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261.
In this study, we investigate whether arsenite-induced DNA damage leads to p53-dependent premature senescence using human glioblastoma cells with p53-wild type (U87MG-neo) and p53 deficient (U87MG-E6). A dose dependent relationship between arsenite and reduced cell growth is demonstrated, as well as induced γH2AX foci formation in both U87MG-neo and U87MG-E6 cells at low concentrations of arsenite. Senescence was induced by arsenite with senescence-associated β-galactosidase staining. Dimethyl- and trimethyl-lysine 9 of histone H3 (H3DMK9 and H3TMK9) foci formation was accompanied by p21 accumulation only in U87MG-neo but not in U87MG-E6 cells. This suggests that arsenite induces premature senescence as a result of DNA damage with heterochromatin forming through a p53/p21 dependent pathway. p21 and p53 siRNA consistently decreased H3TMK9 foci formation in U87M G-neo but not in U87MG-E6 cells after arsenite treatment. Taken together, arsenite reduces cell growth independently of p53 and induces premature senescence via p53/p21-dependent pathway following DNA damage. [BMB Reports 2014; 47(10): 575-580]  相似文献   
262.
Ungulate reproductive success (calf production and survival) influences population performance. The moose (Alces alces) population in northeastern Minnesota, USA, has declined 65% from 2006 to 2018 but has begun to stabilize. Because causes of this decline were largely unknown, we investigated production, survival, and cause-specific mortality of calves of the global positioning system (GPS)-collared females in this population. In 2013 and 2014, we GPS-collared 74 neonates and monitored them for survival. In 2015 and 2016, we monitored 50 and 35 calving females for signs of neonatal mortality using changes in adult female velocities and assessed seasonal calf survival by aerial surveys. In 2013 and 2014 (pooled), survival to 9 months was 0.34 (95% CI = 0.23–0.52) for collared calves, and in 2015 and 2016 (pooled) survival was 0.35 (95% CI = 0.26–0.48) for uncollared calves. Mortality in all 4 years was high during the first 50 days of life. In 2013 and 2014 (pooled), calving sites were relatively safe for collared neonates; predator-kills occurred a median 17.0 days after departure and a median 1,142 m from calving sites. Predation was the leading cause of death of collared calves (84% of mortalities), with wolves (Canis lupus) accounting for 77% of these. Other forms of mortality for collared and uncollared calves included drowning, infection, vehicle collision, and natural abandonment. We documented higher wolf predation than other recent studies with similar predator communities. Identifying specific causes of calf mortality and understanding their relations to various landscape characteristics and other extrinsic factors should yield insight into mechanisms contributing to the declining moose population in northeastern Minnesota and serve as a basis for ecologically sound management responses. © 2019 The Wildlife Society.  相似文献   
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ABSTRACT Understanding survival of and factors that may predispose newborn deer (Odocoileus spp.) to mortality contribute to improved understanding of population dynamics. We captured free-ranging white-tailed deer neonates (n = 66) of radiocollared females that survived severe (Winter Severity Index [WSI] = 153) and mild (WSI = 45) winters 2000–2001 and 2001–2002. Mean dates of birth (26 May ± 1.7 [SE] days and 26 May ± 1.3 days) and estimated birth-masses of 2.8 ± 0.1 kg and 3.0 ± 0.1 kg were similar between springs 2001 (n = 31) and 2002 (n = 35), respectively. Neonate survival was similar between years; pooled mortality rates of neonates were 0.14, 0.11, and 0.20 at 0–1 weeks, 2–4 weeks, and 5–12 weeks of age, respectively, and overall survival rate for neonates to 12 weeks of age was 0.47. Predation accounted for 86% of mortality; the remaining 14% of deaths were attributed to unknown causes. Black bears (Ursus americanus) were responsible for 57% and 38% of predation of neonates in springs 2001 and 2002, respectively, whereas bobcats (Felis rufus) accounted for 50% in 2002. Wolves (Canis lupus) accounted for only 5% of predator-related deaths. Low birth-mass, smaller body size, and elevated concentrations of serum urea nitrogen (26.1 ± 2.6 mg/dL vs 19.3 ± 0.8 mg/dL) and tumor necrosis factor-α (82.6 ± 78.6 pg/mL vs. 2.3 ± 0.5 pg/mL) were associated with neonates that died within 1 week of birth. Even though we did not detect a direct relation between winter severity and birth or blood characteristics of neonates, evidence suggests that birth-mass and key serum indices of neonate nutrition were associated with their early mortality. Thus, managers can make more informed predictions regarding survival and cause-specific mortality of fawns and adjust management strategies to better control deer population goals.  相似文献   
265.
