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421.

Aim

To evaluate the process of placing DNR order in elderly cancer patients in practice and analysis of physician perspectives on the issue.

Background

Decision not to resuscitate (DNR/DNAR) is part of practice in elderly cancer care. Physicians issue such orders when a patient is suffering from irreversible disease and the patient''s life is coming to an end. Modern practice emphasises the need of communication with the patients and their relatives while issuing a DNR. The decision making process of placing DNR can be quite daunting. The moral and ethical dimensions surrounding such a decision make it a contentious topic.

Materials and methods

We searched the literature to find relevant works that would help physicians and especially the junior health care staff in dealing with the complexities. In this article, we discuss the issues that physicians encounter whilst dealing with a DNR order in elderly cancer patients.

Results

There are no objective adjuncts or guidelines directed towards the approach of placing a DNR in elderly cancer patients. Better communication with the patients and relatives when making such decision remains a very important aspect of a DNR decision. Most health care staff find themselves ill equipped to deal with such situation. Active training and briefing of junior staff would help them deal better with the stresses involved in this process.

Conclusion

There are complex psychosocial, medical, ethical and emotive aspects associated with placing a DNR order. Patients and their loved ones and the junior staff involved in the care of patient need early communication and briefing for better acceptance of DNR. Studies that could devise or identify tools or recommendations would be welcome.  相似文献   
422.
Abstract

