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101.
目的观察映山红花总黄酮(TFR)对盐酸异丙肾上腺素诱导的实验性心肌缺血的保护作用。方法采用皮下(sc)注射盐酸异丙肾上腺素(Iso)(8 mg·kg-1×2 d)诱导大鼠实验性心肌缺血模型,测定血清中MDA含量、GSH-PX活力、SOD及心肌组织中ATPase活性。同时行心肌组织病理组织学检查。结果TFR 30 mg·kg-1显著降低血清中MDA的生成,30,15 mg·kg-1及60,30 mg·kg-1升高SOD,GSH-PX的活力,60,30 mg·kg-1TFR可抑制心肌组织中Na+-K+-ATPase,Ca2+-Mg2+-AT-Pase,总ATPase活力的降低,TFR 60,30 mg·kg-1能显著改善sc Iso后心肌病理损伤程度,降低其病理损伤评分。结论TFR对盐酸异丙肾上腺素诱导的实验性心肌缺血有保护作用,其机制可能与减少体内自由基生成、改善心肌能量代谢有关。 相似文献
102.
目的在体外实验条件下,观察糖皮质激素是否促进β-淀粉样蛋白的神经元毒性作用。方法通过LDH释放率法检测细胞活力、TUNEL法测细胞凋亡以及LSCM测胞内Ca2+浓度的变化。结果单独的地塞米松(10-8,10-7,10-6mol·L-1)组或Aβ25-35(0.5μmol·L-1)组分别作用海马神经元后,细胞活力变化不明显(P>0.05);但与同剂量的DEX、Aβ25-35组相比,DEX+Aβ25-35组的细胞活力明显降低(P<0.05),同时胞内Ca2+显著上升(P<0.05),神经元的凋亡率增加明显,细胞内出现凋亡的典型形态学特征。结论糖皮质激素可能通过促进Aβ引起海马神经元胞内Ca2+升高增加神经元毒性作用。 相似文献
103.
目的建立HPLC同时测定人尿草酸和枸橼酸含量的方法。方法采用Agilent SB C18(250mm×4.6mm,5μm)色谱柱;Agilent zorbax extend-C18(4.6mm×12.5mm,5μm)为保护柱;以0.018mol.L-1磷酸二氢钾(含0.010mol.L-1四丁基硫酸氢铵和2.69×10-5mol/L EDTA,pH2.4~2.5)为流动相;检测波长210nm;流速1.5mL.m in-1;柱温25℃;进样量20μL;以50mg/mL磺基水杨酸沉淀尿蛋白。结果草酸最低检测限为0.4μg.mL-1。线性范围为1.563~100μg.mL-1,平均回收率为97.66%,日内及日间精密度RSD<13.50%。枸橼酸最低检测限为0.8μg.mL-1。线性范围为3.125~200μg.mL-1,平均回收率为97.71%,日内及日间精密度RSD<8.25%。结论该方法简便,灵敏度高,重复性好,可用于尿路草酸钙结石成因的研究。 相似文献
104.
2型糖尿病大鼠心肌间质胶原代谢的变化及罗格列酮的干预研究 总被引:2,自引:0,他引:2
目的观察糖尿病(DM)大鼠心肌间质胶原含量的变化及心肌组织基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、组织抑制物-1(TIMP-1)的表达变化及罗格列酮(RSG)对上述指标的影响。方法高脂高糖饮食加小剂量链尿佐菌素腹腔注射制备2型DM大鼠模型,将大鼠分为12周对照组和DM组,24周对照组、DM组和RSG组,分别检测各组大鼠心肌组织胶原含量、MMP-2,MMP-9,TIMP-1 mRNA表达变化及MMP-2,MMP-9,TIMP-1蛋白水平的变化。结果DM大鼠心肌间质胶原含量明显增加,MMP-2的表达明显减低,MMP-9,TIMP-1的表达均明显增加,但MMP-9/TIMP-1的比值下降。RSG治疗组胶原含量明显减少,MMP-2表达明显上调,MMP-9下调,TIMP-1明显下调,MMP-9/TIMP-1增加。结论MMP-2,MMP-9及其组织抑制物-1的调节失衡参与了DM心肌间质纤维化的发生与发展,RSG治疗可以通过调节基质金属蛋白酶-2、9及其组织抑制物-1的表达变化,抑制心肌纤维化,减轻心肌损伤。 相似文献
105.
