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981.
Maria Heinrich Simona Botti Licia Caprara Wolfgang Arthofer Sabine Strommer Veronika Hanzer Hermann Katinger Assunta Bertaccini Margit Laimer Da Câmara Machado 《Plant Molecular Biology Reporter》2001,19(2):169-179
Phytoplasmas infecting fruit trees are considered quarantine organisms in Europe and North America. Detection often is hampered
by their extremely irregular distribution in host plants. A sensitive, specific and quick diagnostic test would be highly
desirable for routine detection, mainly to avoid using infected planting material. PCR methods require tedious preparation
of DNA; also, the available primers are highly specific and exhibit some homology to chloroplast and plastid DNA. To address
these problems, we compared several DNA preparation protocols for purity of DNA, cost and time required. We also developed
new primers using rDNA sequence information from an Austrian isolate of European Stone Fruit Yellows (ESFY). These primers
operate at high annealing temperatures and, thus, increase the specificity and decrease the risk of false positives. The primers
could reliably detect the European phytoplasmas (AP, ESFY and PD) within a collection of isolates maintained in micropropagated
periwinkle. Thus, they are suitable as general primers for phytoplasma detection. The primers also can be used for strain
identification by direct PCR followed by RFLP analysis as demonstrated with micropropagated fruit tree material. Finally,
an IC-PCR method that uses the primers for AP detection was found very sensitive and suitable for large-scale testing of apple
materialin vivo andin vitro. 相似文献
982.
Fabio Ponticelli Antoaneta Trendafilova Massimo Valoti Simona Saponara GianPietro Sgaragli 《Carbohydrate research》2001,330(4)
We describe the synthesis of some 3-tert-butyl-4-hydroxyphenyl
-glycopyranosides by reaction of tert-butylhydroquinone with β-
-pentaacetyl-glucose, β-
-pentaacetyl-galactose, 2-acetamido- and 3,4,6-tri-O-acetyl-2-butanamido-2-deoxy-β-
-glucopyranosyl chlorides as well as the formation of anomeric 3-tert-butyl-4-hydroxyphenyl 4,6-di-O-acetyl-2,3-dideoxy-
-erythro-hex-2-eno-pyranosides by reaction between tert-butylhydroquinone and 3,4,6-tri-O-acetyl-
-glucal. All compounds, except 3-tert-butyl-4-hydroxyphenyl α- and β-
-glucopyranosides, inhibited lipid peroxidation with a degree of potency comparable to that of tert-butyl hydroxyanisole. 相似文献
983.
984.
Sergio Esposito Graziella Massaro Vincenza Vona Vittoria Di Martino Rigano Simona Carfagna Carmelo Rigano 《Physiologia plantarum》2001,113(4):469-476
The effects of ammonium and glutamine supply on amino acid levels and the activity of glucose-6P dehydrogenase (G6PDH EC 1.1.1.49), the main regulated enzyme of the oxidative pentose phosphate pathway, were investigated in barley roots ( Hordeum vulgare cv. Alfeo). Feeding ammonium to barley plants increased the contents of glutamine, asparagine and G6PDH in roots. These effects were abolished by using inhibitors of glutamine synthetase. Glutamine-fed barley roots showed a similar increase in G6PDH activities to ammonium-fed plants. Two G6PDH enzymes (G6PDH 1 and 2) were partially purified and characterized from ammonium-fed and glutamine-fed roots. The isozymes had different pH optima and apparent Km values for glucose-6P. G6PDH 2 showed similar kinetic parameters to the G6PDH present in root extracts of barley grown without any nitrogen source, while G6PDH 1 exhibited different kinetic parameters, suggesting the appearance of a second G6PDH isoform in response to ammonium. Western blot analysis demonstrated the existence of two G6PDH subunits of different molecular mass in barley roots grown in the presence of ammonium or glutamine, while only one isoform could be detected in roots grown without any nitrogen source. The results suggest a primary role of ammonium and/or glutamine in the appearance of a novel G6PDH isoform; this enzyme (G6PDH 1) shows kinetic parameters similar to those measured previously for chloroplastic and plastidic isoforms and seems to be induced by changes in glutamine content or a related compound(s) in the roots. 相似文献
985.
986.
