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991.
Abbas Amin S. Mazloomzadeh A. Haniloo F. Mohammadian Asghar Fazaeli 《The Korean journal of parasitology》2012,50(4):371-374
Toxoplasma gondii is one of the major agents of infectious abortions and due to its worldwide distribution can threat healthy pregnant women who had no previous exposure to this parasite. The present study was designed to investigate the contribution of T. gondii to spontaneous abortions in Zanjan, Northwest of Iran, using ELISA method. Blood Samples were collected from 264 mothers referred to the provincial hospitals of Zanjan due to spontaneous abortion. The sera were isolated and subjected to evaluate the anti-Toxoplasma IgG, IgM and IgA antibodies. The results showed IgG positive (IgG+) in 99 cases (37.5%). A total of 68 women (25.8%) showed seroconversion with IgM or IgA or both IgM and IgA. They included: IgM+ in 21 (8.0%), IgA+ in 23 (8.7%) and both IgM+ and IgA+ in 24 (9.1%) subjects. In 23 cases, positive titers of IgM and IgG were accompanied. In general, the analysis of anti-Toxoplasma antibody patterns, showed that about 17% of the spontaneous abortions were associated with serological patterns of acute infection. According to these findings, a considerable proportion of spontaneous abortions can be attributed to T. gondii in the study area. 相似文献
992.
Anticoccidial activity of herbal complex in broiler chickens challenged with Eimeria tenella 总被引:1,自引:0,他引:1
The objective of the present study was to evaluate the anticoccidial effect of different concentrations of the herbal complex of 4 plants (leaves of Azadirachta indica and Nicotiana tabacum, flowers of Calotropis procera and seeds of Trachyspermum ammi) in broiler chickens in comparison with amprolium anticoccidial. Three concentrations (2 g, 4 g and 6 g) of herbal complex were given to the experimental groups once a day and amprolium (at the dose rate of 125 ppm) was given orally in drinking water from the 14th to the 21st days of age. One group was kept as infected, non-medicated control and one as non-infected, non-medicated control. All groups were inoculated orally with 75,000 sporulated oocysts on the 14th day of age except the non-infected, non-medicated control. Among herbal complex medicated groups, the maximum anticoccidial effect was seen in the group medicated with 6 g herbal complex followed by 4 g and 2 g herbal complex medicated groups. Treatment with 6 g of the herbal complex significantly reduced the negative performance and pathogenic effects associated with Eimeria tenella challenge at a level that was comparable with amprolium when using a largely susceptible recent field isolate. In summary, concentration-dependent anticoccidial activity of the studied herbal complex suggests its use as an alternative anticoccidial agent to chemotherapeutic drugs for Eimeria tenella control. 相似文献
993.
Analysis of ammonia-oxidizing bacteria dominating in lab-scale bioreactors with high ammonium bicarbonate loading 总被引:1,自引:0,他引:1
Vejmelkova D Sorokin DY Abbas B Kovaleva OL Kleerebezem R Kampschreur MJ Muyzer G van Loosdrecht MC 《Applied microbiology and biotechnology》2012,93(1):401-410
The ammonia-oxidizing bacterial community (AOB) was investigated in two types of laboratory-scale bioreactors performing partial
oxidation of ammonia to nitrite or nitrate at high (80 mM) to extremely high (428 mM) concentrations of ammonium bicarbonate.
At all conditions, the dominant AOB was affiliated to the Nitrosomonas europaea lineage as was determined by fluorescence in situ hybridization and polymerase chain reaction in combination with denaturing
gradient gel electrophoresis. Molecular analysis of the mixed populations, based on the 16S rRNA and cbbL genes, demonstrated the presence of two different phylotypes of Nitrosomonas, while microbiological analysis produced a single phylotype, represented by three different morphotypes. One of the most
striking features of the AOB populations encountered in the bioreactors was the domination of highly aggregated obligate microaerophilic
Nitrosomonas, with unusual cellular and colony morphology, commonly observed in nitrifying bioreactors but rarely investigated by cultural
methods. The latter is probably not an adaptation to stressful conditions created by high ammonia or nitrite concentrations,
but oxygen seems to be a stressful factor in these bioreactors. 相似文献
994.