目的对从白及块茎中提取多糖的工艺进行改进,为白及多糖的开发提供理论依据。方法采用煎煮前浸泡24 h及加入一定量ZTC1 1(Ⅱ)型天然澄清剂等新工艺,运用苯酚-硫酸法测定多糖含量及转移率。结果在提取液中,加入澄清剂4%的B组分、2%的A组分,且B∶A=2∶1,共澄清4 h,白及多糖含量及转移率均明显提高,且提取效果最好。结论白及多糖提取新工艺值得推广。 相似文献
106.
目的评价丙泊酚靶控输注在儿童鼻内镜手术中对血压、心率、术野出血及术后苏醒过程的影响。方法86例因腺样体肥大拟行手术患儿,ASA为Ⅰ-Ⅱ级,随机分成二组,每组43例,B组行丙泊酚靶控输注麻醉,I组行异氟醚吸入麻醉。分别观察手术开始后10,25,45 m in血压、心率变化及术野质量评分,记录术毕患儿自主呼吸恢复时间、睁眼时间、拔管时间,观察术后恶心、呕吐、躁动的发生率。结果①两组收缩压、舒张压和术野质量评分无显著差异;②B组患儿术后自主呼吸恢复时间、睁眼时间、拔管时间显著短于I组;③I组并发症高于B组。结论丙泊酚靶控输注用于儿童鼻内镜手术,血压、心率、术野质量评分佳,术毕麻醉恢复更为迅速、优良。 相似文献
107.
Grüb M Mielke J Rohrbach JM Schlote T 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(5):353-357
BACKGROUND: Trabecular aspiration has been discussed during the past few years as a new surgical method in the treatment of pseudoexfoliative glaucoma. In this procedure PEX-material, pigment and detritus are aspirated from the trabecular meshwork. Trabecular aspiration has been evaluated mainly in combination with cataract extraction. This study reports on our first experiences concerning the IOP-reducing effect of trabecular aspiration as a primary surgical method in the management of pseudoexfoliative glaucoma. MATERIALS: 17 eyes of 14 patients (7 m, 7 f; 12 OD, 5 OS; age 71 +/- 6 years) with pseudoexfoliative glaucoma were included in this study and operated on by standardised trabecular aspiration (vacuum max. 200 mm Hg, 180 - 270 degrees, 5 min). Therapy success was defined as an IOP reduction by more than 20 % and less than 21 mm Hg. RESULTS: Therapy success was 82 % (14 out of 17) on the first postoperative day, 50 % after 30 days (8 out of 16) and 23 % after 180 days (3 out of 13). IOP was 26.8 +/- 8.5 mm Hg before surgical intervention, 18.1 +/- 11.4 mm Hg after 1 day, 19.1 +/- 7.9 mm Hg after 30 days and 19.2 +/- 5.2 mm Hg after 180 days. Mean quantity of antiglaucomatous eye drops application was 3.1 +/- 0.9 preoperatively, 0.9 +/- 1.6 after 1 day, 0.8 +/- 1.2 after 30 days and 1.0 +/- 1.3 after 180 days. CONCLUSIONS: Trabecular aspiration achieves a good short-term effect in the reduction of IOP in patients with pseudoexfoliative glaucoma. However, this effect was limited to a few weeks in most patients. Trabecular aspiration as a primary surgical method in the management of pseudoexfoliative glaucoma does not appear to be suitable for long-term IOP reduction. 相似文献
108.
