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991.
Toxoplasma gondii oocysts spread in the environment are an important source of toxoplasmosis for humans and animal species. Although the life expectancy of oocysts has been studied through the infectivity of inoculated soil samples, the survival dynamics of oocysts in the environment are poorly documented. The aim of this study was to quantify oocyst viability in soil over time under two rain conditions. Oocysts were placed in 54 sentinel chambers containing soil and 18 sealed water tubes, all settled in two containers filled with soil. Containers were watered to simulate rain levels of arid and wet climates and kept at stable temperature for 21.5 months. At nine sampling dates during this period, we sampled six chambers and two water tubes. Three methods were used to measure oocyst viability: microscopic counting, quantitative PCR (qPCR), and mouse inoculation. In parallel, oocysts were kept refrigerated during the same period to analyze their detectability over time. Microscopic counting, qPCR, and mouse inoculation all showed decreasing values over time and highly significant differences between the decreases under dry and damp conditions. The proportion of oocysts surviving after 100 days was estimated to be 7.4% (95% confidence interval [95% CI] = 5.1, 10.8) under dry conditions and 43.7% (5% CI = 35.6, 53.5) under damp conditions. The detectability of oocysts by qPCR over time decreased by 0.5 cycle threshold per 100 days. Finally, a strong correlation between qPCR results and the dose infecting 50% of mice was found; thus, qPCR results may be used as an estimate of the infectivity of soil samples.  相似文献   
992.
Molecular targets in prostate cancer are continually being explored, for which there are currently few therapeutic options. Rapamycin (RPM) is an antifungal macrolide antibiotic isolated from Streptomyces hygroscopicus which can inhibit the G1 to S transition. URGCP (upregulator of cell proliferation) is a novel gene located on chromosome 7p13. We aimed to investigate the role of URGCP gene expression changes in PC3, DU145, and LNCAP cell lines with/out RPM. Average cell viability and cytotoxic effect of rapamycin were investigated at 24?h intervals for three days by using Trypan blue dye exclusion test and XTT assay. Cytotoxic effects of rapamycin in DU145, PC3 and LNCAP cells were detected in time and dose dependent manner with the IC50 doses within the range of 1–100?nM. As the results were evaluated, IC50 doses in the DU145, PC3, and LNCaP cells were detected as 10, 25, and 50?nM, respectively. The mean relative ratios of URGCP gene expression in DU145, LNCAP and PC3 cells were found as ?1.48, 6.59 and ?13.00, respectively, when compared to rapamycin-free cells. The False Discovery Rate adjusted p value in DU145, LNCAP and PC3 were 1.25?×?10?5, 2.20?×?10?8 and 6.20?×?10?9, respectively. When the URGCP gene expression level is compared between the dose and control group, we found that URGCP gene expression was significantly decreased in dose groups of DU145 and PC3 cells.  相似文献   
993.
The genotoxic effects of antimicrobial food additive sodium sorbate (SS) was assessed by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), and micronucleus (MN) in cultured human lymphocytes and comet assay in isolated human lymphocytes. Lymphocytes were treated with four concentrations (100, 200, 400 and 800 μg/ml) of SS as well as a negative (sterile distilled water) and a positive control (Mitomycin-C: MMC for cultured lymphocytes and H2O2 for isolated lymphocytes). The result of this study indicated that SS increased the frequency of CAs at both 24 and 48 h period compared to control. When gaps were included, this increase was significant at 200, 400 and 800 μg/ml concentrations at 24 h and, at all concentrations at 48 h treatment time. When gaps were excluded, this increase was significant at only 800 μg/ml concentration at both 24 and 48 h treatments. In addition, SS increased SCEs/cell and MN frequency at 400 and 800 μg/ml concentrations at both 24 and 48 h compared to negative control. Furthermore, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1 h in vitro exposure. The present results show that SS is genotoxic to the human peripheral blood lymphocytes in vitro at the highest concentrations.  相似文献   
994.
Diabetes mellitus, a debilitating chronic disease, affects ~100?million people. Peripheral neuropathy is one of the most common early complications of diabetes in ~66?% of these patients. Altered Ca(2+) handling and Ca(2+) signaling were detected in a huge variety of preparations isolated from animals with experimentally induced type 1 and 2 diabetes as well as patients suffering from the disease. We reviewed the role of Ca(2+) signaling through cation channels and oxidative stress on diabetic neuropathic pain in sensory neurons. The pathogenesis of diabetic neuropathy involves the polyol pathway, advanced glycation end products, oxidative stress, protein kinase C activation, neurotrophism, and hypoxia. Experimental studies with respect to oxidative stress and Ca(2+) signaling, inhibitor roles of antioxidants in diabetic neuropathic pain are also summarized in the review. We hypothesize that deficits in insulin, triggers alterations of sensory neurone phenotype that are critical for the development of abnormal Ca(2+) homeostasis and oxidative stress and associated mitochondrial dysfunction. The transient receptor potential channels are a large family of proteins with six main subfamilies. The sheer number of different TRPs with distinct functions supports the statement that these channels are involved in a wide range of processes ranging in diabetic neuropathic pain and it seems that the TRPC, TRPM and TRPV groups are mostly responsible from diabetic neuropathic pain. In conclusion, the accumulating evidence implicating Ca(2+) dysregulation and over production of oxidative stress products in diabetic neuropathic pains, along with recent advances in understanding of genetic variations in cation channels such as TRP channels, makes modulation of neuronal Ca(2+) handling an increasingly viable approach for therapeutic interventions against the painful and degenerative aspects of many diabetic neuropathies.  相似文献   
995.
