全文获取类型
收费全文 | 438篇 |
免费 | 43篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 10篇 |
2019年 | 19篇 |
2018年 | 20篇 |
2017年 | 21篇 |
2016年 | 31篇 |
2015年 | 42篇 |
2014年 | 24篇 |
2013年 | 28篇 |
2012年 | 23篇 |
2011年 | 29篇 |
2010年 | 24篇 |
2009年 | 14篇 |
2008年 | 22篇 |
2007年 | 19篇 |
2006年 | 14篇 |
2005年 | 17篇 |
2004年 | 14篇 |
2003年 | 13篇 |
2002年 | 13篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1974年 | 3篇 |
1972年 | 1篇 |
1971年 | 2篇 |
排序方式: 共有481条查询结果,搜索用时 93 毫秒
1.
2.
E Giannazzo F Licata G Li Volsi G Mio F Santangelo M Scivoli 《Bollettino della Società italiana di biologia sperimentale》1992,68(11):677-683
A computer-assisted analysis of the spatial distribution of neurons having homogeneous characteristics is described in this paper. The camera lucida drawings of sections of a brain nucleus and the points representing the neurons labeled on the basis of a specific behavior of discharge rates were digitized on a personal computer Amiga 2000 or IBM compatible. Our software provided: a) the computerized, stereotaxically oriented reconstruction of the stored sections and of the plotted neurons; b) the identification within each section of the mass center (MC) of the units sharing a given behavior and of the area where the density of such neurons was maximal (MDA). The routine was tested on the spatial distribution of neuronal responses to serotonin in the lateral vestibular nucleus. 相似文献
3.
G Licata G B Rini A M Di Chiara G Di Fede M R Averna G Montalto A Notarbartolo 《Bollettino della Società italiana di biologia sperimentale》1983,59(4):489-492
In 45 type 2 diabetics it was unable to be found a relation between the plasma lipids and the fasting blood glucose (G), HbA1c, reverse T3 (rT3), rT3/T3 ratio, and relative body weight (R.B.W.). The conclusion was reached that the alteration of the lipoprotein metabolism and the thyroid hormones in type 2 diabetics could be primitive and independent from the availability of the insulin. 相似文献
4.
G. Zaccone J. M. Lauweryns S. Fasulo G. Tagliafierro L. Ainis A. Licata 《Acta zoologica》1992,73(3):177-183
Neuroendocrine (NE) cells in the gills of six fish species were identified by serotonin and peptide immunohistochemistry. They occur either as single cells or as cell clusters within the filamental epithelium. Two populations of NE cells were identified that exhibit an immunoreactivity either for serotonin alone or for met-enkephalin and leu-enkephalin co-distributed in the same cells. We demonstrate for the first time the occurrence of open-type endocrine cells in the fish gill epithelium and confirm the presence of only serotonin-immunopositive cells of the closed type. The NE cells of the species studied do not react positively to other neuroendocrine markers occurring in the mammalian lung. Great differences probably exist in the expression of these epitopes on antigenic structures among various animal species. Although the physiological role of neuropeptides and serotonin in the fish gill NE cells is unknown, the presence of these molecular markers is of interest not only from an evolutionary aspect, but also in terms of a potential animal model to study the supposed functions of the airway neuroendocrine system in the vertebrates. 相似文献
5.
G Licata R Scaglione M A Dichiara G Parrinello G Capuana D Di Vincenzo 《Bollettino della Società italiana di biologia sperimentale》1984,60(10):1863-1869
The authors studied total and free circulating thyroid hormones, rT3, TBG and TSH behaviour on chronic liver disease in 11 subjects with cirrhosis of the liver with ascites(C.E.) and in 6 subjects with chronic active hepatitis (E.C.A.) in comparison with 15 healthy and euthyroid controls. Serum T3,FT3,T4 and FT4 levels were decreased significantly and serum rT3 values increased significantly both in the subjects with C.E. and in patients with E.C.A. Moreover no significantly changes of TSH and TBG levels has been found in 3 groups studied. These data suggest that the alteration of circulating thyroid hormones in chronic liver disease, may represent a compensatory way of reducing the patient's metabolic requirements. 相似文献
6.
