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61.
Seven cases of granular cell Abrikossoff tumours of the larynx and tongue are reported: four in the tongue and three in the larynx. All of these tumours were removed with the carbon dioxide (CO2) laser. The anatomical site of the origin and clinical features of granular cell tumours (GCT) are not specific. Histological, light microscopic, electron microscopic (EM) and immunohistochemical studies are required for diagnosis. The histogenesis and cellular derivation of GCTs is still controversial. The biological potential and lack of cellular atypia define a benign process. However, it is important to take into account that these tumours have ill-defined borders without a capsule. Radiation therapy has proved ineffective in the past. Surgical excision with a wide margin is required. Because of numerous advantages, for example, no bleeding, no oedema, minimal pain and quick recovery, CO2 laser removal is the treatment of choice. The authors have not seen any recurrence or complications. 相似文献
62.
A significant increase of cutaneous laser Doppler flowmetry was found before blood flow decreases with increasing pressure during a 5 mmHg min−1 increase of pressure strain on the finger. Pre-treatment with a local anaesthetic or chronically applied capsaicin, resulted in the disappearance of the vasodilatory response. These results suggest an original vasodilatory axon reflex response to non-noxious pressure strain which is initiated by capsaicin-sensitive nerve terminals in the human skin. 相似文献
63.
Nd:YAG激光虹膜透切术治疗闭角型青光眼406只眼。单脉冲激光能量为3~6mJ,平均总能量为186mJ。一次虹膜透切成功者占80.0%,二次治疗成功者为17.2%,需三次治疗者仅为2.8%。治疗后随访0.5~1.0年,眼压平均下降0.78kPa(5.87mmHg)。视力有明显提高达55.5%,保持原来视力不变者为41.0%,视力微有减退者为3.5%。治疗效果显著,无严重并发症。 相似文献
64.
Per R. Flood Peter Fritz Schmidt Gro R. Wesenberg Hermod Gadeholt 《Archives of toxicology》1988,62(4):295-300
Two iliac crest needle biopsies were taken from a 43-year-old lead-poisoned woman during and after completion of a Ca-EDTA treatment. By atomic absorption spectroscopy the first and second biopsy were found to contain 56, respectively 41.6 g lead/g wet tissue. In both biopsies 36% of the lead was extractable in 0.1 N HCl. Electron microbeam X-ray analysis proved to have too low sensitivity for quantitation of the lead in these biopsies. Laser microbeam mass analysis (LAMMA), performed only on the second biopsy, revealed a high and fairly constant residual lead concentration in all bone marrow cell nuclei (approximately 55 g/g) and a low lead concentration in the cytoplasm of the same cells (4–12 (g/g). The extracellular bone matrix lead was greatly concentrated in the superficial 3–6 m osteoid zone of the bony trabeculae and totally absent from deeper parts of the mineralized matrix. The LAMMA results are in good agreement with those of subcellular fractionation experiments and atomic absorption spectroscopy, provided that the relative volume fraction of nucleus and cytoplasm is accounted for. The high residual osteoid lead after completed chelation therapy indicates that lead has a stronger affinity for the organic than the mineral components of bone matrix. 相似文献
65.
In in vitro and animal experiments the tissue effects of the 1.318m Nd-YAG laser were compared to those of the standard 1.064m Nd-YAG laser in order to evaluate the advantages of the new wavelength with a ten times higher absorption in water for gastroenterological tumour treatment. Under irradiation parameters related to clinical endoscopic practice, the laser of the wavelength 1.318m needs for both vaporization and coagulation significantly less energy than the 1.064m laser. Since vaporization at 1.318m is always accompanied by a higher coagulation effect compared to 1.064m the risk of late necrosis and resulting perforation appears to be increased. 相似文献
66.
高压氧对人重症牙周炎牙龈血流量、血流速度和血浓度作用及机理研究 总被引:4,自引:2,他引:4
目的 :探讨高压氧 (HBO)对人重症牙周炎牙龈血流量 (GBF)、血流速度 (BCV)和血浓度 (BC)的作用及HBO治疗牙周炎的机理。方法 :选自口腔中心门诊的 3 0例重症牙周炎患者 ,随机分为二组 ,即治疗组和对照组 ,治疗组用HBO治疗 ,对照组用漱口液漱口。用激光多普勒血流仪测定二组治疗前后的GBF、BCV和BC。结果 :HBO能使牙周炎患者GBF增加 2 .1倍 ,BCV增加 6.7倍 ,BC降低为治疗前的 5 8.2 % ,与对照组比均有非常显著性差异 (P <0 .0 1)。结论 :HBO能使牙周炎患者GBF和BCV增加 ,BC减少 ,能改善牙龈微循环 ,对治疗牙周炎有积极意义 相似文献
67.
为克服 He-Ne激光血管内照射疗法所具有的不足,我们采用830nm、500mW半导体激光器,研制了用于体外血管照射的激光治疗仪.设计了易于固定的激光输出头,并且采用单片机控制整机,提高了仪器的稳定性和可靠性.临床应用取得了令人满意的治疗效果. 相似文献
68.
Laser Doppler perfusion monitoring and imaging technologies generate time traces and two-dimensional flow maps of the microcirculation.
With the goal of reaching different tissue depths, these technologies are equipped with lassers operating at different wavelengths
λ. The fact that the average scattering angle, at a single scattering event, between a photon and a red blood cell increases
with λ is compensated for by a 1/λ effect in the scattering vector, rendering the average frequency shift virtually independent
of the choice of wavelength. Monte Carlo simulations showed that the corresponding spectral signature of the Doppler signals
for λ=632.8nm and 780nm were close to identical. The theoretical predictions were verified by calculating the centre-of-gravity
(COG) frequency of the laser Doppler power spectral density for the two wavelengths from forearm and finger skin, representing
a low and high perfusion area, respectively (forearm COG=123 against 121Hz, finger COG=220 against 212 Hz). When the wavelength
changes from 632.8nm to 780nm, the heterodyne efficiency of the detector and, thereby, the inherent system amplifcation increase.
For tissues with identical microvascular flow conditions, the output signal therfore tends to increase in magnitude when shifting
to longer wavelengths. 相似文献
69.
大鼠三叉神经脊束间质核内内脏神经初级传入终末与NOS阳性投射神经元的联系 总被引:1,自引:0,他引:1
目的 探查间质核 (INV)内内脏传入终末与向臂旁核 (PBN)投射的NOS阳性神经元之间的联系。 方法 逆行、跨神经节追踪以及免疫荧光组织化学方法 ,结合激光共聚焦扫描显微镜观察。 结果 PBN内注射四甲基罗丹明 (TMR)后 ,逆行标记细胞主要位于注射侧的INV ,大多属 2 0 μm以下的中、小型细胞。NOS阳性细胞与TMR逆行标记细胞分布区域重叠。NOS TMR双标记细胞分别占NOS阳性细胞总数的 5 4 8% (17 31)和TMR逆行标记细胞总数的 34% (17 4 9)。舌咽和迷走神经内注射生物素化葡聚糖胺 (BDA)跨神经节标记的内脏神经初级传入终末点状膨体贴近双标记细胞胞体 ,呈紧密接触状。 结论 可能存在经INV向PBN投射的内脏伤害性信息传导通路 ,作为神经递质和神经信息分子的NO可能参与其内脏伤害性信息的传递和调控 相似文献
70.
Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo 总被引:1,自引:0,他引:1
L. J. BUSSAU L. T. VO P. M. DELANEY G. D. PAPWORTH D. H. BARKLA R. G. KING 《Journal of anatomy》1998,192(2):187-194
Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible. 相似文献