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21.
目的探讨微泡造影剂联合高强度聚焦超声治疗对实时监控超声声像图的影响。方法对20只山羊肝脏进行自身前后对照分组,观测靶区HIFU定点辐照前后的超声声像图面积和灰阶变化,并比较声像图面积与实际损伤的凝固性坏死灶最大切面面积。结果HIFU辐照后,全氟显组靶区声像图面积、灰阶值及形成的凝固性坏死灶最大切面面积均较对照组明显增高(P<0.05)。实际损伤切面面积与辐照结束后即刻、2min、5min及10min时的声像图比较,其比值分别为0.33±0.12、0.55±0.21、0.72±0.15、0.94±0.23。结论微泡造影剂可明显增强HIFU对山羊肝脏的作用效应,通过观察HIFU辐照过程中的声像图变化,可实时指导HIFU治疗和判断治疗效果。  相似文献   
22.
The genus Capripoxvirus (CaPV) comprises three members namely, sheep poxvirus (SPPV), goat poxvirus (GTPV) and lumpy skin disease virus (LSDV) affecting sheep, goats and cattle, respectively. CaPV infections produce similar symptoms in sheep and goats, and the three viruses cannot be distinguished serologically. Since there are conflicting opinions regarding the host specificity of CaPVs, particularly for goatpox and sheeppox viruses, the development of rapid genotyping tools will facilitate more accurate disease diagnosis and surveillance for better management of capripox outbreaks.This paper describes a species-specific, real time polymerase chain reaction (PCR), based on unique molecular markers that were found in the G-protein-coupled chemokine receptor (GPCR) gene sequences of CaPVs, that uses dual hybridization probes for their simultaneous detection, quantitation and genotyping.The assay can differentiate between CaPV strains based on differences in the melting point temperature (Tm) obtained after fluorescence melting curve analysis (FMCA). It is highly sensitive and presents low intra- and inter-run variation.This real time PCR assay will make a significant contribution to CaPV diagnosis and to the better understanding of the epidemiology of CaPVs by enabling rapid genotyping and gene-based classification of viral strains and unequivocal identification of isolates.  相似文献   
23.
Taste is one of the five senses that give ruminants and other animals an awareness of their environment, especially for food selection. The sense of taste, which recognizes sweet, bitter, salty, sour and umami basic tastes, is often considered of paramount importance as it is the last sense in use before foods are swallowed. It thus plays a fundamental biological role in aiding animals to regulate intake of suitable food and reject unsuitable food. However, despite potentially relevant production and welfare issues, only a few studies have investigated how ruminants perceive and evaluate the basic tastes. Here we review current knowledge on tasting abilities and hedonic value of basic tastes in domestic ruminants via the analysis of both their anatomical and neurological structures and their behavioral preferences.Studies of the organization and functioning of the anatomical and neurological structures responsible for the perception of taste in ruminants have shown that sheep, cattle and goats all have lingual receptors for all five basic tastes. However, these studies have mainly focused on the sweet and bitter tastes. They have shown in particular that cows have fewer genes coding for the bitter receptors than other mammals, making them more tolerant to this taste. This pattern has been linked to the differences in the range of toxins and so potentially in the occurrence of bitterness encountered by different species in their environment, depending on the nature of their diet. Studies of ruminant feeding behavior have shown that the taste inducing the greatest consensus in preferences is the umami taste, with a high positive hedonic value. The bitter taste seems to have a rather negative hedonic value, the salty taste either a positive or a negative one depending on body needs, while the sweet taste seems to have a positive value in cattle and goats but not in sheep. Finally, the hedonic value of the sour taste is uncertain. Besides the hedonic value, the animal may assign a signal value to the tastes. In ruminants, the unanimous preference for the umami taste, the need dependent preference for the salty taste, and the reluctance of sheep to associate a positive reward with the bitter taste suggest that these tastes would signal the presence of proteins, minerals and toxins, respectively.  相似文献   
24.
目的建立山羊双侧下颌骨牵张成骨实验动物模型,探讨硫酸钙人工骨对山羊下颌骨牵引成骨区新骨生成的作用及局部使用硫酸钙对血清总钙的影响。方法8只山羊随机分为A组(硫酸钙组)和B组(对照组).建立牵引成骨(Distraction Osteogenesis,DO)模型。A组预牵开3mm间隙,注入硫酸钙人工骨;B组常规牵引:两组均于术后第5天开始,以0.5mm/12h的速度牵引,A组连续牵引7d,B组连续牵引10d,两组颌骨总延长距离均达到10mm。术前及术后早期检测血清碱性磷酸酶(ALP)和血清总钙浓度。牵引结束后第6周取材,对新生骨大体标本、影像学、组织学、骨密度及生物力学等指标进行观察检测。结果所有山羊下颌骨均延长了约10/mm,A组血清ALP浓度、新生骨小梁面积百分比、骨密度及三点弯曲断裂最大载荷值均比B组高(P〈0.05),而血清总钙浓度与B组相比差别无显著性(P〉0.05)。结论动物实验表明,硫酸钙人丁骨在牵引成骨的早期对新骨的形成具有促进作用.且局部应用硫酸钙对血清总钙浓度无明显影响.具有良好的生物相容性。  相似文献   
25.
Prion protein genetics plays a central role in transmissible spongiform encephalopathies, a disease occurring in human and animals. Here we report a 27-kb genomic sequence containing the goat PRNP gene. It shows, both in structure and content, a remarkable similarity with its sheep ortholog and can serve as a basis for future (comparative) studies with reference to the regulation of PRNP gene expression and the search for genetic tools to prevent/control/eradicate (goat) TSE. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The nucleotide sequence data reported in this paper has been submitted to the GenBank nucleotide sequence database and has been assigned the accession number EU870890.  相似文献   
26.
