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1.
摘要 目的:分析血清生长分化因子15(GDF-15)、高敏心肌肌钙蛋白T(hs-cTnT)对冠状动脉旁路移植术后新发心房颤动(房颤)及近期主要心血管事件的预测效能。方法:选择自2020年1月至2022年1月在我院行冠状动脉旁路移植术的140例冠心病患者作为研究对象,根据术后是否新发房颤,分为房颤组(46例)和非房颤组(94例)。检测两组术前血清GDF-15、hs-cTnT水平,使用多因素Logistic回归分析血清GDF-15、hs-cTnT与术后新发房颤的关系;随访6个月,观察主要心血管事件发生情况,通过受试者工作特征曲线下面积(AUC)评价血清GDF-15、hs-cTnT对术后新发房颤及近期主要心血管事件的预测效能。结果:两组患者年龄、性别、体重指数等一般资料比较无差异(P>0.05);房颤组SYNTAX积分高于非房颤组,差异有统计学意义(P<0.05);房颤组血清GDF-15、hs-cTnT水平均高于非房颤组(P<0.05);经多因素Logistic回归分析,SYNTAX积分、血清GDF-15、hs-cTnT均是冠状动脉旁路移植术后新发房颤的独立预测因素(P<0.05);经ROC曲线分析,血清GDF-15联合hs-cTnT预测冠状动脉旁路移植术后新发房颤的AUC为0.933,大于SYNTAX积分的0.790,预测近期主要心血管事件的AUC为0.925,大于SYNTAX积分的0.750(P<0.05)。结论:血清GDF-15联合hs-cTnT对冠状动脉旁路移植术后新发房颤及近期主要心血管事件均具有良好的预测效能,值得临床予以重视。  相似文献   
2.
繁殖是植物种群更新与维持的重要环节。包括极小种群野生植物在内的受威胁物种, 其濒危原因是在长期演化过程中自身繁育力的衰退、生活力的下降等内在因素和人类的过度采挖和生境的破坏等外在因素共同作用的结果。对极小种群野生植物进行高效的人工繁殖, 能扩大种群数量并应用于迁地保护、自然回归和满足商品市场的需求, 有利于其种质资源的保护和可持续利用。为了保持物种的遗传多样性, 采用种子繁殖育苗是有效的方法, 扦插、嫁接和组织培养技术等无性繁殖方法则可用于对难以用种子繁殖的种类进行快速繁殖。本文对14种中国典型极小种群野生植物的繁殖特性和已有的人工繁殖方法进行了综述, 并简要介绍在其种苗繁殖研究方面取得的进展。其中利用播种繁殖成功的物种有12种, 共繁殖230,000株种苗; 利用扦插繁殖成功的物种有5种, 共繁殖33,100株种苗; 华盖木(Manglietiastrum sinicum)、河北梨(Pyrus hopeiensis)和黄梅秤锤树(Sinojackia huangmeiensis)采用嫁接繁殖出了2,415株种苗; 9个物种的组织培养技术获得成功, 共繁殖了24,850株种苗。这些种苗有些已应用于迁地保护和自然回归。上述研究结果为这14种极小种群野生植物的保护和利用提供了理论和技术基础, 也能为其他极小种群野生植物的保护和利用提供参考。  相似文献   
3.
Aim: To find out risk factors for postoperative cognitive dysfunction (POCD) after coronary artery bypass grafting (CABG), and to provide basis for clinical prevention of POCD. A total of 88 patients who underwent CABG were surveyed with Telephone Questionnaire (TICS-M) for their cognitive impairment after 3, 7, 21, 90, 180 days post-surgery. The occurrence of POCD was diagnosed by Neuropsychological Battery which included Vocabular Learning Test (VLT), Wisconsin Card Sorting Test (WCST), Trail Making Test (TMT) and Symbol Digit Modalities Test (SDMT). The preoperative, intraoperative and postoperative risk factors were assessed by the χ2 or t test. Multivariate analysis was used to study the correlation between the risk factors and the occurrence of POCD. Age, aortic plaque, carotid artery stenosis, cerebrovascular disease, anesthesia time, the rate of decline in intraoperative hemoglobin concentration (ΔHb) and systemic inflammatory response syndrome (SIRS) score on postoperative day 2 had statistically significant (P<0.05) influence on the occurrence of POCD. Aortic plaque, carotid artery stenosis, anesthesia time and SIRS score (odds ratio (OR) value > 1, P<0.05) are the risk factors for POCD. The incidence of day-21 and -180 POCD was approximately 26.1 and 22.7%, respectively.  相似文献   
4.
Netherlands Heart Journal - After coronary artery bypass grafting (CABG), healthcare utilisation is high and is partly unplanned. eHealth applications have been proposed to reduce healthcare...  相似文献   
5.