Melanoma is the most deadly and life-threatening form of skin cancer with progressively higher rates of incidence worldwide. The objective of the present investigation is to develop and to statistically optimize and characterize curcumin (CUR) loaded ethosomes for treatment of melanoma. A two factor, three level (32) factorial design approach was employed for the optimization of ethosomes. The prepared ethosomes were evaluated for size, zeta potential, entrapment efficiency, in vitro skin permeation and deposition ability. The optimized ethosomal formulation was evaluated for in vitro cytotoxicity and cellular uptake studies using A375 human melanoma cells. The optimized formulation has imperfect round shaped unilamellar structures with a mean vesicle size of 247?±?5.25?nm and an entrapment efficiency of 92.24?±?0.20%. The in vitro skin permeation studies proved the superiority of ethosomes over the traditional liposomes in terms of the amount of drug permeated and deposited in skin layers. Fluorescence microscopy showed the enhanced penetration of ethosomes into the deeper layers of the skin. In vitro cytotoxicity and cellular uptake studies revealed that curcumin ethosomes have significantly improved cytotoxicity and cellular uptake in A375 human melanoma cell lines. The colony formation assay results showed that curcumin ethosomes have a superior antiproliferative effect as they effectively inhibit the clonogenic ability of A375 cells. The flow cytometry results indicate that curcumin ethosomes induce cell death in A375 cells by apoptosis mechanism. The present study provides a strong rationale and motivation for further investigation of newly developed curcumin ethosomes as a potential therapeutic strategy for melanoma treatment.  相似文献   
423.
In the present study, six arsenic-resistant strains previously isolated were tested for their plant growth promoting characteristics and heavy metal resistance, in order to choose one model strain as an inoculum for sunflower plants in pot experiments. The aim was to investigate the effect of arsenic-resistant strain on sunflower growth and on arsenic uptake from arsenic contaminated soil. Based on plant growth promoting characteristics and heavy metal resistance, Alcaligenes sp. strain Dhal-L was chosen as an inoculum. Beside the ability to reduce arsenate to arsenite via an Ars operon, the strain exhibited 1-amino-cyclopropane-1-carboxylic acid deaminase activity and it was also able to produce siderophore and indole acetic acid. Pot experiments were conducted with an agricultural soil contaminated with arsenic (214 mg kg?1). A real time PCR method was set up based on the quantification of ACR3(2) type of arsenite efflux pump carried by Alcaligenes sp. strain Dhal-L, in order to monitor presence and colonisation of the strain in the bulk and rhizospheric soil. As a result of strain inoculation, arsenic uptake by plants was increased by 53 %, whereas ACR3(2) gene copy number in rhizospheric soil was 100 times higher in inoculated than in control pots, indicating the colonisation of strain. The results indicated that the presence of arsenate reducing strains in the rhizosphere of sunflower influences arsenic mobilization and promotes arsenic uptake by plant.  相似文献   
424.
A novel series of N-aryl-3,4-dihydro-1′H-spiro[chromene-2,4′-piperidine]-1′-carboxamides was identified as transient receptor potential melastatin 8 (TRPM8) channel blockers through analogue-based rational design, synthesis and screening. Details of the synthesis, effect of aryl groups and their substituents on in-vitro potency were studied. The effects of selected functional groups on the 4-position of the chromene ring were also studied, which showed interesting results. The 4-hydroxy derivatives showed excellent potency and selectivity. Optical resolution and screening of alcohols revealed that (R)-(–)-isomers were in general more potent than the corresponding (S)-(+)-isomers. The isomer (R)-(–)-10e (IC50: 8.9 nM) showed a good pharmacokinetic profile upon oral dosing at 10 mg/kg in Sprague–Dawley (SD) rats. The compound (R)-(–)-10e also showed excellent efficacy in relevant rodent models of neuropathic pain.  相似文献   
425.
Earlier we identified wheat (Triticum aestivum L.) chromosome 3A as a major determinant of grain yield and its component traits. In the present study, a high-density genetic linkage map of 81 chromosome 3A-specific markers was developed to increase the precision of previously identified yield component QTLs, and to map QTLs for biomass-related traits. Many of the previously identified QTLs for yield and its component traits were confirmed and were localized to narrower intervals. Four novel QTLs one each for shoot biomass (Xcfa2262-Xbcd366), total biomass (wPt2740-Xcfa2076), kernels/spike (KPS) (Xwmc664-Xbarc67), and Pseudocercosporella induced lodging (PsIL) were also detected. The major QTLs identified for grain yield (GY), KPS, grain volume weight (GVWT) and spikes per square meter (SPSM) respectively explained 23.2%, 24.2%, 20.5% and 20.2% of the phenotypic variation. Comparison of the genetic map with the integrated physical map allowed estimation of recombination frequency in the regions of interest and suggested that QTLs for grain yield detected in the marker intervals Xcdo549-Xbarc310 and Xpsp3047-Xbarc356 reside in the high-recombination regions, thus should be amenable to map-based cloning. On the other hand, QTLs for KPS and SPSM flanked by markers Xwmc664 and Xwmc489 mapped in the low-recombination region thus are not suitable for map-based cloning. Comparisons with the rice (Oryza sativa L.) genomic DNA sequence identified 11 candidate genes (CGs) for yield and yield related QTLs of which chromosomal location of two (CKX2 and GID2-like) was confirmed using wheat aneuploids. This study provides necessary information to perform high-resolution mapping for map-based cloning and for CG-based cloning of yield QTLs.  相似文献   
426.
The mosquito Culex quinquefasciatus is a ubiquitous species that serves as a major vector for west nile virus and lymphatic filariasis. Ingestion of bloodmeal by females triggers a series of physiological processes in the midgut and also exposes them to infection by these pathogens. The bacteria normally harbored in the midgut are known to influence physiology and can also alter the response to various pathogens. The midgut bacteria in female Cx. quinquefasciatus mosquitoes collected over a large geographical area from India was studied. Examination of 16S ribosomal DNA amplicons from culturable microflora revealed the presence of 83 bacterial species belonging to 31 bacterial genera. All of these species belong to three phyla i.e. Proteobacteria, Firmicutes and Actinobacteria. Phylum Proteobacteria was the most dominant phylum (37 species), followed by Firmicutes (33 species) and Actinobacteria (13 species). Phylum Proteobacteria, was dominated by members of γ-proteobacteria class. The genus Staphylococcus was the largest genus represented by 11 species whereas Enterobacter was the most prevalent genus and recovered from all the field stations except Leh. Highest bacterial prevalence was observed from Bhuj (22 species) followed by Nagrota (18 species), Masimpur (18 species) and Hathigarh (16 species). Whereas, least species were observed from Leh (8 species). It has been observed that individual mosquito harbor extremely diverse gut bacteria and have very small overlap bacterial taxa in their gut. This variation in midgut microbiota may be one of the factors responsible for variation in disease transmission rates or vector competence within mosquito population. The present data strongly encourage further investigations to verify the potential role of the detected bacteria in mosquito for the transmission of lymphatic filariasis and west nile virus. To the best of our knowledge this is the first study on midgut microbiota of wild Cx. quinquefasciatus from over a large geographical area.  相似文献   
427.
Microspores can be induced to develop homozygous doubled haploid plants in a single generation. In the present experiments androgenic microspores of wheat have been genetically transformed and developed into mature homozygous transgenic plants. Two different transformation techniques were investigated, one employing electroporation and the other co-cultivation with Agrobacterium tumefaciens. Different tissue culture and transfection conditions were tested on nine different wheat cultivars using four different constructs. A total of 19 fertile transformants in five genotypes from four market classes of common wheat were recovered by the two procedures. PCR followed by DNA sequencing of the products, Southern blot analyses and bio/histo-chemical and histological assays of the recombinant enzymes confirmed the presence of the transgenes in the T0 transformants and their stable inheritance in homozygous T1∶2 doubled haploid progenies. Several decisive factors determining the transformation and regeneration efficiency with the two procedures were determined: (i) pretreatment of immature spikes with CuSO4 solution (500 mg/L) at 4°C for 10 days; (ii) electroporation of plasmid DNA in enlarged microspores by a single pulse of ∼375 V; (iii) induction of microspores after transfection at 28°C in NPB-99 medium and regeneration at 26°C in MMS5 medium; (iv) co-cultivation with Agrobacterium AGL-1 cells for transfer of plasmid T-DNA into microspores at day 0 for <24 hours; and (v) elimination of AGL-1 cells after co-cultivation with timentin (200–400 mg/L).  相似文献   
428.

