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51.
目的探讨多剂量地塞米松和盐酸氨溴索对孕鼠和胎鼠的不良影响。方法选择18只妊娠16d SD孕鼠,随机分为生理盐水对照组、地塞米松组和盐酸氨溴索组3组,每组6只。于孕16、17、18 d尾静脉分别注射生理盐水2 m l/d、地塞米松0.8 m g.kg-1.d-1和盐酸氨溴索75 m g.kg-1.d-1,于孕第19天时剖宫取胎。观察孕鼠体重、胎鼠肝脏、肾脏及肾上腺结构,比较多剂量地塞米松和盐酸氨溴索对孕鼠和胎鼠的不良影响。结果多剂量地塞米松组孕鼠体重呈下降趋势,3组孕鼠体重于用药前(妊娠16 d)和用药后第1天各组体重差异无统计学意义(P>0.05);用药后第2天和第3天,地塞米松组孕鼠体重明显低于对照组和盐酸氨溴索组,差异有统计学意义(P<0.05);多剂量地塞米松组12只胎鼠中有5只的肝脏呈不同程度的坏死,盐酸氨溴索组和对照组肝脏结构未见异常。结论产前应用多剂量地塞米松对孕鼠和胎鼠均有不同程度的副作用,而大剂量盐酸氨溴索未见明显的不良影响。 相似文献
52.
目的为探讨地塞米松(DXM)对实验性自身免疫性脑脊髓炎(EAE)大鼠临床指标和单核细胞趋化蛋白1(MCP1)mRNA的影响。方法将正常大鼠、完全抗原和百日咳毒素原液免疫后的大鼠免疫后7d,分成:正常大鼠、EAE组和DXM组。DXM组给予DXM腹腔注射,另外两组给予生理盐水注射。取脑和脊髓制成石蜡切片,进行苏木素伊红(HE)染色和MCP1mRNA的原位杂交(ISH),并比较各项临床指标。结果DXM组的发病率、临床评分和MCP1mRNA的阳性细胞数显著性降低(P<0.01)。结论进一步证实DXM的使用可对EAE有治疗作用。 相似文献
53.
目的:建立豚鼠外耳淋巴液中磷酸地塞米松的含量测定方法.方法:采用浸满磷酸地塞米松溶液的明胶海绵颗粒置于圆窗龛内,采集给药1 h后鼓阶外淋巴液.HPLC色谱条件为,ZORBAX Eclipse XDB-C18色谱柱(4.6 mm×250 mm,5μm),流动相为7.56 mmol·L-1硫酸铵-乙腈(70:30),流速1.0ml·min-1,柱温20℃,紫外检测波长239 nm.结果:磷酸地塞米松的线性范围为0.10~4.8 mg·L-1(r=0.999 8).最低检测限为6.25μg·L-1,日内和日间RSD分别为1.7%和2.3%.给药1h后鼓阶外淋巴液中磷酸地塞米松的浓度为2.12 mg·L-1.结论:该法灵敏度高,准确性、重复性好,可用于外淋巴液中磷酸地塞米松的测定. 相似文献
54.
目的:建立醋酸地塞米松静注乳剂的含量测定方法.方法:采用C18色谱柱(4.60cm×25cm,10μm),流动相为水(含0.164mol/L磷酸,用三乙胺调pH值至3.5)-乙腈(43:57),以甲磺酸酚妥拉明为内标.结果:醋酸地塞米松量在1.84μg/mL~46.0μg/mL时,与峰面积比值呈良好线性,回归方程为A e=0.0868C 0.00885(r=0.9999,n=6),方法的日内与日间精密度RSD均小于2%,回收率分别为100.1%,98.7%和99.8%.结论:该方法快速准确、精密,可以用于该制剂的含量测定及稳定性分析. 相似文献
55.
56.
H. EROG LU H. S. KASe L. ONER Oe . F. TUe RKOG LU N. AKALAN M. F. SARGON N. Oe ZER 《Journal of microencapsulation》2013,30(5):603-612
Dexamethasone sodium phosphate (DSP) is a widely used corticosteroid in the treatment of brain oedema associated with brain tumours. DSP has many side effects that limit its usage at an effective concentration. The objective of this study was to minimize these side effects by encapsulating DSP using biodegradable synthetic polymers, to extend the release time from microspheres and to evaluate the effectiveness in the treatment of brain oedema. Microspheres containing 5% DSP were formulated by the solvent evaporation method by using a 1:1 mixture of two synthetic polymers, poly(lactic-co-glycolic acid) and L-polylactic acid (PLGA and L-PLA). The surface morphologies and particle size distribution of the microspheres were investigated. The in-vitro 相似文献
57.
