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641.
Samaras V Piperi C Korkolopoulou P Zisakis A Levidou G Themistocleous MS Boviatsis EI Sakas DE Lea RW Kalofoutis A Patsouris E 《Molecular and cellular biochemistry》2007,304(1-2):343-351
Glioblastoma, (grade IV astrocytoma), is characterized by rapid growth and resistance to treatment. Identification of markers
of aggressiveness in this tumor could represent new therapeutic targets. Interleukins (IL)-6 and IL-10 may be considered as
possible candidates, regulating cell growth, resistance to chemotherapy and angiogenesis. ELISPOT method provides a useful
tool for the determination of the exact cell number of peripheral lymphocytes secreting a specific cytokine. IL-6 and IL-10
secretion levels were determined using ELISPOT methodology in peripheral blood mononuclear cells of 18 patients with astrocytic
neoplasms (3 grade II and 15 grade IV), in parallel with 18 healthy controls. Additionally, immunohistochemical expression
of these two cytokines was performed in paraffin-embedded neoplastic tissue in 12 of these patients. The secretion of IL-6
from peripheral monocytes was significantly higher in glioma patients compared to controls (P = 0.0003). In addition, IL-10 secretion from peripheral mononuclear and tumor cells of glioma patients was also higher as
compared to healthy controls (P = 0.0002). Based on immunohistochemical staining, IL-6 expression was localized in tumor cells and macrophages as well as
in areas of large ischemic necrosis, while the major source of IL-10 expression in glioblastomas was the microglia/macrophage
cells. It is suggested that IL-10 contributes to the progression of astrocytomas by suppressing the patient’s immune response,
whereas IL-6 provides an additional growth advantage. This study demonstrates for the first time the usefulness of ELISPOT
in estimating the secretion of IL-6 and IL-10 from peripheral blood and the correlation of their expression in neoplastic
cells.
Christina Piperi and Penelope Korkolopoulou have equally contributed to this work. 相似文献
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643.
George Tsikouris Ioannis Antonopoulos Dionysia Vasdeki Dimosthenis Chrysikos Athanasios Koukakis George Tsakotos Panagiotis Georgakopoulos Theodore Troupis 《Journal of brachial plexus and peripheral nerve injury》2021,16(1):e31
Background The suprascapular notch (SN) represents the point along the route of the suprascapular nerve (SSN) with the greatest potential risk for injury and compression. Thus, factors reducing the area of the notch have been postulated for suprascapular neuropathy development. Methods Thirty-one fresh-frozen shoulders were dissected. The contents of the SN were described according to four types as classified by Polguj et al and the middle-transverse diameter of the notch was measured. Also, the presence of an ossified superior transverse scapular ligament (STSL) was identified. Results The ligament was partially ossified in 8 specimens (25.8%), fully ossified in 6 (19.35%), and not ossified in the remaining 17 (54.85%). The mean middle-transverse diameter of the SN was 9.06 mm (standard deviation [SD] = 3.45). The corresponding for type-I notches was 8.64 mm (SD = 3.34), 8.86 mm (SD = 3.12) was for type-II, and 14.5 mm (SD = 1.02) was for type III. Middle-transverse diameter was shorter when an ossified ligament was present (mean = 5.10 mm, SD = 0.88 mm), comparing with a partially ossified ligament (mean =7.67 mm, SD = 2.24 mm) and a nonossified one (mean = 11.12 mm, SD = 2.92 mm). No statistically significant evidence was found that the middle-transverse diameter depends on the number of the elements, passing below the STSL. Conclusion Our results suggest that SSN compression could be more likely to occur when both suprascapular vessels pass through the notch. Compression of the nerve may also occur when an ossified transverse scapular ligament is present, resulting to significant reduction of the notch''s area. 相似文献
644.
Christina Karpouzi Stefanos Nikolaidis Athanasios Kabasakalis George Tsalis Vassilis Mougios 《Biomarkers》2016,21(3):204-207
Physical exercise can induce oxidative damage in humans. 8-Hydroxy-2′-deoxyguanosine (8-OHdG) is a widely known biomarker of DNA oxidation, which can be determined in blood and urine. The aim of the present study was to compare these two biological fluids in terms of which is more suitable for the estimation of the oxidative damage of DNA by measuring the concentration of 8-OHdG one hour after maximal exercise by enzyme immunoassay. The concentration of 8-OHdG increased with exercise only in plasma (p?<?0.001), and values differed between exercise tests in both plasma and urine (p?<?0.05). In conclusion, plasma appears to be more sensitive to exercise-induced 8-OHdG changes than urine and, hence, a more appropriate medium for assessing oxidative damage of DNA, although the poor repeatability of the measurement needs to be addressed in future studies 相似文献
645.