Z Taslimi R Arezoomandan A Omranifard M Ghalandari-Shamami E Riahi AA Vafaei A Rashidy-Pour A Haghparast 《Peptides》2012,37(2):225-232
It has been shown that orexin A in the ventral tegmental area (VTA) is necessary for development of morphine place preference. Additionally, D1 and D2 dopamine receptors in the nucleus accumbens (NAc) have critical roles in motivation and reward. However, little is known about the function of orexin in conditioned place preference (CPP) in rats and involvement of D1/D2 receptors in the NAc. In the present study, we investigated the effect of direct administration of orexin A into the VTA, and examined the role of intra-accumbal dopamine receptors in development (acquisition) of reward-related behaviors in the rats. Adult male Wistar rats were unilaterally implanted by two separate cannulae into the VTA and NAc. The CPP paradigm was used, and, conditioning score and locomotor activity were recorded by Ethovision software. The results showed that unilateral intra-VTA administration of orexin A (27, 53 and 107ng/0.3μl saline) during conditioning phase induced CPP in a dose-dependent manner. The most effective dose of intra-VTA orexin-A in eliciting CPP was 107ng. However, intra-NAc administration of SCH 23390 (0.25, 1 and 4μg/0.5μl saline), a D1 receptor antagonist, and sulpiride (0.25, 1 and 4μg/0.5μl DMSO), a D2 receptor antagonist, inhibited the development of orexin-induced CPP. The inhibitory effect of D2 but not D1 receptor antagonist was exerted in a dose-dependent manner. It is supposed that the activation of VTA dopaminergic neuron by orexin impresses the D2 receptors more than D1 receptors in the NAc. 相似文献
995.
Falahati M Saboury AA Ma'mani L Shafiee A Rafieepour HA 《International journal of biological macromolecules》2012,50(4):1048-1054
Immobilization of enzymes into the mesoporous nanomaterials results in formation of more stable and even more active versions of biocatalysts. The effect of surface functionalization of mesoporous silica nanoparticles (MSNs) on its adsorption characteristics and stability of superoxide dismutase (SOD) was investigated. For this purpose, non-functionalized (KIT-6) and aminopropyl-functionalized cubic Ia3d mesoporous silica ([n-PrNH(2)-KIT-6]) nanoparticles with 3-dimensional pores were used as supports. It was observed that the amount of enzyme adsorbed on/within MSNs is dependent on the initial enzyme concentration for both KIT-6 and [n-PrNH(2)-KIT-6] mesoporous silicas. However a stronger interaction between SOD and [n-PrNH(2)-KIT-6] was observed relative to KIT-6. Increasing temperature favors a larger amount of SOD immobilization into KIT-6, while it was negligible for [n-PrNH(2)-KIT-6]. Immobilized SOD was more stable against urea and thermal denaturation relative to free enzyme and this improvement of stability was more pronounced for SOD into the [n-PrNH(2)-KIT-6] than KIT-6. These results may be useful in determining the mechanism(s) of protein immobilization and stabilization into the solid supports. 相似文献
996.
Narjes Okati Abbas Esmaili Sari Seyed Mahmood Ghasempouri 《Biological trace element research》2012,149(2):155-162
Coastal populations with high seafood consumption in the South Caspian Sea (Iran) have a significant exposure to dietary mercury. This study assesses the biomonitoring of mercury in mothers and breastfed infants in the South Caspian Sea. The mean of mercury concentration in the hair of 93 pairs of mothers and infants was obtained and was 3.55 and 1.89???g?g?1, respectively. A statistically significant correlation (R?=?0.850, P?=?0.000) was seen between mercury concentration in the hair of mothers and infants. The results of this study indicate that hair mercury concentrations exceeded the USEPA reference dose of 1???g?g?1 in 82.7?% of mothers and 61.2?% of infants. Also, 31?% of the mothers and 10.7?% of the infants had mercury concentrations more than the WHO ??threshold?? level (5???g?g?1). The age and fish consumption of mothers were the factors that significantly affected the hair mercury concentration of mothers and infants. Number of dental amalgam fillings of mothers was the factor that only affected mercury in the hair of mothers. According to the results, we can conclude that the main determinant of mercury exposure was the intake of mercury through fish consumption of mothers. 相似文献
997.
