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1.
Curacron is an organophosphorus pesticide widely used in cotton fields. In order to assay its mutagenic potential in mammalian germ cells chromosomal aberrations in spermatogonial cells and sperm abnormalities were examined in mice after Curacron treatment. For studying chromosomal aberrations mice were treated both acutely (single treatment) and subacutely (for 5 consecutive days) with 3 dose levels of Curacron, 12, 36 and 72 mg/kg. Curacron was found to produce a significant increase in structural chromosomal aberrations after acute and subacute treatments. This increase was dose-dependent. A dose-dependent inhibition in mitotic activity in spermatogonia was also found. For studying sperm abnormalities mice were treated for 5 consecutive days with 20, 40 and 60 mg/kg. Morphological sperm abnormalities increased significantly after treatment with Curacron. The increase was dose-dependent. An inhibition of 40.2% in sperm count and of 74.5% in sperm motility occurred after treatment with 60 mg/kg Curacron. These results show that Curacron has a damaging effect on spermatogonial cells as well as on sperm morphology.  相似文献   
2.
Five locally isolated bacterial strains produced extracellular cellulase enzymes, primarily CMCase, when grown on different natural and commercial cellulosic substrates. Extracellular CMCase and avicelase activity was higher with the strain CLS-32, a Cytophaga sp., compared to four other strains. The whole-cell preparations of these isolates were found to saccharify cellulosic substrates to reducing sugars. Maximum release of reducing sugar (5.75 mg ml−1) was obtained with CLS-32 using sugar cane bagasse as growth and hydrolysis substrates.  相似文献   
3.
Buffalo semen was diluted (1:2) with lactose diluent containing caffeine (2, 4 and 6 mM). Diluted semen samples were frozen in a pellet form (0.15 ml), thawed 24 h after freezing in 2.9% sodium citrate for 30 sec and incubated at 37 degrees C for 3 h. Addition of caffeine to diluted buffalo semen before freezing resulted in a significant increase in the post-thaw motility of spermatozoa over the 3-h incubation period. When caffeine was added to the thawing medium, the post-thaw motility was further improved. Thus, the increase in motility due to caffiene treatment was even more pronounced than in samples treated with caffiene before freezing.  相似文献   
4.
5.

Background

Ad35.CS.01 is a pre-erythrocytic malaria candidate vaccine. It is a codon optimized nucleotide sequence representing the P. falciparum circumsporozoite (CS) surface antigen inserted in a replication deficient Adenovirus 35 backbone. A Phase 1a trial has been conducted in the USA in naïve adults and showed that the vaccine was safe. The aim of this study is to assess the safety and immunogenicity of ascending dosages in sub Saharan Africa.

Methods

A double blind, randomized, controlled, dose escalation, phase Ib trial was conducted in a rural area of Balonghin, the Saponé health district (Burkina Faso). Forty-eight healthy adults aged 18-45 years were randomized into 4 cohorts of 12 to receive three vaccine doses (day 0, 28 and 84) of 109, 1010, 5X1010, 1011 vp of Ad35.CS.01 or normal saline by intra muscular injection. Subjects were monitored carefully during the 14 days following each vaccination for non serious adverse events. Severe and serious adverse events were collected throughout the participant study duration (12 months from the first vaccination). Humoral and cellular immune responses were measured on study days 0, 28, 56, 84, 112 and 140.

Results

Of the forty-eight subjects enrolled, forty-four (91.7%) received all three scheduled vaccine doses. Local reactions, all of mild severity, occurred in thirteen (27.1%) subjects. Severe (grade 3) laboratory abnormalities occurred in five (10.4%) subjects. One serious adverse event was reported and attributed to infection judged unrelated to vaccine. The vaccine induced both antibody titers and CD8 T cells producing IFNγ and TNFα with specificity to CS while eliciting modest neutralizing antibody responses against Ad35.

Conclusion

Study vaccine Ad35.CS.01 at four different dose levels was well-tolerated and modestly immunogenic in this population. These results suggest that Ad35.CS.01 should be further investigated for preliminary efficacy in human challenge models and as part of heterologous prime-boost vaccination strategies.

Trial Registration

ClinicalTrials.gov NCT01018459 http://clinicaltrials.gov/ct2/show/NCT01018459  相似文献   
6.

