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381.
Type 2 cytokines (IL-4, IL-5, and IL-13) play a pivotal role in helminthic infection and allergic disorders. CD4(+) T cells which produce type 2 cytokines can be generated via IL-4-dependent and -independent pathways. Although the IL-4-dependent pathway is well documented, factors that drive IL-4-independent Th2 cell differentiation remain obscure. We report here that the new cytokine IL-33, in the presence of Ag, polarizes murine and human naive CD4(+) T cells into a population of T cells which produce mainly IL-5 but not IL-4. This polarization requires IL-1R-related molecule and MyD88 but not IL-4 or STAT6. The IL-33-induced T cell differentiation is also dependent on the phosphorylation of MAPKs and NF-kappaB but not the induction of GATA3 or T-bet. In vivo, ST2(-/-) mice developed attenuated airway inflammation and IL-5 production in a murine model of asthma. Conversely, IL-33 administration induced the IL-5-producing T cells and exacerbated allergen-induced airway inflammation in wild-type as well as IL-4(-/-) mice. Finally, adoptive transfer of IL-33-polarized IL-5(+)IL-4(-)T cells triggered airway inflammation in naive IL-4(-/-) mice. Thus, we demonstrate here that, in the presence of Ag, IL-33 induces IL-5-producing T cells and promotes airway inflammation independent of IL-4.  相似文献   
382.
Diverse food wastes, apple, orange and potato, were screened for laccase production, under solid-state fermentation conditions, by the white-rot fungus Trametes hirsuta. Potato peelings gave the highest activity, reaching about 5000 U l–1 within 8 days. These values are higher than those reported to date.  相似文献   
383.
Citral, myrcene and limonene (100 and 200 mg/kg body wt., i.p.), constituents of essential oils from Lippia alba chemotypes, decreased not only the number of crossings but also numbers for rearing and grooming, as measured by the open-field test in mice. Although muscle relaxation detected by the rota rod test was seen only at the highest doses of citral (200 mg/kg body wt.) and myrcene (100 and 200 mg/kg body wt.), this effect was observed even at the lowest dose of limonene (50 mg/kg body wt.). Also, citral and myrcene (100 and 200 mg/kg body wt.) increased barbiturate sleeping time as compared to control. Limonene was also effective at the highest dose, and although citral did not increase the onset of sleep, it increased the duration of sleep, which is indicative of a potentiation of sleeping time. Citral (100 and 200 mg/kg body wt.) increased 2.3 and 3.5 times, respectively, the barbiturate sleeping time in mice. Similar effects were observed for myrcene and limonene at the highest dose (200 mg/kg body wt.) which increased the sleeping time around 2.6 times. In the elevated-plus maze, no effect was detected with citral up to 25 mg/kg body wt., while at a high dose it decreased by 46% the number of entries in the open arms. A smaller but significant effect was detected with limonene (5 mg/kg body wt.). While myrcene (10 mg/kg body wt.) decreased only by 22% the number of entries in the open arms, this parameter was decreased by 48% at the highest dose. Our study showed that citral, limonene and myrcene presented sedative as well as motor relaxant effects. Although only at the highest dose, they also produced a potentiation of the pentobarbital-induced sleeping time in mice, which was more intense in the presence of citral. In addition, neither of them showed an anxiolytic effect, but rather a slight anxiogenic type of effect at the higher doses.  相似文献   
384.
Maximum activities of manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP) in free cultures of Phanerochaete chrysosporium (ATCC 24725) were 258 U l–1 and 103 U l–1, respectively, in an airlift bioreactor. Immobilisation of the fungus on an inert carrier as well as several design modifications of the bioreactor employed gave MnP activities around 500–600 U l–1 during 9 days' operation. The continuous operation of the latter led to MnP and LiP activities about 140 U l–1 and 100 U l–1, respectively, for two months, without operational problems. Furthermore, the extracellular liquid secreted decolourised the polymeric dye Poly R-478 about 56%.  相似文献   
385.

Background

The study of neoplasia in wildlife species contributes to the understanding of cancer biology, management practices, and comparative pathology. Higher frequencies of neoplasms among captive non-domestic felids have been reported most commonly in aging individuals. However, testicular tumours have rarely been reported. This report describes a metastatic testicular sex cord–stromal tumour leading to fatal haemorrhage and thrombosis in a captive African lion (Panthera leo).

