全文获取类型
收费全文 | 1180篇 |
免费 | 66篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 42篇 |
妇产科学 | 17篇 |
基础医学 | 124篇 |
口腔科学 | 18篇 |
临床医学 | 55篇 |
内科学 | 228篇 |
皮肤病学 | 68篇 |
神经病学 | 46篇 |
特种医学 | 93篇 |
外科学 | 140篇 |
综合类 | 10篇 |
预防医学 | 54篇 |
眼科学 | 126篇 |
药学 | 36篇 |
肿瘤学 | 191篇 |
出版年
2023年 | 9篇 |
2022年 | 17篇 |
2021年 | 27篇 |
2020年 | 18篇 |
2019年 | 24篇 |
2018年 | 26篇 |
2017年 | 20篇 |
2016年 | 33篇 |
2015年 | 40篇 |
2014年 | 37篇 |
2013年 | 55篇 |
2012年 | 74篇 |
2011年 | 76篇 |
2010年 | 57篇 |
2009年 | 47篇 |
2008年 | 68篇 |
2007年 | 92篇 |
2006年 | 77篇 |
2005年 | 50篇 |
2004年 | 69篇 |
2003年 | 59篇 |
2002年 | 61篇 |
2001年 | 12篇 |
2000年 | 12篇 |
1999年 | 13篇 |
1998年 | 21篇 |
1997年 | 17篇 |
1996年 | 15篇 |
1995年 | 10篇 |
1994年 | 13篇 |
1993年 | 6篇 |
1992年 | 12篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 6篇 |
1984年 | 7篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1970年 | 2篇 |
1968年 | 4篇 |
1967年 | 2篇 |
排序方式: 共有1254条查询结果,搜索用时 31 毫秒
1.
Regional fractional ventilation mapping in spontaneously breathing mice using hyperpolarized 129Xe MRI 下载免费PDF全文
Hirohiko Imai Hironobu Matsumoto Erika Miyakoshi Shintaro Okumura Hideaki Fujiwara Atsuomi Kimura 《NMR in biomedicine》2015,28(1):24-29
The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
2.
Jhoji Tanabe Hirohiko Nakazato Hisayoshi Tanabe Hidetoshi Hanasaki Kazuo Kawasaki Daizo Yonemura 《Documenta ophthalmologica. Advances in ophthalmology》1986,63(2):165-171
The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans. 相似文献
3.
4.
Takeda H Matsumura Y Kuwata S Nakano H Shanmai J Qiyan Z Yufen C Kusuoka H Matsuoka M 《International journal of medical informatics》2004,73(3):311-316
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security. 相似文献
5.
Yoshimoto M Chang H Shiota M Kobayashi H Umeda K Kawakami A Heike T Nakahata T 《Stem cells (Dayton, Ohio)》2005,23(5):610-618
Recent studies have indicated that bone marrow cells can regenerate damaged muscles and that they can adopt phenotypes of other cells by cell fusion. Our direct visualization system gave evidence of massive muscle regeneration by green fluorescent protein (GFP)-labeled CD45+c-Kit+Sca-1+Lin- cells (KSL cells), and we investigated the role of KSL cells in muscle regeneration after transplantation with or without lethal irradiation. In the early phase, GFP signals were clearly observed in all the muscles of only irradiated mice. Transverse cryostat sections showed GFP+myosin+ muscle fibers, along with numerous GFP+ hematopoietic cells in damaged muscle. These phenomena were temporary, and GFP signals had dramatically reduced 30 days after transplantation. After 6 months, GFP+ fibers could hardly be detected, but GFP+c-Met+ mononuclear cells were located beneath the basal lamina where satellite cells usually exist in both conditioned mice. Immunostaining of isolated single fibers revealed GFP+PAX7+, GFP+MyoD+, and GFP+Myf5+ satellite-like cells on the fibers. Single-fiber cultures from these mice showed proliferation of GFP+ fibers. These results indicate two different roles of KSL cells: one leading to regeneration of damaged muscles in the early phase and the other to conversion into satellite cells in the late phase. 相似文献
6.