Objective:

To utilize data from routine CT scans to quantify obesity in polytrauma patients without the need to obtain a height and weight.

Design and Methods:

We utilized a comprehensive database including multidetector CT thoracoabdominal images of all polytrauma patients admitted to a Level 1 trauma center. One thousand one hundred seventy‐four patients were reviewed from 2006 to 2008 and of these, 162 had previous documentation of Body Mass Index (BMI) or height and weight measurements as an outpatient within 6 months of trauma activation and with a truncal girth smaller than the scanning area of the CT machine. Truncal Adiposity Volume (TAV) was calculated from three dimensional reconstructions (3DRs) of the CT scans of the thorax and abdomen obtained in the emergency department.

Results:

Statistical analysis yielded a fairly good correlation between TAV and BMI (correlation coefficient = 0.77; p‐value < 0.0001). The intra‐observer and inter‐observer correlations in measuring TAV were high; 0.99 and 0.98 respectively. A linear regression equation of BMI on TAV was estimated and it had a form: 3DR BMI = 20.81+0.00064×TAV. In conclusion, TAV provides a reproducible means of evaluating obesity in trauma patients from routinely obtained CT scans.

Conclusions:

The TAV eliminates the often problematic task of obtaining a height and weight in a trauma patient and it correlates fairly well with the most commonly used clinical method of quantifying patient adiposity, BMI. This method may provide a more direct measurement of adiposity than does BMI, and holds promise for improving trauma care and research in the obese patient.  相似文献   
429.

Background

Genetic studies reveal that vpu is one of the most variable regions in HIV-1 genome. Functional studies have been carried out mostly with Vpu derived from laboratory adapted subtype B pNL 4-3 virus. The rationale of this study was to characterize genetic variations that are present in the vpu gene from HIV-1 infected individuals from North-India (Punjab/Haryana) and determine their functional relevance.

Methods

Functionally intact vpu gene variants were PCR amplified from genomic DNA of HIV-1 infected individuals. These variants were then subjected to genetic analysis and unique representative variants were cloned under CMV promoter containing expression vector as well as into pNL 4-3 HIV-1 virus for intracellular expression studies. These variants were characterized with respect to their ability to promote virus release as well as cell death.

Results

Based on phylogenetic analysis and extensive polymorphisms with respect to consensus Vpu B and C, we were able to arbitrarily assign variants into two major groups (B and C). The group B variants always showed significantly higher virus release activity and exhibited moderate levels of cell death. On the other hand, group C variants displayed lower virus release activity but greater cell death potential. Interestingly, Vpu variants with a natural S61A mutation showed greater intracellular stability. These variants also exhibited significant reduction in their intracellular ubiquitination and caused greater virus release. Another group C variant that possessed a non-functional β-TrcP binding motif due to two critical serine residues (S52 and S56) being substituted with isoleucine residues, showed reduced virus release activity but modest cytotoxic activity.

Conclusions

The natural variations exhibited by our Vpu variants involve extensive polymorphism characterized by substitution and deletions that contribute toward positive selection. We identified two major groups and an extremely rare β-TrcP binding motif mutant that show widely varying biological activities with potential implications for conferring subtype-specific pathogenesis.  相似文献   
430.
There are two developmentally regulated alternatively spliced forms of Disabled-1 (Dab1) in the chick retina: an early form (Dab1-E) expressed in retinal precursor cells and a late form (Dab1-L) expressed in neuronal cells. The main difference between these two isoforms is the absence of two Src family kinase (SFK) recognition sites in Dab1-E. Both forms retain two Abl/Crk/Nck recognition sites implicated in the recruitment of SH2 domain-containing signaling proteins. One of the Dab1-L-specific SFK recognition sites, at tyrosine(Y)-198, has been shown to be phosphorylated in Reelin-stimulated neurons. Here, we use Reelin-expressing primary retinal cultures to investigate the role of the four Dab1 tyrosine phosphorylation sites on overall tyrosine phosphorylation, Dab1 phosphorylation, SFK activation and neurite formation. We show that Y198 is essential but not sufficient for maximal Dab1 phosphorylation, SFK activation and neurite formation, with Y232 and Y220 playing particularly important roles in SFK activation and neuritogenesis, and Y185 having modifying effects secondary to Y232 and Y220. Our data support a role for all four Dab1 tyrosine phosphorylation sites in mediating the spectrum of activities associated with Reelin-Dab1 signaling in neurons.  相似文献   
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