Role of taurine accumulation in keratinocyte hydration 总被引:2,自引:0,他引:2
Janeke G Siefken W Carstensen S Springmann G Bleck O Steinhart H Höger P Wittern KP Wenck H Stäb F Sauermann G Schreiner V Doering T 《The Journal of investigative dermatology》2003,121(2):354-361
Epidermal keratinocytes are exposed to a low water concentration at the stratum corneum-stratum granulosum interface. When epithelial tissues are osmotically perturbed, cellular protection and cell volume regulation is mediated by accumulation of organic osmolytes such as taurine. Previous studies reported the presence of taurine in the epidermis of several animal species. Therefore, we analyzed human skin for the presence of the taurine transporter (TAUT) and studied the accumulation of taurine as one potential mechanism protecting epidermal keratinocytes from dehydration. According to our results, TAUT is expressed as a 69 kDa protein in human epidermis but not in the dermis. For the epidermis a gradient was evident with maximal levels of TAUT in the outermost granular keratinocyte layer and lower levels in the stratum spinosum. No TAUT was found in the basal layer or in the stratum corneum. Keratinocyte accumulation of taurine was induced by experimental induction of skin dryness via application of silica gel to human skin. Cultured human keratinocytes accumulated taurine in a concentration- and osmolarity-dependent manner. TAUT mRNA levels were increased after exposure of human keratinocytes to hyperosmotic culture medium, indicating osmosensitive TAUT mRNA expression as part of the adaptation of keratinocytes to hyperosmotic stress. Keratinocyte uptake of taurine was inhibited by beta-alanine but not by other osmolytes such as betaine, inositol, or sorbitol. Accumulation of taurine protected cultured human keratinocytes from both osmotically induced and ultraviolet-induced apoptosis. Our data indicate that taurine is an important epidermal osmolyte required to maintain keratinocyte hydration in a dry environment. 相似文献
109.
Dakak M Genç O Gürkök S Gözübüyük A Balkanli K 《Journal of the Royal College of Surgeons of Edinburgh》2002,47(5):689-692
OBJECTIVE: Hydatidosis in man is frequently encountered in sheep and cattle raising regions of the world. We reviewed 422 patients, treated surgically for pulmonary hydatid disease in our clinic between January 1980 and January 1998, assessing the clinical features and results of results of operative treatment management in our centre. PATIENTS AND METHODS: 52 of the patients were female and 370 were male. The median age of the patients was 33 years (range, 11 to 66 years). The cysts were located in the right lung in 214 (50.7%) patients, the left lung in 156 (37%) and bilaterally in 17 (4%) cases. We found an intrathoracic extrapulmonary cyst in 35 (8.3%) patients. We performed enucleation and capitonnage in 202 cases, wedge resection in 40, cystotomy and capitonnage in 171, and lobectomy in 9 patients. The high-risk patients were treated with Albendazol (10 mg/kg/day), for a period of 3 months postoperatively. RESULTS: Preoperative diagnosis was based primarily on chest roentgenograms and led to correct diagnosis in 347 cases (82.2%). An additional computerised tomography (CT) scan in 56 cases and magnetic resonavive imaging (MRI) were required in 15 cases. The diagnosis is established intraoperatively in 4 cases. Most (296) patients presented with a solitary lung cyst. The rest were found to have multiple cysts in one or more lobes. 87 of 422 also had cysts in the liver, 19 in the spleen, and 1 in the pancreas. The follow-up data was completed in 392 of 422 (92.8%) patients. The mean follow-up period was 4.3 years (2 to 19 years). We detected recurrence in 3 patients (0.71%). CONCLUSION: The effective treatment of hydatid cyst(s) in the lung is complete excision of the cyst(s) with maximum preservation of the lung parenchyma. Additional medical treatment with Albendazole should be carried out for high-risk group patients. 相似文献
110.