目的建立山羊下颌骨牵张成骨实验动物模型,探讨注射式硫酸钙对牵张成骨的促进作用。方法手术截断14只山羊的单侧下颌骨并埋入骨牵张器后,随机分为A、B两组,A组山羊在牵张成骨的同时注射硫酸钙,B组山羊单纯牵张成骨,通过对比得出结论。结果14只山羊的下颌骨被成功牵张7mm,牵张间隙内新骨形成。X线、病理、生物力学检测结果显示A组山羊下颌骨的牵张间隙内有更多新骨形成,愈合后的抗压能力更强。结论注射式硫酸钙对牵张成骨有促进作用。即在相同的牵张成骨、骨骼愈合时间内,硫酸钙可以促进牵张间隙内更多的新骨形成,使愈合后骨骼的强度更大。  相似文献   
27.
目的 采用二抗-甲状腺素抗体固相两步包被法,使用鲁米诺-双氧水-辣根过氧化物酶化学发光体系作为检测体系,建立测定血清中游离甲状腺素的化学发光免疫分析方法.方法 利用竞争法建立游离甲状腺素的检测体系,分别对该体系进行分析性能评估、2016年度内分泌室间质评,并与进口全自动发光试剂盒检测结果进行一致性检验.结果在4~64pmol/L的校准曲线范围内相关系数0.9995,最低检出限为0.54pmol/L,批内和批间精密度均小于7.0%,稳定性结果良好,不影响检测结果.2016年全国室间质评测定结果均在允许范围内,与进口西门子发光试剂盒有很好的临床符合性,两种试剂盒的样本测值差异不具有统计学意义.结论 本方法利用二抗-甲状腺素抗体固相两步包被法,在节约包被原料的同时改善了精密度且提高了灵敏度,最后通过临床血样的一致性评价,与参比试剂盒具有同等的临床使用价值.  相似文献   
28.
目的研究普罗帕酮转复心房颤动(简称房颤)时左上肺静脉(LSPV)和左房(LA)外膜电图的变化,分析普罗帕酮转复房颤的可能机制。方法在6只山羊的LA前壁及LSPV根部外膜缝合电极片,LA快速刺激诱发房颤,在房颤自发维持超过24h后,静脉滴注普罗帕酮直至房颤终止。分析用药前、后房颤波周长(AFCL)分别延长40,80ms和房颤转复前各16s的间期内,LSPV和LA外膜电图的变化规律。结果6只山羊在经过静脉滴注普罗帕酮后,全部转复为窦性心律。用药前的LSPV的AFCL显著短于LA(P<0.05);用药后LSPV和LA的AFCL都出现逐渐延长,在房颤转复前两者趋于一致。用药前LSPV双电位和碎裂电位的百分比显著高于LA,单电位比例显著低于LA(P<0.05);用药后,LA和LSPV单电位百分比逐渐增加,双电位和碎裂电位逐渐减少,但在LA双电位和碎裂电位的比例始终小于LSPV(P<0.05);在房颤终止前LA先于LSPV出现双电位和碎裂电位的显著减少或消失,当LSPV的双电位和碎裂电位消失后房颤才终止。结论在本模型中,普罗帕酮对左房、肺静脉电生理的影响在房颤的转复过程中起着重要的作用。  相似文献   
29.
目的探讨左房快速起搏对肺静脉口、左右心耳电重构的影响。方法运用快速起搏左心耳的方法建立心房颤动(AF)模型,在起搏前及起搏后的第1,3,5,7d对左、右心耳;左上、左下肺静脉口;右上、右下肺静脉口的有效不应期(ERP)、ERP频率适应性、ERP离散度及心房间的传导时间进行测定。采用S1S2程序刺激,基础起搏周长(PCL)分别为400,300,200ms,S2为200ms,以5ms的步长递减。程序刺激结合Burst刺激对上述心房部位进行AF的诱发,记录AF的发生率。在第8天关闭起搏器,采用上述相同方法对起搏停止后即刻;2,4,6,24h的上述各部位的ERP进行测定。结果起搏1d后各个基础起搏周长下各部位的ERP明显缩短,ERP频率适应性降低,ERP离散度增大(P<0.05),而心房间传导时间无明显变化(P>0.05);起搏终止后各部位的ERP逐渐延长,但起搏终止后6hERP与快速起搏前相比仍有明显缩短(P<0.05);24h后ERP基本恢复到起搏前水平,两者相比无明显差异(p>0.05);随着起搏时间的延长各部位AF的诱发率逐渐增高(P<0.05)。结论快速心房起搏不仅引起心房肌电重构,亦引起肺静脉电重构。  相似文献   
30.
It has been postulated that the cortical EEG might reveal behavioural or physiological states associated with rumination. This paper reports that the EEG of ruminants recorded during rumination or nonrumination shows a marked polymorphism varying from irregular low amplitude waves associated with the aroused state to irregular waves of very low frequency and high amplitude similar to delta waves of man. No particular pattern of EEG was a prerequisite for the onset, continuation or discontinuation of rumination. Analysis of our data suggests that rumination occurs concurrently with any of the elements of the polymorphous EEG except during the alert state, feeding and REM sleep. In the period immediately prior to rumination physiological adaptation may occur which brings the level of consciousness towards the aroused state. The present study produced no evidence to correlate the EEG with rumination and therefore refutes earlier suggestions and thus fails to throw light on the central nervous origin of the complex behavioural pattern known as rumination.  相似文献   
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