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61.
??Abstract?? Objective To discuss the changes of S100B protein and GFAP levels and its relationship with 1 min Apgar scoring in the serum of neonates born to mothers with preeclampsia of different degrees. Methods From Oct.2012 to Mar.2013 in Chilren’s hospital of Shanxi province ?? 40 cases of newborns born to mothers with preeclampsia were divided into two groups: mild preeclampsia group ??L group 20 cases????severe preeclampsia group ??H group 20 cases????a healthy control group was established ??N group 20 cases????newborns of three groups were taken specimen at the time of admission ?? dual- antibody sandwich enzyme-linked immunosorbent assay ??ELISA?? was used to detect the level of serum GFAP and S100B . In the first three days after admission cranial ultrasound was performed in each child. Results The difference among the L??H and N group was statistically significant ??P2=17.20??P??0.05??; S100B and GFAP levels in L and H group were positively correlated ??γ= 0.658?? P??0.05??; S100B?? GFAP levels in L and H group and neonatal 1min Apgar score were negatively correlated ??γ$subScript$S100B$/subScript$=-0.482??γ$subScript$GFAP$/subScript$=-0.534??P??0.01??. Conclusion The more serious eclampsia?? the greater the possibility of brain damage?? and the more serious the elevation of S100B and GFAP levels?? and was negatively correlated with 1 min Apgar score?? which indicates that the possibility of S100B protein and GFAP as a predictor of neonatal brain injury deserves further study.  相似文献   
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63.
At 4 h after injection of carrageenan into the gingiva, the 12-lipoxygenase activity of the gingival homogenate was markedly increased. Activity in the cytosol and microsomal fractions was markedly increased when assessed as the specific activity based on nmol/min/mg of protein, and in the cytosol fraction as the percentage distribution of total activity. The 12-lipoxygenase activity in the homogenate from carrageenan-treated gingiva was not affected by either EDTA or calcium ion, or a combination of the two. 12-lipoxygenase activity in both carrageenan-treated and untreated gingiva was inhibited dose-dependently by AA861, a striking difference from its effect on platelet 12-lipoxygenase. There was a marked increase of 12-lipoxygenase activity in experimentally inflamed gingiva compared to the non-inflamed gingiva.  相似文献   
64.
The effects of chlorpromazine (CPZ) on tooth mineralization were examined using incisor dentine in adult rats and cultured tooth germs of mandibular first molars dissected from mouse embryos. CPZ (10, 50 and 250 mg/kg, s.c.) substantially inhibited dentine mineralization as evaluated by contact microradiographs. Plasma calcium and phosphorus concentrations were not decreased by CPZ (10 and 50 mg/kg). Physicochemical effects were not involved in the action of CPZ on the mineralization. In vitro experiments showed that CPZ (1 and 10 μM) inhibited mineralization and alkaline phosphatase (ALP) activity in the tooth germs. As CPZ has the properties of a calmodulin antagonist, the calmodulin antagonists W-7 and W-5 were also examined. Both inhibited mineralization and ALP activity in tooth germs; W-5 had less effect than W-7. These in vivo and in vitro findings suggest that CPZ inhibited cell-mediated mineralization in dentine without affecting the calciumdashregulating system and physicochemical mineral deposition. In addition, calmodulin could be involved in cell-mediated mineralization.  相似文献   
65.
Adult male Syrian hamsters were treated by swabbing the apex of the buccal pouch with corn oil (control, C), 1 mM benzo(a)pyrene (BP), nicotine (NC), or BP + NC in corn oil, twice daily, 5 days a week. After a 4-week treatment, the pouches and submandibular glands were dissected and used for the determination of endogenous prostaglandin (PG) production and studies on in vitro PG synthesis. Of the three PGs analysed (PGE2, PGF2 and 6-keto-PGF1), PGE2 was predominant in the pouch and the glands. BP or NC alone had only a weak effect on PG synthesis in both tissues. However, the combination of BP and NC had a synergistic effect, causing diminished PG synthesis in both tissues. In buccal pouch, BP + NC significantly decreased the concentrations of endogenous PGE2 and PGF2 (PGE2: 0.669 + 0.254 versus 1.698 + 0.460, PGF2: 0.273 ± 0.090 versus 0.625 ± 0.272 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). Similarly significant results were also found for in vitro PG synthesis (PGE2: 0.541 ± 0.249 versus 1.399 ± 0.340, PGF2: 1.045 ± 0.428 versus 2.133 ± 0.510 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). In submandibular glands, BP + NC significantly diminished the concentration of endogenous PGE2 (1.183 ± 0.175 versus 2.379 ± 0.488 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). The synthesis of 6-keto-PGF1 in both tissues, and the synthesis of PGF2 in submandibular gland, were slightly decreased with all treatments.  相似文献   
66.
