全文获取类型
收费全文 | 871篇 |
免费 | 37篇 |
国内免费 | 2篇 |
学科分类
医药卫生 | 910篇 |
出版年
2019年 | 8篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 22篇 |
2014年 | 19篇 |
2013年 | 26篇 |
2012年 | 28篇 |
2011年 | 37篇 |
2010年 | 18篇 |
2009年 | 19篇 |
2008年 | 36篇 |
2007年 | 45篇 |
2006年 | 43篇 |
2005年 | 26篇 |
2004年 | 16篇 |
2003年 | 17篇 |
2002年 | 31篇 |
2001年 | 16篇 |
2000年 | 15篇 |
1999年 | 14篇 |
1994年 | 7篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 7篇 |
1988年 | 11篇 |
1987年 | 9篇 |
1986年 | 7篇 |
1978年 | 7篇 |
1975年 | 9篇 |
1972年 | 9篇 |
1971年 | 9篇 |
1970年 | 9篇 |
1968年 | 8篇 |
1939年 | 12篇 |
1938年 | 19篇 |
1937年 | 17篇 |
1936年 | 7篇 |
1933年 | 9篇 |
1932年 | 10篇 |
1931年 | 11篇 |
1930年 | 23篇 |
1929年 | 17篇 |
1928年 | 17篇 |
1927年 | 18篇 |
1926年 | 13篇 |
1925年 | 19篇 |
1924年 | 17篇 |
1923年 | 15篇 |
1922年 | 19篇 |
排序方式: 共有910条查询结果,搜索用时 15 毫秒
1.
Epithelium-derived inhibitory factor in human bronchus 总被引:2,自引:0,他引:2
L B Fernandes J M Preuss J W Paterson R G Goldie 《European journal of pharmacology》1990,187(3):331-336
The potencies of histamine and methacholine were significantly increased by approximately 2- and 5-fold respectively in human non-diseased isolated bronchi on removal of the epithelium. In contrast, no increases in spasmogen potency were observed following epithelium removal in bronchi obtained from a sample of asthmatic human lung. The failure of epithelium removal to increase asthmatic bronchial sensitivity to histamine may have been due to a reduction in the release of an epithelium-derived inhibitory factor (EpDIF) resulting from disease-induced epithelial damage. A co-axial bioassay system in which endothelium-denuded rat aorta was used as the assay tissue was used to detect the release of a vasorelaxant EpDIF from human bronchial tissue. Histamine (100 microM) and methacholine (25 microM), in the presence of indomethacin (5 microM), reduced phenylephrine-induced tone in endothelium-denuded rat aorta in co-axial assemblies by 75 +/- 11 and 67 +/- 9% respectively. Removal of the bronchial epithelium abolished these responses, indicating that they were mediated by an EpDIF. It is possible that human airway smooth muscle is sensitive to this vasorelaxant EpDIF and that the absence of the source of this factor following epithelium removal caused the increases in sensitivity to spasmogens. Alternatively, the human bronchial epithelium may also release an EpDIF selective for airway smooth muscle. 相似文献
2.
Large-scale screening of nasal swabs for Bacillus anthracis: descriptive summary and discussion of the National Institutes of Health's experience 下载免费PDF全文
Kiratisin P Fukuda CD Wong A Stock F Preuss JC Ediger L Brahmbhatt TN Fischer SH Fedorko DP Witebsky FG Gill VJ 《Journal of clinical microbiology》2002,40(8):3012-3016
In October 2001, a letter containing a large number of anthrax spores was sent through the Brentwood post office in Washington, D.C., to a United States Senate office on Capitol Hill, resulting in contamination in both places. Several thousand people who worked at these sites were screened for spore exposure by collecting nasal swab samples. We describe here a screening protocol which we, as a level A laboratory, used on very short notice to process a large number of specimens (3,936 swabs) in order to report preliminary results as quickly as possible. Six isolates from our screening met preliminary criteria for Bacillus anthracis identification and were referred for definitive testing. Although none of the isolates was later confirmed to be B. anthracis, we studied these isolates further to define their biochemical characteristics and 16S rRNA sequences. Four of the six isolates were identified as Bacillus megaterium, one was identified as Bacillus cereus, and one was an unidentifiable Bacillus sp. Our results suggest that large-scale nasal-swab screening for potential exposure to anthrax spores, particularly if not done immediately postexposure, may not be very effective for detecting B. anthracis but may detect a number of Bacillus spp. that are phenotypically very similar to B. anthracis. 相似文献
3.
Nissum M Preuss D Harig A Lieberwirth U Betz C Neumann S Deravanessian E Bock M Wehmeier L Bonk T 《Psychiatric genetics》2002,12(2):109-117
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a powerful and widespread analytical tool in all fields of life science. Compared with other techniques, its high accuracy and sensitivity makes it a superior method, especially for the analysis of nucleic acids. Recent problems in the analysis of nucleic acids by MALDI-TOF MS can be solved using an automated MALDI-compatible sample-preparation system. Together with the reliable minisequencing assay, high-throughput genotyping of single nucleotide polymorphisms by MALDI-TOF MS is able to become a routine method in research, clinical genetics and diagnostics. 相似文献
4.
