全文获取类型
收费全文 | 595篇 |
免费 | 31篇 |
国内免费 | 1篇 |
专业分类
627篇 |
出版年
2022年 | 8篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 18篇 |
2016年 | 15篇 |
2015年 | 31篇 |
2014年 | 44篇 |
2013年 | 40篇 |
2012年 | 63篇 |
2011年 | 58篇 |
2010年 | 35篇 |
2009年 | 25篇 |
2008年 | 32篇 |
2007年 | 28篇 |
2006年 | 31篇 |
2005年 | 27篇 |
2004年 | 17篇 |
2003年 | 19篇 |
2002年 | 16篇 |
2001年 | 17篇 |
2000年 | 11篇 |
1999年 | 16篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有627条查询结果,搜索用时 0 毫秒
11.
Seong Jin Jeong Han Sol Lee Jeong Keun Lee Jin Woo Jeong Sang Cheol Lee Jeong Hyun Kim Sung Kyu Hong Seok-Soo Byun Sang Eun Lee 《PloS one》2014,9(11)
Objectives
Mid-urethral sling (MUS) surgery for the treatment of urinary incontinence has been widespread since the introduction of tension-free vaginal tape in the mid-1990s. The majority of studies with short-term follow-up <2 years found no differences in the surgical outcomes according to body mass index (BMI). However, considering the chronic influence of obesity on pelvic floor musculature, it is cautiously speculated that higher BMI could increase stress on pelvic floor and sub-urethral tape, possibly decreasing the long-term success rate in the obese population. We aimed to compare the long-term effects of BMI on the outcomes of MUS between women with retropubic and transobturator approaches.Methods
We performed a retrospective analysis on 243 consecutive women who received MUS and were followed up for ≥36 months. The influence of BMI on the success rates was separately estimated and the factors for treatment failure were examined using logistic regression in either approach.Results
The mean follow-up was 58.4 months, and 30.5% were normal weight, 51.0% overweight, and 18.5% obese. Patients received either the retropubic (30.5%) or transobturator (69.5%) approach. The success rates (%) under the transobturator approach differed according to the BMI groups (94.3, 88.6, and 78.6, respectively; P = 0.037) while those under the retropubic approach were not different according to the BMI groups. However, in multivariate models, only the presence of preoperative mixed urinary incontinence (MUI) was proven to be the risk factor for treatment failure in the transobturator approach (OR 6.39, P = 0.003). The percent of subjects with MUI was higher in obese women than in non-obese women with the transobturator approach.Conclusions
BMI was not independently associated with failures in either approach. Higher success rates in women with lower BMI in the transobturator approach were attributed to the lower percent of preoperative MUI in those with lower BMI. 相似文献12.
Kang JH Kim YK Park JY An CM Nam MM Byun SG Lee BI Lee JH Choi TJ 《Genetics and molecular research : GMR》2011,10(4):2786-2794
An interspecific artificial hybrid was produced between two economically important aquaculture flatfish: olive flounder (Paralichthys olivaceus) and starry flounder (P. stellatus). This hybrid displays the rapid growth characteristic of the former and tolerance to low temperatures and low salinity of the latter, but the genetics of inheritance in this hybrid have not been elucidated. Polymorphic microsatellite markers developed for P. olivaceus and P. stellatus were tested to determine if these markers can be used for analysis of parentage and genetic inheritance. Multiplex PCR using two primer sets that were specific to each species produced PCR products of different sizes; these could be used for the identification of interspecific hybrids. Among the 192 primers derived from olive flounder, 25.5% of the primer sets successfully amplified genomic DNA from starry flounder, and 23% of the 56 primer sets originating from starry flounder amplified DNA from olive flounder. Analysis of genetic inheritance in the hybrid using seven of the 62 microsatellite markers common to both species demonstrated classic Mendelian inheritance of these markers in the hybrid progeny, with the exception of one locus identified as a null allele in the hybrid. These results demonstrate that cross-specific microsatellite markers can be used tools for parentage analysis of hybrid flatfish, for mapping quantitative trait loci, for marker-assisted selective breeding, and for studies of the evolution of fish. 相似文献
13.
Chung HK Kim SW Byun SJ Ko EM Chung HJ Woo JS Yoo JG Lee HC Yang BC Kwon M Park SB Park JK Kim KW 《BMB reports》2011,44(10):686-691
Granulocyte colony-stimulating factor (G-CSF) is a cytokine secreted by stromal cells and plays a role in the differentiation of bone marrow stem cells and proliferation of neutrophils. Therefore, G-CSF is widely used to reduce the risk of serious infection in immunocompromised patients; however, its use in such patients is limited because of its non-persistent biological activity. We created an N-linked glycosylated form of this cytokine, hG-CSF (Phe140Asn), to assess its biological activity in the promyelocyte cell line HL60. Enhanced biological effects were identified by analyzing the JAK2/STAT3/survivin pathway in HL60 cells. In addition, mutant hG-CSF (Phe140Asn) was observed to have enhanced chemoattractant effects and improved differentiation efficiency in HL60 cells. These results suggest that the addition of N-linked glycosylation was successful in improving the biological activity of hG-CSF. Furthermore, the mutated product appears to be a feasible therapy for patients with neutropenia. 相似文献
14.
