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91.
In this study, different immersion times were compared for optimization of Chlorophytum borivilianum microtuber production in a RITA (Récipient à Immersion Temporaire Automatique) system. Significantly higher mean number and length of microtubers and growth index were obtained (16, 52 mm and 16, respectively) with 15 min immersion in microtuberization medium (MM) for every 60 min rest period, and could eliminate the occurrence of hyperhydricity. The substitution of MM with liquid hormone-free MS (MSO) medium on week 6 of culture differed significantly in terms of mean number and length of microtubers and growth index compared to earlier substitution at week 3 with MSO but did not differ significantly in comparison to cultures maintained throughout the 9 weeks in MM. Comparison of total saponin of TIS-derived microtubers with tubers of field grown mother plant showed a 1.3-fold increase of saponin (≈21% diosgenin) in the microtubers. The above results hold a promising application of TIS for large scale production of microtubers and accumulated saponin in C. borivilianum.  相似文献   
92.
The levels of liver lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamins A and E were used to follow the level of oxidative damage caused by ionizing radiation in pregnant rats. The possible protective effects of selenium and vitamin E supplemented to rats housed in concrete-protected cages using hematite and colemanite were tested and compared to untreated controls. Ninety-six rats were randomly divided into four main equal groups namely control (A), normal concrete (B), concrete containing colemanite (C), and concrete containing hematite (D). Except group A, all groups exposed to 7 Gy radiation. The four main groups were divided into four subgroups each as follows: subgroups 1 (n?=?6): nonpregnant control rats. Subgroups 2 (n?=?6): selenium and vitamin E combination was intraperitoneally (i.p.) given to the nonpregnant rats for 20 days. Subgroups 3 (n?=?6): pregnant control rats. Subgroups 4 (n?=?6): selenium and vitamin E combination was i.p. given to the pregnant rats for concessive 20 days. Lactate dehydrogenate, alkaline phosphates, and lipid peroxidation values were higher in subgroups 1 and 3 than in no radiation group although glutathione peroxidase and vitamin E levels in liver were lower in radiation group than in no radiation group. Lactate dehydrogenate activity and lipid peroxidation levels were found to be decreased in subgroups 2 and 4 protected with concrete containing hematite and colemanite when compared to subgroup 1 and 3 with normal concrete. The radiation doses in rats housed by concrete without colemanite and hematite exposed radiation clearly showed liver degeneration. In conclusion, selenium and vitamin E supplementations and housing by concrete with colemanite was found to offer protection against gamma-irradiation-induced liver damage and oxidative stress in rats, probably by exerting a protective effect against liver necrosis via its free radical scavenging and membrane stabilizing. Protective effects of colemanite in the liver seem to be more important than in hematite.  相似文献   
93.
This study was carried out on nine 3–5-year-old rams of different species: four Norduz, two Karakas, and three Ile de France?×?Akkaraman rams. Sperm of each ram was collected by means of an artificial vagina once per month from June to October 2007. In each case, the sperm volume, pH, viscosity, mass activity, motility, concentration, abnormal spermatozoa ratio, and the sperm death/live ratio were recorder along with the animals’ testis diameter and scrotum circumferences. The concentrations of calcium, potassium, copper, magnesium, iron, and zinc levels in seminal plasma were determined. There were changes in the measured parameters according to genotype and time of sampling, which can be useful for better planning of anestrous mating programs for these ram species.  相似文献   
94.
Bacterial ferritin contains 24 haem groups   总被引:4,自引:0,他引:4  
F H Kadir  G R Moore 《FEBS letters》1990,271(1-2):141-143
Pseudomonas aeruginosa bacterioferritin, also known as cytochrome b1 or cytochrome b557, has been isolated with 9 haems per 24 subunits. Various forms of the protein have been prepared including the completely haem-free protein and the fully haem-loaded protein with 24 haems per 24 subunits. The presence of the core does not significantly affect haem addition or removal. The absorbance ratio of the non-haem-iron-loaded protein, 278 nm:417 nm (oxidised), can be used to estimate the haem loading.  相似文献   
95.
96.
The present study was conducted to evaluate the serum selenium levels in first-degree relatives of diabetic patients (FDR) according to controls. Insulin resistance, serum lipid levels, inflammation markers, and blood pressure were also studied in these patients. Serum levels of selenium in FDR were significantly lower than control group (74.65 ± 5.9 vs 88.7 ± 8.7 μg/dl, p < 0.0001). HsCRP, HOMA-IR, insulin, homocysteine levels were significantly higher in FDR according to the control group (1.32 ± 0.9 vs 0.63 ± 0.4 mg/dL, p < 0.0001; 2.07 ± 0.84 vs 1.51 ± 0.69, p < 0.0001; 9.26 ± 3.8 vs 6.8 ± 2.98 μU/MI, p < 0.0001; 15.7 ± 7.4 vs 11.5 ± 5.1 μmol/L, p < 0.0001, respectively). There was significant correlation between selenium levels and hsCRP (r = − 0.450, p < 0.0001). There was also weak significant correlation also between HOMA-IR and selenium levels (r = −0.227, p = 0.003). There was a correlation between systolic blood pressure and BMI (r = 0.365, p < 0.0001). But there was no correlation between selenium levels and blood pressure or other parameters. HsCRP, HOMA-IR, homocysteine levels in individuals with selenium levels < 80 μg/L (n = 78) was significantly higher than hsCRP HOMA-IR, homocysteine levels in individuals with selenium levels ≥ 80 (n = 91; 1.23 ± 0.98 vs 0.81 ± 0.76 mg/dL, p < 0.003; 1.99 ± 0.88 vs 1.64 ± 0.74, p < 0.005; 15.0 ± 7.6 vs 12.9 ± 5.7 μmol/L, p < 0.049, respectively). Selenium deficiency may contribute to cardiovascular disease risk in FDR.  相似文献   
97.
