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排序方式: 共有3102条查询结果,搜索用时 31 毫秒
31.
Anke Goldhahn Thomas Schrom Alexander Berghaus Albrecht Krause Gernot Duncker 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,23(2):494-497
Lid-loading with precious metals, described by Illig in 1958, has become increasingly important. Because of its good functional
and cosmetic results this method is superior to tarsorrhaphy. Furthermore, lid-loading can be combined with additional surgical
techniques to achieve more dynamic lid-closure. In a prospective study we examined the results after lid-loading and discuss
postoperative changes of the cornea. 相似文献
32.
B. Niggemann A. Müller Anke Nolte N. Schnoy U. Wahn 《European journal of pediatrics》1992,151(1):73-75
A 7-year-old Turkish boy had suffered from chronic coughing from early childhood. Severe bronchiectasis in the right lung was confirmed by bronchography. Ciliary beat frequency determined in a bronchial mucosal biopsy was markedly decreased (5.7 Hz). Electron microscopy revealed cilia with a length of 15 m. No structural abnormality was found. A possible link between the abnormally long, slow beating cilia and the clinical symptoms is discussed. 相似文献
33.
Stefan Holdenrieder Jutta Stief Albrecht Bergner Fernando Gamarra Anke Mitlewski Dorothea Nagel Rudolph M Huber Petra Stieber 《Tumour biology》2004,25(5-6):321-326
Nucleosomes, which are typical cell death products, are elevated in the serum of cancer patients and are known to rapidly increase during radiotherapy. As both normal and malignant cells are damaged by irradiation, we investigated to which extent both cell types contribute to the release of nucleosomes. We cultured monolayers of normal bronchoepithelial lung cells (BEAS-2B, n = 18) and epithelial lung cancer cells (EPLC, n = 18), exposed them to various radiation doses (0, 10 and 30 Gy) and observed them for 5 days. Culture medium was changed every 24 h. Subsequently, nucleosomes were determined in the supernatant by the Cell Death Detection-ELISA(plus) (Roche Diagnostics). Additionally, the cell number was estimated after harvesting the cells in a second preparation. After 5 days, the cell number of BEAS-2B cultures in the irradiated groups (10 Gy: median 0.03 x 10(6) cells/culture, range 0.02-0.08 x 10(6) cells/culture; 30 Gy: median 0.08 x 10(6) cells/culture, range 0.02-0.14 x 10(6) cells/culture) decreased significantly (10 Gy: p = 0.005; 30 Gy p = 0.005; Wilcoxon test) compared to the non-irradiated control group (median 4.81 x 10(6) cells/culture, range 1.50-9.54 x 10(6) cells/culture). Consistently, nucleosomes remained low in the supernatant of non-irradiated BEAS-2B. However, at 10 Gy, BEAS-2B showed a considerably increasing release of nucleosomes, with a maximum at 72 h (before irradiation: 0.24 x 10(3) arbitrary units, AU, range 0.13-4.09 x 10(3) AU, and after 72 h: 1.94 x 10(3) AU, range 0.11-5.70 x 10(3) AU). At 30 Gy, the release was even stronger, reaching the maximum earlier (at 48 h, 11.09 x 10(3) AU, range 6.89-18.28 x 10(3) AU). In non-irradiated EPLC, nucleosomes constantly increased slightly. At 10 Gy, we observed a considerably higher release of nucleosomes in EPLC, with a maximum at 72 h (before irradiation: 2.79 x 10(3) AU, range 2.42-3.80 x 10(3) AU, and after 72 h: 7.16 x 10(3) AU, range 4.30-16.20 x 10(3) AU), which was more than 3.5 times higher than in BEAS-2B. At 30 Gy, the maximum (6.22 x 10(3) AU, range 5.13-9.71 x 10(3) AU) was observed already after 24 h. These results indicate that normal bronchoepithelial and malignant lung cancer cells contribute to the release of nucleosomes during irradiation in a dose- and time-dependent manner with cancer cells having a stronger impact at low doses. 相似文献
34.
Cornelis P. J. Vendrik Anne Marie J. Fichtinger-Schepman Wilhelmina C. M. van Dijk-Knijnenburg W. H. de Jong Anke C. E. van der Minnen Gerard de Groot Geert Frits Berends P. A. Steerenberg 《Cancer chemotherapy and pharmacology》1997,39(6):479-485
An IgM immunocytoma cell line sensitive to cis-diamminedichloroplatinum(II) (CDDP) and a subline with acquired resistance were grown in LOU/M rats. In a previous study
with such rats that had been treated with a high dose of CDDP (10 mg/kg) the tumors did not show differences in cellular platinum
content or DNA-adduct levels, either immediately after treatment or 24 h later. Recently, this high dose was found to overcome
resistance. Therefore, the study was repeated with a 10-fold lower dose (1 mg/kg, i.v.). At 1 and 24 h after treatment, tumor
and kidney tissue were assayed for cellular platinum (atomic absorption spectroscopy, AAS) and DNA platination (immunochemical
detection of the four CDDP-DNA adducts). The results were compared with previous data. All tissues showed a linear response
to dose with regard to platinum uptake as well as adduct formation, with no quantitative difference being seen between the
tumors. Also the relative occurrence of the four adducts was very similar. Between 1 and 24 h, in tumors a substantial decrease
occurred in both platinum content and adduct level; the kidneys showed little reduction, if any. At the lower CDDP dose a
somewhat larger loss of platinum and removal of DNA adducts was observed for the resistant tumor, but these differences could
be explained by “dilution”, as this tumor continues to grow after low-dose treatment (about 20% within 24 h). Since the strong
difference observed between the tumors in sensitivity to CDDP cannot be attributed to differences in CDDP uptake, efficiency
of adduct formation, or repair capability, other mechanisms are held responsible.
