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991.
Previous studies have shown that selenium (Se) deficiency is associated with nutritional myopathy, known as white muscle disease (WMD), in horses. However, correlations between Se deficiency and clinical findings, such as hematologic biochemical values and pathological features, have not been evaluated in captive plains zebras. The purpose of the present study was to investigate the clinical and pathologic features that may be caused by a Se deficiency in the captive plains zebra. Clinical findings, feed analyses, hematologic biochemical analyses, response to treatment, and pathologic examination were assessed in six affected plains zebras. The dietary concentration of Se in feed was also tested. Sudden death occurred in two cases during the first day of the onset of symptoms. Two zebras died at 4 days and two zebras survived after treatment. The clinical signs in affected animals were characterized by general weakness, astasia, and abnormal postural positions. The Se concentration in hay from the breeding stable was low, based on the reference value. Glutathione peroxidase (GSH-Px) activity was lower compared with the equine reference value. Multiple areas of subcutaneous steatitis and pale skeletal muscle and myocardium were revealed at gross necropsy. Degeneration and necrosis of myocardial and skeletal muscles, as well as congestion of the liver, lung, and kidney were found via histopathological examination. No suspected bacterial infections were found. Feed analyses, response to treatment, serum GSH-Px activity, and pathological features suggest that Se deficiency may have caused the disease in the six affected captive plains zebra.  相似文献   
992.
993.
A new species of the genus Amolops Cope,1865 is described from Xinduqiao,Kangding,Sichuan.It was previously identified as Amolops kangtingensis,which is synonymized to Amolops mantzorum in this study.The new species,Amolops xinduqiao sp.nov.,is distinguished from all other congeners by the following combination of characters:(1) medium body size,adult males SVL 41.2-47.5 mm (n=15,average 43.9 mm),adult females SVL 48.5-56.6 mm (n=15,average 52.5 mm);(2) head length equal to width or slightly wider than long;(3) tympanum small,but distinct;(4) vomerine teeth in two tiny rows,separated by a space about one vomerine teeth row;(5) bony projections on lower jaw absent;(6) dorsolateral folds usually absent;(7) tarsal folds or glands on tarsus absent;(8) circummarginal groove on disc of finger Ⅰ absent;(9) tibiotarsal articulation reaching nostril or beyond;(10) webs of toe Ⅳ reaching to distal articulation,other toes fully webbed to disc;and (11) vocal sac absent in males.  相似文献   
994.
<正>This special issue of the journal is dedicated to the recent research progress on human herpesviruses(HHVs).Human herpesviruses are distributed worldwide,and more than 90%of adults are infected by one or multiple HHVs.The HHV family contains three sub-families:the alpha sub-family[herpes simplex virus 1(HSV-1),HSV-2,  相似文献   
995.
正Studies on influenza virus by Chinese Academy of Sciences(CAS)could be traced back as early as 2005 by the CAS Key Laboratory of Pathogenic Microbiology and Immunology(CASPMI),who discovered that Qinghai-like Clade 2.2H5N1 subtype highly pathogenic avian influenza virus(HPAIV)first caused severe outbreak in wild birds in Qinghai Lake(Liu et al.,2005).  相似文献   
996.
To investigate the effects of lentiviral vector‐mediated shRNA suppressing CXCR7 on tumour invasion and metastasis in hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). HCCLM3 cell lines were cultured and assigned into the CXCR7‐shRNA, negative control (NC) and blank groups. The qRT‐PCR and Western blotting were applied to detect the mRNA and protein expressions of CXCR7, CXCR4 and MMP‐2 in HCCLM3 cells. Cell proliferation and invasion were evaluated by MTT and Transwell assays. A Buffalo rat model of HCC was established. Fifty model rats were divided into the CXCR7‐shRNA + TACE, CXCR7‐shRNA, TACE, NC and control groups. Immunohistochemistry was performed to detect the expressions of CXCR7, MMP‐2, vascular endothelial growth factor (VEGF) and intratumoral CD31‐positive vessel count in tumour tissues of mice. Compared with the blank and NC groups, the mRNA and protein expressions of CXCR7 and MMP‐2 were decreased in the CXCR7‐shRNA group. The cell proliferation and invasion rates of the CXCR7‐shRNA group were lower than the blank and NC groups. At the 4th week after TACE, tumour weight of the CXCR7‐shRNA + TACE group increased continuously. The CXCR7‐shRNA + TACE group showed longer survival time and smaller tumour sizes than other groups. Compared with other groups, the CXCR7‐shRNA + TACE and CXCR7‐shRNA groups had less number of lung metastatic nodules and lower expressions of CXCR7, MMP‐2, VEGF and CD31‐positive vessel count. CXCR7‐shRNA inhibits tumour invasion and metastasis to improve the efficacy of TACE in HCC by reducing the expressions of CXCR7, MMP‐2 and VEGF.  相似文献   
997.
