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101.
Cells from bacteria to man respond to sublethal thermal and certain chemical stresses by synthesis of heat shock, or stress, proteins. The human epidermal keratinocyte is a target for a variety of cytotoxic substances. One response of cells exposed to such agents may be the synthesis of stress proteins. Human epidermal keratinocytes were treated thermally (43°C) or chemically with sodium arsenite and the skin irritants phenyldichloroarsine and mechlorethamine. Proteins synthesized by keratinocytes were radiolabeled with [35S]methionine, separated on polyacrylamide gels under denaturing conditions, and visualized by fluorography. Quantitation by computer-assisted densitometry of fluorograms revealed different patterns of synthesis of two heat shock proteins (hsp's) with apparent molecular weights of 70 and 90 kDa after treatment with heat, sodium arsenite, phenyldichloroarsine, or mechlorethamine. Sodium arsenite induced the highest levels of synthesis of these two proteins, approximately 10-fold and 3-fold increases in hsp-70 and hsp-90, respectively. Phenyldichloroarsine at 0.5 μm produced a 2-fold increase in hsp-70 but no significant increase in hsp-90. Mechlorethamine, in contrast, had an apparent inhibitory effect on hsp-70 synthesis. These results suggest that some but not all skin irritants induce the synthesis of heat shock proteins in human keratinocytes.  相似文献   
102.
ContextThe bulb of Lilium brownii F. E. Brown (Liliaceae) (LB) is a common Chinese medicine to relieve insomnia.ObjectiveTo investigate the molecular mechanism of LB relieving insomnia.Materials and methodsInsomnia model was induced by intraperitoneally injection p-chlorophenylalanine (PCPA) in Wistar rats. Rats were divided into three groups: Control, PCPA (400 mg/kg, i.p. 2 days), LB (598.64 mg/kg, oral 7 days). The levels of 5-hydroxytryptamine (5-HT), norepinephrine (NE), melatonin (MT), and the expression of GABAA, 5-HT1A and MT receptors, as well as pathological changes in hypothalamus, were evaluated. 16S rDNA sequencing and UPLC-MS/MS were used to reveal the change of the intestinal flora and metabolic profile.ResultsThe adverse changes in the abundance and diversity of intestinal flora and faecal metabolic phenotype altered by PCPA in rats were reversed after LB treatment, accompanied by the up-regulated levels of 5-HT as 8.14 ng/mL, MT as 16.16 pg/mL, 5-HT1A R and GABAA R, down-regulated level of NE as 0.47 ng/mL, and the improvement of pathological phenomena of cells in the hypothalamus. And the arachidonic acid metabolism and tryptophan metabolism pathway most significantly altered by PCPA were markedly regulated by LB. Besides, it was also found that LB reduced the levels of kynurenic acid related to psychiatric disorders and trimethylamine-N-oxide associated with cardiovascular disease.ConclusionThe mechanism of LB relieving insomnia involves regulating flora and metabolites to resemble the control group. As a medicinal and edible herb, LB could be considered for development as a health-care food to relieve increasing insomniacs in the future.  相似文献   
103.
杨秀伟  张鹏 《中国现代中药》2023,25(5):1105-1112
妇科千金方是治疗妇科炎症性疾病的中药复方,已被认定为国家中药保护品种和国家基本药物目录品种,并已载入《中华人民共和国药典》 2020年版,分为妇科千金片和妇科千金胶囊2个品种。妇科千金方由千斤拔、金樱根、穿心莲、功劳木、单面针、鸡血藤、党参和当归8味中药组成。通过梳理妇科千金方的化学成分、质量控制、药动学和药理作用等相关文献并结合实际研究,基于“中药质量标志物理论”进行预测分析,小檗碱、巴马汀、药根碱、新穿心莲内酯苷、穿心莲内酯、新穿心莲内酯苷元、7-O-甲基汉黄芩素、染料木苷、芒柄花苷、染料木素、柚皮素、反式阿魏酸、水杨酸和Z-藁本内酯等专属性高、可测性强,可作为妇科千金方的潜在质量标志物,为其质量控制研究提供参考。  相似文献   
104.
Two-level factorial and central composite experimental designs were used to study the influence of operating conditions (pressure and beam current as an example) on gas target design for the production of medical radionuclides. Other aspects of design primarily the foil were analyzed to determine the effect of material properties or the expected performance of the target window. The use of empirical models relating the target's performance to operating conditions provides an adequate method to quantify properties of interest. These models can be readily incorporated into a computer-controlled system capable of updating their parameters, and performing further experiments while ensuring routine production requirements are met. The krypton gas target for the production of 81Rb was utilized as an example although the models are applicable to gas targets, in general.  相似文献   
105.
