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An important issue in migration research is how small‐bodied passerines pass over vast geographical barriers; in European–African avian migration, these are represented by the Mediterranean Sea and the Sahara Desert. Eastern (passing eastern Mediterranean), central (passing Apennine Peninsula) and western (via western Mediterranean) major migration flyways are distinguished for European migratory birds. The autumn and spring migration routes may differ (loop migration) and there could be a certain level of individual flexibility in how individuals navigate themselves during a single migration cycle. We used light‐level loggers to map migration routes of barn swallows Hirundo rustica breeding in the centre of a wide putative contact zone between the northeastern and southernwestern European populations that differ in migration flyways utilised and wintering grounds. Our data documented high variation in migration patterns and wintering sites of tracked birds (n = 19 individuals) from a single breeding colony, with evidence for loop migration in all but one of the tracked swallows. In general, two migratory strategies were distinguished. In the first, birds wintering in a belt stretching from southcentral to southern Africa that used an eastern route for both the spring and autumn migration, then shifted their spring migration eastwards (anti‐clockwise loops, n = 12). In the second, birds used an eastern or central route to their wintering grounds in central Africa, shifting the spring migration route westward (clockwise loops, n = 7). In addition, we observed an extremely wide clockwise loop migration encompassing the entire Mediterranean, with one individual utilising both the eastern (autumn) and western (spring) migratory flyway during a single annual migration cycle. Further investigation is needed to ascertain whether clockwise migratory loops encircling the entire Mediterranean also occur other small long‐distance passerine species.  相似文献   
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BACKGROUND: Androgen receptor (AR) has emerged as a significant prognostic marker in early breast cancer (BCa). Association of AR with cancer stem cell (CSC) markers in BCa is unknown. Aim of the present study was to evaluate the immunohistochemical expression of AR, CD44, CD24 and ALDH1 in a cohort of Pakistani patients diagnosed with invasive BCa and to correlate the expression with 5- year disease free survival. PATIENTS AND METHODS: We evaluated immunohistochemical expression AR, CD44, CD24 and ALDH1 in formalin fixed paraffin embedded archival blocks of 166 cases of primary invasive BCa (stage I-III) and correlated the expression with clinicopathological variables and outcome using univariable and multivariable analysis. Survival data was computed by Kaplan Meier curves. RESULTS: Expression of AR was observed in 62.7% tumors whereas CD44, CD24 and ALDH1 were expressed in 61.4%, 44% and 30.1% tumors, respectively. AR expression was significantly associated with T1-T2 tumors, lower grade, estrogen and progesterone receptor expression (P < .05) and remained an independent prognostic indicator in multivariable analysis (adjusted HR 0.33, 95% CI 0.13–0.81; P = .016). Significant association was observed between concordant expression of AR and CD24 (P = .001) with a favorable impact on survival (P = .007) whereas expression of CSC phenotypes (CD44+, CD44+/CD24? and ALDH1+) did not correlate with adverse outcome (P > .05). However, AR expression retained the association with better prognosis even in patients whose tumors exhibited a CSC phenotype. CONCLUSIONS: Expression of AR and CD24 in stage I-III invasive BCa correlates with favorable clinicopathological features and delineates a subgroup of patients with better disease-free survival.  相似文献   
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The paper describes the bio efficacy of a protease inhibitor; isolated from Allium sativumgarlic’ (ASPI); against Aedes aegypti mosquito, a well-known transmitter of dengue and Chikungunya. The purification of protease inhibitor from Allium sativumgarlic’ (ASPI) was carried out by ammonium sulfate precipitation followed by Fast Protein Liquid Chromatography using akta DEAE-Cellulose column. The protein fraction demonstrating trypsin inhibitory activity was further evaluated for its insecticidal activity using gut protease inhibition assay and larvicidal assay. ASPI is an inhibitor of porcine trypsin (IC50 of 650.726?μg/mL) and has molecular weight of ~15?kDa determined by SDS PAGE similar to other inhibitors of the Kunitz-type family (14–26?kDa). ASPI demonstrated 50% reduced activity of Ae. aegypti midgut proteases and showed a dose-dependent acute toxicity on Ae. aegypti 3rd instars exhibiting LC50 value of ~50.827?μg/mL. After ten days of larval exposure ASPI resulted in a 24-h delay of larval development and ~72% mortality at 61.5?μg/mL. These results suggest that ASPI may serve as potent insecticidal agent and hence opens a new gateway in the field of phyto-remediation.  相似文献   
