全文获取类型
收费全文 | 9798篇 |
免费 | 474篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 167篇 |
妇产科学 | 126篇 |
基础医学 | 1208篇 |
口腔科学 | 224篇 |
临床医学 | 621篇 |
内科学 | 2409篇 |
皮肤病学 | 171篇 |
神经病学 | 460篇 |
特种医学 | 442篇 |
外科学 | 2215篇 |
综合类 | 56篇 |
一般理论 | 1篇 |
预防医学 | 326篇 |
眼科学 | 115篇 |
药学 | 510篇 |
中国医学 | 18篇 |
肿瘤学 | 1164篇 |
出版年
2023年 | 51篇 |
2021年 | 171篇 |
2020年 | 96篇 |
2019年 | 118篇 |
2018年 | 145篇 |
2017年 | 150篇 |
2016年 | 156篇 |
2015年 | 191篇 |
2014年 | 231篇 |
2013年 | 240篇 |
2012年 | 422篇 |
2011年 | 475篇 |
2010年 | 280篇 |
2009年 | 220篇 |
2008年 | 477篇 |
2007年 | 508篇 |
2006年 | 457篇 |
2005年 | 490篇 |
2004年 | 500篇 |
2003年 | 469篇 |
2002年 | 439篇 |
2001年 | 372篇 |
2000年 | 365篇 |
1999年 | 336篇 |
1998年 | 157篇 |
1997年 | 118篇 |
1996年 | 108篇 |
1995年 | 88篇 |
1994年 | 66篇 |
1993年 | 89篇 |
1992年 | 217篇 |
1991年 | 177篇 |
1990年 | 178篇 |
1989年 | 167篇 |
1988年 | 151篇 |
1987年 | 155篇 |
1986年 | 141篇 |
1985年 | 151篇 |
1984年 | 104篇 |
1983年 | 91篇 |
1979年 | 77篇 |
1978年 | 57篇 |
1977年 | 43篇 |
1974年 | 47篇 |
1973年 | 48篇 |
1971年 | 48篇 |
1970年 | 43篇 |
1969年 | 43篇 |
1968年 | 46篇 |
1967年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Shunsuke Iriyama Haruyo Yamanishi Naomi Kunizawa Tetsuji Hirao Satoshi Amano 《Experimental dermatology》2019,28(3):247-253
Daily exposure to sunlight is known to affect the structure and function of the epidermal basement membrane (BM), as well as epidermal differentiation and epidermal barrier function. The aim of this study is to clarify whether the inhibition of BM‐degrading enzymes such as heparanase and matrix metalloproteinase 9 (MMP‐9) can improve the epidermal barrier function of facial skin, which is exposed to the sun on a daily basis. 1‐(2‐hydroxyethyl)‐2‐imidazolidinone (HEI) was synthesized as an inhibitor of both heparanase and MMP‐9. HEI inhibited not only the BM damage at the DEJ but also epidermal proliferation, differentiation, water contents and transepidermal water loss abnormalities resulting from ultraviolet B (UVB). This was determined in this study by the use of UVB‐induced human cultured skins as compared with the control without HEI. Moreover, topical application of HEI improved epidermal barrier function by increasing water content and decreasing transepidermal water loss in daily sun‐exposed facial skin as compared with non‐treated skins. These results suggest that the inhibition of both heparanase and MMP‐9 is an effective way to care for regularly sun‐exposed facial skin by protecting the BM from damage. 相似文献
2.
3.
4.
5.