Ca(2+) is well known for its role as crucial second messenger in modulating many cellular physiological functions, Ca(2+) overload is detrimental to cellular function and may present as an important cause of cellular oxidative stress generation and apoptosis. The aim of this study is to investigate the effects of selenium on lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GSH-Px), cytosolic Ca(2+) release, cell viability (MTT) and apoptosis values in dorsal root ganglion (DRG) sensory neurons of rats. DRG cells were divided into four groups namely control, H(2)O(2) (as a model substance used as a paradigm for oxidative stress), selenium, selenium + H(2)O(2). Moderate doses and times of H(2)O(2) and selenium were determined by MTT test. Cells were preterated 200 nM selenium for 30 h before incubatation with 1 μM H(2)O(2) for 2 h. Lipid peroxidation levels were lower in the control, selenium, selenium + H(2)O(2) groups than in the H(2)O(2) group. GSH-Px activities were higher in the selenium groups than in the H(2)O(2) group. GSH levels were higher in the control, selenium, selenium + H(2)O(2) groups than in the H(2)O(2) group. Cytosolic Ca(2+) release was higher in the H(2)O(2) group than in the control, selenium, selenium + H(2)O(2) groups. Cytosolic Ca(2+) release was lower in the selenium + H(2)O(2) group than in the H(2)O(2). In conclusion, the present study demonstrates that selenium induced protective effects on oxidative stress, [Ca(2+)](c) release and apoptosis in DRG cells. Since selenium deficiency is a common feature of oxidative stress-induced neurological diseases of sensory neurons, our findings are relevant to the etiology of pathology in oxidative stress-induced neurological diseases of the DRG neurons.  相似文献   
996.
This study examined firstly the possible association of G241R and K469E single nucleotide polymorphisms (SNPs) of ICAM-1 gene with the occurrence of Hashimoto thyroiditis (HT). G241R and K469E SNPs in DNA from peripheral blood leukocytes of 190 HT and 247 healthy controls were investigated by real-time PCR combined with melting curve analysis using fluorescence-labeled hybridization probes. There was a significant increase of ICAM-1 241R allele frequency in patients with HT compared with healthy controls (P?=?0.04, OR?=?1.84, 95?% CI?=?1.00–3.37). Regarding ICAM-1 K469E polymorphism, patients homozygous for E allele had 1.73–fold increased risk for developing HT according to KK homozygotes (P?=?0.04, 95?% CI?=?1.00–3.01). The 469E allele frequency was higher in HT patients according to controls, however the difference was at borderline significance (P?=?0.05, OR?=?1.30, 95?% CI?=?1.00–1.70). No associations between polymorphisms and HT phenotypes were observed. We suggest that the G241R and K469E SNPs of ICAM-1 gene may be related to occurrence of HT. However, more studies with larger sample size including other loci of the ICAM-1 gene are necessary to support our findings before any definite statement can be made about the relationship between HT and ICAM-1 polymorphism.  相似文献   
997.
Knowledge regarding the spatial behavior of the Eurasian lynx is mainly inferred from populations in Europe. We used GPS telemetry to record the spatial behavior of nine individuals in northwestern Anatolia obtaining eleven home ranges (HRs). Analyses revealed the smallest mean HR sizes (nHR  = 4) at 57 km2 (95% kernel utilization distribution, KUD) and 56 km2 (95% minimum convex polygon, MCP), ever reported for adult female Eurasian lynx. Adult males either occupied small permanent territories (nHR♂.T = 2), with a mean of 176 km2 (95% KUD) and 150 km2 (95% MCP), or were residents without territories (floaters, nHR♂. F  = 2) roaming across large, stable HRs with a mean size of 2,419 km2 (95% KUD) and 1,888 km2 (95% MCP), comparable to HR sizes of Scandinavian lynx populations. Three disperser subadult males did not hold stable HRs (mean 95% KUD = 203 km2, mean 95% MCP = 272 km2). At 4.9 individuals per 100 km2, population density was one of the highest recorded, suggesting that the presence of adult male floaters was a consequence of a landscape fully occupied by territorials and revealing a flexibility of spatial behavior of Eurasian lynx not previously recognized. Such a high population density, small HRs, and behavioral flexibility may have been aided by the legal protection from and apparent low levels of poaching of this population. The observed spatial tactics are unlikely to be seen in most of the previously studied Eurasian lynx populations, as they either suffer medium to high levels of human‐caused mortality or were unlikely to be at carrying capacity. For effective and appropriate conservation planning, data from felid populations in a reasonably natural state such as ours, where space, density, prey, and pathogens are likely to be the key drivers of spatial dynamics, are therefore essential.  相似文献   
998.