Antonella Vetuschi Alfredo Cappariello Paolo Onori Eugenio Gaudio Giovanni Latella Simona Pompili Roberta Sferra 《European journal of histochemistry : EJH》2022,66(3)
Cellular senescence and ferroptosis are the two main, fine-tuned processes in tissue damage restraint; however, they can be overactivated in pathologies such as nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH), becoming dangerous stimuli. Senescence is characterized by a decline in cell division and an abnormal release of reactive oxygen species (ROS), and ferroptosis is represented by iron deposition associated with an excessive accumulation of ROS. ROS and cellular stress pathways are also drivers of NAFLD/NASH development. The etiology of NAFLD/NASH lies in poor diets enriched in fat and sugar. This food regimen leads to liver steatosis, resulting in progressive degeneration of the organ, with a late onset of irreversible fibrosis and cirrhosis. Few studies have investigated the possible connection between senescence and ferroptosis in NAFLD/NASH progression, despite the two events sharing some molecular players. We hypothesized a possible link between senescence and ferroptosis in a NAFLD background. To thoroughly investigate this in the context of “Western-style” diet (WSD) abuse, we used an amylin-modified liver NASH mouse model. The main NASH hallmarks have been confirmed in this model, as well as an increase in apoptosis, and Ki-67 and p53 expression in the liver. Senescent beta-galactosidase-positive cells were elevated, as well as the expression of the related secretory molecules Il-6 and MMP-1. Features of DNA damage and iron-overload were found in the livers of NASH mice. Gpx4 (glutathione peroxidase 4) expression, counteracting ferroptotic cell death, was increased. Notably, an increased number of senescent cells showing overexpression of gpx4 was also found. Our data seem to suggest that senescent cells acquire a gpx4-mediated mechanism of ferroptosis resistance and thus remain in the liver, fostering the deterioration of liver fitness.Key words: NAFLD/NASH, senescence, ferroptosis, beta-galactosidase, gpx4 相似文献
987.
988.
Claudia Menichelli Franco Casamassima Cynthia Aristei Gianluca Ingrosso Simona Borghesi Fabio Arcidiacono Valentina Lancellotta Ciro Franzese Stefano Arcangeli 《Reports of Practical Oncology and Radiotherapy》2022,27(1):32
The liver is the first metastatic site in 15–25% of colorectal cancer patients and one of the first metastatic sites for lung and breast cancer patients.A computed tomography (CT ) scan with contrast medium is a standard procedure for assessing liver lesions but magnetic resonance imaging (MRI) characterizes small lesions better thanks to its high soft-tissue contrast. Positron emission tomography with computed tomography (PET-CT ) plays a complementary role in the diagnosis of liver metastases. Triphasic (arterial, venous and time-delayed) acquisition of contrast-medium CT images is the first step in treatment planning. Since the liver exhibits a relatively wide mobility due to respiratory movements and bowel filling, appropriate techniques are needed for target identification and motion management. Contouring requires precise recognition of target lesion edges. Information from contrast MRI and/or PET-CT is crucial as they best visualize metastatic disease in the parenchyma. Even though different fractionation schedules were reported, doses and fractionation schedules for liver stereotactic radiotherapy (SRT ) have not yet been established. The best local control rates were obtained with BED10 values over 100 Gy. Local control rates from most retrospective studies, which were limited by short follow-ups and included different primary tumors with intrinsic heterogeneity, ranged from 60% to 90% at 1 and 2 years. The most common SRT-related toxicities are increases in liver enzymes, hyperbilirubinemia and hypoalbuminemia. Overall, late toxicity is mild even in long-term follow-ups. 相似文献
989.
Myosin VI regulates ciliogenesis by promoting the turnover of the centrosomal/satellite protein OFD1
Elisa Magistrati Giorgia Maestrini Carlos A Nio Mariana LinceFaria Galina Beznoussenko Alexandre Mironov Elena Maspero Mnica BettencourtDias Simona Polo 《EMBO reports》2022,23(3)
The actin motor protein myosin VI is a multivalent protein with diverse functions. Here, we identified and characterised a myosin VI ubiquitous interactor, the oral‐facial‐digital syndrome 1 (OFD1) protein, whose mutations cause malformations of the face, oral cavity, digits and polycystic kidney disease. We found that myosin VI regulates the localisation of OFD1 at the centrioles and, as a consequence, the recruitment of the distal appendage protein Cep164. Myosin VI depletion in non‐tumoural cell lines causes an aberrant localisation of OFD1 along the centriolar walls, which is due to a reduction in the OFD1 mobile fraction. Finally, loss of myosin VI triggers a severe defect in ciliogenesis that could be, at least partially, ascribed to an impairment in the autophagic removal of OFD1 from satellites. Altogether, our results highlight an unprecedent layer of regulation of OFD1 and a pivotal role of myosin VI in coordinating the formation of the distal appendages and primary cilium with important implications for the genetic disorders known as ciliopathies. 相似文献
990.