The biological benefits of certain carotenoids may be due to their potent antioxidant properties attributed to specific physico-chemical interactions with membranes. To test this hypothesis, we measured the effects of various carotenoids on rates of lipid peroxidation and correlated these findings with their membrane interactions, as determined by small angle X-ray diffraction approaches. The effects of the homochiral carotenoids (astaxanthin, zeaxanthin, lutein, beta-carotene, lycopene) on lipid hydroperoxide (LOOH) generation were evaluated in membranes enriched with polyunsaturated fatty acids. Apolar carotenoids, such as lycopene and beta-carotene, disordered the membrane bilayer and showed a potent pro-oxidant effect (>85% increase in LOOH levels) while astaxanthin preserved membrane structure and exhibited significant antioxidant activity (40% decrease in LOOH levels). These findings indicate distinct effects of carotenoids on lipid peroxidation due to membrane structure changes. These contrasting effects of carotenoids on lipid peroxidation may explain differences in their biological activity. 相似文献
15.
16.
Se-Kwon Kim Pyo-Jam Park Won-Kyo Jung Hee-Guk Byun Eresha Mendis Young-In Cho 《Carbohydrate polymers》2005,60(4):483-487
Chitooligosaccharides (COSs) were successfully prepared using an ultrafiltration membrane bioreactor system, and named as COS-I (10–5 kDa), COS-II (5–3 kDa), COS-III (3–1 kDa), and COS-IV (below 1 kDa), respectively. In addition, their phosphorylated derivatives were prepared by a P2O5 in methanesulfonic acid solution, and inhibitory activity on the formation of insoluble calcium phosphate of phosphorylated chitooligosaccharides. Phosphorylated COS-IV exhibited the highest inhibitory activity of calcium phosphate precipitation among tested chitooligosaccharides. Its inhibitory activity, especially at the concentration more than 4 mg/ml, was similar to that of CPP, which is widely used as a calcium fortifying agent increasing calcium absorbability. Therefore, phosphorylated chitooligosaccharides may be potential inhibitors of calcium phosphate precipitation. 相似文献
17.
Sun-Ju Byun Kyung Chul Moon Kyung-Suk Suh Joon Koo Han Jong-Yil Chai 《The Korean journal of parasitology》2010,48(2):161-165
Echinococcus granulosus, an intestinal tapeworm of dogs and other canids, infects humans in its larval stage and causes human echinococcosis or hydatid disease. In the Republic of Korea, 31 parasite-proven human echinococcosis cases have been reported, most of which were imported from the Middle East. We recently examined a 61-year-old Korean man who had a large cystic mass in his liver. ELISA was negative for tissue parasitic infections, including echinococcosis, cysticercosis, paragonimiasis, and sparganosis. The patient underwent surgery to remove the cyst, and the resected cyst was processed histopathologically for microscopic examinations. In sectioned cyst tissue, necrotizing protoscolices with disintegrated hooklets of E. granulosus were found. In some areas, only freed, fragmented hooklets were detected. The patient had traveled to western and central Europe in 1996, and had no other history of overseas travel. We report our patient as a hepatic echinococcosis case which was probably imported from Europe. 相似文献
18.
Carnrot C Vogel SR Byun Y Wang L Tjarks W Eriksson S Phipps AJ 《Biological chemistry》2006,387(12):1575-1581
Bacillus anthracis, which causes anthrax, has attracted attention because of its potential use as a biological weapon. The risk of multidrug resistance against B. anthracis increases the need for antibiotics with new molecular targets. Nucleoside analogs are well-known antiviral and anticancer prodrugs, and thymidine kinase catalyzes the rate-limiting step in the activation of pyrimidine nucleoside analogs used in chemotherapy. The thymidine kinase gene from B. anthracis Sterne strain (34F2) (Ba-TK) was cloned and expressed in E. coli, and the product was purified and characterized regarding its substrate specificity. Ba-TK phosphorylated pyrimidine nucleosides and all natural nucleoside triphosphates served as phosphate donors. Size exclusion chromatography indicated a dimeric form of Ba-TK, regardless of the presence of ATP. Thymidine was the most efficient substrate with a low K(m) value (0.6 microM) and a V(max) of 3.3 micromol dTMP mg(-1) min(-1), but deoxyuridine (K(m)=4.2 microM, V(max)=4.1 micromol dUMP mg(-1) min(-1)) was also a good substrate. Several pyrimidine analogs were also tested and analogs with 5-position modifications showed higher activities compared to analogs with 3'- and N3-position modifications. Deoxyuridine analogs were the most potent inhibitors of B. anthracis growth in vitro. These results may be used to guide future development of nucleoside analogs against B. anthracis. 相似文献
19.
20.
Cho BO Jin CH Park YD Ryu HW Byun MW Seo KI Jeong IY 《Bioscience, biotechnology, and biochemistry》2011,75(7):1306-1311
Isoegomaketone (IK) is an essential oil component of Perilla frutescens (L.), but the mechanism by which IK induces apoptosis has never been studied. The purpose of this study was to elucidate the IK-induced apoptotic pathway in DLD1 human colon cancer cells. We observed that IK treatment over 24 h significantly inhibited cell viability in a dose-dependent manner. We also found that IK triggered cleavage of PARP. Moreover, IK treatment resulted in cleavage of caspase-8, -9, and -3 in a dose- and time-dependent manner. IK treatment also resulted in cleavage of Bid and translocation of Bax, and triggered the release of cytochrome c from the mitochondria to the cytoplasm. Furthermore, it resulted in the translocation of apoptosis inducing factor (AIF), a caspase-independent mitochondrial apoptosis factor, from the mitochondria into the nucleus. Overall, these results suggest that IK induces apoptosis through caspase-dependent and capase-independent pathways in DLD1 cells. 相似文献