The treatment of osteochondral articular defects has been challenging physicians for many years. The better understanding of interactions of articular cartilage and subchondral bone in recent years led to increased attention to restoration of the entire osteochondral unit. In comparison to chondral lesions the regeneration of osteochondral defects is much more complex and a far greater surgical and therapeutic challenge. The damaged tissue does not only include the superficial cartilage layer but also the subchondral bone. For deep, osteochondral damage, as it occurs for example with osteochondrosis dissecans, the full thickness of the defect needs to be replaced to restore the joint surface 1. Eligible therapeutic procedures have to consider these two different tissues with their different intrinsic healing potential 2. In the last decades, several surgical treatment options have emerged and have already been clinically established 3-6.Autologous or allogeneic osteochondral transplants consist of articular cartilage and subchondral bone and allow the replacement of the entire osteochondral unit. The defects are filled with cylindrical osteochondral grafts that aim to provide a congruent hyaline cartilage covered surface 3,7,8. Disadvantages are the limited amount of available grafts, donor site morbidity (for autologous transplants) and the incongruence of the surface; thereby the application of this method is especially limited for large defects.New approaches in the field of tissue engineering opened up promising possibilities for regenerative osteochondral therapy. The implantation of autologous chondrocytes marked the first cell based biological approach for the treatment of full-thickness cartilage lesions and is now worldwide established with good clinical results even 10 to 20 years after implantation 9,10. However, to date, this technique is not suitable for the treatment of all types of lesions such as deep defects involving the subchondral bone 11.The sandwich-technique combines bone grafting with current approaches in Tissue Engineering 5,6. This combination seems to be able to overcome the limitations seen in osteochondral grafts alone. After autologous bone grafting to the subchondral defect area, a membrane seeded with autologous chondrocytes is sutured above and facilitates to match the topology of the graft with the injured site. Of course, the previous bone reconstruction needs additional surgical time and often even an additional surgery. Moreover, to date, long-term data is missing 12.Tissue Engineering without additional bone grafting aims to restore the complex structure and properties of native articular cartilage by chondrogenic and osteogenic potential of the transplanted cells. However, again, it is usually only the cartilage tissue that is more or less regenerated. Additional osteochondral damage needs a specific further treatment. In order to achieve a regeneration of the multilayered structure of osteochondral defects, three-dimensional tissue engineered products seeded with autologous/allogeneic cells might provide a good regeneration capacity 11.Beside autologous chondrocytes, mesenchymal stem cells (MSC) seem to be an attractive alternative for the development of a full-thickness cartilage tissue. In numerous preclinical in vitro and in vivo studies, mesenchymal stem cells have displayed excellent tissue regeneration potential 13,14. The important advantage of mesenchymal stem cells especially for the treatment of osteochondral defects is that they have the capacity to differentiate in osteocytes as well as chondrocytes. Therefore, they potentially allow a multilayered regeneration of the defect.In recent years, several scaffolds with osteochondral regenerative potential have therefore been developed and evaluated with promising preliminary results 1,15-18. Furthermore, fibrin glue as a cell carrier became one of the preferred techniques in experimental cartilage repair and has already successfully been used in several animal studies 19-21 and even first human trials 22.The following protocol will demonstrate an experimental technique for isolating mesenchymal stem cells from a rabbit''s bone marrow, for subsequent proliferation in cell culture and for preparing a standardized in vitro-model for fibrin-cell-clots. Finally, a technique for the implantation of pre-established fibrin-cell-clots into artificial osteochondral defects of the rabbit''s knee joint will be described.  相似文献   
6.
Abstract

From the measurements of the profiles of hydraulic conductance and water potential from soil through to the leaf system in fully established melon plants, the limits to water flow set by coupling of hydraulic conductance (k) with water relation parameters was evaluated in the laboratory using high pressure flow device (HPFM) and evaporative flux method (EF). The rootstock Arava was grafted onto self, and onto two genotypes (AR57 and AR82) using side and V graft types, and there was an ungrafted control. Hydraulic transport efficiency was estimated from measurements of evaporative flux (transpiration rate) and leaf water potential (ψL) measured between pre-dawn and sunset during the growth cycle. Measured parameters to characterize the hydraulic efficiency (architecture) of the vascular system of melon were normalized to areas of leaves and stem cross section; this enabled the examination of their physiological and ecological functions. The effects of rootstock genotype were more marked on graft union and scion water relations. Differences in the magnitudes of water relation parameters of hydraulic conductance, water potential (lwp) and evaporative water loss (EF) were detected. AR/RS82 side grafted exhibited high EF and Kh despite its lower leaf water potential compared to AR/RS57 V grafted. Self grafting (Arava/Arava grafts) in melon seems to improve water relations and xylem water transport efficiency. Parameters describing the hydraulic efficiency (architecture) of vascular system of melon plants were described in relation to plant attributes. The expression of hydraulic conductance of the root and shoot system relative to plant attributes did not eliminate differences in the magnitudes of conductance elements in tomato and melon. Differences obtained among the different melon grafts in whole plant leaf and stem area specific hydraulic conductance (Kl) indicate the carbon efficiency and hence the cost of resource allocation to areas of root surface and leaves. The role of plant water relations in root-shoot communications and whole plant regulation of water flux are inferred from this study.  相似文献   
7.
