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11.
目的以机油为分散剂高温热解人发后发现新型纳米碳点,通过动物实验评价了该碳点的生物效应。方法利用高温热解法对人发和机油进行炭化,对炭化产物进行萃取、过滤分离和透析得到一种具有水溶性的新型物质碳点,并命名为JYRF-CDs。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HR-TEM)、紫外-可见分光光谱、傅里叶变换红外光谱、荧光光谱、X射线光电子能谱分析(XPS)等多种方法对JYRF-CDs进行表征,利用小鼠单核巨噬细胞RAW264.7细胞进行CCK-8毒性实验来评价JYRF-CDs的安全性,并通过小鼠耳肿胀实验和小鼠醋酸扭体实验对JYRF-CDs的生物效应进行评价。结果 JYRF-CDs外形为类球形,粒径均匀分布在1.8~3.6 nm,晶格间距为0.219 7 nm。细胞毒性实验结果显示,JYRF-CDs具有低毒性,动物实验结果表明JYRF-CDs具有良好的抗炎和镇痛作用。结论首次以机油为分散剂高温热解人发后发现一种全新的碳点JYRF-CDs,以JYRF-CDs为突破口,更加明确阐释以机油为分散剂高温热解人发后炭化产物具有生物效应的物质基础,为纳米类成分的研究提供了一种新方法。  相似文献   
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Objective: Polygoni Multiflori Radix (PM) is a traditional herbal medicine with repeated reports of liver injury events in recent years. We wondered whether the classical processing method, namely, nine-time steaming and sun drying (NSSD), had toxicity-attenuating effects on PM and the relationships between toxicity and times of processing, as well as with the alteration trends of its compounds. Materials and Methods: The chemical fingerprints of different PM extracts were developed using ultra-high-performance liquid chromatography. The spectrum-toxicity correlation between the chemical fingerprints and hepatocellular toxicity was analyzed with multiple correlation analysis. Results: The results suggested that the hepatotoxicity of NSSD processing products markedly decreased with the repeated steaming and sun drying, which was obviously superior to the product processed by the modern method. Comprehensive analysis revealed that the contents of cis-stilbene glycoside and emodin-8-O-β-D-glucoside related to liver injury susceptibility were reduced with the times of NSSD processing, which was consistent with the decreased trend of hepatocellular toxicity. After the five times of NSSD, the contents of them as well as the hepatotoxicity of PM were steady. Moreover, we found that the contents of catechin and physcion declined rapidly after the one time of NSSD and then remained stable until the nine times of NSSD. Based on the fact, they could be utilized to indicate whether PM products were processed by steaming and sun drying. Conclusions: This paper confirmed that the NSSD had a good influence on the toxicity attenuating to PM and found four compounds which could apply for the quality control of PM.  相似文献   
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目的 研究伞骨草水提物的利尿和抗炎作用,以及利尿后对电解质平衡、糖代谢及肾脏功能的影响,并对伞骨草水提物安全性进行初步评价。方法 采用小鼠代谢笼法,检测盐水负荷小鼠在给药6 h后的排尿量,并分析小鼠尿液中离子浓度、血清中糖原、尿素氮和肌酐的变化;采用二甲苯致小鼠耳廓肿胀法,计算耳廓肿胀度及肿胀抑制率,角叉菜胶致大鼠足趾肿胀法,计算足趾肿胀率,小鼠急性毒性试验初步评价伞骨草水提物的安全性。结果 与对照组比较,伞骨草水提物能明显增加小鼠的排尿量,尿液中K+、Cl-的浓度明显增加,高剂量组Na+、Ca2+浓度明显增加;伞骨草对小鼠血清中的糖原、尿素氮和肌酐均无明显影响;伞骨草中、高剂量对二甲苯所致小鼠耳廓肿胀和角叉菜胶所致大鼠足趾肿胀具有明显的抑制作用;伞骨草水提物24 h内小鼠单次灌胃给药急性毒性试验的LD50为:12.33 g·kg-1(相当于生药82.15 g·kg-1),动物在4 h内出现毒性反应,主要表现为主要表现为腹泻、俯卧、竖毛、运动失调、死亡,腹泻至给药第2天恢复。结论 伞骨草水提物具有明显的利尿和抗炎作用,并且对机体的血糖水平和肾脏功能无明显影响。  相似文献   
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目的:探究海莲叶提取物对胃癌细胞增殖的抑制作用及对小鼠急性毒性实验。方法:先通过实验证实海莲叶提取物可对患者的胃癌细胞SGC-7091、MGC80-3可起到促进作用,应对实验小鼠皮下建立移植瘤模型,随后对小鼠注射海莲叶提取物,观察对胃癌细胞增殖的抑制情况,随后对药物的毒性进行分析。结果:给药组与溶媒对照组急性毒性反应相比显著较高,差异具有统计学意义(P<0.05)。结论:海莲叶提取物可对胃癌细胞增殖的抑制作用,并均已经在实验中得到了证实,海莲叶提取物可明显降低小鼠的急性毒性反应。  相似文献   
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BackgroundImproved survivorship in patients with breast cancer means many are currently living with the late effects of radiotherapy, particularly fibrosis. Personalized treatment is not currently considered for patients with breast cancer. Radiation-induced lymphocyte apoptosis (RILA), a predictive assay, could offer a novel approach in predicting patients at a higher risk of developing this late toxicity and therefore improving informed decision-making.Materials and MethodsA systematic search of PubMed and Embase was performed and eight clinical trials were identified that investigate RILA as a predictor of late breast fibrosis after radiotherapy.ResultsMedian RILA scores were lower in patients who experienced ≥ grade 2 fibrosis than in patients who experienced ≥ grade 1. A clear inverse relationship between RILA scores and late toxicity was reported in the literature; however, there were several other confounding factors involved in the development of fibrosis. CD8 lymphocytes were reported to have superior sensitivity and specificity over CD4 lymphocytes.ConclusionRILA was reported to be an effective biomarker in predicting fibrosis in breast cancer but other factors also need to be considered before clinical implementation.  相似文献   
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Introduction: Ocular dysfunctions and toxicities induced by antiepileptic drugs (AEDs) are rarely reviewed and not frequently received attention by treating physicians compared to other adverse effects (e.g. endocrinologic, cognitive and metabolic). However, some are frequent and progressive even in therapeutic concentrations or result in permanent blindness. Although some adverse effects are non-specific, others are related to the specific pharmacodynamics of the drug.

