全文获取类型
收费全文 | 747篇 |
免费 | 37篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 18篇 |
妇产科学 | 4篇 |
基础医学 | 123篇 |
口腔科学 | 7篇 |
临床医学 | 66篇 |
内科学 | 183篇 |
皮肤病学 | 13篇 |
神经病学 | 102篇 |
特种医学 | 31篇 |
外科学 | 119篇 |
预防医学 | 15篇 |
眼科学 | 11篇 |
药学 | 21篇 |
肿瘤学 | 59篇 |
出版年
2023年 | 6篇 |
2022年 | 20篇 |
2021年 | 33篇 |
2020年 | 16篇 |
2019年 | 17篇 |
2018年 | 28篇 |
2017年 | 18篇 |
2016年 | 14篇 |
2015年 | 25篇 |
2014年 | 26篇 |
2013年 | 39篇 |
2012年 | 63篇 |
2011年 | 65篇 |
2010年 | 36篇 |
2009年 | 31篇 |
2008年 | 50篇 |
2007年 | 48篇 |
2006年 | 42篇 |
2005年 | 41篇 |
2004年 | 36篇 |
2003年 | 35篇 |
2002年 | 28篇 |
2001年 | 6篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 2篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有788条查询结果,搜索用时 0 毫秒
1.
2.
3.
Safety evaluation of surgical materials by cytotoxicity testing 总被引:2,自引:1,他引:1
The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton
types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate
and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum
essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected
for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For
Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in
the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of
the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that
the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid
false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the
cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo
use of biomaterials on surrounding cells, tissues, and organs. 相似文献
4.
Mitsuru Masaki Tadashi Kuroda Naoki Hosen Hisao Hirota Kazuo Terai Yuichi Oshima Yoshikazu Nakaoka Shoko Sugiyama Ryusuke Kimura Satoshi Yoshihara Manabu Kawakami Norishige Iizuka Yasuhiko Tomita Hiroyasu Ogawa Ichiro Kawase Keiko Yamauchi-Takihara 《Journal of the American Society of Echocardiography》2004,17(4):397-398
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography. 相似文献
5.
6.
OBJECTIVE: We investigate the synaptic factor for the recovery function of evoked responses using a repetitive stimulation technique. METHODS: Somatosensory evoked cortical magnetic field (SEF) was recorded following stimulation of the median nerve using single to 6-train stimulation in 8 healthy subjects. The SEF responses after each stimulus in the train stimulation were extracted by subtraction of the waveforms. RESULTS: An attenuation of the SEF components was recognized after the second of the stimuli, but there was no significant attenuation with the third or later stimulations. The root mean square (RMS) of the 1M (peak latency at 20 ms after stimulation) and 4M (70 ms) components were smaller than that of the single stimulation during the train stimulation, while the 2M (30 ms) and 3M (45 ms) components were not attenuated, but the 3M was facilitated at the fourth to sixth stimulation. CONCLUSION: The synaptic factor was not responsible for the attenuation of the SEF components during repetitive stimulation in healthy subjects. The SEF change disclosed a functional difference among the SEF components during the train stimulation, especially among the later components. 相似文献
7.
Murakami R Obara H Momota T Tanaka A Nakamura H Mikawa K Iwai S 《Journal of anesthesia》1989,3(2):149-154
Morphological alterations in the lungs of rats deficient in either or both of vitamin E and essential fatty acids were investigated after exposure to hyperoxia for 48h. In rats deficient in both vitamin E and essential fatty acids, there was damage to type-2 alveolar cells observed as swollen mitochondria and bleb formation in the cytoplasm. None of these changes was found in rats deficient in only one of these substances. Hyperoxia in rats deficient in both substance also caused destruction of the capillary endothelial cells and edema in the interstitium. The lungs of rats deficient in only one of the substances showed some edema in the capillary endothelial cells, but not destruction, and less interstitial edema. These findings suggest that simultaneous deficiency in vitamin E and essential fatty acids facilitates lung damage in rats exposed to hyperoxia.(Murakami R, Obara H, Momota T et al.: The effect of hyperoxia on the lungs of rats deficient in essential fatty acids. J Anesth 3: 149–154, 1989) 相似文献
8.
Polyelectrolyte complexes (PEC) were prepared from chitosan as the polycation and several synthesized functional anion polysaccharides, and their effects on cell attachment, morphology, proliferation and differentiation were estimated using normal human osteoblasts (NHOst). After a 1-week incubation, PEC made from polysaccharides having carboxyl groups as polyanions showed low viability of NHOst on it although the NHOst on it showed an enhancement in their differentiation level. On the other hand, NHOst on PEC made from sulfated or phosphated polysaccharides showed similar attachment and morphology to those on the collagen-coated dish. When the number of NHOst was estimated after 1 week, the number on the PEC was ranged from 70% to 130% of those on the collagen-coated dish, indicating few effects of these PEC on cell proliferation. In addition, NHOst on PEC films made from sulfated polysaccharides differentiated to a level very similar to that observed on the collagen-coated dish, indicating that these PEC films maintain the normal potential of NHOst to both proliferate and differentiate. Measurement of gap junctional intercellular communication of NHOst on PEC revealed that PEC did not inhibit communication, suggesting that PEC films have few effects on cell homeostasis. Thus, PEC made from the sulfated polysaccharide may be a useful material as a new scaffold for bone regeneration. 相似文献
9.
Ryusuke Nishimura Kazuhiro Okuno Takeshi Matsuo Nobuoki Mori 《Pathology international》1971,21(1):143-149
The clinical history and pathological findings of a 68-year-old female with mycosis fungoides were described.
Clinically she developed cutaneous eruptions, and plaques to nodules appearlng within the next 4 months. Histopathological examination at biopsy revealed mycosis fungoides. At autopsy, extensive visceral involvement was disclosed (lungs, liver, kidneys, spleen, esophagus, left adrenal gland, lumbar vertebral bone marrow, and lymph nodes). Acute exacerbation of pulmonary tuberculosis was thought to be a terminal event. 相似文献
Clinically she developed cutaneous eruptions, and plaques to nodules appearlng within the next 4 months. Histopathological examination at biopsy revealed mycosis fungoides. At autopsy, extensive visceral involvement was disclosed (lungs, liver, kidneys, spleen, esophagus, left adrenal gland, lumbar vertebral bone marrow, and lymph nodes). Acute exacerbation of pulmonary tuberculosis was thought to be a terminal event. 相似文献
10.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers. 相似文献