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351.
Okadaic acid accumulation in macrofilter feeders subjected to natural blooms of Dinophysis acuminata
Sofia Reizopoulou Evangelia Strogyloudi Antonia Giannakourou Kalliopi Pagou Ioannis Hatzianestis Christina Pyrgaki Edna Granli 《Harmful algae》2008,7(2):228-234
Thermaikos Gulf is a eutrophic area located in the Northwestern part of the Aegean Sea in the Eastern Mediterranean. Interspecific differences among various filter feeders in their ability to accumulate okadaic acid, were observed during natural blooms of Dinophysis acuminata in the gulf. Okadaic acid analyses by high performance liquid chromatography (HPLC) were performed on benthic specimens and D. acuminata cell densities and cell toxin content were estimated in water samples. Seven filter feeding species were collected in the gulf during two DSP outbreaks in May 2003 and March 2004. The various species showed a different potential to accumulate okadaic acid in their tissues. The highest concentrations were found in the mussel populations (Mytilus galloprovincialis and Modiolus barbatus), while among the non-bivalve filter feeders, ascidians were the main accumulators of okadaic acid. The rest of shellfish populations (Flexopecten proteus, Chlamys varia and Venus verrucosa) were found to contain toxins only during 2004, when D. acuminata densities were found above 10000 cells l−1. M. galloprovincialis was proved to be the most appropriate indicator for a safe warning of okadaic acid contamination in Thermaikos Gulf. 相似文献
352.
Papantoniou V Valsamaki P Sotiropoulou E Tsaroucha A Tsiouris S Sotiropoulou M Marinopoulos S Kounadi E Karianos T Fothiadaki A Archontaki A Syrgiannis K Ptohis N Makris N Limouris G Antsaklis A 《Molecular imaging》2011,10(5):370-376
The purpose of this study was to assess the relationship of mammographic breast density (BD) and cell proliferation/focal adhesion kinase activation-seeking radiotracer technetium 99m pentavalent dimercaptosuccinic acid (99mTc(V)-DMSA) uptake in women with different breast histologies, that is, mild epithelial hyperplasia (MEH), florid epithelial hyperplasia (FEH), mixed ductal carcinoma in situ with invasive ductal carcinoma (DCIS + IDC), and pure IDC. Fifty-five women with histologically confirmed mammary pathologies were submitted preoperatively to mammography and 99mTc(V)-DMSA scintimammography. The percentage and intensity of 99mTc(V)-DMSA uptake and the percentage of BD were calculated by computer-assisted methods and compared (t-test) between the breast pathologies.?In breasts with increased BD, FEH and DCIS + IDC were found. On the contrary, pure IDC and MEH were identified in breasts with significantly lower BD values. In breasts with increased 99mTc(V)-DMSA area and intensity of uptake, FEH was the main lesion found compared to all other histologies. Linear regression analysis between BD and 99mTc(V)-DMSA uptake area and intensity revealed significant coefficients of correlation (r = .689, p < .001 and r = .582, p < .001, respectively). Increased BD correlates with the presence of FEH and mixed DCIS + IDC but not with pure IDC or MEH. Its close relationship to 99mTc(V)-DMSA, which also showed an affinity to FEH, indicates that stromal microenvironment may constitute a specific substrate leading to progression to different subtypes of cancerous lesions originating from different pathways. 相似文献
353.
354.
Evangelia Vretou Petros Eliades Evgenia Psarrou Raina Kouvatsou 《FEMS microbiology letters》1992,91(3):225-230
HeLa-cell-membrane fractions isolated by sonication as used previously to identify chlamydial adhesins were examined by a blotting technique for binding chlamydial elementary bodies (EB). One HeLa cell protein with apparent molecular mass of 32 kDa was found to bind native EB. A monoclonal antibody (mAb) raised against this chlamydial binding host-cell protein reacted with eucaryotic histones. Histone fractions were capable of binding EB in an ELISA assay and histone H1 was identified as the chlamydial-binding host cell protein in the Hela cell membrane fraction. Probing with specific mAbs against histone H3 and DNA confirmed that chromatin components were present in the host-cell membrane extract. These data suggest that the HeLa-cell-binding chlamydial proteins were previously identified by their reaction with chromatin and not with membrane components. 相似文献
355.
Vassilis Tsafas Evangelia Gavgiotaki Maria Tzardi Effrosyni Tsafa Costas Fotakis Irene Athanassakis George Filippidis 《Journal of biophotonics》2020,13(10)
Nonlinear optical imaging techniques have been widely used to reveal biological structures for accurate diagnosis at the cellular as well as the tissue level. In the present study, polarization‐dependent second‐harmonic generation (PSHG) was used to determine collagen orientation in breast cancer biopsy tissues (grades 0, I, II and III). The obtained data were processed using fast Fourier transform (FFT) analysis, while second‐harmonic generation (SHG) anisotropy and the “ratio parameter” values were also calculated. Such measurements were shown to be able to distinguish collagen structure modifications in different cancer grades tested. The analysis presented herein suggests that PSHG imaging could provide a quantitative evaluation of the tumor state and the distinction of malignant from benign breast tissues. The obtained results also allowed the development of a biophysical model, which can explain the aforementioned differentiations and is in agreement with the simulations relating the SHG anisotropy values with the mechanical tension applied to the collagen during cancer progression. The current approach could be a step forward for the development of new, nondestructive, label free optical diagnostic tools for cancer reducing the need of recalls and unnecessary biopsies, while potentially improving cancer detection rates. 相似文献
356.