目的:比较先兆早产、胎膜早破、妊娠期糖尿病及正常妊娠女性阴道菌群分布情况。方法:选择2016年6月至2018年6月在苏州大学附属第二医院妇产科住院的妊娠女性806例,其中先兆早产组206例,胎膜早破组234例,妊娠期糖尿病组156例,正常妊娠组210例。记录四组女性异常阴道菌群检出率及异常阴道菌群分布情况。结果:四组女性的年龄、孕周比较无统计学差异(P>0.05)。先兆早产组、胎膜早破组异常阴道菌群检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),而妊娠期糖尿病组、正常妊娠组异常阴道菌群检出率比较无统计学差异(P>0.05)。先兆早产组、妊娠期糖尿病组白色假丝酵母菌检出率高于胎膜早破组、正常妊娠组(P<0.05),先兆早产组、胎膜早破组阴道加德纳菌检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),先兆早产组无乳链球菌检出率高于胎膜早破组、妊娠期糖尿病组、正常妊娠组(P<0.05),胎膜早破组大肠埃希菌检出率高于先兆早产组、妊娠期糖尿病组、正常妊娠组(P<0.05)。结论:妊娠女性阴道感染以白色假丝酵母菌、大肠埃希菌、无乳链球菌、阴道加德纳菌为主,且先兆早产、胎膜早破女性阴道致病菌感染率较高,妊娠期糖尿病女性阴道白色假丝酵母菌的感染率较高。  相似文献   
266.
ContextPremature ventricular contractions (PVCs) originating in the right ventricular outflow tract (RVOT) are traditionally considered idiopathic and benign. Echocardiographic conventional measurements are typically normal.AimsTo assess whether right ventricle longitudinal strain, determined by two-dimensional speckle tracking echocardiography, differ between RVOT PVCs patients (treated with catheter ablation) and healthy controls.MethodsWe retrospectively selected patients with PVCs from the RVOT who underwent electrophysiological study and catheter ablation between 2016 and 2019. Patients with documented structural heart disease were excluded. Transthoracic echocardiography was performed and right ventricle global longitudinal strain (RV-GLS), free wall longitudinal strain (RVFW-LS) and left ventricle global longitudinal strain (LV-GLS) were determined as well as conventional ultrasound measurements of RV and LV function.ResultsWe studied 21 patients with RVOT PVCs and 13 controls. Patients with PVCs from the RVOT had lower values of RV-GLS and RVFW-LS compared with the control group (?19.4% versus ?22.5%, P = 0.015 and ?22.1% versus ?25.5, P = 0.041, respectively). They also had lower values of LV-GLS, although still within the normal range (?19.1% versus ?20.9%, P = 0.047). Regarding RVOT PVCs patients only, RV-GLS and RVFW-LS had no correlation with the PVCs burden prior to catheter ablation and they did not differ between the patients in whom the catheter ablation was successful and those in whom it was not. RV-GLS also had a positive correlation with RVOT proximal diameter (r = 0.487, P = 0.025).ConclusionsIn this group of RVOT PVCs patients, we found worse RV longitudinal strain values (and therefore sub-clinical myocardial dysfunction) when compared to healthy controls.  相似文献   
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