Hirano H Ezura Y Ishiyama N Yamaguchi M Nasu I Yoshida H Suzuki T Hosoi T Emi M 《Journal of human genetics》2003,48(6):288-292
Natural tooth loss represents a major medical issue within the elderly population, since it impairs masticatory function critical
for oral intake of essential nutrition. Contribution of genetic factors has been implicated in the determination of natural
tooth loss; degree of reduction in number of natural teeth remaining intact (NTI) varies among individuals; thus, heterogeneity
in NTI might reflect genetic variation within the population. One candidate gene, the matrix Gla protein gene (MGP), has been implicated in the pathogenesis of bone loss through a repression of bone/tooth formation. We have investigated
a possible association between the CA repeat polymorphism at the human MGP gene locus and the NTI in 458 elderly Japanese women. In 916 chromosomes tested, ten alleles of the polymorphic nucleotide
repeat were observed (designated A1–A10), among which five alleles were regarded as major alleles to be tested for the association.
Twenty-seven women who possessed an A6 allele (164 bp) had significantly higher NTI than the remaining participants (n=431), who did not carry an allele of that size (mean: 10.0 teeth vs 5.6 teeth; P=0.007, Mann-Whitney test). An eight-year longitudinal follow-up study of NTI suggested that the genetic variations at the MGP locus did not affect the rate of tooth loss in the elderly period. These results suggest that genetic variation at the MGP gene locus is associated with some determinants for tooth loss in elderly women. 相似文献
7.
Glucagon-induced somatostatin release from perifused rat hypothalamus: calcium dependency and effect of cysteamine treatment 总被引:1,自引:0,他引:1
Somatostatin (SRIF) release from rat hypothalamus was investigated in vitro with a perifusion system. Glucagon (1 microM) and high potassium concentrations (56 mM) stimulated SRIF release in a calcium-dependent manner. Pretreatment of the rat with cysteamine (30 mg/100 g body weight, 7 h earlier) significantly reduced SRIF release from the hypothalamus in glucagon- and high potassium-stimulated states as well as in the basal state. SRIF release from rat hypothalamus was also stimulated by both dibutyryl cyclic AMP (1 mM) and theophylline (3 mM). These results suggest that glucagon, acting in a calcium-dependent manner and possibly through the adenylate cyclase-cyclic AMP system, stimulates SRIF release from rat hypothalamus and that cysteamine treatment reduces releasable SRIF in the hypothalamus. 相似文献
8.
Motomaro Nakajima Hiroyuki Narnbu Nobuaki Shikata Hideto Senzaki Hirohiko Miki Airo Tsubura 《Pathology international》1996,46(11):874-882
Pigmentary degeneration of the retina was induced by a single intraperitoneal Injection of 75mgkg of N-methyl-N-nitrosourea (MNU) In female Brown-Norway colored rats at 50 days of age, which were then observed at 24, 48 and 72 h and 7, 21,35 and 150 days after the treatment. MNU-treated rats showed selective destruction of the photoreceptor cells by an apoptotic mechanlsm 24 h after the treatment, and the destruction was completed by day 7. During the photoreceptor cell degeneration, proliferation of Miller cells and infiltratlon of macrophages was prominent 72h and 21 days aRttr the treatment, respectively. Müller cell proliferation and macrophage infiltratbn corresponded to degenerative photo-receptor cell phagocytosis, and prollferating Müller cell processes responded to stabilize the damaged retina. Pigment epithelial cell detachment from the Bruch's membrane was seen 72 h after the treatment, and migration within all layers of the retina was seen at day 7 when photoreceptor Cells were lost. At 21, 35 and 150 days after the treatment, lack of photoreceptor cells and deposition of pigment epithelial cells within the retina but not in contact to vascular endothe-lial cells were characteristic. MNU-induced photoreceptor apoptosis followed by Miiller cell and macrophage reaction then pigment epithellal cells deposition withln the retina partially resembles retinitis pigmentosa in humans. 相似文献
9.
Kunio Ichijima Hirohiko Yamabe Yoichiro Kobashi Takekuni Iwata 《Pathology international》1980,30(2):293-300
A case of a 41 years old Japanese woman with widely disseminated primary lung cancer (adenocarcinoma) metastasizing to renal cell carcinoma (hypernephroma) is presented together with a brief review of the literature. 相似文献
10.
The effects of inhalation of nebulized nitroglycerin on dogs with experimental pulmonary hypertension induced by U46619 总被引:3,自引:0,他引:3
龚方戚 《中华医学杂志(英文版)》2000,113(5):475-476
Tofindasafe,simple,effectiveandselectivepulmonaryvasodilator,wetestedtheeffectivenessandsafetyofinhalednebulizednitroglycerin(NebNTG)indogswithexperimentalpulmonaryhypertension(PH)inducedbycontinuousinfusionofathromboxaneanalogue(U46619)TheuseofintravenousN… 相似文献