全文获取类型
收费全文 | 1041篇 |
免费 | 33篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 19篇 |
妇产科学 | 64篇 |
基础医学 | 167篇 |
口腔科学 | 9篇 |
临床医学 | 57篇 |
内科学 | 252篇 |
皮肤病学 | 12篇 |
神经病学 | 87篇 |
特种医学 | 21篇 |
外科学 | 137篇 |
综合类 | 4篇 |
预防医学 | 63篇 |
眼科学 | 3篇 |
药学 | 93篇 |
中国医学 | 1篇 |
肿瘤学 | 79篇 |
出版年
2022年 | 26篇 |
2021年 | 24篇 |
2020年 | 18篇 |
2019年 | 14篇 |
2018年 | 19篇 |
2017年 | 6篇 |
2016年 | 7篇 |
2015年 | 20篇 |
2014年 | 25篇 |
2013年 | 38篇 |
2012年 | 41篇 |
2011年 | 54篇 |
2010年 | 26篇 |
2009年 | 33篇 |
2008年 | 40篇 |
2007年 | 74篇 |
2006年 | 59篇 |
2005年 | 73篇 |
2004年 | 65篇 |
2003年 | 55篇 |
2002年 | 57篇 |
2001年 | 17篇 |
2000年 | 19篇 |
1999年 | 17篇 |
1998年 | 11篇 |
1997年 | 23篇 |
1996年 | 13篇 |
1995年 | 17篇 |
1994年 | 9篇 |
1993年 | 4篇 |
1992年 | 11篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 10篇 |
1988年 | 13篇 |
1987年 | 8篇 |
1986年 | 18篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1976年 | 6篇 |
1975年 | 3篇 |
1974年 | 8篇 |
1973年 | 7篇 |
1971年 | 3篇 |
1967年 | 6篇 |
1965年 | 9篇 |
排序方式: 共有1086条查询结果,搜索用时 15 毫秒
1.
Agata Cieślik-Bielecka Paweł Reichert Rafał Skowroński Tomasz Bielecki 《Platelets》2019,30(6):728-736
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity. 相似文献
2.
3.
The paper presents the possibilities of applying the posterior thigh flap in the treatment of ischial pressure sores. Between 2000 and 2004 the flap was used in three cases treated in the Orthopaedics and Traumatology Department of the Medical Universtity in Bialystok. The indications, contraindications, operative technique and advantages of the posterior thigh flap are described. In all three cases the ischial bed sores healed well without recurrences. The posterior fasciocutaneous pedicled flap is a good method of treatment for not too extensive bed sores in the ischial region.This flap can be applied in recurrences found after primary bed sore treatment with another method. However the fasciocutaneous flap has a limited range of transposition as compared with cutaneous flaps. 相似文献
4.
5.
13C-NMR and the electron impact mass spectra of the β-carboline derivatives 1 – 18 were examined. The structure of the possible diastereomers is discussed. A quantitative relationship between the relative intensity of ions a in the mass spectra of 1 – 18 and the structure of substituents R was found. 相似文献
6.
Charles J. Coté Alfred L. Daniels Michelle Connolly Stanislaw K. Szyfelbein Charles D. Wickens 《Journal canadien d'anesthésie》1992,39(5):454-457
We undertook a prospective study of standard peripheral pulse oximetry versus a modified pulse oximeter probe applied to the tongue in order to determine the efficacy of this alternative monitoring site in children with thermal injuries. Ten patients with a mean age (± SD) of 7.5 ± 4.5 yr were studied on 15 occasions. The mean weight +- SD) was 31.4+- 13.7 kg and percent surface area burn (± SD) was 56+- 21%. A total of 1,992 min of anaesthesia time was monitored. Both sites functioned simultaneously 47% of the time; the lingual but not the peripheral site functioned 28% of the time and only the peripheral site and not the lingual functioned 22% of the time. Neither site functioned 3% of the time. The tongue oximeter provided 563 min more monitoring time than the peripheral sites. The tongue oximeter also functioned in children with peripheral vasoconstriction when the peripheral sensor failed and was less susceptible to electrocautery interference. The tongue oximeter is a reasonable adjunct but not a substitute for peripheral oximetry since its application is limited to paralyzed, intubated patients. 相似文献
7.
8.
Karl‐Jürgen Br Stanislaw Brehm Michael Karl Boettger Gerd Wagner Silke Boettger Heinrich Sauer 《European Journal of Pain》2006,10(5):467-471
An altered perception of pain has been described for several psychiatric disorders. To date the influence of adjustment disorders (AD) on pain perception has not been described. Here, we investigated perception of experimentally induced pain in 15 patients suffering from AD (subtype with depressive symptoms) and controls matched for age and sex. Thresholds and tolerances were assessed for thermal and electrical pain on both sides of the body. We found an overall increase of pain thresholds and tolerances in AD patients as compared to controls, predominately on the right side of the body. Analogue findings have been reported for pain perception in major depressive disorder (MDD). Of the data obtained, only thermal pain threshold on the right arm correlated with the severity of depressive symptoms. Although the underlying pathology is elusive it is likely that the mechanisms for reduced pain sensitivity are comparable in MDD and AD. 相似文献
9.
Long-term ultraviolet-light (UV) exposure of human skin epidermis is associated with an increased risk for the development of skin cancers, such as melanoma, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). UV radiation not only induces DNA damage in epidermal cells, it also interferes with skin homeostasis, which is maintained by a unique distribution pattern of apoptosis-inducing and -preventing molecules. If the DNA damage is not repaired or the damaged cells are not eliminated by apoptosis, the consequence can be cell transformation, uncontrolled proliferation and eventually skin tumor formation. An important "repair" gene is the p53 suppressor gene. Excessive UV exposure can mutate the p53 gene leading to the loss of its repair function and thus apoptosis resistance of the DNA-damaged cell. For BCC formation an additional pathway has been identified. Mutation of genes of the Hedgehog signaling pathway evokes the downregulation of apoptotic genes and upregulation of anti-apoptotic genes preventing the elimination of damaged cells. In addition, BCC and SCC strongly express the apoptosis-inducing Fas-ligand (FasL) which may help the tumor to escape the attack of immune effector cells. Silencing the genes involved in tumor formation by RNA interference might become a promising new approach to treat skin tumors. 相似文献
10.
Stanislaw Sosnowski Stanislaw Slomkowski Stanislaw Penczek Zbigniew Florjanczyk 《Macromolecular chemistry and physics.》1991,192(7):1457-1465
The synthesis of highly uniform (1,08 ≤ M w/M n ≤ 1,13) telechelic poly(ε-caprolactone) terminated at both ends with OH groups and its derivatization leading to poly(ε-caprolactone) with pyrene end-groups are described. The synthesis, carried out in THF at room temperature, involves initiation with (CH3CH2)2AlO(CH2CH2O)3Al(CH2CH3)2, leading to poly(ε-caprolactone) macromolecules growing at both ends. The active centers were deactivated with acetic acid, giving macromolecules with OH end-groups. Reaction of α,ω-dihydroxypoly(ε-caprolactone), HO-poly(εCL)-OH, with 4-(1-pyrenyl)butyryl chloride yields α,ω-di-1-pyrenylpoly(ε-caprolactone), Py-poly(εCL)-Py. Polymers are characterized by GPC, 1H NMR, and UV spectroscopies. The UV spectra of polymers with pyrene end-groups are compared with the UV spectra of the model compound. 相似文献