全文获取类型
收费全文 | 609篇 |
免费 | 71篇 |
国内免费 | 1篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 7篇 |
2020年 | 11篇 |
2019年 | 9篇 |
2018年 | 15篇 |
2017年 | 16篇 |
2016年 | 15篇 |
2015年 | 22篇 |
2014年 | 22篇 |
2013年 | 32篇 |
2012年 | 41篇 |
2011年 | 38篇 |
2010年 | 28篇 |
2009年 | 16篇 |
2008年 | 27篇 |
2007年 | 24篇 |
2006年 | 24篇 |
2005年 | 25篇 |
2004年 | 35篇 |
2003年 | 17篇 |
2002年 | 32篇 |
2001年 | 20篇 |
2000年 | 17篇 |
1999年 | 18篇 |
1998年 | 12篇 |
1997年 | 12篇 |
1996年 | 10篇 |
1995年 | 12篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 13篇 |
1991年 | 9篇 |
1990年 | 11篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 6篇 |
1981年 | 2篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1976年 | 2篇 |
1975年 | 6篇 |
1968年 | 2篇 |
1960年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有681条查询结果,搜索用时 15 毫秒
61.
Paloma Moreno Moreno Carmen Gutiérrez Alcántara María del Carmen Muñoz-Villanueva Rafael Palomares Ortega María del Sierra Corpas Jiménez Luis Zurera Tendero Pedro Benito López 《Endocrinología y nutrición》2010,57(3):95-99
Background and objectiveThe aim of this study was to assess the utility of arterial calcium stimulation with hepatic venous sampling (ASVS) in the localization of tumors in patients with endogenous hyperinsulinism not detected with other methods.Patients and methodsWe performed a retrospective study of 26 patients admitted to our hospital for hypoglycemia who underwent ASVS because the source of hyperinsulinism was not clearly identified by other imaging techniques. The histopathological result in patients who underwent a surgical procedure was considered the reference for statistical study of the accuracy of this technique. Statistical analysis was performed by comparing proportions with the chi-squared test with Yates’ correction for contingency tables, and Cohen′s kappa coefficient as a measure of interrater agreement between two observations.ResultsSurgery was performed in 17 patients, 13 with positive ASVS and the remaining four with negative results. An insulinoma was removed in 12 patients, and 10 of these were detected in the ASVS. A total of 76.9 % of positive ASVS tests corresponded to a histological diagnosis of insulinoma, and 83% of these insulinomas were positive in ASVS. This association was statistically significant (chi cuadrado = 7.340; p = 0.012). Two of three patients with nesidioblastosis had a positive response in the ASVS. A good and statistically significant agreement was obtained between histopathologic diagnosis and ASVS results (κ=0.556, p = 0.007).ConclusionsASVS is a useful procedure in the localization diagnosis of endogenous hyperinsulinism not detected by other imaging tests. This technique allows tumors in the pancreatic gland to be identified and may be useful in the choice of the surgical technique to be used. 相似文献
62.
O. Dauwalder A. -M. Freydière H. Meugnier Y. Benito M. Chomarat C. Ginevra P. Girardo M. -E. Reverdy J. Etienne G. Lina F. Vandenesch 《Bio Tribune Magazine》2010,36(1):6-11
Concomitant chemoradiotherapy can constitute an alternative to surgical approach in selected patients with bladder carcinoma. TNM staging, histological grading, renal and performance status represent the main prognostic factors useful to define the therapeutic strategy. Biological and genetic factors are still controversial in medical practice. The activation of oncogenes seems to characterize the initiation of superficial lowgrade tumors and the mutations in the tumor suppressor genes (TEN, TP53 and RB) appear as the most important biological features in the in situ and invasive tumors. The expression of p53, Rb, Bcl-2 has an obvious prognostic role but the published studies on molecular factors predictive of radiosensibility are heterogeneous. 相似文献
63.
Victoria Álvarez Elena Sánchez-Ferrero Christian Beetz Marta Díaz Belén Alonso Ana I Corao Josep Gámez Jesús Esteban Juan F Gonzalo Samuel I Pascual-Pascual Adolfo López de Munain Germán Moris Renne Ribacoba Celedonio Márquez Jordi Rosell Rosario Marín Maria J García-Barcina Emilia del Castillo Carmen Benito Eliecer Coto 《BMC neurology》2010,10(1):1-9
Background
Although some epidemiologic studies found inverse associations between alcohol drinking and Parkinson's disease (PD), the majority of studies found no such significant associations. Additionally, there is only limited research into the possible interactions of alcohol intake with aldehyde dehydrogenase (ALDH) 2 activity with respect to PD risk. We examined the relationship between alcohol intake and PD among Japanese subjects using data from a case-control study.Methods
From 214 cases within 6 years of PD onset and 327 controls without neurodegenerative disease, we collected information on "peak", as opposed to average, alcohol drinking frequency and peak drinking amounts during a subject's lifetime. Alcohol flushing status was evaluated via questions, as a means of detecting inactive ALHD2. The multivariate model included adjustments for sex, age, region of residence, smoking, years of education, body mass index, alcohol flushing status, presence of selected medication histories, and several dietary factors.Results
Alcohol intake during peak drinking periods, regardless of frequency or amount, was not associated with PD. However, when we assessed daily ethanol intake separately for each type of alcohol, only Japanese sake (rice wine) was significantly associated with PD (adjusted odds ratio of ≥66.0 g ethanol per day: 3.39, 95% confidence interval: 1.10-11.0, P for trend = 0.001). There was no significant interaction of alcohol intake with flushing status in relation to PD risk.Conclusions
We did not find significant associations between alcohol intake and PD, except for the daily amount of Japanese sake. Effect modifications by alcohol flushing status were not observed. 相似文献64.
