electrophoretic mobility.  相似文献   
74.
This study examined the downstream signaling whereby hyperglycemia may lead to myocardial fibrosis and apoptosis in the left ventricle of diabetic rats. The effects of sulfurous mineral water or sodium hydrosulfide (NaHS) as possible modulators were also examined. Sulfurous mineral water (as drinking water) and NaHS (14 μmol/kg/day, IP) were administered for 7 week to rats with streptozotocin (STZ)-induced diabetes. Hyperglycemia, overproduction of glycated hemoglobin (HbA1C) and serum decline in insulin, C-peptide and insulin like growth factor-I (IGF-I) were observed in diabetic rats. Up-regulation of gene expressions of nuclear factor (NF-κB), profibrogenic growth factor such as transforming growth factor-β1 (TGF-β1), matrix metalloproteniase-2 (MMP-2), procollagen-1 and Fas ligand (Fas-L) were observed in the left ventricle of diabetic rats. A linear positive correlation between TGF-β1 and MMP-2 was also detected in diabetic group. An increase in hydroxyproline level and a disturbance in oxidative balance were detected in heart of diabetic rats. Sulfurous mineral water and NaHS treatment possibly, by improving cardiac GSH level, counteracted the enhanced expression of NF-κB, the profibrogenic and apoptotic parameters. Histopathological examination was in accordance with the biochemical and molecular findings of this study. We suggest a novel therapeutic approach of sulfurous mineral water and exogenous supplementation of H2S in diabetic cardiomyopathy.  相似文献   
75.
The Ministry of Health in Iraq is undertaking a systematic programme to integrate mental health into primary care in order to increase population access to mental health care. This paper reports the evaluation of the delivery of a ten day interactive training programme to 20% of primary care centres across Iraq. The multistage evaluation included a pre- and post-test questionnaire to assess knowledge, attitudes and practice in health workers drawn from 143 health centres, a course evaluation questionnaire and, in a random sample of 41 clinics, direct observation of health workers skills and exit interviews of patients, comparing health workers who had received the training programme with those from the same clinics who had not received the training. Three hundred andseventeen health workersparticipated in the training, which achieved an improvement in test scores from 42.3% to 59%. Trained health workers were observed by research psychiatrists to have a higher level of excellent skills than the untrained health workers, and patient exit interviews also reported better skills in the trained rather than untrained health workers. The two week course has thus been able to achieve significant change, not only in knowledge, but also in subsequent demonstration of trained practitioners practical skills in the workplace. Furthermore, it has been possible to implement the course and the evaluation despite a complex conflict situation.  相似文献   
76.
77.
MicroRNAs (miRNAs) play critical regulatory roles in the physiological and pathological processes. The high stability of miRNAs in human serum represents attractive novel diagnostic biomarkers of clinical conditions. Several studies have shown that aberrant expression of miRNAs in human cancer including lung cancer, but little is known about their effects on some infectious lung diseases such as pulmonary tuberculosis (TB) and pneumonia. In this study, we investigated miRNA expression pattern in serum of Egyptian patients with lung cancer, TB, and pneumonia compared with matched healthy controls. Using microarray-based expression profiling followed by real-time quantitative polymerase chain reaction validation, we compared the levels of a series of circulating miRNAs (miR-21, miR-155, miR-182, and miR-197) in serum from patients with lung cancer (n = 65), pulmonary tuberculosis (n = 29), pneumonia (n = 29), and transudate (n = 16) compared with matched healthy controls (n = 37). MiRNA SNORD68 was the housekeeping endogenous control. We found that the serum levels of miR-21, miR-155, and miR-197 were significantly elevated in the patients with lung cancer and pneumonia whereas miR-182 and miR-197 levels were increased only in patients with lung cancer and TB, respectively, compared with controls. Receiver operating characteristic analysis revealed that miR-182, miR-155, and miR-197 have superior diagnostic potential in discriminating patients with lung cancer, pneumonia, and TB, respectively, from controls. Our results conclude that the differential expression of the four studied miRNAs can be potential non-invasive biomarkers for patients with lung cancer, TB and pneumonia.  相似文献   
78.
Oxygen‐derived free radicals have been implicated in the pathogenesis of renal injury after ischaemia–reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. To investigate whether treatment with either CAPE or alpha‐tocopherol modifies the levels of the endogenous indices of oxidant stress, we examined their effects on an in vivo model of renal ischaemia–reperfusion injury in rats. CAPE at 10 μmol kg?1 or alpha‐tocopherol at 10 mg kg?1 was administered intraperitoneally before reperfusion. Acute administration of both CAPE and alpha‐tocopherol altered the indices of oxidative stress differently in renal ischaemia–reperfusion injury. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
79.
High affinity and specificity are considered essential for affinity reagents and molecularly-targeted therapeutics, such as monoclonal antibodies. However, life''s own molecular and cellular machinery consists of lower affinity, highly multivalent interactions that are metastable, but easily reversible or displaceable. With this inspiration, we have developed a DNA-based reagent platform that uses massive avidity to achieve stable, but reversible specific recognition of polyvalent targets. We have previously selected these DNA reagents, termed DeNAno, against various cells and now we demonstrate that DeNAno specific for protein targets can also be selected. DeNAno were selected against streptavidin-, rituximab- and bevacizumab-coated beads. Binding was stable for weeks and unaffected by the presence of soluble target proteins, yet readily competed by natural or synthetic ligands of the target proteins. Thus DeNAno particles are a novel biomolecular recognition agent whose orthogonal use of avidity over affinity results in uniquely stable yet reversible binding interactions.  相似文献   
80.
The extensive invasive capacity of glioblastoma (GBM) makes it resistant to surgery, radiotherapy, and chemotherapy and thus makes it lethal. In vivo, GBM invasion is mediated by Rho GTPases through unidentified downstream effectors. Mammalian Diaphanous (mDia) family formins are Rho-directed effectors that regulate the F-actin cytoskeleton to support tumor cell motility. Historically, anti-invasion strategies focused upon mDia inhibition, whereas activation remained unexplored. The recent development of small molecules directly inhibiting or activating mDia-driven F-actin assembly that supports motility allows for exploration of their role in GBM. We used the formin inhibitor SMIFH2 and mDia agonists IMM-01/-02 and mDia2-DAD peptides, which disrupt autoinhibition, to examine the roles of mDia inactivation versus activation in GBM cell migration and invasion in vitro and in an ex vivo brain slice invasion model. Inhibiting mDia suppressed directional migration and spheroid invasion while preserving intrinsic random migration. mDia agonism abrogated both random intrinsic and directional migration and halted U87 spheroid invasion in ex vivo brain slices. Thus mDia agonism is a superior GBM anti-invasion strategy. We conclude that formin agonism impedes the most dangerous GBM component—tumor spread into surrounding healthy tissue. Formin activation impairs novel aspects of transformed cells and informs the development of anti-GBM invasion strategies.  相似文献   
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