全文获取类型
收费全文 | 1110篇 |
免费 | 53篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 11篇 |
妇产科学 | 9篇 |
基础医学 | 234篇 |
口腔科学 | 11篇 |
临床医学 | 111篇 |
内科学 | 291篇 |
皮肤病学 | 15篇 |
神经病学 | 105篇 |
特种医学 | 39篇 |
外科学 | 92篇 |
综合类 | 7篇 |
预防医学 | 56篇 |
眼科学 | 25篇 |
药学 | 85篇 |
中国医学 | 5篇 |
肿瘤学 | 67篇 |
出版年
2024年 | 6篇 |
2023年 | 12篇 |
2022年 | 52篇 |
2021年 | 56篇 |
2020年 | 19篇 |
2019年 | 25篇 |
2018年 | 29篇 |
2017年 | 11篇 |
2016年 | 16篇 |
2015年 | 29篇 |
2014年 | 35篇 |
2013年 | 55篇 |
2012年 | 77篇 |
2011年 | 91篇 |
2010年 | 58篇 |
2009年 | 41篇 |
2008年 | 73篇 |
2007年 | 57篇 |
2006年 | 55篇 |
2005年 | 60篇 |
2004年 | 60篇 |
2003年 | 51篇 |
2002年 | 45篇 |
2001年 | 5篇 |
2000年 | 11篇 |
1999年 | 13篇 |
1998年 | 12篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 9篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 8篇 |
1986年 | 5篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1973年 | 6篇 |
1972年 | 5篇 |
1971年 | 3篇 |
1970年 | 6篇 |
排序方式: 共有1176条查询结果,搜索用时 15 毫秒
1.
Torrado M Trivedi R Zinovieva R Karavanova I Tomarev SI 《Human molecular genetics》2002,11(11):1291-1301
Mutations in the MYOC gene may lead to juvenile open-angle glaucoma with high intraocular pressure, and are detected in about 4% of people with adult onset glaucoma. Most of these mutations are found in the third exon of the gene encoding the olfactomedin-like domain located at the C terminus of the protein. Another olfactomedin-related protein, known as noelin or pancortin, is involved in the generation of neural crest cells. Here we describe the identification of a novel olfactomedin-related gene, named optimedin, located on chromosome 1p21 in humans. Optimedin and noelin are both expressed in brain and retina. However, unlike noelin, rat optimedin is also highly expressed in the epithelial cells of the iris and the ciliary body in close proximity to the sites of Myoc expression. In the human eye, optimedin is expressed in the retina and the trabecular meshwork. Both optimedin and myocilin are localized in Golgi and are secreted proteins. The presence of mutant myocilin interferes with secretion of optimedin in transfected cells. Optimedin and myocilin interact with each other in vitro as judged by the GST pulldown, co-immunoprecipitation and far-western binding assays. The C-terminal olfactomedin domains are essential for interaction between optimedin and myocilin, while the N-terminal domains of both proteins are involved in the formation of protein homodimers. We suggest that optimedin may be a candidate gene for disorders involving the anterior segment of the eye and the retina. 相似文献
2.
Martin Pdný Jan Lokaj Miroslava Novotn Stanislav ev
ík 《Macromolecular chemistry and physics.》1989,190(9):2229-2234
Interactions between the carbonyl and amino groups in copolymers of 2-dimethylaminoethyl methacrylate with N-phenylmaleimide are reported. The existence of interactions ensues from potentiometric measurements and UV-VIS spectra. Interactions in these copolymers result in the formation of energetically very advantageous chromophores, reflected in an intense red colour of the substances obtained. 相似文献
3.
A social-psychological perspective on successful community control of high blood pressure: A review 总被引:1,自引:0,他引:1
Stanislav V. Kasl 《Journal of behavioral medicine》1978,1(4):347-381
This review brings together studies dealing with factors that affect participation in screening, referral, and treatment for high blood pressure (HBP). Community-based screening programs are examined first, in order to describe the changing and the current distribution of hypertensives as unaware, untreated, treated but uncontrolled, and controlled by treatment. Factors influencing this distribution are examined. Next, data on referral, acceptance of treatment, and staying in treatment are discussed, with a special reference to intervention studies. The review then brings in the broader social science literature on the psychosocial dynamics of health-maintaining and risk-reducing behaviors. The article concludes with an interpretive summary and some suggestions for further action. 相似文献
4.
Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density. 相似文献
5.
Galina V. Kurlyandskaya Luis Lezama Anna A. Pasynkova Stanislav O. Volchkov Vera A. Lukshina Aitor Larraaga Natalia V. Dmitrieva Anastasia V. Timofeeva Iaki Orue 《Materials》2022,15(12)
The ferromagnetic resonance (FMR) in the frequency range of 0.5 to 12.5 GHz has been investigated as a function of external magnetic field for rapidly quenched Fe3Co67Cr3Si15B12 amorphous ribbons with different features of the effective magnetic anisotropy. Three states of the ribbons were considered: as-quenched without any treatment; after relaxation annealing without stress at the temperature of 350 °C during 1 h; and after annealing under specific stress of 230 MPa at the temperature of 350 °C during 1 h. For FMR measurements, we adapted a technique previously proposed and tested for the case of microwires. Here, amorphous ribbons were studied using the sample holder based on a commercial SMA connector. On the basis of the measurements of the reflection coefficient S11, the total impedance including its real and imaginary components was determined to be in the frequency range of 0.5 to 12.5 GHz. In order to confirm the validity of the proposed technique, FMR was also measured by the certified cavity perturbation technique using a commercial Bruker spectrometer operating at X-band frequency of 9.39 GHz. As part of the characterization of the ribbons used for microwave measurements, comparative analysis was performed of X-ray diffraction, optical microscopy, transmission electron microscopy, inductive magnetic hysteresis loops, vibrating sample magnetometry, magneto-optical Kerr effect (including magnetic domains) and magnetoimpedance data for of all samples. 相似文献
6.