Costas Perdikaris Anna Ergolavou Evangelia Gouva Cosmas Nathanailides Athanasios Chantzaropoulos Ioannis Paschos 《Reviews in Fish Biology and Fisheries》2012,22(1):17-27
Ichthyofauna in the Hellenic freshwaters is quite diverse consisted of 161 species (including 28 non-natives), out of the
546 native species in Pan-European level. However, the status of many aquatic ecosystems is currently degraded as a result
of a variety of anthropogenic impacts. This has direct reflection on the conservation status of the indigenous and native
fish species whose populations are in many cases declining in favor of the invasive ones. Prussian carp (Carassius
gibelio) is probably the most dominant invasive species and currently is considered as naturalized in about 26 lake and river basins.
Its successful adaptation and proliferation is mainly attributed to its dual reproductive mode (allogynogenetic and gonochoristic),
the opportunistic-omnivorous feeding habits and the ability to withstand and flourish in adverse ecological conditions. Accordingly,
it exerts competitive, as well as destructive effects upon the indigenous fish species (sperm parasitism, antagonism for food,
spawning grounds and spawning substrates) and therefore, efforts are needed to sustain a relative balance of the populations.
This review aims to critically discuss the status of C.
gibelio in Greece, the intrinsic causes of establishment and the observed impacts on ecosystems. Finally, reasonable actions are
proposed related to exploitation of C.
gibelio stocks and a path model for the protection of native fish species and their ecosystems. 相似文献
357.
358.
Yannis Manios Georgia Kourlaba Katerina Kondaki Evangelia Grammatikaki Anastasia Anastasiadou Eleytheria Roma‐Giannikou 《Obesity (Silver Spring, Md.)》2009,17(11):2047-2053
The aim of the current work was to evaluate the effect of preschoolers' television (TV) watching time on the prevalence of obesity even after controlling for their total energy intake and their physical activity status. A representative sample of 2,374 Greek children aged 1–5 years was examined (“Growth, Exercise and Nutrition Epidemiological Study in preSchoolers”, GENESIS study). Children's TV watching time on a usual weekday and at a usual weekend was recorded. The overall mean of children's TV viewing time was 1.32 h/day. The majority of participants (74.0%) spent <2 h/day watching TV whereas only 3.1% spent >4 h/day in front of a TV set. Overall, 65.2% of participants were normal weight, 17.2% were overweight, and the rest 17.6% were obese. The prevalence of obesity was significantly higher among those with TV viewing time ≥2 h/day (21.7%) compared to those watching TV <2 h/day (16.1%, P = 0.003). TV viewing time remained significantly associated with the likelihood of being obese even after controlling for potential confounders (i.e., socio demographic and other characteristics and physical activity status) only among children aged 3–5 years. However, further adjusting for children's total energy intake revealed that the association between the TV viewing time and the probability of being obese was no longer statistically significant. On the other hand, physical activity status continued to be an independent factor of being obese. The current findings support the hypothesis that the effect of TV viewing time on childhood obesity is independent of physical activity status and may be attributed to the increased total energy intake during TV watching. 相似文献
359.
Persefoni Klimentzou Angeliki Drougou Birgit Fehrenbacher Martin Schaller Wolfgang Voelter Calypso Barbatis Maria Paravatou-Petsotas Evangelia Livaniou 《The journal of histochemistry and cytochemistry》2008,56(11):1023-1031
Prothymosin α (ProTα) is a nuclear polypeptide of great biological and, possibly clinical, importance, because its expression levels have been associated with early diagnosis/prognosis of human cancer. It is therefore interesting to raise easily available and cost-effective antibodies that would be applied to develop reliable ProTα immunodiagnostics. In this study, New Zealand white rabbits and laying hens were parallel immunized against intact ProTα or the synthetic fragments ProTα[1-28], ProTα[87-109], and ProTα[101-109], all conjugated to keyhole limpet hemocyanin (KLH). The corresponding antibodies G and Y were immunochemically evaluated in parallel with ELISA and Western blot systems and applied to fluorescence immunocytology experiments using various cancer cell lines and normal cells. The antibody G raised against ProTα[101-109]/KLH had excellent functional characteristics in the Western blot and immunocytology experiments, where the fluorescent signal was almost exclusively shown in the cell nucleus independently of the cells assayed. The above antibody has been applied to preliminary IHC staining of human cancer prostate tissues, leading to a high percentage of clearly and intensively stained nuclei in the adenocarcinoma tissue; this antibody can be further used in cancer tissue immunostaining and in research concerning the role of ProTα in tumorigenesis. (J Histochem Cytochem 56:1023–1031, 2008) 相似文献