全文获取类型
收费全文 | 845篇 |
免费 | 58篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 75篇 |
妇产科学 | 3篇 |
基础医学 | 65篇 |
口腔科学 | 11篇 |
临床医学 | 86篇 |
内科学 | 85篇 |
皮肤病学 | 28篇 |
神经病学 | 63篇 |
特种医学 | 70篇 |
外科学 | 232篇 |
综合类 | 14篇 |
预防医学 | 37篇 |
眼科学 | 8篇 |
药学 | 58篇 |
肿瘤学 | 39篇 |
出版年
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 26篇 |
2020年 | 9篇 |
2019年 | 15篇 |
2018年 | 25篇 |
2017年 | 13篇 |
2016年 | 29篇 |
2015年 | 30篇 |
2014年 | 29篇 |
2013年 | 29篇 |
2012年 | 39篇 |
2011年 | 49篇 |
2010年 | 26篇 |
2009年 | 25篇 |
2008年 | 49篇 |
2007年 | 58篇 |
2006年 | 50篇 |
2005年 | 58篇 |
2004年 | 62篇 |
2003年 | 41篇 |
2002年 | 32篇 |
2001年 | 12篇 |
2000年 | 14篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 9篇 |
1996年 | 11篇 |
1995年 | 5篇 |
1994年 | 12篇 |
1993年 | 4篇 |
1992年 | 13篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 6篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1985年 | 7篇 |
1984年 | 5篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1975年 | 3篇 |
1973年 | 2篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1963年 | 2篇 |
1941年 | 2篇 |
1940年 | 2篇 |
1937年 | 2篇 |
排序方式: 共有904条查询结果,搜索用时 31 毫秒
1.
Tobias Kisch Julia Maria Klemens Katharina Hofmann Eirini Liodaki Matthias Gierloff Dirk Moellmeier Felix Stang Peter Mailaender Jens Habermann Matthias Brandenburger 《Medicine》2015,94(41)
The regrowth of amputated digit tips represents a unique regenerative healing in mammals with subcutaneous volume regrowth, restoration of dactylogram, and suppression of scar formation. Although factor analysis in amphibians and even in mice is easy to obtain, safety of harvesting biomaterial from human digit tip amputations for analysis has not yet been described.The aim of this study was to evaluate if recovering wound exudate does hamper clinical outcome or influence microbiologic or inflammation status.A predefined cohort of 18 patients with fresh digit tip amputations was randomly assigned to receive standard therapy (debridement, occlusive dressing) with (n = 9) or without (n = 9) collection of the whole wound exudate in every dressing change. Primary endpoint (lengthening) and secondary endpoints (regeneration of dactylogram, nail bed and bone healing, time to complete wound closure, scar formation, 2-point discrimination, microbiologic analysis, inflammatory factors interleukin (IL)-1α, tumor necrosis factor-α, IL-4, and IL-6) were determined by an independent, blinded observer.Patients’ characteristics showed no significant differences between the groups. All patients completed the study to the end of 3 months follow-up. Exudate collection did not influence primary and secondary endpoints. Furthermore, positive microbiologic findings as well as pus- and necrosis-like appearance neither impaired tissue restoration nor influenced inflammatory factor release.Here, the authors developed an easy and safe protocol for harvesting wound exudate from human digit tip amputations. For the first time, it was shown that harvesting does not impair regenerative healing. Using this method, further studies can be conducted to analyze regeneration associated factors in the human digit tip.DRKS.de Identifier: DRKS00006882 (UTN: U1111-1166-5723). 相似文献
2.
Lutz Fritsche Klemens Budde Hans-Hellmut Neumayer 《Nephrology, dialysis, transplantation》2003,18(3):621-2; author reply 622
Sir, The paper by Zeier and Ritz in the April 2002 issue of NDT [1]is a good reminder of the importance of evaluation and selectionof kidney transplant candidates. Also, this paper clearly demonstratesthe persisting lack of clinical evidence in this field, whichhas considerable impact on large numbers of end-stage renaldisease patients. We have previously demonstrated the unexplained variations inthe evaluation 相似文献
3.