Pulp fibroblasts were isolated from human deciduous and supernumerary teeth and cultured in vitro. With continued culture in normal tissue-culture medium, six pulp fibroblast strains formed cell nodules after 10–15 days. By electron microscopy the nodules had matrix vesicles, and needle-shaped crystals associated with a dense network of collagen fibrils. The crystalline material exhibited a pattern consistent with hydroxyapatite when nodules were examined by X-ray diffractometry. Furthermore, the cells showed high levels of alkaline phosphatase activity, which could be increased more than seven-fold by the addition of 1,25(OH)2D3 (5 × 10−9−5 × 10−8M). In addition to the production of type I collagen, these cells also synthesized fibronectin and osteonectin. The formation of mineralized tissue nodules by pulp cells in vitro provides a useful system for study of the pathological calcification of pulp tissues.  相似文献   
67.
Tenascin is a large extracellular-matrix glycoprotein found in developing connective tissue. A cDNA probe to mouse tenascin, mTN2, was used to determine the cellular origins of this molecule in the murine tooth germ by in situ hybridization. At embryonic day 19, a hybridization signal significantly greater than background was detected with mTN2 in the subodontoblastic layer of the dental mesenchyme and in the inner enamel epithelium of the enamel organ. At postnatal day 1, a signal was detected over pre-odontoblasts and the strata intermedium and externum. No tenascin mRNA was detected in odontoblasts or the stellate reticulum at either age, and hybridization in ameloblasts was not significantly greater than background at postnatal day 1. Thus, much of the tenascin found throughout developing teeth appears to be synthesized by pre-odontoblasts and the inner enamel epithelium, the two populations of cells destined to generate mineralized matrix.  相似文献   
68.
The β1-integrins (VLA family) are cellular adhesion molecules (CAM) that play a major role in cell-cell and cell-matrix interactions. The expression pattern of CAM was studied in 5 clinically normal volunteers with healthy gingiva and in 18 patients with clinically different stages of periodontitis. In healthy human gingiva α2. α3 and α6 integrin chains were found in a characteristic distribution, showing a broad continuous expression on the junctional and sulcular epithelium sites. The expression of these integrins was demonstrated primarily on the basal cell layers and in some cells of the stratum spinosum. Inflammatory stages of periodontitis revealed further upregulation of α2, α3 and α6 integrins into the junctional and sulcular epithelial cells, which correlated with the stage of the periodontitis and the extent of the cellular infiltration. α4 and α6 were found to be the predominant β1 integrin chains on inflammatory cells. The amount of δ4 and ş6 positive infiltrative cells increased with the number of inflammatory cells. VCAM-1. the corresponding cell-cell ligand of VLA-4 (α4) was present on the majority of subepithelial vessels in all stages of gingivitis and periodontitis. The α5 subunit was expressed on both endothelium and gingival connective tissue cells. Samples from advanced periodontitis cases showed a higher number of a5 positive mononuclear cells. In comparison to normal epidermis, a human gingival epithelial cells express higher levels of integrins. This expression is further upregulated in advanced stages of periodontitis, indicating changes of the β1 integrin organization.  相似文献   
69.
目的 构建一套预防医学本科毕业生应对突发生物性公共卫生事件核心能力评价指标体系。方法 采用深入访谈和小组讨论等研究方法确定核心能力结构,并运用德尔菲法进行2轮专家咨询。以21位专家对该体系的咨询结果为依据,最终确定指标体系及其权重。采用Excel和SPSS 21.0软件进行数据整理和统计分析。结果 专家咨询的积极系数大于80%,权威系数大于0.7,均值为0.906。最终确定的指标体系由4个一级指标、10个二级指标、39个三级指标构成。结论 该评价指标体系可为探索提高毕业生核心能力的有效途径提供参考依据。  相似文献   
70.
摘要:目的 探讨液体负平衡对感染性休克患者急性生理学与慢性健康状态(APACHEII)评分的影响分析。方法 选取2018年1月~2020年1月本院收治的92例感染性休克患者,按不同液体管理模式分为常规组(采用液体平衡)和研究组(采用液体负平衡管理模式)各46例。对比分析2组患者心肺功能及APACHEII评分以及不良反应。结果 管理前2组患者全心舒张末期容量指数(GED-CVI)和血管外肺水指数(EVLWI)比较无统计学差异(P>0.05),管理后2组GED-CVI、EVLWI水平均增加(P<0.05),研究组上述水平高于常规组(P<0.05);研究组和常规组均完成了管理计划,2组管理前APACHEII评分比较,差异均无统计学意义(P>0.05),管理后均低于管理前(P<0.05),管理后研究组低于常规组(P<0.05);2组患者均未见明显不良反应发生。结论 液体负平衡应用于感染性休克患者,可改善心肺功能指标,降低患者APACHEII评分,可作为临床管理及防控的参考指标。  相似文献   
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