S. Benito F. Palomero A. Morata F. Calderón J.A. Suárez-Lepe 《Journal of applied microbiology》2009,106(5):1743-1751
Aims: The formation of ethylphenols in wines, a consequence of Dekkera/Brettanomyces metabolism, can affect their quality. The main aims of this work were to further our knowledge of Dekkera/Brettanomyces with respect to ethylphenol production, and to develop a methodology for detecting this spoilage yeast and for estimating its population size in wines using differential-selective media and high performance liquid chromatography (HPLC).
Methods and Results: This work examines the reduction of p -coumaric acid and the formation of 4-vinylphenol and 4-ethylphenol (recorded by HPLC-DAD) in a prepared medium because of the activities of different yeast species and populations. A regression model was constructed for estimating the population of Dekkera/Brettanomyces at the beginning of fermentation via the conversion of hydroxycinnamic acids into ethylphenols.
Conclusions: The proposed methodology allows the populations of Dekkera/Brettanomyces at the beginning of fermentation to be estimated in problem wines. Moreover, it avoids false positives because of yeasts resistant to the effects of the selective elements of the medium.
Significance and Impact of the Study: This may help prevent the appearance of organoleptic anomalies in wines at the winery level. 相似文献
Methods and Results: This work examines the reduction of p -coumaric acid and the formation of 4-vinylphenol and 4-ethylphenol (recorded by HPLC-DAD) in a prepared medium because of the activities of different yeast species and populations. A regression model was constructed for estimating the population of Dekkera/Brettanomyces at the beginning of fermentation via the conversion of hydroxycinnamic acids into ethylphenols.
Conclusions: The proposed methodology allows the populations of Dekkera/Brettanomyces at the beginning of fermentation to be estimated in problem wines. Moreover, it avoids false positives because of yeasts resistant to the effects of the selective elements of the medium.
Significance and Impact of the Study: This may help prevent the appearance of organoleptic anomalies in wines at the winery level. 相似文献
65.
66.
A cDNA that encodes a transporter from the NHAD family was identified in Physcomitrella patens. Computer-based searches using the amino acid sequence of PpNHAD1 revealed that, in addition to being expressed in flowering plants, highly conserved transporters of this family are expressed in red algae, green algae, mosses, liverworts, and photosynthetic stramenopiles, but not in heterotrophic stramenopiles. A chloroplast transit peptide was detected in PpNHAD1 and in most of the related sequences, indicating that PpNHAD1 is a chloroplast transporter. A PpNHAD1-GFP fusion localized to the chloroplast in Physcomitrella protoplasts, and truncation of the N-terminus of the protein dispersed the fluorescence signal outside the chloroplast. PpNHAD1 did not show functional expression in either yeast or bacterial mutants, but truncated proteins with shorter N-termini, PpNHAD1-1 and PpNHAD1-2, could be functionally expressed in bacteria. PpNHAD1-1 alleviated the Li(+) intolerance of a Na(+)-efflux Escherichia coli mutant at acidic pH values. Both PpNHAD1-1 and PpNHAD1-2 reduced the K(+) requirements of a K(+)-influx E. coli mutant more actively at high pH values. PpNHAD1 seems to be an important transporter that mediates ionic homeostasis in chloroplasts from red algae to flowering plants. 相似文献
67.
The tomato res mutant which accumulates JA in roots in non‐stressed conditions restores cell structure alterations under salinity
下载免费PDF全文
![点击此处可从《Physiologia plantarum》网站下载免费的PDF全文](/ch/ext_images/free.gif)
68.
69.
70.
Fischer C Shah S Hughes BL Nikov GN Crispino JL Middleton RE Szewczak AA Munoz B Shearman MS 《Bioorganic & medicinal chemistry letters》2011,21(2):773-776
Synthesis, SAR and evaluation of styrenyl quinazolinones as novel gamma secretase modulators are presented in this communication. Starting from literature and in-house leads we evaluated a range of quinazolinones which showed good modulation of γ-secretase activity. 相似文献