Response of Different Antibiotic Resistant Group of Streptococcus pyogenes to Environmental Stresses
Naser Abbas Mahmoud Ismail Mohamed El-Shahat Ebeid 《Indian journal of microbiology》2012,52(3):354-359
Streptococcus species is considered as an important pathogen for human and animals. The antibiotic resistance mechanism in this species is continuously increased. On the other side, the tolerance of environmental stresses play an effective role in the severity of many streptococcal causative disease. In this study we assayed survey on the causative agents of pharyngitis and tonsillitis patients. The predominant causative strain was Streptococcus pyogenes with 93 % isolating ratio frequency. The other pathogenic species were S. agalactia 5.3 % and S. pneumonia 1.7 %. According to the antibiotic resistant test the S. pyogenes isolates were classified into six different groups. A selected strain from each antibiotic resistant group was tested for tolerance of a restrictive environmental factors. The variations of the environmental niches of isolates were in consistence with their antibiotic resistant variation. 相似文献
998.
Moravej A Rasouli M Kalani M Asaei S Kiany S Najafipour S Koohpayeh A Abdollahi A 《Molecular biology reports》2012,39(6):6907-6914
Lymphotoxin-α (LT-α) and interleukin-1beta (IL-1β) are proinflammatory cytokines playing important roles in immunity against
Leishmania infection and the outcome of the disease. As cytokine productions are under the genetic control, this study tried to find
any probable relationship between these cytokine gene polymorphisms and the susceptibility to visceral leishmaniasis in Iranian
pediatric patients. Ninety-five pediatric patients involved with visceral leishmaniasis and 128 non-relative healthy people,
from the same area as the patients, were genotyped for LT-α (+252A/G) and IL-1β (+3953T/C and −511T/C) gene polymorphisms
using polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP). There was not found any significant differences
in allele and genotype frequencies of LT-α (+252A/G) and IL-1β (+3953) among the study groups. However, the frequency of IL-1β
−511TT genotype was higher in the controls (P = 0.0004) while the frequency of IL-1β −511CC genotype and C allele were higher in the patients (P = 0.008 and P = 0.00006, respectively). Furthermore, IL-1β CC (−511/+3953) haplotype was more frequent in VL patients compared with the
controls (P = 0.0002) and the distribution of TT haplotype was higher in the controls compared with the patients (P = 0.003). In conclusion, based on the results, IL-1β −511C allele, CC genotype and CC (−511/+3953) haplotype could be considered
as the susceptibility factors for visceral leishmaniasis while IL-1β −511TT genotype, T allele and TT haplotype (−511/+3953)
might be counted as the influential factors for resistance to the disease. 相似文献
999.
Sadati N Jenett-Siems K Siems K Ardekani MR Hadjiakhoondi A Akbarzadeh T Ostad SN Khanavi M 《Zeitschrift für Naturforschung. C, Journal of biosciences》2012,67(5-6):275-281
The n-butanolic fraction of a methanolic extract (80%) from aerial parts of Ajuga chamaecistus ssp. tomentella was analysed using different chromatographic methods. Column (CC) and high-performance liquid chromatography (HPLC) were used for isolation and purification. 13C, H NMR, H-H COSY, HSQC, HMBC, and ESI-MS were employed for identification of the compounds isolated from this fraction. The structures of the compounds were determined to be cis-melilotoside (1), trans-melilotoside (2), lavandulifolioside (3), 20-hydroxyecdysone (4), leonoside B (5), martynoside (6), ajugalactone (7), makisterone A (8), and 24-dehydroprecyasterone (9). This is the first report on the presence of cis- and trans-melilotoside in Ajuga species. Cytotoxic evaluation of the n-butanolic fraction, cis- and trans-melilotoside against cancer (T47D, HT-29, and Caco-2) and normal (NIH 3T3) cell lines by the mitochondrial tetrazolium test (MTT) showed no cytotoxic effects up to 400 microg/mL. The results of this study suggest that melilotoside, phenylethyl glycosides, and phytoecdysteroids are the main constituents of the n-butanolic fraction of Ajuga chamaecistus ssp. tomentella. 相似文献
1000.
Khansa S Hoteit R Shammaa D Khalek RA El Halas H Greige L Abbas F Mahfouz RA 《Gene》2012,506(2):396-399