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Pulmonary pseudallescheriasis in an immunocompetent patient without a pre-existing cavity or cyst is a rare phenomenon. We
report a case of invasive pulmonary pseudallescheriasis in a lobectomised patient treated for tuberculosis. Filamentous fungi
with pyriform conidia were seen in the bronchoalveolar lavage fluid .The fungus was identified as Pseudallescheria boydii on culture. 相似文献
53.
An analytical expression for the drying time of thin lumber is derived, based on a method presented in this study. The laws of moisture content change in wood as function of mass transfer are used for the theoretical approach. The diffusion equation for moisture content is set up for a three-dimensional block of lumber based on the assumption of uniform initial distribution of moisture throughout the specimen. The boundary condition stipulates that the moisture gradient at the boundary is proportional to the deviation of the moisture content of the slab from the equilibrium value at that temperature. These conditions are used to derive an analytical expression for the time required to get from an initial moisture distribution to a desired final moisture content of thin lumber. For a sample calculation, the result of drying time agrees within 10% with the prediction of previously published analytical formulas for the drying curve. 相似文献
54.
Yu T Parks BW Yu S Srivastava R Gupta K Wu X Khaled S Chang PY Kabarowski JH Kucik DF 《Radiation research》2011,175(6):766-773
Radiation exposure from a number of terrestrial sources is associated with an increased risk for atherosclerosis. Recently, concern over whether exposure to cosmic radiation might pose a similar risk for astronauts has increased. To address this question, we examined the effect of 2 to 5 Gy iron ions ((56)Fe), a particularly damaging component of cosmic radiation, targeted to specific arterial sites in male apolipoprotein E-deficient (apoE(-/-)) mice. Radiation accelerated the development of atherosclerosis in irradiated portions of the aorta independent of any systemic effects on plasma lipid profiles or circulating leukocytes. Further, radiation exposure resulted in a more rapid progression of advanced aortic root lesions, characterized by larger necrotic cores associated with greater numbers of apoptotic macrophages and reduced lesional collagen compared to sham-treated mice. Intima media thickening of the carotid arteries was also exacerbated. Exposure to (56)Fe ions can therefore accelerate the development of atherosclerotic lesions and promote their progression to an advanced stage characterized by compositional changes indicative of increased thrombogenicity and instability. We conclude that the potential consequences of radiation exposure for astronauts on prolonged deep-space missions are a major concern. Knowledge gained from further studies with animal models should lead to a better understanding of the pathophysiological effects of accelerated ion radiation to better estimate atherogenic risk and develop appropriate countermeasures to mitigate its damaging effects. 相似文献
55.
Payabvash S Beheshtian A Salmasi AH Kiumehr S Ghahremani MH Tavangar SM Sabzevari O Dehpour AR 《Life sciences》2006,79(10):972-980
Recently many researchers have proposed a protective role for morphine against tumor growth and metastasis, especially through induction of apoptosis in tumoral cells. These findings may lead to underestimation of cytotoxic effects of opioid drugs which are usually expected only at high doses. The present study was conducted to clarify whether repeated morphine administration, which is commonly used for relief from chronic pain, would interfere with liver antioxidant defence and hepatocytes vitality. Morphine was injected repeatedly at doses that have been reported to relieve cancer pain and reduce tumor spread in mice (5 and 10 mg/kg/day for nine consecutive days). The changes in hepatic glutathione concentration, its synthesis pathway and enzymatic antioxidant defense revealed the pro-oxidant effects of chronic morphine treatment on the liver. None of these changes were observed in those mice that were co-treated with naltrexone (opioid antagonist) and same doses of morphine. However induction of liver conjugating enzymes following morphine treatment was not receptor mediated. Moreover, chronic morphine treatment induced hepatocytes apoptosis. Interestingly, the apoptotic changes were antagonized by co-administration of either naltrexone or thiol antioxidant. In conclusion, although hepatotoxic effects of morphine at high doses have been reported previously, our findings propose that repeated morphine administration even at lower doses would induce oxidative stress in the liver, which may contribute to induction of apoptosis in hepatocytes. Since many of the observed adverse effects were mediated by opioid receptors, our results suggest that other opioid analgesics should also be used more cautiously. 相似文献
56.
Sareh Rastipisheh Somayeh Nemati Maneezheh Pakravan Akhtar Tavassoli Saman Bolourian 《Feddes Repertorium》2016,127(1-2):7-13
With 600 species Ranunculus is the largest genus in Ranunculaceae, and has a broad global distribution. We studied the karyotypes of R. constantinopolitanus and R. sericeus species of Ranunculaceae and identified their symmetry level. New chromosome numbers of 2n = 21 (Nodeh woods population) and 2n ca. 63 (Javaherdeh population) are reported for R. constantinopolitanus. Two different populations of R. sericeus had two different chromosome results. We investigated morphological and karyological studies along with pollens micromorphology. Different populations of R. constantinopolitanus and R. sericeus, with different chromosome numbers showed morphological and micromorphological differences. Therefore, we considered the two populations of R. sericeus as cytotypes. There was a correlation between the studied morphological characters and pollen size with ploidy levels in the two R. constantinopolitanus populations. 相似文献
57.
Namvaran F Rahimi-Moghaddam P Azarpira N Nikeghbalian S 《Molecular biology reports》2012,39(3):3219-3223
Adiponectin which possesses anti-inflammatory and insulin-sensitizing properties is elevated in blood circulation of liver
cirrhosis patients. The genetic variations in the adiponectin gene can affect the circulating adiponectin level and stimulation
of adiponectin receptor that may affect the activity of adiponectin. We investigated the effect of adiponectin single nucleotide
polymorphisms (SNP) 45 T/G and adiponectin receptor-2 gene SNP 795G/A in cirrhotic Iranian population. A total of 97 cirrhotic
patients and 128 healthy controls from Iranian population were genotyped for the adiponectin and adiponectin receptor 2 gene
(+45T>G and 795G/A) by polymerase chain reaction-restriction fragment length polymorphism. G frequency was 21.1% versus 12.89%
(P = 0.001) for SNP45, and G frequency was 75.8% versus 76.2% (P = 0.526) for SNP795G/A in the patients and control group, respectively. Based on our findings, the expression of the G allele
at SNP45 is higher in the patient group compared with healthy subjects, suggesting that it may affect liver injury through
changes in the plasma adiponectin level. 相似文献
58.
Plant and Soil - Seeds are involved in the transmission of microorganisms from one plant generation to the next, acting as initial inoculum for the plant microbiome, therefore provide a key source... 相似文献
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