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According to the 'mitochondrial theory of aging' it is expected that the activity of NADH Coenzyme Q reductase (Complex I) would be most severely affected among mitochondrial enzymes, since mitochondrial DNA encodes for 7 subunits of this enzyme. Being these subunits the site of binding of the acceptor substrate (Coenzyme Q) and of most inhibitors of the enzyme, it is also expected that subtle kinetic changes of quinone affinity and enzyme inhibition could develop in aging before an overall loss of activity would be observed.The overall activity of Complex I was decreased in several tissues from aged rats, nevertheless it was found that direct assay of Complex I using artificial quinone acceptors may underevaluate the enzyme activity. The most acceptable results could be obtained by applying the 'pool equation' to calculate Complex I activity from aerobic NADH oxidation; using this method it was found that the decrease in Complex I activity in mitochondria from old animals was greater than the activity calculated by direct assay of NADH Coenzyme Q reductase.A decrease of NADH oxidation and its rotenone sensitivity was observed in nonsynaptic mitochondria, but not in synaptic 'light' and 'heavy' mitochondria of brain cortex from aged rats.In a study of Complex I activity in human platelet membranes we found that the enzyme activity was unchanged but the titre for half-inhibition by rotenone was significantly increased in aged individuals and proposed this change as a suitable biomarker of aging and age-related diseases. (Mol Cell Biochem 174: 329–333, 1997)  相似文献   
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Progenies of triploid and diploid hybrids of tetraploidArabis hirsuta (L.)Scop. s. str. and diploidA. sagittata (Bertol.) DC. andA. planisiliqua (Pers.) Reichenb. were studied. The observations concerned morphology, cytology, sterility degree of plants and embryological backgrounds. The evolutionary consequences of breakage of the sterility barriers within the complex connected with well pronouced morphological and karyological variability of hybrids are discussed.  相似文献   
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Lasioglossins are a group of peptides with identified antimicrobial activity. The inhibitory effects of two synthetic lasioglossin derivatives, LLIII and D‐isomeric variant LLIII‐D, on morphological changes in Candida albicans in vitro and the effect of local administration of LLIII during experimental murine candidiasis were investigated. C. albicans blastoconidia were grown in the presence of lasioglossin LLIII or LLIII‐D at concentrations of 11.5 μM and 21 μM, respectively, for 1, 2 and 3 days and their viability determined by flow cytometry using eosin Y staining. Morphological changes were examined by light and fluorescent microscopy. The Candida‐inhibitory effect of daily intravaginal administration of 0.7 or 1.4 μg of LLIII was assessed in mice with experimentally‐induced vaginal candidiasis. LLIII and LLIII‐D lasioglossins exhibited candidacidal activity in vitro (>76% after 24 hr and >84% after 48 hr of incubation). After 72 hr incubation of Candida with low concentration of lasioglossins, an increase in viability was detected, probably due to a Candida antimicrobial peptides evasion strategy. Furthermore, lasioglossins inhibited temperature‐induced morphotype changes toward hyphae and pseudohyphae with sporadic occurrence of atypical cells with two or enlarged nuclei, suggesting interference with mitosis or cytokinesis. Local application of LLIII reduced the duration of experimental candidiasis with no evidence of adverse effects. Lasioglossin LLIII is a promising candidate for development as an antimicrobial drug for treating the vaginal candidiasis.
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Plasmacytoid dendritic cells (pDCs) are a subset of dendritic cells endowed with the capacity of producing large amounts of IFNα. Here we show that the Leukocyte-Associated Ig-like Receptor-1 (LAIR-1) is abundantly expressed on pDCs (the highest expression among all leukocytes) and its cross-linking inhibits IFNα production in response to Toll-like receptor ligands. Remarkably, LAIR-1 expression in pDCs is down-regulated in the presence of interleukin (IL)-3, thus indicating coordinated functions with NKp44, another pDC inhibitory receptor, which is conversely induced by IL-3. Nevertheless, the expression of NKp44 in pDCs isolated from secondary lymphoid organs, which is thought to be influenced by IL-3, is not coupled to a decreased expression of LAIR-1. Interestingly, pDCs isolated from peripheral blood of systemic lupus erithematosus (SLE) patients express lower levels of LAIR-1 while displaying slight but consistent expression of NKp44, usually undetectable on pDCs derived from healthy donors. Using sera derived from SLE patients, we show that LAIR-1 and NKp44 display synergistic inhibitory effects on IFNα production by interleukin IL-3 cultured pDCs stimulated with DNA immunocomplexes. In conclusion, our results indicate that the inhibitory function of LAIR-1 may play a relevant role in the mechanisms controlling IFNα production by pDCs both in normal and pathological innate immune responses.  相似文献   
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