Received 10 August 1995 / Accepted: 14 August 1996 相似文献
35.
P53 mutation analysis of colorectal liver metastases: relation to actual survival, angiogenic status, and p53 overexpression. 总被引:4,自引:0,他引:4
Koert P de Jong Annette S H Gouw Paul M J G Peeters Marian Bulthuis Lorian Menkema Robert J Porte Maarten J H Slooff Harry van Goor Anke van den Berg 《Clinical cancer research》2005,11(11):4067-4073
PURPOSE: To correlate TP53 mutations with angiogenic status of the tumor and prognosis after liver surgery in patients with colorectal liver metastases and to correlate immunohistochemical staining of p53 protein with TP53 gene mutations. EXPERIMENTAL DESIGN: Tumors of 44 patients with surgically treated colorectal liver metastases were analyzed for (a) TP53 mutations using denaturing gradient gel electrophoresis followed by sequencing, (b) microvessel density using the hot spot overlap technique, (c) apoptotic rate in tumor cells and endothelial cells of tumor microvessels using double immunostaining for anti-cleaved caspase 3 and anti-CD34, and (d) expression of p53 protein using immunohistochemistry. RESULTS: TP53 mutations were detected in 36% of the metastases and occurred more frequently in liver metastases from left-sided colon tumors than from right-sided colon tumors (P = 0.04). In metastases with TP53 mutations, microvessel density was higher compared with tumors with wild-type p53. Endothelial cell apoptosis was not different in tumor microvessels from TP53-mutated versus nonmutated tumors. The 5-year actual survival was not influenced by TP53 mutational status, microvessel density, or endothelial cell apoptotic rate of the tumors. Based on immunohistochemical p53 overexpression, the positive and negative predictive values of TP53 mutations were 61% and 82%. CONCLUSIONS: In patients with surgically treated colorectal liver metastases, TP53 mutations and angiogenic status did not influence prognosis. Immunohistochemistry is not a reliable technique for detecting TP53 mutations. 相似文献
36.
37.
Miranda Wolpert Andrew J.B. Fugard Jessica Deighton Anke Görzig 《Child and Adolescent Mental Health》2012,17(3):129-130
This brief commentary article considers the implications of intensive outcome monitoring which is central to children and young people's Improving Access to Psychological Therapies (CYP IAPT) in England and Wales. Services are being provided with a range of free software solutions to enable data collection, and guidance on interpretation of the measures, but there will still be some burden of data entry and collation for already overstretched services. It may be that the utility of the feedback will go some way to offset the sense of burden but this remains to be seen. Whether commissioners and others will rise to the challenge of supporting this aspect may prove crucial to the success or otherwise of such intensive ROM use. Many aspects of the CYP IAPT approach are new and whilst drawing on experience from earlier pilots of session by session monitoring in CAMHS both in the UK and abroad, and from Adult IAPT, there is likely to be much for us to learn. Time will tell whether the approach helps to improve the care children and young people receive but we are cautiously optimistic. 相似文献
38.
39.
Anke Augspach Joachim H. List Philipp Wolf Heike Bielek Carsten Schwan Ursula Els?sser-Beile Klaus Aktories Gudula Schmidt 《Toxins》2013,5(11):2241-2257
Prostate cancer is the most common malignancy, accounting for about 25% of all incident cases among men in industrialized countries. The human androgen-dependent prostate cancer cell line LNCaP, which is derived from a metastatic lesion of human prostatic adenocarcinoma, is frequently used to study prostate cancer associated signaling pathways in vitro. Recently it was described that Rho GTPase activation in these cells leads to apoptotic responses. We used the bacterial toxins CNFy and CNF1, which specifically and directly activate Rho GTPases by deamidation of a single glutamine. We asked whether these Rho activators could induce apoptosis in LNCaP cells. Our results indicate that RhoA activation, induced by CNFy, does lead to intrinsic apoptosis of the cells. Analysis of the underlying signaling pathway reveals that apoptosis induction requires the activity of Rho kinase (ROCK) and myosin activation, an apoptotic pathway previously identified in cancer stem cells. 相似文献
40.
Quantification of magnetic resonance spectroscopy signals using the phantom replacement method requires an adequate correction of differences between the acquisition of the reference signal in the phantom and the measurement in vivo. Applying the principle of reciprocity, sensitivity differences can be corrected at low field strength by measuring the RF transmitter gain needed to obtain a certain flip angle in the measured volume. However, at higher field strength the transmit sensitivity may vary from the reception sensitivity, which leads to wrongly estimated concentrations. To address this issue, a quantification approach based on the principle of reciprocity for use at 3T is proposed and validated thoroughly. In this approach, the RF transmitter gain is determined automatically using a volume‐selective power optimization and complemented with information from relative reception sensitivity maps derived from contrast‐minimized images to correct differences in transmission and reception sensitivity. In this way, a reliable measure of the local sensitivity was obtained. The proposed method is used to derive in vivo concentrations of brain metabolites and tissue water in two studies with different coil sets in a total of 40 healthy volunteers. Resulting molar concentrations are compared with results using internal water referencing (IWR) and Electric REference To access In vivo Concentrations (ERETIC). With the proposed method, changes in coil loading and regional sensitivity due to B1 inhomogeneities are successfully corrected, as demonstrated in phantom and in vivo measurements. For the tissue water content, coefficients of variation between 2% and 3.5% were obtained (0.6–1.4% in a single subject). The coefficients of variation of the three major metabolites ranged from 3.4–14.5%. In general, the derived concentrations agree well with values estimated with IWR. Hence, the presented method is a valuable alternative for IWR, without the need for additional hardware such as ERETIC and with potential advantages in diseased tissue. 相似文献