Aro Ino Tatsuya Hayashi Kazunori Yamashiro Tetsuji Cho Toshifumi Kishimoto 《Nihon Arukōru Yakubutsu Igakkai zasshi》2005,40(1):47-56
One hundred fifty-three inpatients with alcohol dependence syndrome were treated with the structured BDIM (Before-Discharge Intervention Method). 82 patients of them have participated to self-help group meetings or kept having therapy as our outpatients or inpatients during the study period. We chose the families of the 82 patients as our study subject Out of the study subjects who took part in BDIM, 64 families (117 persons) answered our questionnaire. Among them 63 families (101 persons) gave their described answers of impressions and opinions about BDIM, which were summarized as follows. (1) Through BDIM the family members gained second thought on their alcoholic family member (IP: identified patient) and they could tell their new view to IP. BDIM enabled them to tell IP their sincere feeling and hope for recovery of IP. BDIM empowered both IP and IP's family members. (2) The family members became to know IP's orientation on his or her disease. They came to know IP's denial and understand him or her as he or she was. (3) The family members felt emotional ties among themselves and IP through BDIM. When the family members of a dysfunctional family took part together in BDIM, they could know the feelings, thoughts, experiences and hopes one another. The family members had a precious experience of mutual understanding among themselves and IP to hope for recovery together. (4) The family members appreciated BDIM as a effective therapy. In BDIM many of them regarded highly of giving their letters to IP as a useful method to convey their feeling and thoughts calmly to IP. (5) On the other hand some family members pointed out the difficulty for themselves to write on BDIM. For family members who are not good at writing a letter or tend only to blame IP through their letters, writing and giving letters to IP is not appropriate as a therapy. If family members feel strong anxiety or fear, it is safe not to practice BDIM. 相似文献
6.
Yuji Masuda Toyonobu Yamashita Tetsuji Hirao Motoji Takahashi 《Skin research and technology》2009,15(2):224-229
Background/purpose: It is crucial to establish an accurate method for measuring skin pigmentation in cosmetic science and clinical dermatology. Here, we report a non-invasive precise method for measuring skin melanin content.
Methods: In order to determine the concentrations of melanin and hemoglobin in skin, we used the spectrum resolution (SR) method. In brief, the absorption spectrum of the skin was calculated from the reflection spectrum using a spectrophotometer. The concentrations of melanin and hemoglobin were then determined using a multiple regression analysis, assuming that the absorption spectrum of the skin is expressed as a linear summation of the absorptions of melanin and hemoglobin according to the Lambert–Beer law. The skin changes in the volar forearm, which had been irradiated by ultraviolet rays (UV), were observed daily by the SR method.
Results: A multiple regression analysis with an absorption spectrum of 500–700 nm was performed. The multiple correlation coefficient was 0.993, resulting in a satisfactory precise estimate of the concentrations of melanin. After UV irradiation, the concentration of melanin monitored by the SR method increased until 8 days and decreased gradually afterwards.
Conclusions: The SR method allows the evaluation of the changes of epidermal melanin induced by UV irradiation. 相似文献
Methods: In order to determine the concentrations of melanin and hemoglobin in skin, we used the spectrum resolution (SR) method. In brief, the absorption spectrum of the skin was calculated from the reflection spectrum using a spectrophotometer. The concentrations of melanin and hemoglobin were then determined using a multiple regression analysis, assuming that the absorption spectrum of the skin is expressed as a linear summation of the absorptions of melanin and hemoglobin according to the Lambert–Beer law. The skin changes in the volar forearm, which had been irradiated by ultraviolet rays (UV), were observed daily by the SR method.
Results: A multiple regression analysis with an absorption spectrum of 500–700 nm was performed. The multiple correlation coefficient was 0.993, resulting in a satisfactory precise estimate of the concentrations of melanin. After UV irradiation, the concentration of melanin monitored by the SR method increased until 8 days and decreased gradually afterwards.
Conclusions: The SR method allows the evaluation of the changes of epidermal melanin induced by UV irradiation. 相似文献
7.
