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111.
Rafał Parada Magdalena Kawka Mariusz Sacharczuk Paweł Urbański Kazimierz Jaszczak 《Saudi Journal of Biological Sciences》2018,25(7):1406-1410
The aim of the current study was to characterize Polish Black-and-White cattle by morphological study of the Y chromosome. A total of 14 Y-linked microsatellites from UMN and INRA group were genotyped and assessed for polymorphism in a total 22 bulls. Cytogenetic studies in Polish Black-and-White bulls showed the existence of two morphological forms of Y chromosome. Among the 22 karyotypic analyzed bulls, 12 had submetacentric and 10 metacentric Y chromosome. The centromeric index of Y chromosome measured as percentage length of the p arm to total length ratio in the first case was 28 ± 3.97% and in the second 47 ± 7.28%, whereas the relative size of these chromosomes remained within the same range. Morphology and G- and C-banding patterns of both forms of Y chromosome were typical for other cattle breeds originating from Bos taurus. Out of a total of 14 microsatellite loci examined, 13 showed specific alleles for two forms of Y chromosome. In a pool of 62 alleles, 43 (69.3%) were common in the two groups of cattle, 19 (30.7%) can be considered as specific for the group; among them 8 were typical for metacentric group of Y chromosome and 11 for submetacentric. 相似文献
112.
The effect of seasonal changes and ecological aspects of Afrodiplozoon polycotyleus (Paperna, 1973) collected on Labeobarbus marequensis (Smith, 1841), Enteromius trimaculatus (Peters, 1852) and Enteromius radiatus (Peters, 1853) was investigated from January to October 2008. Fish were collected at the Nwanedi-Luphephe dams, Limpopo River System, South Africa using gill, cast and seine nets and electrofishing gear. Enteromius radiatus and E. trimaculatus were the most infested compared with L. marequensis. Seasonal changes had an influence on the intensity of A. polycotyleus, with infestation rates higher in spring, summer and autumn. The adults predominantly infected the medial region of the second gill arch, whereas diporpae were mainly found on the first gill. Neither sex nor water quality changes had an influence on the intensity of the parasite. The health condition of the hosts was not affected by the parasite. The different infestation rates of the parasite between the species could be attributed to host characteristics, behaviour and habitat preferences. The selection of a particular gill/region could be attributed to space for attachment organs and food supply, as well as flow and velocity of the water over the gills. The occurrence of A. polycotyleus on E. radiatus constitutes a new host record. 相似文献
113.
Background
Mixed culture enrichments have been used frequently for biohydrogen production from different feedstock. In spite of the several advantages offered by those cultures, they suffer poor H2 yield. Constructing defined co-cultures of known H2 producers may offer a better performance than mixed-population enrichments, while overcoming some of the limitations of pure cultures based on synergies among the microorganisms involved. 相似文献114.
Participation of plasma membrane proteins in the formation of tight junction by cultured epithelial cells 下载免费PDF全文
Measurements of the transepithelial electrical resistance correlated with freeze-fracture observations have been used to study the process of tight junction formation under various experimental conditions in monolayers of the canine kidney epithelial cell line MDCK. Cells derived from previously confluent cultures and plated immediately after trypsin- EDTA dissociation develop a resistance that reaches its maximum value of several hundred ohms-cm(2) after approximately 24 h and falls to a steady-state value of 80-150 ohms- cm(2) by 48 h. The rise in resistance and the development of tight junctions can be completely and reversibly prevented by the addition of 10 μg/ml cycloheximide at the time of plating, but not when this inhibitor is added more than 10 h after planting. Thus tight junction formation consists of separable synthetic and assembly phases. These two phases can also be dissociated and the requirement for protein synthesis after plating eliminated if, following trypsinization, the cells are maintained in spinner culture for 24 h before plating. The requirement for protein synthesis is restored, however, if cells maintained in spinner culture are treated with trypsin before plating. Actinomycin D prevents development of resistance only in monolayers formed from cells derived from sparse rather than confluent cultures, but new mRNA synthesis is not required if cells obtained from sparse cultures are maintained for 24 h in spinner culture before plating. Once a steady-state resistance has been reached, its maintenance does not require either mRNA or protein synthesis; in fact, inhibition of protein synthesis causes a rise in the resistance over a 30-h period. Following treatments that disrupt the junctions in steady- state monolayers recovery of resistance also does not require protein synthesis. These observations suggest that proteins are involved in tight junction formation. Such proteins, which do not turn over rapidly under steady-state conditions, are destroyed by trypsinization and can be resynthesized in the absence of stable cell-cell or cell-substratum contact. Messenger RNA coding for proteins involved in tight junction formation is stable except when cells are sparsely plated, and can also be synthesized without intercellular contacts or cell-substratum attachment. 相似文献
115.