Reliability of urine lactate as a novel biomarker of lactate production capacity in maximal swimming
Stefanos Nikolaidis Christina Karpouzi George Tsalis Athanasios Kabasakalis Konstantinos G. Papaioannou Vassilis Mougios 《Biomarkers》2016,21(4):328-334
Context: Postexercise urine lactate may be a novel biomarker of lactate production capacity during exercise.Objective: To evaluate the reliability and utility of the urine lactate concentration after maximal swimming trials between different training protocols (6?×?50?m and 3?×?100?m) and training states (active and nonactive swimmers).Materials and methods: Lactate and creatinine were determined by spectrophotometry in blood and urine.Results: Blood and urine lactate concentrations were correlated in-between training protocols and in participants of different training states. The reliability of the urine lactate concentration was moderate for one of the training protocols and good or moderate for the two training states. Additionally, it was lower than that of the blood lactate concentration, and did not improve after normalizing to the urine creatinine concentration.Discussion and conclusion: Although promising as a biomarker of lactate production capacity, urine lactate requires further research to improve its reliability. 相似文献
646.
Mannino C Nievo M Machetti F Papakyriakou A Calderone V Fragai M Guarna A 《Bioorganic & medicinal chemistry》2006,14(22):7392-7403
Starting from 3-aza-6,8-dioxa-bicyclo[3.2.1]octane scaffold (BTAa) a virtual library of molecules was generated and screened in silico against the crystal structure of the Human Macrophage Metalloelastase (MMP-12). The molecules obtaining high score were synthesized and the affinity for the catalytic domain of MMP-12 was experimentally proved by NMR experiments. A BTAa scaffold 20 having a N-hydroxyurea group in position 3 and a p-phenylbenzylcarboxy amide in position 7 showed a fair inhibition potency (IC50 = 149 microM) for MMP-12 and some selectivity towards five different MMPs. These results, taken together with the X-ray structure of the adduct between MMP-12, the inhibitor 20 and the acetohydroxamic acid (AHA), suggest that bicyclic scaffold derivatives may be exploited for the design of new selective matrix metalloproteinase inhibitors (MMPIs). 相似文献
647.
648.
Somatic angiotensin-converting enzyme (ACE) contains two homologous domains, each bearing a functional active site. Studies on the selectivity of these ACE domains towards either substrates or inhibitors have mostly relied on the use of mutants or isolated domains of ACE. To determine directly the selectivity properties of each ACE domain, working with wild-type enzyme, we developed an approach based on the combined use of N-domain-selective and C-domain-selective ACE inhibitors and fluorogenic substrates. With this approach, marked differences in substrate selectivity were revealed between rat, mouse and human somatic ACE. In particular, the fluorogenic substrate Mca-Ala-Ser-Asp-Lys-DpaOH was shown to be a strict N-domain-selective substrate of mouse ACE, whereas with rat ACE it displayed marked C-domain selectivity. Similar differences in selectivity between these ACE species were also observed with a new fluorogenic substrate of ACE, Mca-Arg-Pro-Pro-Gly-Phe-Ser-Pro-DpaOH. In support of these results, changes in amino-acid composition in the binding site of these three ACE species were pinpointed. Together these data demonstrate that the substrate selectivity of the N-domain and C-domain depends on the ACE species. These results raise concerns about the interpretation of functional studies performed in animals using N-domain and C-domain substrate selectivity data derived only from human ACE. 相似文献
649.
Sidira M Galanis A Ypsilantis P Karapetsas A Progaki Z Simopoulos C Kourkoutas Y 《Journal of molecular microbiology and biotechnology》2010,19(4):224-230
The aim of the present study was to assess the survival of free and immobilized Lactobacillus casei ATCC 393 on apple pieces, contained in probiotic-fermented milk, after gastrointestinal (GI) transit and to investigate the potential regulation of intestinal microbial flora in a rat model. In in vitro GI stress tolerance tests, immobilized L. casei ATCC 393 exhibited significantly higher survival rates compared to free cells. At a second stage, probiotic-fermented milk produced by either free or immobilized cells was administered orally at a single dose or daily for 9 days in Wistar rats. By 12 h after single-dose administration, both free and immobilized cells were detected by microbiological and molecular analysis at levels ≥6 logCFU/g of feces. Moreover, daily administration led to significant reduction of staphylococci, enterobacteria, coliforms and streptococci counts. In conclusion, L. casei ATCC 393 contained in fermented milk survived GI transit and modulated intestinal microbiota. 相似文献
650.
Petros Skapinakis Eleni Bakola Georgia Salanti Glyn Lewis Athanasios P Kyritsis Venetsanos Mavreas 《BMC neurology》2010,10(1):49