目的 评价地塞米松对老龄大鼠术后认知功能的影响.方法 雄性SD大鼠180只,18 ~ 20月龄,体重400 ~ 600 g,采用随机数字表法,将大鼠随机分为3组(n=60)∶对照组(C组)、手术组(S组)和地塞米松组(D组).采用大鼠剖腹探查手术模型.D组于麻醉开始时腹腔注射地塞米松10 mg/kg.C组不进行手术,腹腔注射生理盐水2 ml/kg.于术后3h、7d时测定海马OX42(小胶质细胞激活特异性标志物)的表达水平;于术后3h、1d、3d和7d时测定海马IL-1β mRNA和TNF-α mRNA的表达水平.采用Morris水迷宫实验和条件恐怖适应实验检测大鼠术后认知功能.结果 与C组比较,S组和D组逃逸潜伏期延长,穿越原平台次数减少,术后僵直时间缩短,海马OX42表达、IL-1β mR-NA和TNF-α mRNA表达上调(P<0.05或0.01);与S组比较,D组逃逸潜伏期缩短,穿越原平台次数增多,术后僵直时间延长,海马OX42、IL-1β mRNA和TNF-α mRNA表达下调(P<0.05或0.01).结论 地塞米松可抑制海马小胶质细胞过度激活,减轻炎性反应,从而改善老龄大鼠术后认知功能. 相似文献
58.
《Cochlear implants international》2013,14(5):254-263
AbstractObjectivesCochlear implantation can result in trauma leading to increased tissue response and loss of residual hearing. A single intratympanic application of the corticosteroid dexamethasone is sometimes used clinically during surgery to combat the potential effect of trauma on residual hearing. This project looked at the safety and efficacy of dexamethasone eluted from an intracochlear array in vivo.MethodsThree trials were conducted using normal hearing adult guinea pigs implanted with successive iterations of dexamethasone-eluting (DX1, DX2, and DX3) or non-eluting (control) intracochlear electrode arrays. The experimental period for each animal was 90 days during which hearing tests were performed at multiple time points.ResultsThere was no significant difference between matched control array and dexamethasone array groups in terms of spiral ganglion neuron density, organ of Corti condition, or fibrosis and ossification. A cochleostomy seal was present in all implanted cochleae. There were no differences in the degree of hearing threshold shifts between DX1 and DX3 and their respective control arrays. Cochleae implanted with DX2 arrays showed less hearing loss and marginally better spiral ganglion neuron survival than their control array counterparts. Post-explant inspection of the DX2 and DX3 arrays revealed a difference in pore density following dexamethasone elution.ConclusionThe dexamethasone doses used were safe in the guinea pig cochlea. Dexamethasone did not inhibit formation of a cochleostomy seal. The level of hearing protection afforded by dexamethasone eluting from an intracochlear array may depend upon the degree of elution and level of trauma inflicted. 相似文献
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60.
Cytotoxic chemotherapy can induce a systemic inflammatory response which has been proposed to be an underlying mechanism of cancer treatment related fatigue. Dexamethasone, a synthetic glucocorticoid that has potent anti-inflammatory effects, is incorporated into chemotherapy regimens to prevent chemotherapy-induced nausea and vomiting (CINV). The purpose of this study was to determine whether by suppressing cytotoxic chemotherapy-induced inflammation, dexamethasone could ameliorate chemotherapy induced fatigue/lethargy in tumor free mice. The effect of dexamethasone (DEX) on Cytoxan-Adriamycin (CA)-induced inflammation was assessed by measuring circulating levels of IL-1β, TNF-α, IL-6, GCSF, KC, and MCP-1 twenty-four-hours post CA injection. Decline in voluntary wheel running activity (VWRA) from baseline (used as a proxy for fatigue/lethargy), body weight and composition, and food intake were monitored in mice administered four cycles of CA every two weeks with or without DEX. CA increased circulating levels of IL-6, GCSF, KC, and MCP-1 and caused a rapid decline in VWRA and body weight immediately following CA-injection. Although the acute CA-induced decline in VWRA and body weight was not evident in mice administered CA + DEX, DEX alone had a suppressive effect on VWRA, and body weight continued to decline in mice administered both CA and DEX while it returned to baseline in CA-treated mice. CA or DEX alone had no long term impact on VWRA but DEX exacerbated lethargy and weight loss in CA-treated mice. Despite dampening the systemic inflammatory response to chemotherapy, dexamethasone failed to ameliorate acute or long term chemotherapy related fatigue/lethargy. Our pre-clinical findings suggest that supportive therapies like dexamethasone used to acutely control nausea and vomiting in cancer patients may actually contribute to overall symptom burden in cancer patients. 相似文献