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李聪  黄诗雨  陈丽华  刘红宁  高玲  管咏梅  吴璐 《中草药》2020,51(20):5395-5404
中药挥发油质量的稳定性是其发挥临床疗效及确保安全性的重要前提。由于中药挥发油的质量受到入药部位、药材产地、药材采收期、提取工艺、炮制工艺等诸多因素的影响,从而导致挥发油的出油率或所含化学成分出现差异,影响中药挥发油质量的均一性,进而影响挥发油的疗效。因此,如何把控挥发油的质量是中药挥发油发挥作用的关键。分析了药材不同入药部位、不同产地和不同采收期对中药挥发油质量的影响,并对《中国药典》2015年版含有挥发油成分的196味中药按药用部位进行分类,讨论了不同入药部位、产地和采收期对中药挥发油成分的差异性,以期为中药挥发油的开发及中药挥发油质量标准的建立提供参考。  相似文献   
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目的 探讨耳再造术中自体肋软骨切取手术的设计原则及操作要点.方法 回顾总结自2013年3月至2014年2月,403例耳再造术中自体肋软骨切取手术的设计方案及操作过程,强调对目标肋软骨的触诊,以确定手术切口位置;合理设计切口位置,采用合适的手术器械使切口最小化;根据整体手术流程,决定肋软骨切取次序,避免成为影响手术进度的瓶颈环节;防止切口周缘的过度损伤,对创缘进行适当处理后,采用美容缝合技术关闭伤口.结果 最小化手术切口的同时,采用美容缝合技术处理伤口,所有患者均恢复良好,切口Ⅰ期愈合,患者对胸部小切口满意.合理的切取顺序加快了整体手术进度,从而缩短了手术时间.结论 结合手术需求,准确定位目标肋软骨位置,合理设计并采用合适的手术器械,是手术切口最小化的重要条件;合理的切取次序能够优化手术流程,有助于缩短手术时间.  相似文献   
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Objectives To describe a technique for harvesting larger temporal bone specimens from human cadavers for the training of otolaryngology residents and fellows on the various approaches to the lateral and posterolateral skull base. Design Human cadaveric anatomical study. The calvarium was excised 6 cm above the superior aspect of the ear canal. The brain and cerebellum were carefully removed, and the cranial nerves were cut sharply. Two bony cuts were performed, one in the midsagittal plane and the other in the coronal plane at the level of the optic foramen. Setting Medical school anatomy laboratory. Participants Human cadavers. Main Outcome Measures Anatomical contents of specimens and technical effort required. Results Larger temporal bone specimens containing portions of the parietal, occipital, and sphenoidal bones were consistently obtained using this technique of two bone cuts. All specimens were inspected and contained pertinent surface and skull base landmarks. Conclusions The skull base block method allows for larger temporal bone specimens using a two bone cut technique that is efficient and reproducible. These specimens have the necessary anatomical bony landmarks for studying the complexity, utility, and limitations of lateral and posterolateral approaches to the skull base, important for the education of otolaryngology residents and fellows.  相似文献   
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Lymph node staging is of crucial importance for the therapy stratification and prognosis estimation in colon cancer. Beside the detection of metastases,the number of harvested lymph nodes itself has prognostic relevance in stage Ⅱ/Ⅲ cancers. A stage migration effect caused by missed lymph node metastases has been postulated as most likely explanation for that. In order to avoid false negative node staging reporting of at least 12 lymph nodes is recommended. However,this threshold is met only in a minority of cases in daily practice. Due to quality initiatives the situation has improved in the past. This,however,had no influence on staging in several studies. While the numbers of evaluated lymph nodes increased continuously during the last decades the rate of node positive cases remained relatively constant. This fact together with other indications raised doubts that understaging is indeed the correct explanation for the prognostic impact of lymph node harvest. Several authors assume that immune response could play a major role in this context influencing both the lymph node detectability and the tumor's behavior. Further studies addressing this issue are need. Based on the findings the recommendations concerning minimal lymph node numbers and adjuvant chemotherapy should be reconsidered.  相似文献   
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目的:分析和比较不同部位及不同采收期蕲艾精油含量与化学成分的差异,为蕲艾的综合开发与合理利用提供科学依据。方法:采用水蒸气蒸馏法(SD)提取蕲艾叶、蕲艾花、蕲艾茎及5月至10月不同采收期的蕲艾叶精油,结合气相色谱-质谱联用技术(GC-MS)分析其化学组成。结果:蕲艾叶精油含量显著高于蕲艾花与蕲艾茎,且蕲艾叶精油化学成分种类与相对含量均高于蕲艾花与蕲艾茎。不同采收期蕲艾精油提取率存在较大差异,其中6月蕲艾精油含量最高。经SD-GC-MS分析表明,不同采收期蕲艾精油均检测出含量较高的桉油精、樟脑、冰片和α-蒎烯等。结论:蕲艾叶为蕲艾的最佳药用部位,且6月为蕲艾的最佳采收期。  相似文献   