Areas covered: This review was written after detailed search in PubMed, EMBASE, ISI web, SciELO, Scopus, and Cochrane Central Register databases (from 1970 to 2019). It summarized the reported ophthalmologic adverse effects of the currently available AEDs; their risks and possible pathogenic mechanisms. They include ocular motility dysfunctions, retinopathy, maculopathy, glaucoma, myopia, optic neuropathy, and impaired retinal vascular autoregulation. In general, ophthalmo-neuro- or retino-toxic adverse effects of AEDs are classified as type A (dose-dependent), type B (host-dependent or idiosyncratic) or type C which is due to the cumulative effect from long-term use.

Expert opinion: Ocular adverse effects of AEDs are rarely reviewed although some are frequent or may result in permanent blindness. Increasing knowledge of their incidence and improving understanding of their risks and pathogenic mechanisms are crucial for monitoring, prevention, and management of patients’ at risk.  相似文献   

19.
目的 探讨局部晚期鼻咽癌洛铂单药单周方案同期放疗中洛铂最大耐受剂量(MTD)。方法 选择18例Ⅲ-ⅣA期鼻咽癌初治患者,采用根治性IMRT同时进行洛铂剂量递增试验。洛铂初始剂量10 mg/m2,组间递增剂量为5 mg/m2,每个剂量组至少3位受试者。如无剂量限制性毒性反应则进入下一剂量组直至MTD,定期评价疗效及不良反应。结果 10、15 mg/m2剂量组各3例,20、25 mg/m2剂量组6例。25mg/m2组出现2例剂量限制性毒性反应,因此MTD确定为20 mg/m2。患者治疗结束后3个月,鼻咽部肿瘤和颈部阳性淋巴结临床缓解率为100%。主要毒性反应为骨髓抑制。结论 洛铂单药周方案同期放化疗治疗局部晚期鼻咽癌的MTD为20mg/m2,该方案疗效可靠安全性较好,值得开展进一步临床研究。  相似文献   
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BackgroundMidostaurin, a multikinase inhibitor, is approved for treatment of FLT3-mutant acute myeloid leukemia (AML). A phase I study established that midostaurin 75 mg orally twice daily for 14 days with standard dose azacitidine was safe and tolerable in elderly patients with AML. Herein, we report the phase II expansion cohort of previously untreated elderly or unfit patients with AML.Patients and MethodsPrimary objectives were to further describe the toxicity profile and determine the response rate in untreated patients with AML. Patients received midostaurin 75 mg orally twice daily on days 8 to 21 in combination with intravenous azacitidine at 75 mg/m2 on days 1 to 7. Plasma inhibitory activity assay for FLT3 was performed pretreatment and on day 8 and day 15 of each cycle.ResultsTwenty-six patients (median age, 74 years; range, 59-85 years) with FLT3 wild-type AML were accrued. Patients received a median of 2 cycles of therapy (range, 1-10 cycles). Seven (29%) of 24 evaluable patients achieved a clinical response (4 complete response; 1 complete response with incomplete count recovery; and 2 partial response). The median overall survival was 244 days (95% confidence interval, 203-467 days). Hematologic, infectious, and gastrointestinal toxicities were comparable to similar studies. Peripheral blood FLT3 wild-type phosphorylation declined to 8% to 55% of pretreatment by day 15 of cycle 1 (7 patients) and declined with subsequent cycles (< 10% baseline) in 2 patients who were analyzed after cycle 3.ConclusionMultiple cycles of azacitidine and midostaurin were not well-tolerated, but persistent inhibition of FLT3 wild-type phosphorylation suggest intermittent dosing of midostaurin should be considered in future low-intensity regimens for FLT3-mutant AML.  相似文献   
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