Efficacy of selected adjuvants for protecting Spodoptera litura nucleopolyhedrovirus (SpltNPV) from sunlight inactivation was tested in direct sunlight exposure bioassays and in the field on virus-treated Brassica chinensis var parachinensis plants. All adjuvants, except palm oil, gave significant protection to the virus after 16 h of sunlight exposure, as shown by the larval mortalities. Cumulative mortalities after 14 days show that the virus + Tinopal treatment and the virus not to sunlight treatment attained 100% mortality, while the virus in riboflavin treatment and the crude brown sugar treatment caused mortality of less than 30%. However, the LT50 value of virus + Tinopal was 1.2 times lower than the unexposed virus. All virus-treated plants in the field trials had higher yields and lower damage indices than the control plants. Unlike the results from direct sunlight exposure bioassays, adjuvants, including virus + Tinopal LPW, did not significantly enhance efficacy of the virus against early instars of S. litura in the field. The unformulated virus was as effective as virus + Tinopal LPW and Nurelle-D in protecting the plants from infestation. Thus, in a well-planned pest management program, SpltNPV, without any adjuvant, can be used effectively for controlling S. litura on B. chinensis var parachinensis.  相似文献   
98.
Epizootic haemorrhagic disease virus (EHDV) infects wild ruminants, causing a frequently fatal haemorrhagic disease. However, it can also cause bluetongue-like disease in cattle, involving significant levels of morbidity and mortality, highlighting a need for more rapid and reliable diagnostic assays. EHDV outer-capsid protein VP2 (encoded by genome-segment 2 [Seg-2]) is highly variable and represents the primary target for neutralising antibodies generated by the mammalian host. Consequently VP2 is also the primary determinant of virus “serotype”, as identified in virus neutralisation tests (VNT). Although previous reports have indicated eight to ten EHDV serotypes, recent serological comparisons and molecular analyses of Seg-2 indicate only seven EHDV “types”. Oligonucleotide primers were developed targeting Seg-2, for use in conventional RT-PCR assays to detect and identify these seven types. These assays, which are more rapid and sensitive, still show complete agreement with VNT and were used to identify recent EHDV isolates from the Mediterranean region and North America.  相似文献   
99.
The aim of this study was to determine the serum levels of prolactin in patients with Behcet's disease and to evaluate its correlation with disease activity. Serum prolactin levels were measured by a chemiluminescence method in 32 patients with Behcet's disease and compared with 20 age-and sex-matched healthy controls. The patients with Behcet's disease were subdivided into two groups according to disease activity: active (18 patients; 13 men and five women, average age 34.0 +/- 6.5 (28-48) years), and inactive (14 patients; 10 men and four women, average age 32.7 +/- 3.1 (22-49 years). Patients with active Behcet's disease had higher serum prolactin levels than the inactive and control groups. Prolactin levels in patients with active Behcet's disease differed significantly from the healthy control subjects (p < 0.05) only, but not the inactive group. Four patients out of 32 (12.5%) Behcet's disease patients showed mild hyperprolactinemia. All four of these cases were from the active Behcet's disease group. Prolactin levels were correlated with ESR (p < 0.05) and CRP (p < 0.05) levels in the active BD group, but not in the inactive BD and control groups. Our results suggest a possible role for this immunoregulatory hormone in the disease expression and pathogenesis of Behcet's disease.  相似文献   
100.
The utilization of peptide ligands in biosensors and bioassays is dependent on achieving high affinity of these peptides toward their targets. In a previous report, we identified 12-mer peptides that could selectively bind to Staphylococcal enterotoxin B (SEB) using a phage-display library. In this study, we explore for new modification approaches to enhance the affinity of two different SEB-binding peptides. In order to identify the binding regions of selected peptides, the charged residues and the ones, critical for the structure of peptide, were replaced with alanine. However, a specific binding region could not be suggested as all mutant peptides have lost their affinities toward SEB completely. The modifications for the affinity enhancement were done by repeating the 12-mer peptide sequences. A 10-fold increase was observed in the binding affinity of one of the two-repeated peptides, while this modification did not affect the affinity of the other tested peptide. The peptide, with enhanced affinity, was further modified as three repeats; however the affinity of the peptide decreased. The structural basis of the affinity difference between modified peptides was examined by molecular dynamics simulation. The results showed that the conformational differences hold the key for affinity of peptides modified by repeating the sequence. This high affinity peptide with increased affinity is a promising molecular recognition agent to be used in the detection of SEB to be utilized in biosensing systems.  相似文献   
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