目的:比较邮票植皮、meek植皮以及自体微粒皮移植用于大面积烧伤患者创面修复的临床效果和可行性。方法:回顾性分析我院烧伤科收治的120例大面积烧伤患者的临床资料,根据不同的手术植皮方法分为微粒皮植皮组、Meek植皮组和邮票皮组,每组40例。三组患者入院后均给予常规基础治疗,再根据选择植皮方式的不同实施微粒皮植皮、Meek植皮和邮票皮植皮。对比三组患者的植皮成活率、创面一期愈合率、愈合时间、死亡率、1%烧伤面积(1%TBSA)治疗费用(元)以及康复效果(康复优良率)。结果:邮票皮组植皮成活率明显高于Meek植皮组(P0.05),Meek植皮组植皮成活率明显高于微粒皮植皮组(P0.05)。Meek植皮组和邮票皮组创面愈合时间均明显短于微粒皮植皮组(P0.05)。邮票皮组1%TBSA治疗费用明显低于Meek植皮组(P0.05),Meek植皮组1%TBSA治疗费用明显低于微粒皮植皮组(P0.05)。Meek植皮组和邮票皮组的创面一期愈合率均明显高于微粒皮植皮组(P0.05);Meek植皮组和邮票皮组的死亡率均明显低于微粒皮植皮组(P0.05);meek植皮组的瘢痕最轻,关节功能恢复最好;微粒皮植皮组瘢痕最重,关节功能恢复最差。结论:不同植皮方式用于大面积烧伤创面修复的临床效果各不相同。邮票皮成活率高、抗感染能力强,但扩张比例低,创面愈合效果差;meek皮扩张比例高、康复效果好,但抗感染能力差;微粒皮扩张比例最高,但成活率低,治疗成本高。临床上,应该根据患者的自身情况选择不同的植皮方式。  相似文献   
8.
目的:研究髋关节镜治疗髋关节疾病的方法、疗效及适应证,探讨髋关节镜在髋关节疾病中的临床价值。方法:研究对象为86例有明显髋关节疼痛的患者,包括股骨头坏死(osteonecrosis,ON)(43%)、盂唇损伤(20%)、退行性关节病变(degenerative joint disease,DJD)(10%)、股骨头骨骺缺血性坏死(Legg-Calve'-Perthes,LCP)(10%)、髋关节游离体(10%)、髋关节疼痛(100%)、机械性损伤(78%)、运动损伤(56%)。对患者采用仰卧位进行髋关节镜检查,使用牵引床,300或700,前外侧入口。观察不同疾病在治疗后的预后结果。结果:所有患者均无并发症,平均随访时间30个月,有60%的患者疼痛症状得到缓解。盂唇(91%,P0.003)或LCP(89%,P0.05)患者疗效较好,而ON和DJD患者疼痛症状缓解较差,改善率仅为40%和44%。在吻合血管游离腓骨移植(free-vascularized fibular graft,FVEG)的患者中有34%在随访期间得到改善(P=0.003)。其中18名患者(21%)进行了全髋关节置换术。结论:髋关节镜手术对于游离体、盂唇损伤、局灶性软骨病变、晚期LCP后遗症患者有良好的治疗效果;对股骨头坏死的治疗效果不佳。  相似文献   
9.
Diabetes mellitus (DM) is an important risk factor for adverse outcomes of coronary artery bypass grafting. The bypass grafts harvested from patients with DM tend to go into spasm after their implantation into the coronary circulation. To clarify the contribution of 5-hydroxytriptamine (5-HT) and angiotensin II (AngII) in the bypass graft spasm, we examined the contractile reactivity to 5-HT or AngII of isolated human endothelium-denuded saphenous vein (SV) harvested from DM and non-DM patients. The 5-HT-induced constriction of the SV was significantly augmented in the DM group than in the non-DM group, which is similar to our previous report. AngII-induced constriction of the SV was also significantly augmented in the DM group than the non-DM group. Especially in the non-DM group, the AngII-induced maximal vasoconstriction was markedly lower than the 5-HT-induced one. Meanwhile, the increasing rates of AngII-induced vasoconstriction in the DM group to the non-DM group were significantly greater than those of 5-HT-induced vasoconstriction. These results indicate that 5-HT is a potent inducer of SV graft spasm in both DM and non-DM patients, while AngII is a potent inducer of SV graft spasm only in patients with DM. Furthermore, the protein level of AngII AT1 receptor (AT1R), but not the protein level of 5-HT2A receptor, in the membrane fraction of the SV smooth muscle cells of DM patients was significantly increased as compared with that of the non-DM patients. These results suggest that the mechanism for hyperreactivity to AngII in the SV from DM patients is due to, at least in part, the increase in the amount of AT1R on membrane of the SV smooth muscle cells.  相似文献   
10.
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