M Oishi H Yokoyama N Abe K Iwasaki F Okuguchi K Kawai H Sugimoto H Takamura H Takeda K Doi K Hirao S Ikeda 《Diabetic medicine》2007,24(10):1149-1155
AIMS: To study the time and cost involved in the care of newly registered outpatients with Type 2 diabetes mellitus (DM), compared with patients with hypertension and/or hyperlipidaemia (HTL). METHODS: A total of 313 patients with DM and 58 patients with HTL without diabetes were registered on their first visits to 11 diabetes clinics across Japan. The time and cost involved in their care was recorded over the following 5 months. RESULTS: In the first 3 months, there was an extensive time commitment to both groups. The time spent by physicians was 1.5 times longer for DM than for HTL. The total care time spent by all the care providers for DM was twice that for HTL. The cost of DM care was twice that for HTL, with the cost of medicines excluded. However, half of the cost for DM was for laboratory tests. When these were excluded, and the remaining cost divided by the time spent, the amount for DM was half of that for HTL. Over the 5 months, mean glycated haemoglobin (HbA(1c)) in DM patients improved from 8.0% to 6.5%, and 72% of DM patients achieved the glycaemic target of HbA(1c) < or = 6.5%. CONCLUSIONS: DM care in a diabetes clinic requires a great deal more time and resources than HTL to achieve the best outcome. An educational system for self care, presently lacking in the primary care setting in Japan, would improve glycaemic control for DM patients in the community. 相似文献
8.
Kenichi Yokoyama Toshiaki Nitatori Nahoko Kanke Shinju Suzuki 《Magnetic resonance in medical sciences》2006,5(1):33-40
With the development of fast scan techniques and technical advances in software, cardiac MRI can now be used for morphological and functional evaluation of the heart with good reliability and high spatial and temporal resolution. Cardiac MRI is employed at many institutions, mainly for assessing ischemic heart disease. Cardiac MRI can be used to identify coronary artery stenosis, evaluate myocardial viability, assess left ventricular wall motion and function, measure coronary blood flow and flow reserve, and obtain other useful information for the diagnosis of ischemic heart disease in a single examination, serving as a true comprehensive cardiac study. With regard to the evaluation of coronary artery stenosis, new techniques, such as whole-heart coronary MRA, permit visualization of the coronary arteries to their peripheral branches without contrast agent. Good results have been reported for whole-heart MRA as compared with X-ray coronary angiography (CAG). Attempts to evaluate plaque characteristics by visualizing the walls of the coronary arteries have also been reported recently. Technical improvements have been made in myocardial perfusion MRI to detect myocardial ischemia and in delayed contrast-enhanced MRI to assess myocardial viability, and some researchers have recently reported that the diagnostic capabilities of these techniques match or surpass those of cardiac nuclear medicine studies. We outline the features of the latest MR imaging techniques for the diagnosis of ischemic heart disease, discuss their practical applications, and compare them with other imaging modalities. 相似文献
9.
M Tokitsu M Nakamura H Yokoyama H Watanabe M Hara K Takeuchi 《No shinkei geka. Neurological surgery》1990,18(2):189-192
Two cases of skullbase-penetrating injuries caused by umbrella tips are reported. Case 1: 24-year-old male. Admitted with disturbance of consciousness, left hemiparesis, nasal bleeding, and laceration of left lower eyelid because of having been stabbed by an umbrella tip. Pupils and fundi revealed no definite findings. Plain skull X-ray showed turbid ethmoid sinus and fracture of planum sphenoidale. Cranial CT showed right putaminal hematoma with intraventricular hemorrhage and pneumocephalus. Increased ICP necessitated surgery two days after the injury. Dural laceration of planum sphnoidale, laceration of left optic nerve, right rectal gyrus contusion and rebleeding from the right lenticulostriate branch were observed. Dural plasty and removal of hematoma with external decompression were carried out. He had a good postoperative course, but left visual loss and left hemiparesis remained. Case 2: 29-year-old male. Admitted with excoriation of his right nostril because of having been stabbed by an umbrella tip, severe headache, and nasal discharge. Oculomotor palsy was observed as well as CSF rhinorrhea and meningeal irritability. Plain skull X-ray showed niveau in sphenoidal sinus, pneumocephalus, and fracture of sella turcica. His complaint disappeared after conservative therapy. We reviewed the literature and found only 4 similar cases. The skullbase, because of its anatomical character, is likely to be penetrated in orbital and periorbital injury caused by umbrella tips. Cases which include disturbance of consciousness have a poor prognosis. We hope the fact that umbrella tips can easily become life-threatening objects will come to the attention of the general public so that similar cases may be avoided. 相似文献
10.