MicroRNAs (miRNAs) play important roles in liver pathologies and they are potential biomarkers for diagnosis of liver diseases progression. Changes in miRNA sera expression can be used as non-invasive biomarkers for hepatocellular carcinoma (HCC). The aim of the study was to identify the miRNome profiling of HCC and its diagnostic value in distinguishing HCC from healthy individuals. Expression profiles of miRNAs in serum samples of 20 HCC patients and 10 healthy controls were detected. Whole miRNome profiling was done using next generation sequencing. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of the deregulated miRNAs for discriminating HCC cases from healthy controls. MiRNA 142 was highly expressed in HCC (P value?=?0.023) while miRNAs 191, 22, and 126 were higher in the controls (P value?=?0.005, 0.034, 0.010 respectively). We have identified 5 novel miRNAs and they were highly expressed in HCC than controls. Analysis of ROC curve demonstrated that these deregulated miRNAs can be used as a reliable biomarker for detection of HCC with high diagnostic accuracy (AUC?=?0.93). We have detected a panel of serum miRNAs that can be used as a reliable noninvasive screening biomarker of HCC. The study recommends further research to shed light on a possible role of the newly discovered novel miRNAs in HCC pathogenesis.

  相似文献   
7.
This work was based on field screening procedure to detect the population density of Aphis craccivora for two successive seasons (2004–2005) and (2005–2006) to emphasis the relation between the economic injury level (EIL) and yield loss.

Results obtained showed that the equilibrium position (steady point) during the first and second season was 9.06 and 3.32 individuals/five leaflets, respectively, while the injury level was 3.4 and 1.16 individuals/leaflets. When the bean plant was subjected to three successive insecticidal applications during the early growing, season is sufficient to decrease the yield loss significantly (yield capacity 21.43 Ard./fed.) with comparing to untreated plant (14.98 Ard./fed.), while the plants exposure for one treatment was 17.36 Ard./fed. The EIL was 8.6 individual of aphids/plant depending on the market price of bean and control cost during the season.  相似文献   
8.
To develop conducting organic polymers (COPs) as luminescent sensors for determination of toxic heavy metals, a new benzene sulfonic acid‐doped polypyrrole (PPy‐BSA) thin film was electrochemically prepared by cyclic voltammetry (CV) on flexible indium tin oxide (ITO) electrode in aqueous solution. PPy‐BSA film was characterized by FTIR spectrometry, X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The optical properties of PPy‐BSA were investigated by ultraviolet (UV)‐visible absorption and fluorescence spectrometry in dimethylsulfoxide (DMSO) diluted solutions. PPy‐BSA fluorescence spectra were strongly quenched upon increasing copper(II) ion (Cu2+) and lead(II) ion (Pb2+) concentrations in aqueous medium, and linear Stern–Volmer relationships were obtained, which indicated the existence of a main dynamic fluorescence quenching mechanism. BSA‐PPy sensor showed a high sensitivity for detection of both metallic ions, Cu2+ and Pb2+, with very low limit of detection values of 3.1 and 18.0 nM, respectively. The proposed quenching‐fluorimetric sensor might be applied to the determination of traces of toxic heavy metallic ions in water samples.  相似文献   
9.
Biological Trace Element Research - The efficacy of Moringa oleifera leaf extract (MO) in alleviating nephrotoxicity induced by titanium dioxide nanoparticles (TiO2 NPs) was studied. Rats were...  相似文献   
10.
The present study aimed to isolate, select, and evaluate bacterial isolates with potential for use as biological indicators for sterilization with glutaraldehyde and/or formaldehyde. A total of 340 local Bacillus isolates were screened for glutaraldehyde and/or formaldehyde resistance by determination of minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs), and extinction time and were compared with B. subtilis (var. niger) ATCC 9372, the biological indicator for ethylene oxide sterilization, as reference. Of these, 85 isolates had glutaraldehyde MICs of 0.5% or higher, while 29 had formaldehyde MICs of 0.04% or higher. Of the 29 resistant isolates, 15 had MBCs of 0.05% or more. Extinction times were used to evaluate the bactericidal/sporicidal activity of glutaraldehyde. Eight had inactivation times of more than 5 h in 2% glutaraldehyde (pH 8), whereas 12 had inactivation times of more than 3 h in l% formaldehyde, with one isolate in common. These 19 isolates were selected and evaluated as potential biological indicators for aldehydes by determination of the decimal reduction times (D values), compared with the reference strain. Eight glutaraldehyde-resistant isolates exhibited D values 2.0- to 3.5-fold higher than the reference strain (30 min.). Only five of 12 formaldehyde resistant isolates had D values higher than that of the reference strain. Using six resistant isolates, temperature coefficient values between 2.11 and 3.02 were obtained for 2% formaldehyde. Finally, 14 isolates were tested for potential pathogenicity and were identified to species level. All of the eight glutaraldehyde-resistant isolates, including the isolate with dual resistance, and three formaldehyde-resistant isolates were B. licheniformis, while two other formaldehyde-resistant isolates were B. cereus. Six of the selected B. licheniformis isolates are potential biological indicators for sterilization processes using aldehydes. Three can be suggested for glutaraldehyde only and three for both aldehydes. Electronic Publication  相似文献   
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