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161.
The cellular and molecular mechanisms that underlie skeletal abnormalities in defective Recql4-related syndromes are poorly understood. Our objective in this study was to explore the function of Recql4 in osteoblast biology both in vitro and in vivo. Immunohistochemistry on adult mouse bone showed Recql4 protein localization in active osteoblasts around growth plate, but not in fully differentiated osteocytes. Consistent with this finding, Recql4 gene expression was high in proliferating mouse osteoblastic MC3T3.E1 cells and decreased as cells progressively lost their proliferation activity during differentiation. Recql4 overexpression in osteoblastic cells exhibited higher proliferation activity, while its depletion impeded cell growth. In addition, bone marrow stromal cells from male Recql4+/- mice had fewer progenitor cells, including osteoprogenitors, indicated by reduced total fibroblast colony forming units (CFU-f) and alkaline phosphatase-positive CFU-f colonies concomitant with reduced bone mass. These findings provide evidence that Recql4 functions as a regulatory protein during osteoprogenitor proliferation, a critical cellular event during skeleton development.  相似文献   
162.
There has been considerable recent interest in proteomic analyses of plasma for the purpose of discovering biomarkers. Profiling N-linked glycopeptides is a particularly promising method because the population of N-linked glycosites represents the proteomes of plasma, the cell surface, and secreted proteins at very low redundancy and provides a compelling link between the tissue and plasma proteomes. Here, we describe UniPep http://www.unipep.org--a database of human N-linked glycosites--as a resource for biomarker discovery.  相似文献   
163.
Logistic regression was applied to develop a morphometric sexing method of two closely related stork species that were previously sexed through amplification of the CHD gene. Tarsus length (TL) and bill length (BL) measurements were recorded from captive populations of adult Milky Stork (Mycteria cinerea) (n = 60) and Painted Stork (Mycteria leucocephala) (n = 58) at Zoo Negara Malaysia. Despite having monomorphic plumages, both stork species exhibited normal sexual size dimorphism in which males were significantly larger than females in the tested variables. Based on logistic regression analysis, BL correctly classified the sex of sampled individuals from Painted and Milky stork with an overall predicted accuracy of 94.8 and 90.0%, respectively. However, TL measurements generated a lower predicted accuracy level of 86.2% and a same accuracy level of 90% on the sex classification of individuals from Painted and Milky stork, respectively. By comparing the measurements of both species, only the average BL measurements of the Milky storks were significantly lower than that of Painted storks (t-test, P80.001). The logistic regression equation in this study may serve as a simple and more practical option for sexing Milky and Painted storks for their breeding and conservation programmes.  相似文献   
164.
165.
Recently, there has been renewed interest in the role of reactive oxygen species (ROS), especially H(2)O(2), in wound healing. We previously showed that H(2)O(2) stimulates healing in a keratinocyte scratch wound model. In this paper, we used a more complex and physiologically relevant model that involves co-culturing primary keratinocytes and fibroblasts. We found that the two main cell types within the skin have different sensitivities to H(2)O(2) and to the widely used "antioxidant"N-acetyl-l-cysteine (NAC). Keratinocytes were very resistant to the toxicity of H(2)O(2) (250 and 500 μM) or NAC (5 mM). However, the viability of fibroblasts was decreased by both compounds. Using the co-culture model, we also found that H(2)O(2) increases re-epithelialization while NAC retards it. Our data further illustrate the possible role of ROS in wound healing and the co-culture model should be useful for screening agents that may influence the wound healing process.  相似文献   
166.
A rapid antibody detection test is very useful for the detection of lymphatic filariasis, especially for certification and surveillance of post-mass drug administration. panLF Rapid kit is suitable for this purpose since it can detect all species of lymphatic filaria. It is based on the detection of anti-filarial IgG4 antibodies that react with recombinant B. malayi antigens, BmR1 and BmSXP. There is an increase demand for the test due to its attributes of being rapid, sensitive and specific results, as well as its field-applicability. The main aim of this paper is to obtain high recovery and purity of recombinant antigen BmSXP via a modified method of immobilized metal affinity chromatography (IMAC). The highest product yield of 11.82 mg/g dry cell weight (DCW) was obtained when IMAC was performed using the optimized protocol of 10 mM imidazole concentration in lysis buffer, 30 mM imidazole concentration in wash buffer, and 10 column volume wash buffer containing 300 mM salt concentration. This gave a 54% protein recovery improvement over the manufacturer's protocol which recorded a product yield of only 7.68 mg/g DCW. The recovered BmSXP recombinant antigen showed good western blot reactivity, high sensitivity (31/32, 97%) and specificity (32/32, 100%) in ELISA, thus attesting to its good purity and quality.  相似文献   
167.
