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111.
Acute kidney injury (AKI) is a well-known complication of cisplatin-based chemotherapy; however, its impact on long-term patient survival is unclear. We sought to determine the incidence and risk factors for development of cisplatin-associated AKI and its impact on long-term renal function and patient survival. We identified 233 patients who received 629 cycles of high-dose cisplatin (99±9mg/m2) for treatment of head and neck cancer between 2005 and 2011. These subjects were reviewed for development of AKI. Cisplatin nephrotoxicity (CN) was defined as persistent rise in serum creatinine, with a concomitant decline in serum magnesium and potassium, in absence of use of nephrotoxic agents and not reversed with hydration. All patients were hydrated per protocol and none had baseline glomerular filtration rate (GFR) via CKD-EPI<60mL/min/1.73m2. The patients were grouped based on development of AKI and were staged for levels of injury, per KDIGO-AKI definition. Renal function was assessed via serum creatinine and estimated glomerular filtration rate (eGFR) via CKD-EPI at baseline, 6- and 12-months. Patients with AKI were screened for the absence of nephrotoxic medication use and a temporal decline in serum potassium and magnesium levels. Logistic regression models were constructed to determine risk factors for cisplatin-associated AKI. Twelve-month renal function was compared among groups using ANOVA. Kaplan-Maier curves and Cox proportional hazard models were constructed to study its impact on patient survival. Of 233 patients, 158(68%) developed AKI; 77 (49%) developed stage I, 55 (35%) developed stage II, and 26 (16%) developed stage III AKI. Their serum potassium and magnesium levels correlated negatively with level of injury (p<0.05). African American race was a significant risk factor for cisplatin-associated AKI, OR 2.8 (95% CI 1.3 to 6.3) and 2.8 (95% CI 1.2 to 6.7) patients with stage III AKI had the lowest eGFR value at 12 months (p = 0.05) and long-term patient survival (HR 2.1; p<0.01) than patients with no or lower grades of AKI. Most common causes of death were recurrent cancer (44%) or secondary malignancy elsewhere (40%). Cisplatin-associated severe AKI occurs in 20% of the patients and has a negative impact on long-term renal function and patient survival. PEG tube placement may be protective and should be considered in high risk-patients.  相似文献   
112.
The interaction of etravirine with β-cyclodextrin is analyzed by UV–visible absorption, infrared, fluorescence, nuclear magnetic resonance, two-dimensional rotational frame nuclear Overhauser effect spectroscopy, and molecular modeling studies. The 4-hydroxy-3, 5-dimethylbenzonitrile moiety is found to take part in the binding. The stoichiometry of the inclusion complex of ET with β-CD is 1:1 with the binding constant of 2.03 × 103 mol?1 dm3. The binding of ET with calf thymus DNA (ctDNA) and bovine serum albumin (BSA) protein is investigated in the presence and the absence of β-CD. Fluorescence enhancement is observed during the binding of ET with ctDNA in the absence of β-CD, whereas in the presence of β-CD, fluorescence quenching is observed. The binding constants of the binding of ET and ET–β-CD to ctDNA are 7.84 × 104 and 4.38 × 104 mol?1 dm3, respectively. The binding constant of the binding of ET and ET–β-CD to BSA are 3.14 × 104 and 1.6396 × 104 mol?1 dm3, respectively. The apparent binding constants between ET–β-CD complex and ctDNA or BSA protein decreases significantly. The numbers of binding sites of interaction of ET with BSA protein and the binding distance between BSA protein and ET the absence and the presence of β-CD differ. β-CD modulates the binding of ET with the macromolecular targets.  相似文献   
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114.

Background

Humans frequently engage in arbitrary, conventional behavior whose primary purpose is to identify with cultural in-groups. The propensity for doing so is established early in human ontogeny as children become progressively enmeshed in their own cultural milieu. This is exemplified by their habitual replication of causally redundant actions shown to them by adults. Yet children seemingly ignore such actions shown to them by peers. How then does culture get transmitted intra-generationally? Here we suggest the answer might be ‘in play’.

Principal Findings

Using a diffusion chain design preschoolers first watched an adult retrieve a toy from a novel apparatus using a series of actions, some of which were obviously redundant. These children could then show another child how to open the apparatus, who in turn could show a third child. When the adult modeled the actions in a playful manner they were retained down to the third child at higher rates than when the adult seeded them in a functionally oriented way.