Krzysztof Małecki Bogdan Gliński Anna Mucha-Małecka Janusz Ryś Anna Kruczak Krzysztof Roszkowski Marta Urbańska-Gąsiorowska Marcin Hetnał 《Reports of Practical Oncology and Radiotherapy》2010,15(4):87-92
Background
The optimal management of advanced laryngeal and hypopharyngeal cancers (L&HC) must involve consideration of both survival and functional effect of the given treatment approach. Despite over two decades of investigations of several treatment options, including surgery, radiotherapy, chemotherapy or some combinations thereof, little consensus exists as to which treatment offers the best survival, together with functional speech and swallowing.Aim
To determine predictive and prognostic value of p53, EGFr, Ki-67 in patients with advanced laryngeal and hypopharyngeal cancer, treated with larynx preservation intent.Materials and methods
Thirty-three patients received 2–3 cycles of induction chemotherapy (ICHT) consisting of cisplatin and fluoruracil and underwent subsequent radical radiotherapy. Immunohistochemical analyzes of p53, EGFr and Ki-67 were performed.Results
Response to ICHT was obtained in 24 patients (75%). Better response to ICHT was correlated only with EGFr expression (p = 0.04, RR = 1.91). The 5-year loco-regional control (LRC) and disease-specific survival (DSS) rates were 48% and 57%, respectively. The 5-year larynx preservation rate was 68% in responders to ICHT compared to 21% in non-responders (p = 0.02). It was also higher in patients without EGFr expression (but not significantly, p = 0.43).Conclusion
Lack of EGFr expression is a favorable predictive factor for response to ICHT. Neither p53 nor Ki-67 have predictive and prognostic value in larynx preservation treatment. 相似文献116.
WJ Richardson DD van der Voort E Wilson JE Moore Jr. 《Molecular & cellular biomechanics : MCB》2013,10(3):245-265
Non-uniform stress and strain fields are prevalent in many tissues in vivo, and often exacerbated by disease or injury. These mechanical gradients potentially play a role in contributing to pathological conditions, presenting a need for experimental tools to allow investigation of cell behavior within non-uniformly stimulated environments. Herein, we employ two in vitro cell-stretching devices (one previously published; one newly presented) capable of subjecting cells to cyclic, non-uniform stretches upon the surface of either a circular elastomeric membrane or a cylindrical PDMS tube. After 24 hours of cyclic stretch, 10T1/2 cells on both devices showed marked changes in long-axis orientation, with tendencies to align parallel to the direction of minimal deformation. The degree of this response varied depending on location within the stretch gradients. These results demonstrated the feasibility of conducting cell mechanobiology investigations with the two novel devices, while also highlighting the experimental capabilities of non-uniform mechanical environments for these types of studies. Such capabilities include robust data collection for developing mechanobiological dose-response curves, signal threshold identification, and potential spatial targeting for drug delivery. 相似文献
117.
CD28, TNF receptor,and IL-12 are critical for CD4-independent cross-priming of therapeutic antitumor CD8+ T cells 总被引:3,自引:0,他引:3
Hu HM Winter H Ma J Croft M Urba WJ Fox BA 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(9):4897-4904
Previously, we have shown that priming of therapeutic CD8(+) T cells in tumor vaccine-draining lymph nodes of mice vaccinated with GM-CSF secreting B16BL6 melanoma cells occurs independent of CD4 T cell help. In this study, we examined the contribution of the major costimulatory molecules, CD40 ligand (CD40L), CD80, and CD86, in the priming of CD8(+) T cells. Priming of therapeutic CD8(+) T cells by a GM-CSF-transduced tumor vaccine did not require CD40 and CD40L interactions, as therapeutic T cells could be generated from mice injected with anti-CD40L Ab and from CD40L knockout mice. However, costimulation via either CD80 or CD86 was required, as therapeutic T cells could be generated from mice injected with either anti-CD80 or anti-CD86 Ab alone, but administration of both Abs completely inhibited the priming of therapeutic T cells. Blocking experiments also identified that priming of therapeutic T cells in MHC class II-deficient mice required TNFR and IL-12 signaling, but signaling through CD40, lymphotoxin-betaR, or receptor activator of NF-kappaB was not essential. Thus, cross-priming of therapeutic CD8(+) T cells by a tumor vaccine transduced with GM-CSF requires TNFR, IL-12, and CD28 signaling. 相似文献
118.
119.
RW Meijers NH Litjens EA de Wit AW Langerak A van der Spek CC Baan W Weimar MG Betjes 《Immunity & ageing : I & A》2012,9(1):19-8
ABSTRACT: BACKGROUND: End-stage renal disease (ESRD) patients treated with renal replacement therapy (RRT) have premature immunologically aged T cells which may underlie uremia-associated immune dysfunction. The aim of this study was to investigate whether uremia was able to induce premature ageing of the T cell compartment. For this purpose, we examined the degree of premature immunological T cell ageing by examining the T cell differentiation status, thymic output via T cell receptor excision circle (TREC) content and proliferative history via relative telomere length in ESRD patients not on RRT. RESULTS: Compared to healthy controls, these patients already had a lower TREC content and an increased T cell differentiation accompanied by shorter telomeres. RRT was able to enhance CD8+ T cell differentiation and to reduce CD8+ T cell telomere length in young dialysis patients. An increased differentiation status of memory CD4+ T cells was also noted in young dialysis patients. CONCLUSION: Based on these results we can conclude that uremia already causes premature immunological ageing of the T cell system and RRT further increases immunological ageing of the CD8+ T cell compartment in particular in young ESRD patients. 相似文献
120.
Lotte Heimans Kirsten VC Wevers-de Boer KK Michel Koudijs Karen Visser Yvonne P Goekoop-Ruiterman Joop B Harbers Gerda M Steup-Beekman Leroy R Lard Bernard AM Grillet Tom WJ Huizinga Cornelia F Allaart 《Arthritis research & therapy》2013,15(5):R173