Two ternary Zn(II) complexes, with 1,10-phenanthroline (phen) as the main ligand and a carboxylate-containing ligand [dipicolinate (dipico) or L-threoninate (L-Thr)] as the subsidiary ligand, were prepared and characterized by elemental analysis, Fourier transform IR, UV, and fluorescence spectroscopy, X-ray diffraction, molar conductivity, and electrospray ionization mass spectrometry. X-ray structure analysis shows that both [Zn(phen)(dipico)(H(2)O)]·H(2)O (1) and [Zn(phen)(L-Thr)(H(2)O)Cl]·2H(2)O (2) have octahedral geometry about the Zn(II) atom. Both complexes can inhibit topoisomerase I, and have better anticancer activity than cisplatin against nasopharyngeal cancer cell lines, HK1 and HONE-1, with concentrations causing 50?% inhibition of cell proliferation (IC(50)) in the low micromolar range. Complex 2 has the highest therapeutic index for HK1. Both Zn(II) complexes can induce cell death by apoptosis. Changing the subsidiary ligand in the Zn(II) complexes affects the UV-fluorescence spectral properties of the coordinated phen ligand, the binding affinity for some DNA sequences, nucleobase sequence-selective binding, the phase at which cell cycle progression was arrested for treated cancer cells, and their therapeutic index.  相似文献   
168.
Curcuma longa L. has long been used as a medicinal plant in traditional Chinese medicine against abdominal disorders. Its active constituent curcumin has anti-inflammatory, chemopreventive and cytotoxic properties. In the present investigation, we have analyzed the cytotoxic activity of curcumin and four derivatives. Among these compounds, ethoxycurcumintrithiadiazolaminomethylcarbonate was the most cytotoxic one. The curcumin-type compounds were not cross-resistant to standard anticancer drugs and were not involved in ATP-binding cassette transporter-mediated multidrug resistance. A combined approach of messenger RNA-based microarray profiling, COMPARE analyses and signaling pathway analyses identified genes as determinants of sensitivity and resistance to curcumin and specific signaling routes involved in cellular response to curcumin. These genes may be useful as biomarkers to develop individualized treatment options in the future. From a nutritional point of view, it is a thriving perspective to further investigate whether C. longa may be used as a spice to improve cancer therapy.  相似文献   
169.
The aim of this study was to investigate the effect of processing route (i.e., quench cooling and ball milling) on the surface energy heterogeneity and surface chemistry of indomethacin (IMC). Recently developed inverse gas chromatography (IGC) methodology at finite concentrations was employed to determine the surface energy distributions of crystalline, quench cooled and milled IMC samples. Surface properties of crystalline and processed IMC were measurably different as determined by the IGC and other conventional characterization techniques: differential scanning calorimetry and powder X-ray diffraction. Quench cooled IMC was in fully amorphous form. Milled IMC showed no amorphous character by calorimetric or X-ray diffraction studies. It was demonstrated that both processed IMC samples were energetically more active than the crystalline IMC. In particular, milled IMC exhibited a relatively higher dispersive surface energy and higher surface basicity (electron donor capability). This may be attributed to the creation of surface defect sites or exposure of higher energy crystal facets during the milling process. This study confirms that processing route has notable influence on the surface energy distribution and surface acid–base character. IGC was demonstrated as a powerful technique for investigating surface properties of real-world, heterogeneous pharmaceutical materials.Key words: heterogeneity, indomethacin, inverse gas chromatography, surface disorder, surface energy  相似文献   
170.
YR Wu  LC Tan  X Fu  CM Chen  WL Au  L Chen  YC Chen  KM Prakash  Y Zheng  GJ Lee-Chen  Y Zhao  JS Zeng  EK Tan  Z Pei 《PloS one》2012,7(7):e36123
It has been suggested that a common LRRK2 polymorphic variant (A419V (rs34594498 C >T)) may be a risk factor among Asians (especially in Taiwan). In this study, we examined this variant in a larger and independent Taiwan cohort. We found the frequency of the variant (A419V) to be very rare in our Taiwan PD and controls (?0.6%). Further studies were conducted in two other Chinese populations (Singapore and China), comprising of a total of 3004 subjects including 1517 PD patients and 1487 control subjects. However, our multi-center Chinese study revealed that the frequency of the variant was rare (?0.4%) and was not associated with risk of PD, suggesting that the variant is not a major risk factor for PD among Chinese, at least in our study population.  相似文献   
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