Conclusions

Our results draw attention to the possibility that play might serve a critical function in the transmission of human culture by providing a mechanism for arbitrary ideas to spread between children.  相似文献   
115.
In the present study, nsSNPs in EPHX1, GSTT1, GSTM1 and GSTP1 genes were screened for their functional impact on concerned proteins and their plausible role in breast cancer susceptibility. Initially, SNPs were retrieved from dbSNP, followed by identification of potentially deleterious nsSNPs using PolyPhen and SIFT. Functional analysis was done with SNPs3D, SNPs&GO and MutPred methods. Prediction and evaluation of the functional impact on the 3D structure of proteins were performed with Swiss PDB viewer and NOMAD-Ref servers. On analysis, 13 nsSNPs were found to be highly deleterious and damaging to the protein structure, of which 6 nsSNPs, rs45549733, rs45506591 and rs4986949 of GSTP1, rs72549341 and rs148240980 of EPHX1 and rs17856199 of GSTT1 were predicted to be potentially polymorphic. It is therefore hypothesized that the 6 identified nsSNPs may alter the detoxification process and elevate carcinogenic metabolite accumulation thus modifies the risk of breast cancer susceptibility in a group of women.  相似文献   
116.
Sequestration of CO2 by autotrophic bacteria is a key process of biogeochemical carbon cycling in soil ecosystem. Rhizosphere is a rich niche of microbial activity and diversity, influenced by change in atmospheric CO2. Structural changes in rhizosphere composition influence microbial communities and the nutrient cycling. In the present study, the bacterial diversity and population dynamics were established using cbbL and 16S rRNA gene targeted metagenomics approach from the rhizosphere of Arachis hypogaea. A total of 108 cbbL clones were obtained from the rhizospheric soil which revealed predominance of cbbL sequences affiliated to Rhizobium leguminosarum, Bradyrhizobium sp., Sinorhizobium meliloti, Ochrobactrum anthropi and a variety of uncultured cbbL harboring bacteria. The 16S rRNA gene clone library exhibited the dominance of Firmicutes (34.4%), Proteobacteria (18.3%), Actinobacteria (17.2%) and Bacteroidetes (16.1%). About 43% nucleotide sequences of 16S rRNA gene clone library were novel genera which showed < 95% homology with published sequences. Gene copy number of cbbL and 16S rRNA genes, determined by quantitative real‐time PCR (qRT PCR), was 9.38 ± 0.75 × 107 and 5.43 ± 0.79 × 108 (per g dry soil), respectively. The results exhibited bacterial community structure with high bacterial diversity and abundance of CO2‐fixing bacteria, which can be explored further for their role in carbon cycling, sustainable agriculture and environment management.  相似文献   
117.
Water quality greatly influences the population density of aquatic biota, including parasites. In order to evaluate the relationship between fish parasites and water quality in Kashmir Himalayas, we assessed helminth parasite densities in Schizothorax niger Heckel, 1838 (an endemic cyprinid fish of Kashmir) from three lakes, namely Anchar, Manasbal and Dal, which reflected the varied stages of eutrophication. The overall prevalence of helminth infections was higher in the hypertrophic Anchar Lake (prevalence = 18.6%) compared to Manasbal Lake, which was the least eutrophied (prevalence = 6.4%). Furthermore, mean prevalence of monoxenous and heteroxenous parasites was higher in lakes containing higher levels of water degradation (Anchar and Dal). The mean number of helminth species per fish host was the highest in the hypertrophic lake (1.3 ± 0.3) in comparison to the least eutrophic lake (0.2 ± 1.5). Variability of calculated infection indices (prevalence, mean intensity and mean abundance) revealed that helminth parasite composition in the fish was affected by the lakes' environmental stress (degraded water quality). Therefore, data on the density of helminth parasites in fish can provide supplementary information on the pollution status of a water body.  相似文献   
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119.
Cedrus deodara (deodar) is practically used, as insect repellent, in the northern areas of Pakistan but no data available therefore this study was conducted to evaluate the effectiveness of deodar oil as an alternate of conventional insecticides against the larval pest stage of mealworm beetle (Tenebrio molitor), by feeding method. The aim of the study was to investigate the effectiveness of deodar oil as an alternate of conventional insecticides against the larval pest stage of mealworm beetle (Tenebrio molitor), by feeding method. All tested chemicals showed efficacy against the pests. The LC50 was determined by probit analysis and was found to be 3.41, 0.086 and 0.023% of larvae treated with deodar oil, Carbosulfan and Imidacloprid respectively The LC50 treated larvae were subjected to the evaluation of protein activity, qualitatively and quantitatively. The protein level in tested insects was enhanced when treated with Imidacloprid, Carbosulfan and deodar oil. The electrophoretic profile of treated insects showed more bands in insects treated with Cedrus deodara oil. This electrophoretic profile appeared in 4, 5, 7 and 8 bands for tested chemicals including control. Antifeedant activity was observed for C. deodara as larvae were deterred to feed on the food found in the container.  相似文献   
120.
Nematodes are the most diverse and highly significant group of soil-inhabiting microorganisms that play a vital role in organic material decomposition and nutrient recycling.Diverse geographical locations and environmental gradients show a significant impact on the diversity of nematodes. Present study aims to assess the effects of ecological (altitude, temperature, moisture) and edaphic (soil pH, nutrients, soil patches) factors on the soil nematode diversity and structure at five different landscape patches (forests, apple orchards, rice fields, pastures, and alpine zone) from ten different sites of Kashmir valley (India). Differences in the altitudinal gradients results in the shift of generic nematode population. Among the soil patches, highest nematode diversity was observed in forest soil and least in alpine soil; however, bacteriovorous nematodes dominated all the soil patches. The temperature and moisture have a significant effect on nematode diversity, the highest nematode trophic levels were observed above 21°C temperature, and 30% moisture. Nematode abundance decreased from alkaline to acidic pH of the soil. Soil nutrients such as, nitrogen (N) and phosphorus (P) have shown a detrimental effect in nematode richness at each site, where nematode diversity and richness of genera were higher at abundant soil N and P but decreased at low soil nutrients. Ecological indices like diversity index (DI), Shannon-Wiener Index (H'), enrichment index (EI), and maturity Index (MI) values demonstrated forest soil more favourable for nematodes and high soil health status than other soil patches. This study suggested that these indices may be helpful as soil monitoring tools and assessing ecosystem sustainability and biodiversity.  相似文献   
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