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1.

Background

BC RNAs and the fragile X mental retardation protein (FMRP) are translational repressors that have been implicated in the control of local protein synthesis at the synapse. Work with BC1 and Fmr1 animal models has revealed that phenotypical consequences resulting from the absence of either BC1 RNA or FMRP are remarkably similar. To establish functional interactions between BC1 RNA and FMRP is important for our understanding of how local protein synthesis regulates neuronal excitability.

Methodology/Principal Findings

We generated BC1−/− Fmr1−/− double knockout (dKO) mice. We examined such animals, lacking both BC1 RNA and FMRP, in comparison with single knockout (sKO) animals lacking either one repressor. Analysis of neural phenotypical output revealed that at least three attributes of brain functionality are subject to control by both BC1 RNA and FMRP: neuronal network excitability, epileptogenesis, and place learning. The severity of CA3 pyramidal cell hyperexcitability was significantly higher in BC1−/− Fmr1−/− dKO preparations than in the respective sKO preparations, as was seizure susceptibility of BC1−/− Fmr1−/− dKO animals in response to auditory stimulation. In place learning, BC1−/− Fmr1−/− dKO animals were severely impaired, in contrast to BC1−/− or Fmr1−/− sKO animals which exhibited only mild deficits.

Conclusions/Significance

Our data indicate that BC1 RNA and FMRP operate in sequential-independent fashion. They suggest that the molecular interplay between two translational repressors directly impacts brain functionality.  相似文献   
2.
There has been considerable progress over the last decade in development of the perovskite solar cells (PSCs), with reported performances now surpassing 25.2% power conversion efficiency. Both long‐term stability and component costs of PSCs remain to be addressed by the research community, using hole transporting materials (HTMs) such as 2,2′,7,7′‐tetrakis(N,N′‐di‐pmethoxyphenylamino)‐9,9′‐spirbiuorene(Spiro‐OMeTAD) and poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] (PTAA). HTMs are essential for high‐performance PSC devices. Although effective, these materials require a relatively high degree of doping with additives to improve charge mobility and interlayer/substrate compatibility, introducing doping‐induced stability issues with these HTMs, and further, additional costs and experimental complexity associated with using these doped materials. This article reviews dopant‐free organic HTMs for PSCs, outlining reports of structures with promising properties toward achieving low‐cost, effective, and scalable materials for devices with long‐term stability. It summarizes recent literature reports on non‐doped, alternative, and more stable HTMs used in PSCs as essential components for high‐efficiency cells, categorizing HTMs as reported for different PSC architectures in addition to use of dopant‐free small molecular and polymeric HTMs. Finally, an outlook and critical assessment of dopant‐free organic HTMs toward commercial application and insight into the development of stable PSC devices is provided.  相似文献   
3.
Twelve fungi namelyAlternaria alternata, Aspergillus flavus, A niger, A ochraceus, Actinomucor repens, Capnodoium spp., Curvularia lunata, Fusarium pallidoroseum, F solani, F verticillioides, Penicillium citrinum and Rhizopus stolonifer were recorded from samples ofAegle marmelos, Aesculus indica, Buchanania lanzan andPinus gerardiana. In case ofPrunus amygdalus only Rstolonifer was recorded. A significant variation in pattern of mycoflora incidence was observed in terms of source and season. Fungal infestation in most of the substrates was found to be highest during monsoon. Aflatoxins were the most common mycotoxins elaborated by different isolates ofA flavus obtained fromA marmelos, B lanzan andP gerardiana. The amount of aflatoxins produced by the toxigenic isolates ofA flavus was in the range of traces to 0.9–26.0 μg/ml inA marmelos, 0.8–17.5 μg/ml inP gerardiana and 0.65–13.2 μg/ml inB lanzan. The percentage toxigenicity was comparatively lower in the isolates of other mycotoxigenic fungi. Aflatoxins were detected almost in all the samples analyzed for mycotoxin contamination. However, traces of zearalenone were detected inA marmelos. The concentration of aflatoxin B1 was in the range of 0.13–0.75 μg/g inA marmelos, 0.09–0.60 μg/g inP gerardiana and 0.01–0.20 ug/g inB lanzan. Mycotoxins were not detected inAesculus indica andPrunus amygdalus.  相似文献   
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Summary A field experiment was conducted on a calcareous vertisol at Mahatma Phule Agricultural University, Rahuri to study the release of Fe, Mn and P in soil and yield of two rice cultivars due to different soil water treatments for 15 days prior to sowing. Soil saturation (daily two irrigations) for 15 days prior to sowing increased the supply of Fe, Mn and P in soil at sowing as a result of reduction in pH and Eh. Dry matter yield at different growth stages as well as grain yields of Karjat 184 (dwarf) and Tuljapur 1 (tall) also increased due to presowing soil saturation treatment. Tuljapur 1 yielded more than Karjat 184 when grown under upland conditions. Laboratory incubation studies showed reduction in soil pH (from 8.6 to 7.5) and Eh (from +501 to +362 mv) at the end of 15 days under soil submergence treatment. Availability of Fe, Mn and P was also found to be increased.  相似文献   
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OBJECTIVE: To study the role of fine needle aspiration cytology (FNAC) and ancillary studies in the diagnosis of tubercular epididymitis or epididymo-orchitis. STUDY DESIGN: Forty patients with tubercular epididymitis or epididymoorchitis diagnosed on FNAC underwent a detailed clinical workup, imaging and microbiologic studies before being started on antitubercular treatment (ATT). One patient underwent orchiectomy. RESULTS: Clinically, the disease presented in patients of all ages usually as a scrotal swelling or rarely as a scrotal sinus (3) or abscess (3) or as part of disseminated tuberculosis (2). Three patients gave a history of previous tuberculosis. Scrotal sonography confirmed the involvement of the epididymis, testis or spermatic cord in each case. FNAC was diagnostic in 27 aspirates (epithelioid cell granulomas with caseation) but nondiagnostic in the rest. Tubercular etiology was confirmed directly by detection of acid-fast bacilli (AFB) on FNA smears in 24 (60%) patients and urine samples in 11 and indirectly in 9 patients with negative AFB by using a combination of a positive Mantoux test (5 of 9), presence of caseating granulomas on FNA smears (7 of 9) and therapeutic response to ATT (9 of 9). CONCLUSION: FNA as a minimally invasive technique plays a prime role in the diagnosis of tubercular epididymitis and epididymoorchitis. It provides adequate material for cytologic and microbiologic examination and helps to avoid unnecesary orchiectomy.  相似文献   
8.
A series of hydrazone and 3-nitrovinyl analogs of indole-3-carboxaldehydes and related compounds were synthesized and screened for antitubercular activity against Mycobacterium tuberculosis H37R(V) in BACTEC 12B medium using the Microplate Alamar Blue Assay (MABA). Several compounds showed inhibitory activity against M. tuberculosis in primary screening assays at a concentration of 6.25 microg/mL; subsequent dose-response studies indicated that the most active compounds, 3d, 3e & 8b, had IC(50) values of 5.96, 5.4 & 1.6 microg/mL, respectively. These compounds represent potential leads for the further development of novel antitubercular agents.  相似文献   
9.