Age-related macular degeneration (AMD) is a disease with multifactorial etiology characterized by irreversible loss of central visual acuity. The discovery of susceptive single-nucleotide polymorphisms (SNPs) has progressed our understanding of AMD. Complement factor H (CFH) gene Y402H polymorphism and high-temperature requirement A-1 (HTRA1) LOC387715 gene A69S polymorphisms are the most important SNPs reported in the literature. Determination of genetic risk factors and genotype-phenotype relationship in AMD may result in rapid and cost-effective therapeutic applications for young and old population. In this study, we hypothesized a potential association between CFH gene Y402H and HTRA1 LOC387715 gene A69S polymorphism in Turkish AMD patients. In blood samples from a total of 252 individuals, 147 clinically diagnosed as AMD and the others control, polymorphic sites in CFH, Y402H (Tsp509I T/C), and HTRA1, LOC387715 A69S (FnuHI G/T), were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. There was significant difference between CFH genotypes in the AMD group, TT 21.8%, TC 48.3%, and CC 29.9%, and in the control subjects, TT 45% (p=0.003), TC 41% (p=0.0001), and CC 14% (p=0.0001). Further, the A69S polymorphism of LOC387715 was investigated and found to be significantly associated with AMD. LOC387715 genotypes in the AMD group were GG 30.6%, GT 38.1%, and TT 31.3% and in the control subjects were GG 59% (p=0.027), GT 39% (p=0.0001), and TT 2% (p=0.0001), respectively. We also found that Y402H C and A69S T allele were associated with AMD. This is the first study showing that Y402H and LOC387715 are associated with AMD in Turkish population.  相似文献   
999.
ABSTRACT: K?klü, Y, Ers?z, G, Alemdaro?lu, U, A???, A, and ?zkan, A. Physiological responses and time-motion characteristics of 4-A-side small-sided game in young soccer players: The influence of different team formation methods. J Strength Cond Res 26(11): 3118-3123, 2012-The purpose of this study was to examine the influence of different team formation methods on the physiological responses to and time-motion characteristics of 4-a-side small-sided games (SSG4) in young soccer players. Thirty-two young soccer players (age 16.2 ± 0.7 years; height 172.9 ± 6.1 cm; body mass 64.1 ± 7.7 kg) voluntarily participated in this study. Anthropometric measurements, technical tests, and maximum oxygen uptake (V[Combining Dot Above]O2max) tests were carried out on the players. The SSG4 teams were then created using 4 different methods: according to the coaches' subjective evaluation (CE), technical scores (TS), V[Combining Dot Above]O2max (AP), and V[Combining Dot Above]O2max multiplied by TSs (CG). The teams thus created played 4 bouts of SSG4 at 2-day intervals. During the SSG4, heart rate (HR) responses, distance covered, and time spent in HRmax zones were recorded. In addition, rating of perceived exertion (RPE) and blood lactate level (La) were determined at the end of the last bout of each SSG4. Percent of HRmax (%HRmax), La, and RPE responses during SSG4 were significantly higher for teams chosen according to AP and CG compared with that according to CE and TS (p < 0.05). In addition, teams chosen by AP and CG spent significantly more time in zone 4 (>90% HRmax ) and covered a greater distance in the high-intensity running zone (>18 km·h) than did teams formed according to TS. Moreover, AP teams covered significantly greater total distance than TS teams did (p < 0.05). In conclusion, to spend more time in both the high-intensity HR zone and the high-intensity running zone, the teams in SSG4 should be formed according to the players' V[Combining Dot Above]O2max values or the values calculated using both the V[Combining Dot Above]O2max and technique scores.  相似文献   
1000.
Electrode materials play a key role in enhancing the electricity generation in the microbial fuel cell (MFC). In this study, a new material (Ti-TiO(2)) was used as an anode electrode and compared with a graphite electrode for electricity generation. Current densities were 476.6 and 31 mA/m(2) for Ti-TiO(2) and graphite electrodes, respectively. The PCR-DGGE analysis of enriched microbial communities from estuary revealed that MFC reactors were dominated by Shewanella haliotis, Enterococcus sp., and Enterobacter sp. Bioelectrochemical kinetic works in the MFC with Ti-TiO(2) electrode revealed that the parameters by non-linear curve fitting with the confidence bounds of 95% gave good fit with the kinetic constants of η (difference between the anode potential and anode potential giving one-half of the maximum current density) = 0.35 V, K (s) (Half-saturation constant) = 2.93 mM and J (max) = 0.39 A/m(2) for T = 298 K and F = 96.485 C/mol-e(-). From the results observed, it is clear that Ti-TiO(2) electrode is a promising candidate for electricity generation in MFC.  相似文献   
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