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251.
Atlantic salmon Salmo salar L. (Salmonidae) were experimentally infected with Spironucleus barkhanus (Diplomonadida: Hexamitidae). Parasites were found in the blood 1 to 8 wk after infection, after which they disappeared from the blood and were found mainly in the internal organs (e.g. spleen and liver), eye socket or muscles. Mortality (38 out of 40 infected fish) occurred when fish had lesions in internal organs and/or on the body surface. Uninfected fish cohabiting with infected fish became infected after 4 wk, indicating direct transmission. There was no difference in susceptibility to spironucleosis between 3 different families of Atlantic salmon. All families developed the disease with a similar pattern of parasitaemia in the blood, similar clinical signs and gross pathology, and with very high mortality (29 out of 30). Clinical signs of systemic spironucleosis may include anemia, skin blisters, muscle ulcerations or unilateral exophthalmia. Gross pathologies include hemorrhaging of internal organs, splenomegaly or deformed (globulated) spleen, or granulomatous lesions in the spleen and liver. 相似文献
252.
253.
Shan Liang Jiang Tao Ci Leilei Liu Zhenni Lv Xiongwen Li Jun 《Molecular and cellular biochemistry》2020,463(1-2):91-100
Molecular and Cellular Biochemistry - Baicalin (BAI), a sort of flavonoid monomer, acquires from Scutellaria baicalensis Georgi, which was forcefully reported in diversified ailments due... 相似文献
254.
Karacan MS Yakan C Yakan M Karacan N Zharmukhamedov SK Shitov A Los DA Klimov VV Allakhverdiev SI 《Biochimica et biophysica acta》2012,1817(8):1229-1236
255.
Nucleoid-associated proteins are bacterial proteins that are responsible for chromosomal DNA compaction and global gene regulation. One such protein is Escherichia coli Histone-like nucleoid structuring protein (H-NS) which functions as a global gene silencer. Whereas the DNA-binding mechanism of H-NS is well-characterized, its paralogue, StpA which is also able to silence genes is less understood. Here we show that StpA is similar to H-NS in that it is able to form a rigid filament along DNA. In contrast to H-NS, the StpA filament interacts with a naked DNA segment to cause DNA bridging which results in simultaneous stiffening and bridging of DNA. DNA accessibility is effectively blocked after the formation of StpA filament on DNA, suggesting rigid filament formation is the important step in promoting gene silencing. We also show that >1 mM magnesium promotes higher order DNA condensation, suggesting StpA may also play a role in chromosomal DNA packaging. 相似文献
256.
Hazman Ömer Sarıova Ayşenur Bozkurt Mehmet Fatih Ciğerci İbrahim Hakkı 《Molecular and cellular biochemistry》2021,476(1):349-360
Molecular and Cellular Biochemistry - Arbutin is one of the active ingredients employed in cosmetics as a skin whitening agent. In the present study, the possible effects of arbutin on breast... 相似文献
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258.
Du HJ Tang N Liu BC You BR Shen FH Ye M Gao A Huang Cs 《Molecular and cellular biochemistry》2006,287(1-2):79-89
Treatment of cells with carcinogen Benzo[a]pyrene (B[a]P) allows cells to evade G1 arrest and induces cells abnormal proliferation. However, the mechanisms of its action at cellular level are not well understood. To address this question, normal human embryo lung diploid fibroblasts (HELF) were selected in the present study. We found that exposure of cells with 2.5 μM of B[a]P for 24 h resulted in a decrease of G1 population by 11.9% (P < 0.05) and a increase of S population by 17.2% (P < 0.05). Treatment of cells with B[a]P also caused dose-related activation of MAPK and induction of cyclin D1 protein expression, whereas the CDK4 protein levels were not significantly affected by B[a]P. Overexpression of cyclin D1 protein stimulated by B[a]P was significantly inhibited by 50 μM AG126 (an inhibitor of ERK1/2), but not by 25 μM SP600125 (an inhibitor of JNK1/2) or 5 μM SB203580 (an inhibitor of p38 mapk), suggesting that B[a]P-induced cyclin D1 expression was only regulated by ERK1/2 pathway. However, AG126, SP600125 or SB203580 led to cell cycle significantly arrested in G1 phase, indicating that ERK1/2, JNK1/2 and p38 mapk pathways are all required for B[a]P-induced G1/S transition. In addition, HELF cells transfecting with antisense cyclin D1 cDNA or antisense CDK4 cDNA showed significantly G1 arrest after B[a]P stimulation. These results suggested that B[a]P exposure accelerated the G1→S transition by activation of MAPK signaling pathways. Cyclin D1 and CDK4 are rate-limiting regulators of the G1→S transition and expression of cyclin D1 is predominantly regulated by ERK1/2 pathway in HELF cells. 相似文献
259.
Purpose
The role of spot sign on computed tomography angiography (CTA) for predicting hematoma expansion (HE) after primary intracerebral hemorrhage (ICH) has been the focus of many studies. Our study sought to evaluate the predictive accuracy of spot signs for HE in a meta-analytic approach.Materials and Methods
The database of Pubmed, Embase, and the Cochrane Library were searched for eligible studies. Researches were included if they reported data on HE in primary ICH patients, assessed by spot sign on first-pass CTA. Studies with additional data of second-pass CTA, post-contrast CT (PCCT) and CT perfusion (CTP) were also included.Results
18 studies were pooled into the meta-analysis, including 14 studies of first-pass CTA, and 7 studies of combined CT modalities. In evaluating the accuracy of spot sign for predicting HE, studies of first-pass CTA showed that the sensitivity was 53% (95% CI, 49%–57%) with a specificity of 88% (95% CI, 86%–89%). The pooled positive likelihood ratio (PLR) was 4.70 (95% CI, 3.28–6.74) and the negative likelihood ratio (NLR) was 0.44 (95% CI, 0.34–0.58). For studies of combined CT modalities, the sensitivity was 73% (95% CI, 67%–79%) with a specificity of 88% (95% CI, 86%–90%). The aggregated PLR was 6.76 (95% CI, 3.70–12.34) and the overall NLR was 0.17 (95% CI 0.06–0.48).Conclusions
Spot signs appeared to be a reliable imaging biomarker for HE. The additional detection of delayed spot sign was helpful in improving the predictive accuracy of early spot signs. Awareness of our results may impact the primary ICH care by providing supportive evidence for the use of combined CT modalities in detecting spot signs. 相似文献260.
To determine how single nucleotide polymorphisms (SNPs) in the hypoxia inducible factor-1α (HIF-1α) gene coding regions affect gastric cancer, the authors conducted an association study of the HIF-1α polymorphisms C1772T and G1790A for a Tibet population. DNA was extracted from peripheral blood of 87 gastric cancer patients and 106 controls and analyzed using the polymerase chain reaction/ligase detection reaction test for HIF-1α polymorphisms. There was a significant increase in the frequency of the GA 1790 genotype in patients with gastric cancer compared with healthy controls (OR 2.93; 95% CI 1.06–8.06). The genotype frequency of the HIF-1α G1790A allele A is higher in gastric cancer groups than in controls (OR 2.78; 95% CI 1.03–7.45). As for the C1772T polymorphism, no positive correlation was found between gastric cancer patients and controls (P = 0.06). Our results suggest that the HIF-1α G1790A polymorphism may be associated with gastric cancer in Tibetans. 相似文献