Background

Estimates of the effectiveness of influenza vaccines in older adults may be biased because of difficulties identifying and adjusting for confounders of the vaccine-outcome association. We estimated vaccine effectiveness for prevention of serious influenza complications among older persons by using methods to account for underlying differences in risk for these complications.

Methods

We conducted a retrospective cohort study among Ontario residents aged ≥65 years from September 1993 through September 2008. We linked weekly vaccination, hospitalization, and death records for 1.4 million community-dwelling persons aged ≥65 years. Vaccine effectiveness was estimated by comparing ratios of outcome rates during weeks of high versus low influenza activity (defined by viral surveillance data) among vaccinated and unvaccinated subjects by using log-linear regression models that accounted for temperature and time trends with natural spline functions. Effectiveness was estimated for three influenza-associated outcomes: all-cause deaths, deaths occurring within 30 days of pneumonia/influenza hospitalizations, and pneumonia/influenza hospitalizations.

Results

During weeks when 5% of respiratory specimens tested positive for influenza A, vaccine effectiveness among persons aged ≥65 years was 22% (95% confidence interval [CI], −6%–42%) for all influenza-associated deaths, 25% (95% CI, 13%–37%) for deaths occurring within 30 days after an influenza-associated pneumonia/influenza hospitalization, and 19% (95% CI, 4%–31%) for influenza-associated pneumonia/influenza hospitalizations. Because small proportions of deaths, deaths after pneumonia/influenza hospitalizations, and pneumonia/influenza hospitalizations were associated with influenza virus circulation, we estimated that vaccination prevented 1.6%, 4.8%, and 4.1% of these outcomes, respectively.

Conclusions

By using confounding-reducing techniques with 15 years of provincial-level data including vaccination and health outcomes, we estimated that influenza vaccination prevented ∼4% of influenza-associated hospitalizations and deaths occurring after hospitalizations among older adults in Ontario.  相似文献   
10.
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