Stanislav Koulchitsky Benjamin De Backer Etienne Quertemont Corinne Charlier Vincent Seutin 《Neuropsychopharmacology》2012,37(7):1559-1571
Cocaine (benzoylmethylecgonine), a natural alkaloid, is a powerful psychostimulant and a highly addictive drug. Unfortunately, the relationships between its behavioral and electrophysiological effects are not clear. We investigated the effects of cocaine on the firing of midbrain dopaminergic (DA) neurons, both in anesthetized and awake rats, using pre-implanted multielectrode arrays and a recently developed telemetric recording system. In anesthetized animals, cocaine (10 mg/kg, intraperitoneally) produced a general decrease of the firing rate and bursting of DA neurons, sometimes preceded by a transient increase in both parameters, as previously reported by others. In awake rats, however, injection of cocaine led to a very different pattern of changes in firing. A decrease in firing rate and bursting was observed in only 14% of DA neurons. Most of the other DA neurons underwent increases in firing rate and bursting: these changes were correlated with locomotor activity in 52% of the neurons, but were uncorrelated in 29% of them. Drug concentration measurements indicated that the observed differences between the two conditions did not have a pharmacokinetic origin. Taken together, our results demonstrate that cocaine injection differentially affects the electrical activity of DA neurons in awake and anesthetized states. The observed increases in neuronal activity may in part reflect the cocaine-induced synaptic potentiation found ex vivo in these neurons. Our observations also show that electrophysiological recordings in awake animals can uncover drug effects, which are masked by general anesthesia. 相似文献
7.
8.
S Popelka R Hromádka P Vav Ík V Barták S Popelka A Sosna 《BMC musculoskeletal disorders》2012,13(1):148
ABSTRACT: BACKGROUND: Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability. METHODS: The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray. RESULTS: Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3 %) in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9 %). CONCLUSION: The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility. 相似文献
9.
Adolescent varicocele: association with somatometric parameters 总被引:2,自引:0,他引:2
INTRODUCTION: The developmental changes that occur as a result of puberty have been hypothesized to be important causes of varicocele. Various somatometric parameters were known to affect the occurrence of varicocele during the growth period. We conducted this study in order to examine these relationships and to determine the incidence of varicocele in adolescent males. PATIENTS AND METHODS: We evaluated 1,200 healthy males aged 0-19 years for varicocele and correlated it with the following somatometric parameters: age, height, body mass index (BMI), pubic hair distribution, penile length and testicular volume. RESULTS: Adolescent varicocele was found in 5.6% of the participants. The 13- to 19-year age-group had the highest incidence of varicocele (10.5%). Logistic regression analysis showed that the incidence was positively correlated with age, height and penile length (odds ratio 1.61, 1.04 and 1.37, respectively) and negatively correlated with left testicular volume, BMI and pubic hair distribution (odds ratio 0.87, 0.87 and 0.47, respectively). CONCLUSION: Varicocele was more prevalent in tall boys with a lower BMI, who had quickly progressed through puberty. Our observations suggest that varicocele is associated with various somatometric parameters. 相似文献
10.
Alexandru Hanganu Stanislav A. Groppa Günther Deuschl Hartwig Siebner Friederike Moeller Michael Siniatchkin Ulrich Stephani Sergiu Groppa 《Brain topography》2015,28(5):702-709
Photoparoxysmal response (PPR) is an EEG trait of spike and spike-wave discharges in response to photic stimulation that is closely linked to idiopathic generalized epilepsy (IGE). In our previous studies we showed that PPR is associated with functional alterations in the occipital and frontal cortices. The aim of the present study was to determine structural changes associated with PPR. For this purpose we analysed the cortical thickness as derived from T1 MRI images in PPR-positive-subjects (n = 12; 15.5 ± 8.6 years; 4 males), PPR-positive-IGE-patients (n = 12; 14.9 ± 2.7 years; 4 males) and compared these groups with a group of PPR-negative-healthy-controls (HC, n = 17; 15.3 ± 3.6 years; 6 males). Our results revealed an increase of cortical thickness in the occipital, frontal and parietal cortices bilaterally in PPR-positive-subjects in comparison to HC. Moreover PPR-positive-subjects presented a significant decrease of cortical thickness in the temporal cortex in the same group contrast. IGE patients exhibited lower cortical thickness in the temporal lobe bilaterally and in the right paracentral region in comparison to PPR-positive-subjects. Our study demonstrates structural changes in the occipital lobe, frontoparietal regions and temporal lobe, which also show functional changes associated with PPR. Patients with epilepsy present changes in the temporal lobe and supplementary motor area. 相似文献