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At Queens Medical Centre, Nottingham, alveolar bone grafts (ABG) for patients with cleft lip and palate (CLP) were performed by two surgeons following the same surgical protocol, but with different postoperative iliac crest donor site analgesia: surgeon A used a donor site bolus of levobupivacaine, whilst surgeon B used a donor site epidural catheter (EC) infusing levobupivacaine. A healthcare evaluation was conducted in two phases to establish the effectiveness of analgesia for CLP patients undergoing ABGs. Data were collected prospectively in 2016 and 2018. Cleft patients postoperative to ABG were included. Outcome measures were pain scores at 2, 4, 6, 12, and 24 hours, time to mobilization, and time to food intake. Mean pain scores at the first evaluation were <1 out of 10 for all time points, except 24 hours (score 2.0 for bolus, 1.8 for EC). There was no statistically significant difference between the groups for any of the outcomes measured. As EC conferred no advantage, surgeon B changed to bolus administration and a second evaluation was performed. The mean pain score for the second evaluation was 1.7 and higher pain scores were more common with lower doses of levobupivacaine. The data suggest that bolus injection can produce safe, effective pain control provided an adequate dose is given.  相似文献   
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In Australia, during the 2010 Southern Hemisphere (SH) influenza season, there was an unexpected increase in post-marketing adverse event reports of febrile seizures (FS) in children under 5 years of age shortly after vaccination with the CSL 2010 SH trivalent influenza vaccine (CSL 2010 SH TIV) compared to previous CSL TIVs and other licensed 2010 SH TIVs. In an accompanying study, we described the contribution to these adverse events of the 2010 SH influenza strains as expressed in the CSL 2010 SH TIV using in vitro cytokine/chemokine secretion from whole blood cells and induction of NF-κB activation in HEK293 reporter cells. The aim of the present study was to identify the root cause components that elicited the elevated cytokine/chemokine and NF-κB signature. Our studies demonstrated that the pyrogenic signal was associated with a heat-labile, viral-derived component(s) in the CSL 2010 SH TIV. Further, it was found that viral lipid-mediated delivery of short, fragmented viral RNA was the key trigger for the increased cytokine/chemokine secretion and NF-κB activation. It is likely that the FS reported in children <5 years were due to a combination of the new influenza strains included in the 2010 SH TIV and the CSL standard method of manufacture preserving strain-specific viral components of the new influenza strains (particularly B/Brisbane/60/2008 and to a lesser extent H1N1 A/California/07/2009). These combined to heighten immune activation of innate immune cells, which in a small proportion of children <5 years of age is associated with the occurrence of FS. The data also demonstrates that CSL TIVs formulated with increased levels of splitting agent (TDOC) for the B/Brisbane/60/2008 strain can attenuate the pro-inflammatory signals in vitro, identifying a potential path forward for generating a CSL TIV indicated for use in children <5 years.  相似文献   
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Fish stocks experiencing high fishing mortality show a tendency to mature earlier and at a smaller size, which may have a genetic component and therefore long-lasting economic and biological effects. To date, the economic effects of such ecoevolutionary dynamics have not been empirically investigated. Using 70 y of data, we develop a bioeconomic model for Northeast Arctic cod to compare the economic yield in a model in which life-history traits can vary only through phenotypic plasticity with a model in which, in addition, genetic changes can occur. We find that evolutionary changes toward faster growth and earlier maturation occur consistently even if a stock is optimally managed. However, if a stock is managed optimally, the evolutionary changes actually increase economic yield because faster growth and earlier maturation raise the stock’s productivity. The optimal fishing mortality is almost identical for the evolutionary and nonevolutionary model and substantially lower than what it has been historically. Therefore, the costs of ignoring evolution under optimal management regimes are negligible. However, if fishing mortality is as high as it has been historically, evolutionary changes may result in economic losses, but only if the fishery is selecting for medium-sized individuals. Because evolution facilitates growth, the fish are younger and still immature when they are susceptible to getting caught, which outweighs the increase in productivity due to fish spawning at an earlier age.  相似文献   
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