De BK Booth DD Magee PJ Moore ML Preuss TM Rose TA Roberts WL 《Therapeutic drug monitoring》1999,21(1):123-128
The analytic performance of two automated nonpretreatment digoxin methods, AxSYM Digoxin II and Vitros digoxin immunoassays, was assessed. Both assays had analytic sensitivities of less than 0.2 microg/L, were linear from digoxin concentrations of 0.5 to 4.0 microg/L, and showed acceptable precision, with a maximum total coefficient of variation (CV) of 8.9% and 6.4% for the AxSYM and Vitros, respectively. Comparison of the two methods using samples from patients receiving digoxin gave the following relationship: Vitros = 0.91 x AxSYM + 0.23 (r = 0.97, Sy,x = 0.12). Digoxinlike immunoreactive factor (DLIF) crossreactivity was examined in specimens from patients who had hepatic disease, renal insufficiency, had undergone cardiac surgery, and in neonatal cord blood samples. Minimal crossreactivity was observed for most samples and the average crossreactivity for each group of samples was comparable for the two methods. The recovery of digoxin added to samples from each group of DLIF was similar, except for that from cord blood samples, for which recovery was significantly lower with the AxSYM method. Titration of a digoxin-spiked serum pool with digoxin-immune Fab showed a similar decrease in the measured digoxin concentration for both methods. Overall, the analytic performance characteristics of these two methods were comparable. 相似文献
5.
Julie Isabelle Plougmann Pia Klausen John Gásdal Karstensen Peter Vilmann Jane Preuss Hasselby Carsten Palnæs Hansen 《Scandinavian journal of gastroenterology》2017,52(9):932-940
Pancreatic cysts are increasingly diagnosed due to the widespread use of cross-sectional imaging, and some of these lesions harbor malignant potential. Mucinous cystic neoplasms and intraductal papillary mucinous neoplasms are the major premalignant cystic neoplasms of the pancreas. A variety of diagnostic tools are used to predict the malignant potential of these cysts, but specificity and sensitivity are limited. Thus, many patients undergo unnecessary operations for benign cysts. Balancing the risks of watchful waiting with those of operative management is key in managing these lesions. During the last decade, genetic changes of pancreatic cysts have been examined extensively to estimate their malignant potential. In this review, we provide an overview of the latest molecular and genetic aspects of pancreatic cysts and how they may contribute to the differential diagnosis in patients with pancreatic cystic neoplasms. 相似文献
6.
Schmits R Kubuschok B Schuster S Preuss KD Pfreundschuh M 《Clinical and experimental immunology》2002,127(2):379-385
The analysis of the antibody repertoire of patients with giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) might identify target antigens of the autoimmune response with potential relevance to our understanding of the pathogenesis of the disease and to the development of serodiagnostic tests. To detect such antigens, we screened a cDNA library derived from normal human testis for antigens reacting with IgG antibodies in the 1 : 250 diluted sera of three patients with untreated GCA using SEREX, the serological identification of antigens by recombinant cDNA expression cloning. Of 100 000 clones screened with each serum, six, 28 and six clones, respectively, were positive, representing a total of 33 different antigens. Most of the antigens reacted only with the serum used for identification and/or at a similar frequency with normal control sera. However, lamin C and the nuclear antigen of 14 kD reacted specifically with 32% of GCA/PMR, but with none of the control sera, while human cytokeratin 15, mitochondrial cytochrome oxidase subunit II, and a new gene product were detected preferentially, but not exclusively by sera from GCA/PMR patients. We conclude that patients with GCA/PMR develop antibodies against a broad spectrum of human autoantigens. Antibodies against human lamin C, the nuclear autoantigen of 14 kD as well as human cytokeratin 15, mitochondrial cytochrome oxidase subunit II and the product of a new gene should be investigated further to determine their value as tools for the diagnosis and/or the definition of clinical subgroups of patients with GCA/PMR. 相似文献
7.
Zinn Klose Dinkler W. Fischer Pendl Rust Sperling Mader Koch Hüsselrath Rosenhagen Preuss 《Journal of molecular medicine (Berlin, Germany)》1939,18(11):393-397
Ohne Zusammenfassung 相似文献
8.
Vaternahm Rosenhagen Dinkler Fuchs Hüsselrath Pendl Uhlmann W. Fischer Bernhardt Koch F. Fischer Lehrnbecher Sperling Preuss 《Journal of molecular medicine (Berlin, Germany)》1938,17(23):824-827
Ohne Zusammenfassung 相似文献
9.
10.