Markus Dietlein Klemens Scheidhauer Eberhard Voth Peter Theissen Harald Schicha 《European journal of nuclear medicine and molecular imaging》1997,24(11):1342-1348
Metastases of differentiated thyroid cancer may show different uptake patterns for fluorine-18 fluorodeoxyglucose and [131I]NaI. FDG positron emission tomography (PET), iodine-131 whole-body scintigraphy (131I WBS) and magnetic resonance imaging were performed in 58 unselected patients, and spiral computed tomography (CT) of the
lung in 25 patients. Thirty-eight patients presented with papillary carcinomas, 15 patients with follicular carcinomas and
five patients with variants of follicular carcinoma. Primary tumour stage (pT) was pT1 in 3, pT2 in 19, pT3 in 11 and pT4
in 25 cases. For the detection of metastases, FDG PET was found to have a sensitivity of 50%, 131I WBS a sensitivity of 61%, and the two methods combined a sensitivity of 86%. When FDG PET was limited to patients with elevated
thyroglobulin (Tg) levels and negative 131I WBS, the sensitivity of this algorithm was 82%. Of the 21 patients with lymph node metastases, seven presented with FDG
uptake but no iodine uptake. In four of them, a second FDG hot spot appeared in a lymph node metastasis of normal size. Five
of the seven patients underwent surgery. None of the eight patients with pulmonary metastases smaller than 1 cm exhibited
FDG uptake, while five of them had iodine uptake. All had positive results on spiral CT. In conclusion, FDG PET cannot be
substituted for 131I WBS. If the Tg level is elevated and 131I WBS is negative, FDG PET can be used to detect lymph node metastases and complements anatomical imaging. A spiral CT of
the lung is useful to exclude pulmonary metastases before planning a dissection of iodine-negative lymph node metastases.
Received 2 May and in revised form 8 July 1997 相似文献
4.
Carla M Stehr Tiffany L Linbo John P Incardona Nathaniel L Scholz 《Toxicological sciences》2006,92(1):270-278
Fipronil is a phenylpyrazole insecticide designed to selectively inhibit insect gamma-aminobutyric acid (GABA) receptors. Although fipronil is often used in or near aquatic environments, few studies have assessed the effects of this neurotoxicant on aquatic vertebrates at sensitive life stages. We explored the toxicological effects of fipronil on embryos and larvae using the zebrafish (Danio rerio) experimental model system. Embryos exposed to fipronil at nominal concentrations at or above 0.7 microM (333 mug/l) displayed notochord degeneration, shortening along the rostral-caudal body axis, and ineffective tail flips and uncoordinated muscle contractions along the body axis in response to touch. This phenotype closely resembles zebrafish locomotor mutants of the accordion class and is consistent with loss of reciprocal inhibitory neurotransmission by glycinergic commissural interneurons in the spinal cord. Consistent with the hypothesis that notochord degeneration may be due to abnormal mechanical stress from muscle tetany, the expression patterns of gene and protein markers specific to notochord development were unaffected by fipronil. Moreover, the degenerative effects of fipronil (1.1 microM) were reversed by coexposure to the sodium channel blocker MS-222 (0.6mM). The notochord effects of fipronil were phenocopied by exposure to 70 microM strychnine, a glycinergic receptor antagonist. In contrast, exposure to gabazine, a potent vertebrate GABA(A) antagonist, resulted in a hyperactive touch response but did not cause notochord degeneration. Although specifically developed to target insect GABA receptors with low vertebrate toxicity, our results suggest that fipronil impairs the development of spinal locomotor pathways in fish by inhibiting a structurally related glycine receptor subtype. This represents an unanticipated and potentially novel mechanism for fipronil toxicity in vertebrates. 相似文献
5.
Lutz Fritsche Gunilla Einecke Franca Fleiner Duska Dragun Hans-Hellmut Neumayer Klemens Budde 《American journal of transplantation》2004,4(5):738-743
The reporting quality of publications of clinical trials can affect the quality of clinical decision-making. We systematically assessed the quality of publications of large multicenter trials evaluating immunosuppressive regimens in de novo kidney transplantation. Study quality, reporting quality and accessibility of the results of 63 publications were assessed independently by three blinded investigators using an instrument combining the Jadad scale with a list of reporting quality items. Study quality was rated with an average of only 2.3 (range 1-5) on the Jadad scale. Unblinded studies were reported in 68.3% of publications and follow-up longer than 12 months was reported for only 13 out of 50 studies. The reviewed publications fulfilled an average of 69.1% of the reporting quality criteria. Fifty-four percent of publications did not report both treated and biopsy-proven rejections. Whether reported graft survival was censored for death could not be determined for 27% of publications. Only a few publications gave confidence intervals (CIs) or stated whether additional analyses were pre-specified. Even the largest trials of immunosuppression in kidney transplantation show considerable quality deficits in their design and publication. Additional efforts are required of investigators, editors and sponsors to achieve maximum study and reporting quality. 相似文献
6.