吴秀稳  杨秀伟 《中草药》2020,51(13):3383-3392
目的研究羌活Notopterygium incisum的香豆素类成分及其抗炎活性。方法采用硅胶、HPLC等柱色谱方法进行分离纯化,通过质谱、核磁共振波谱数据鉴定化合物的结构;采用脂多糖(LPS)诱导的小鼠巨噬细胞RAW 264.7炎症反应模型,考察羌活中香豆素类成分对炎症反应模型一氧化氮(NO)生成的影响。结果从羌活甲醇提取物分离得到24个香豆素类化合物,分别鉴定为异欧前胡素(1)、川白芷素(2)、补骨脂素(3)、香柑内酯(4)、茵陈素(5)、欧芹酚(6)、5-去氢羌活醇(7)、环氧脱水羌活醇(8)、7″-O-甲基异羌活醇(9)、佛手柑素(10)、7-异戊烯氧基-6-甲氧基-香豆素(11)、栓翅芹烯醇(12)、羌活醇(13)、去甲呋喃羽叶芸香素(14)、异羌活醇(15)、蛇床夫内酯(16)、6-异戊烯氧基伞形花内酯(17)、紫花前胡苷元(18)、异虎耳草素(19)、紫花前胡苷(20)、前胡苷V(21)、前胡苷I(22)、印枳苷元-11-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖苷(23)、羌活苷(24)。化合物7~10、13和15抑制LPS诱导的RAW 264.7细胞NO生成活性最强,最大半数抑制浓度(IC_(50))值为8.50~35.12μmol/L。结论化合物7为新的天然产物,化合物17为首次从羌活中分离得到;C-5位上具有多烯烃结构的香豆素抑制LPS诱导的RAW 264.7细胞NO生成活性较强。  相似文献   
106.
Objectives: A rapid and sensitive gas chromatography–mass spectrometry (GC–MS) method for quantitative and qualitative analysis of essential oil from Curcuma wenyujin rhizomes was established. Methods: The essential oil of C. wenyujin rhizomes was extracted by supercritical CO2 extraction (SFE). Six main bioactive compounds (eucalyptol, β-elemene, curzerene, germacrone, curdione, and curcumol) were analyzed in selected ion monitoring mode (SIM). Results: Curzerene is not originally present in C. wenyujin rhizomes, but is a product of the transformation of furanodiene at high temperature. The six target components demonstrated good linearity (R2 > 0.9979) over a relatively wide concentration range. The interday and intraday variations had relative standard deviation values less than 5% and the average recovery ranged from 96.95% to 100.04%. The limit of quantitation ranged from 0.032 to 0.235 μg/mL. The developed method was successfully used to analyze the six compounds in 17 samples collected from different origins. Significant variation was observed for the concentrations of the six compounds. In addition, 51 constituents were identified in C. wenyujin rhizome essential oil, consisting of 87.66% of the total essential oil, including curdione, curzerene, dehydrocurdione, germacrone, 1,4-bis(2-benzimidazoyl)benzene, neocurdione, curcumenone, and β-elemene. Conclusions: The proposed method will be useful in the quality control of C. wenyujin rhizome essential oil production.  相似文献   
107.
BackgroundMinimally-invasive methods to treat scars address a common pathway of altering collagen structure, leading to collagen remodeling.ObjectiveIn this study, we employed in situ redox chemistry to create focal pH gradients in skin, altering dermal collagen, in a process we refer to as electrochemical therapy (ECT). The effects of ECT to induce biochemical and structural changes in ex vivo porcine skin were examined.MethodsDuring ECT, two platinum electrodes were inserted into fresh porcine skin, and following saline injection, an electrical potential was applied. pH mapping, high frequency ultrasonography, and two photon excitation microscopy and second harmonic generation (SHG) microscopy were used to evaluate treatment effects. Findings were correlated with histology.ResultsFollowing ECT, pH mapping depicted acid and base production at anode and cathode sites respectively, with increasing voltage and application time. Gas formation during ECT was observed with ultrasonography. Anode sites showed significant loss of SHG signal, while cathode sites showed disorganized collagen structure with fewer fibrils emitting an attainable signal. Histologically, collagen denaturation at both sites was confirmed.ConclusionWe demonstrated the production of in situ acid and base in skin occurring via ECT. The effects chemically and precisely alter collagen structure through denaturation, giving insight on the potential of ECT as a simple, low-cost, and minimally-invasive means to remodel skin and treat scars.  相似文献   
108.