Case presentation

During necropsy of a 16-year-old male African lion, the left testicle and spermatic cord were found to be intra-abdominal (cryptorchid), semi-hard and grossly enlarged with multiple pale-yellow masses. Encapsulated haemorrhage was present in the retroperitoneum around the kidneys. Neoplastic thrombosis was found at the renal veins opening into the caudal vena cava. Metastases were observed in the lungs and mediastinal lymph nodes. Histology revealed a poorly differentiated pleomorphic neoplasm comprised of round to polygonal cells and scattered spindle cells with eosinophilic cytoplasm. An immunohistochemistry panel of inhibin-α, Ki-67, human placental alkaline phosphatase, cytokeratin AE1/AE3, cKit, vimentin and S100 was conducted. Positive cytoplasmic immunolabeling was obtained for vimentin and S100.

Conclusions

The gross, microscopic and immunohistochemical findings of the neoplasm were compatible with a poorly differentiated pleomorphic sex cord–stromal tumour. Cause of death was hypovolemic shock from extensive retroperitoneal haemorrhage and neoplastic thrombosis may have contributed to the fatal outcome. To our knowledge, this is the first report of sex cord–stromal tumour in non-domestic felids.
  相似文献   
386.
387.
Lethal concentration (LC) has been widely used to estimate pesticide toxicity. However, it does not consider the sub-lethal effects. Therefore we included the instantaneous rate of increase in association with LC to estimate population-level effects of the acaricides fenbutatin oxide and sulfur on the predator Iphiseiodes zuluagai and its prey, the phytophagous southern red mite, Oligonychus ilicis. The predator was 32.84x and 17.20x more tolerant to fenbutatin oxide and sulfur, respectively, than its prey, based on LC50 estimates obtained from acute concentration–mortality bioassays. The instantaneous rate of population growth in both mite species decreased with increasing acaricide concentration. Both acaricides provided effective control of O. ilicis at their recommended concentrations, but sulfur drastically compromised the predator populations quickly leading them to extinction due to the low reproductive potential of this species compared with its prey.  相似文献   
388.
Entomopathogenic fungi are widely produced for use as mycoinsecticides. Therefore, improvement of the shelf life of fungal propagules under good and adverse conditions should be a pre-requisite of their production. In order to improve conidial physiology as well as mycoinsecticide efficiency, culture conditions may be varied. The Doehlert design was used to generate response surfaces with an estimation of the parameters of the quadratic model allowing the study of three different factors at a different number of levels. This experimental design was applied to optimize water activity (a w), pH, and fermentation time for Beauveria bassiana conidial production and accumulation of polyols in solid-state fermentation. Thus, it was possible to identify the region in the experimental range in which the optimum values of these parameters were simultaneously achieved. Maximal conidia production was achieved at pH 5–6 and a w=0.999. Under these conditions, polyol accumulation was 3 mg erythritol/g conidia and 29.6 mg glycerol/g conidia. However, maximal polyol accumulation was achieved at pH 4.5 and a w 0.950; erythritol production increased 33-fold and glycerol production 4.5-fold. Under these conditions conidia production was 1,000 times lower. The possibilities of increasing the quality of the biocontrol agent without neglecting yield are discussed.  相似文献   
389.
AIMS: The development of a simple and reliable procedure, compatible with routine use in wineries, for the presumptive detection of Brettanomyces/Dekkera from wine and wine-environment samples. METHODS AND RESULTS: The method of detection of these yeasts employs a selective enrichment medium. The medium contains glucose (10 g l(-1)) as carbon and energy source, cycloheximide (20 mg l(-1)) to prevent growth of Saccharomyces, chloramphenicol (200 mg l(-1)) to prevent growth of bacteria and p-coumaric acid (20 mg l(-1)) as the precursor for the production of 4-ethyl-phenol. After the inoculation with wine, the medium is monitored by visual inspection of turbidity and by periodic olfactive analysis. Contaminated wines will develop visible turbidity in the medium and will produce the 4-ethyl-phenol off-odour, which can be easily detected by smelling. CONCLUSIONS: A selective enrichment liquid medium was developed to differentially promote the growth and activity of Brettanomyces/Dekkera. The method is simple to execute, employing a simple-to-prepare medium and a periodic olfactive detection. SIGNIFICANCE AND IMPACT OF THE STUDY: The characteristics of the procedure make it particularly applicable in a wine-making environment thus presenting important advantages to the wine industry.  相似文献   
390.
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