Sepsis remains a leading cause of death worldwide, despite advances in critical care, and understanding of the pathophysiology and treatment strategies. No specific therapy or drugs are available for sepsis. Neutrophils play a critical role in controlling infection under normal conditions, and it is suggested that their migration and antimicrobial activity are impaired during sepsis which contribute to the dysregulation of immune responses. Recent studies further demonstrated that interruption or reversal of the impaired migration and antimicrobial function of neutrophils improves the outcome of sepsis in animal models. In this review, we provide an overview of the associated mediators and signal pathways involved which govern the survival, migration and antimicrobial function of neutrophils in sepsis, and discuss the potential of neutrophils as a target to specifically diagnose and/or predict the outcome of sepsis.  相似文献   
998.
Aberrant microRNA expression is involved in the regulation of various cellular processes, such as proliferation and metastasis in multiple diseases including cancers. MicroRNA‐30e‐5p (miR‐30e) was previously reported as an oncogenic or tumour suppressing miRNA in some malignancies, but its function in lung adenocarcinoma (LAC) remains largely undefined. In this study, we found that the expression of miR‐30e was increased in LAC tissues and cell lines, associated with tumour size and represented an independent prognostic factor for overall survival and recurrence of LAC patients. Further functional experiments showed that knockdown of miR‐30e suppressed cell growth while its overexpression promoted growth of LAC cells and xenografts in vitro and in vivo. Mechanistically, PTPN13 was identified as the direct target of miR‐30e in LAC, in which PTPN13 expression was down‐regulated in LAC tissues and showed the inverse correlation with miR‐30e expression. Overexpression of PTPN13 inhibited cell growth and rescued the proliferation‐promoting effect of miR‐30e through inhibition of the EGFR signalling. Altogether, our findings suggest that miR‐30e could function as an oncogene in LAC via targeting PTPN13 and act as a potential therapeutic target for treating LAC.  相似文献   
999.
Learning the micro-mechanisms of fluorinated polymers during mechanical response is more difficult than that of common polymers due to the unique intrinsic characteristics of the fluorine element. In this paper, we applied molecular dynamics simulations to study deformation mechanisms of poly(vinylidine fluoride-co-chlorotrifluoroethylene) during uniaxial tension. We analyzed the variations of individual energy components and structural distribution curves versus strain in addition to the commonly used stress-strain curves and microstructure evolutions during stretching. The elastic limit is ??=?0.02, ??=?0.06 is the yield point, ??=?0.24 is the termination of the softening, necking occurs at 0.24?<???<?0.5, strain hardening occurs at 0.5?<???<?2.6, and ??=?2.6 is the damage or brake point. The elastic behavior of the material does not rely on strain rate, the obvious effect of strain rate can be seen at the yield region and strain softening region, and the stress values are not influenced by strain rates at the softening and hardening stages. Overall, total potential energy is mainly correlated with non-bonded energy, and the proportion of ΔEcoul overwhelms all the others. The energy components are ordered: ΔEcoul?>?ΔEvdwl >?>?ΔEangle?>?ΔEdihed?>?ΔEbond. The chain conformation at yield point is almost unchanged compared with the pre-stretching conformation. The chain conformations at the end of strain softening changes more obviously than that at yield point. The molecular chains maintain random coil structure before strain hardening, and switch into a stretch chain conformation gradually during strain hardening. The maximum change in bond angle during the stretching process is F-C-H, the largest change in bond length is the C-Cl bond, and the largest change in dihedral angle is H-C-C-H. The change of non-bonded interaction in the poly(VDF-co-CTFE) system is much larger than the bonding interaction, and the main factor affecting bonding interaction is the change of angles.
Graphical abstract Poly(vinylidine fluoride-co-chlorotrifluoroethylene) during tension?
  相似文献   
1000.
The high‐capacity cathode material V2O5·n H2O has attracted considerable attention for metal ion batteries due to the multielectron redox reaction during electrochemical processes. It has an expanded layer structure, which can host large ions or multivalent ions. However, structural instability and poor electronic and ionic conductivities greatly handicap its application. Here, in cell tests, self‐assembly V2O5·n H2O nanoflakes shows excellent electrochemical performance with either monovalent or multivalent cation intercalation. They are directly grown on a 3D conductive stainless steel mesh substrate via a simple and green hydrothermal method. Well‐layered nanoflakes are obtained after heat treatment at 300 °C (V2O5·0.3H2O). Nanoflakes with ultrathin flower petals deliver a stable capacity of 250 mA h g?1 in a Li‐ion cell, 110 mA h g?1 in a Na‐ion cell, and 80 mA h g?1 in an Al‐ion cell in their respective potential ranges (2.0–4.0 V for Li and Na‐ion batteries and 0.1–2.5 V for Al‐ion battery) after 100 cycles.  相似文献   
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