The neuroinflammatory responses to human immunodeficiency virus type 1 (HIV-1) coat proteins, such as glycoprotein 120 (gp120), are considered to be responsible for the HIV-associated distal sensory neuropathy. Accumulating evidences suggest that T-cell line tropic X4 gp120 increases macrophage infiltration into the peripheral nerves, and thereby induces neuroinflammation leading to pain. However, the mechanisms underlying X4 gp120-induced macrophage recruitment to the peripheral nervous systems remain unclear. Here, we demonstrated that perineural application of X4 gp120 from HIV-1 strains IIIB and MN elicited mechanical hypersensitivity and spontaneous pain-like behaviors in mice. Furthermore, flow cytometry and immunohistochemical studies revealed increased infiltration of bone marrow-derived macrophages into the parenchyma of sciatic nerves and dorsal root ganglia (DRG) 7 days after gp120 IIIB or MN application. Chemical deletion of circulating macrophages using clodronate liposomes markedly suppressed gp120 IIIB-induced pain-like behaviors. In in vitro cell infiltration analysis, RAW 264.7 cell (a murine macrophage cell line) was chemoattracted to conditioned medium from gp120 IIIB- or MN-treated cultured Schwann cells, but not to conditioned medium from these gp120-treated DRG neurons, suggesting possible involvement of Schwann cell-derived soluble factors in macrophage infiltration. We identified using a gene expression array that CXCL1, a chemoattractant of macrophages and neutrophils, was increased in gp120 IIIB-treated cultured Schwann cells. Similar to gp120 IIIB or MN, perineural application of recombinant CXCL1 elicited pain-like behaviors accompanied by macrophage infiltration to the peripheral nerves. Furthermore, the repeated injection of CXCR2 (receptor for CXCL1) antagonist or CXCL1 neutralizing antibody prevented both pain-like behaviors and macrophage infiltration in gp120 IIIB-treated mice. Thus, the present study newly defines that Schwann cell-derived CXCL1, secreted in response to X4 gp120 exposure, is responsible for macrophage infiltration into peripheral nerves, and is thereby associated with pain-like behaviors in mice. We propose herein that communication between Schwann cells and macrophages may play a prominent role in the induction of X4 HIV-1-associated pain.  相似文献   
109.
This article reviews the nature of the functioning impairments that constitute schizophrenic disorder and provides specific guidelines for identifying these impairments in clinical evaluations. Attention is paid to certain distinctive profiles of impairment in adolescent as opposed to adult schizophrenics and to differential diagnosis between emerging schizophrenia and other conditions with which it may share some symptoms. Illustrations are provided of aspects of the interview behavior and clinical history of young people that provide clues to such characteristics of schizophrenia as disordered thinking, inaccurate perception of reality, interpersonal ineptness, and inadequate control over ideas, affects, and behavior.  相似文献   
110.
Polyethylene glycol (PEG)-coated (pegylated) gold nanoparticles (AuNPs) have been proposed as drug carriers and diagnostic contrast agents. However, the impact of particle characteristics on the biodistribution and pharmacokinetics of pegylated AuNPs is not clear. We investigated the effects of PEG molecular weight, type of anchoring ligand, and particle size on the assembly properties and colloidal stability of PEG-coated AuNPs. The pharmacokinetics and biodistribution of the most stable PEG-coated AuNPs in nude mice bearing subcutaneous A431 squamous tumors were further studied using 111In-labeled AuNPs. AuNPs coated with thioctic acid (TA)-anchored PEG exhibited higher colloidal stability in phosphate-buffered saline in the presence of dithiothreitol than did AuNPs coated with monothiol-anchored PEG. AuNPs coated with high-molecular-weight (5000 Da) PEG were more stable than AuNPs coated with low-molecular-weight (2000 Da) PEG. Of the 20-nm, 40-nm, and 80-nm AuNPs coated with TA-terminated PEG5000, the 20-nm AuNPs exhibited the lowest uptake by reticuloendothelial cells and the slowest clearance from the body. Moreover, the 20-nm AuNPs coated with TA-terminated PEG5000 showed significantly higher tumor uptake and extravasation from the tumor blood vessels than did the 40- and 80-nm AuNPs. Thus, 20-nm AuNPs coated with TA-terminated PEG5000 are promising potential drug delivery vehicles and diagnostic imaging agents.  相似文献   
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