Adenosine 5'-triphosphate synthesis induced by urea hydrolysis in Ureaplasma urealyticum. 总被引:9,自引:3,他引:6
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Although considerable attention has been devoted to the urea-hydrolyzing activity of Ureaplasma urealyticum, there is as yet no firmly established function for this enzyme. Present results support the idea that its activity generates a chemical gradient across the membrane which drives adenosine 5'-triphosphate synthesis through a chemiosmotic type of mechanism. 相似文献
7.
8.
Luana Lionetto Martina Ulivieri Matilde Capi Donatella De Bernardini Francesco Fazio Andrea Petrucca Leda Marina Pomes Ottavia De Luca Giovanna Gentile Barbara Casolla Martina Curto Gerardo Salerno Serena Schillizzi Maria Simona Torre Iolanda Santino Monica Rocco Paolo Marchetti Antonio Aceti Marina Borro 《生物化学与生物物理学报:疾病的分子基础》2021,1867(3):166042
Immune dysregulation is a hallmark of patients infected by SARS-CoV2 and the balance between immune reactivity and tolerance is a key determinant of all stages of infection, including the excessive inflammatory state causing the acute respiratory distress syndrome. The kynurenine pathway (KP) of tryptophan (Trp) metabolism is activated by pro-inflammatory cytokines and drives mechanisms of immune tolerance. We examined the state of activation of the KP by measuring the Kyn:Trp ratio in the serum of healthy subjects (n = 239), and SARS-CoV2-negative (n = 305) and -positive patients (n = 89). Patients were recruited at the Emergency Room of St. Andrea Hospital (Rome, Italy). Kyn and Trp serum levels were assessed by HPLC/MS-MS. Compared to healthy controls, both SARS-CoV2-negative and -positive patients showed an increase in the Kyn:Trp ratio. The increase was larger in SARS-CoV2-positive patients, with a significant difference between SARS-CoV2-positive and -negative patients. In addition, the increase was more prominent in males, and positively correlated with age and severity of SARS-CoV2 infection, categorized as follows: 1 = no need for intensive care unit (ICU); 2 ≤ 3 weeks spent in ICU; 3 ≥ 3 weeks spent in ICU; and 4 = death. The highest Kyn:Trp values were found in SARS-CoV2-positive patients with severe lymphopenia. These findings suggest that the Kyn:Trp ratio reflects the level of inflammation associated with SARS-CoV2 infection, and, therefore, might represent a valuable biomarker for therapeutic intervention. 相似文献
9.
Marcelo de Oliveira Barbosa Rubens Rodrigues da Silva Vanessa Carolina de Sena Correia Luana Pereira dos Santos Analía del Valle Garnero Ricardo José Gunski 《Genetics and molecular biology》2013,36(1):70-73
Cytogenetic studies in birds are still scarce compared to other vertebrates. Woodcreepers (Dendrocolaptidae) are part of a highly specialized group within the Suboscines of the New World. They are forest birds exclusive to the Neotropical region and similar to woodpeckers, at a comparable evolutionary stage. This paper describes for the first time the karyotypes of the Olivaceous and the Narrow-billed Woodcreeper using conventional staining with Giemsa and silver nitrate staining of the nucleolar organizer regions (Ag-NORs). Metaphases were obtained by fibular bone marrow culture. The chromosome number of the Olivaceous Woodcreeper was 2n = 82 and of the Narrow-billed Woodcreeper, 2n = 82. Ag-NORs in the largest macrochromosome pair and evidence of a chromosome inversion are described herein for the first time for this group. 相似文献
10.
Anna Licata Salvatore Corrao Salvatore Petta Chiara Genco Mauro Cardillo Vincenza Calvaruso Giuseppe Cabibbo Fatima Massenti Calogero Cammà Giuseppe Licata Antonio Craxì 《PloS one》2013,8(8)