Manfred L'Age Johanna Stehr Peter Wahl 《Journal of molecular medicine (Berlin, Germany)》1963,41(13):659-662
Zusammenfassung Das Verhalten der Unveresterten Fettsäuren an Gesunden und Diabetikern und am epididymalen Fettgewebe der Ratte unter N1-n-Butylbiguanid wurde untersucht. Normalpersonen mit und ohne Biguanid reagieren bei Blutzuckerabfall mit einem Anstieg der UFS, der unter Biguanid signifikant höher ist. Diabetiker zeigen einen geringfügigen Abfall der UFS nach Biguanid. Unter Biguanidkonzentrationen, die der therapeutischen Serumkonzentration entsprechen (5/ml), werden vom Fettgewebe in Gegenwart von Glucose vermehrt UFS utilisiert. Bei hohen Konzentrationen (100 bis 1000/ml) tritt ein Wirkungsumschlag ein, die Fettsäureutilisation wird gehemmt.Teile dieser Arbeit sind in den Dissertationen vonM. L'age undJ. Stehr enthalten. 相似文献
7.
Frei K Szuhai K Lucas T Weipoltshammer K Schöfer C Ramsebner R Baumgartner WD Raap AK Bittner R Wachtler FJ Kirschhofer K 《European journal of human genetics : EJHG》2002,10(7):427-432
Mutations in the connexin 26 (Cx26) gene (GJB2) are associated with autosomal nonsyndromic sensorineural hearing loss. This study describes mutations in the Cx26 gene in cases of familial and sporadic hearing loss (HL) by gene sequencing and identifies the allelic frequency of the most common mutation leading to HL (35delG) in the population of eastern Austria. For this purpose we have developed and applied a molecular beacon based real-time mutation detection assay. Mutation frequencies in the Cx26 gene of individuals from affected families (14 out of 46) and sporadic cases (11 out of 40) were 30.4% and 27.5%, respectively. In addition to known disease related alterations, a novel mutation 262 G-->T (A88S) was also identified. 35delG accounted for almost 77% of all Cx26 mutations detected and displayed an allelic frequency in the normal hearing population of 1.7% (2 out of 120). The high prevalence of the 35delG mutation in eastern Austria would therefore allow screening of individuals and family members with Cx26 dependent deafness by a highly specific and semi-automated method. 相似文献
8.
Expression of platelet-derived growth factor-AA is associated with tumor progression in osteosarcoma. 总被引:3,自引:0,他引:3
Irene Sulzbacher Peter Birner Klemens Trieb Margit Tr?xler Susanna Lang Andreas Chott 《Modern pathology》2003,16(1):66-71
Platelet-derived growth factors are secreted by mesenchymal cells. The homodimer platelet-derived growth factor-AA especially stimulates bone cells through interaction with the platelet-derived growth factor-alpha receptor homodimer. In this study we wanted to determine the expression of the receptor and its ligand in human osteosarcomas and to correlate the expression of platelet-derived growth factor-AA and -alpha receptor with clinicopathological parameters. Fifty-seven osteosarcomas were immunohistochemically analyzed for expression of platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor. Spearman's correlation coefficient revealed a strong correlation between the expression of platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor (r = 0.867). No differences were observed relative to gender, age, tumor stage, tumor location, and response to neoadjuvant chemotherapy between high or low platelet-derived growth factor-AA and platelet-derived growth factor-alpha receptor expression. High platelet-derived growth factor-AA expression correlated with tumor progression in univariate analysis (P = .0415; log-rank test), whereas platelet-derived growth factor-alpha receptor expression showed a trend toward a shorter disease-free survival, which failed to reach significance (P = .0627, log-rank test). In multivariate analysis, platelet-derived growth factor-AA expression remained a significant independent predictor of tumor progression (P = .021, Cox regression). Immunohistochemical analysis of platelet-derived growth factor-AA expression in osteosarcoma may be a useful marker of prognosis and may be considered as a possible target for novel therapeutic strategies. 相似文献
9.
In order to investigate the possibility of isolating greater amounts of the antimalarial compound artemisinin (quinghaosu), plants of ARTEMISIA ANNUA were cultivated and analysed at different stages of development. We found the highest content just before flowering. It was also possible to correlate development of the plants with the maximum content of artemisinin. ARTEMISIA ANNUA plants cultivated from various other sources were also examine for artemisinin content. According to our results, none of these plants contained sufficient amounts of artemisinin to justify an isolation on a technical scale. Furthermore other Artemisia species were tested. We found artemisinin in only one other species. To possibly increase the amount of artemisinin during the growth period of the plant, we tested two hormone-type growth regulators on A. ANNUA strain 811. The results showed that one of them, chlormequat, was able to increase the artemisinin content by 30% over untreated plants. We also found some slight effects of the growth regulators on morphological criteria of glandular trichomes. 相似文献
10.