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51.
52.
钱塘江河口滩涂围垦区农田小型兽类群落结构的初步研究   总被引:1,自引:0,他引:1  
1987年8月和1989年8月,作者根据钱塘江河口滩涂不同年份进行围垦农田的土壤特性和不同农作物的生长地的条件,选择7个不同的样区,调查各样区内小型兽类的群落组成和数量比例,划分相应的群落,群落中的相似性指数以群落C与D最高,多样性指数和均匀度指数以群落E最高。黄毛鼠的分布与土壤的盐度及有机质C/N值之间有极显著的相关性。  相似文献   
53.
Ureteral ligation causes tubulointerstitial nephropathy characterized by the tubular dilatation, the interstitial expansion, and a leukocyte infiltration into the tubulointerstitium. The present study was designed to explore whether zinc (Zn) deficiency affects the development of unilateral ureteral obstruction (UUO)-induced tubulointerstitial nephropathy. Compared to rats fed a standard diet, rats fed a Zn-deficient diet exhibited a greater influx of leukocytes into the tubulointerstitium of the cortex of the obstructed kidney 3 d following UUO. Furthermore, rats fed a Zn-deficient diet showed a slight invasion of leukocytes into the tubulointerstitium of the cortex of the contralateral nonobstructed kidney (CLK), although there was no infiltration of leukocytes into the CLK of rats fed a standard diet. These histological changes, however, were ameliorated by administration of enalapril, an angiotensin (ANG) I-converting enzyme inhibitor. Thus, it is suggested that Zn deficiency aggravates UUO-induced tubulointerstitial nephropathy via an increase in the action of ANG II.  相似文献   
54.
目的 通过采用耻骨后膀胱颈和会阴途径球部尿道部分结扎两种方法,建立雄性大鼠膀胱出口部分梗阻(paritial bladder outlet obstraction,pBOO)模型,并对所建模型进行鉴定和比较,为pBOO后膀胱重构(bladder reconstruction)的深入研究提供一种成活率高,复制性和稳定性较好的动物模型.方法 80只健康雄性Wistar大鼠随机分为三组:I组为假手术组(对照组),20只;II组为耻骨后途径膀胱颈部分结扎组,30只;III组为会阴途径球部尿道部分结扎组,30只.依据梗阻时间分别将I组、II组、III组大鼠随机分为2周组和4周组,于术后2周和4周对大鼠行尿动力学检测后,完整切除膀胱测其重量,将精囊腺组织和部分膀胱用4%甲醛固定,HE染色观察组织学变化.结果 II组和III组成活率分别为73.3%和80.0%,二者无统计学意义;I组、II组、III组建模手术时间分别为(9.75±2.29)、(17.33±3.54)、(10.77±2.44)min,II组与I组和III组比较差异均有统计学意义;I组、II组、III组的2周组和4周组逼尿肌漏尿点压(detrusor leak point pressure,DLPP)分别为(26.31±2.32)、(27.34±3.93)、(24.68±2.39)mmHg和(26..42±2.41)、(34.23±3.01)、(32.63±3.20)mmHg,I组与II组和III组的4周组比较差异有统计学意义,II组和III组的2周组和4周组比较差异均有统计学意义.结论 耻骨后途经膀胱颈部分结扎和会阴途径球部尿道部分结扎两种方法都能成功建立雄性大鼠pBOO模型,与耻骨后途径相比,会阴途径成活率高,手术操作时间短,复制性和稳定性好.  相似文献   
55.
In patients with end-stage heart failure (HF), a total artificial heart (TAH) may be implanted as a bridge to cardiac transplant. However, in congenital heart disease (CHD), the malformed heart presents a challenge to TAH implantation. In the case presented here, a 17 year-old patient with congenital transposition of the great arteries (CCTGA) experienced progressively worsening HF due to his congenital condition. He was hospitalized multiple times and received an implantable cardioverter defibrillator (ICD). However, his condition soon deteriorated to end-stage HF with multisystem organ failure. Due to the patient''s grave clinical condition and the presence of complex cardiac lesions, the decision was made to proceed with a TAH. The abnormal arrangement of the patient''s ventricles and great arteries required modifications to the TAH during implantation.With the TAH in place, the patient was able to return home and regain strength and physical well-being while awaiting a donor heart. He was successfully bridged to heart transplantation 5 months after receiving the device. This report highlights the TAH is feasible even in patients with structurally abnormal hearts, with technical modification.  相似文献   
56.
Previously, we reported about the effectiveness of the EMOST (Electro-Magnetic-Own-Signal-Treatment) treatments in reduction of phantom limb pain as well as improvement of the quality of sleep and mood in subjects under clinical circumstances. We also presented the successful application of EMOST for mental stress management of humans under catastrophic conditions. Our some years experience indicated that the efficiency of EMOST is much greater in children than in adult subjects. In addition, in children much less treatment is needed for recovery compared to adult subjects, as well as the duration of the treatment is shorter. It is possible that this particular success is due to the large plasticity of the central and the autonomic nervous system in young patients. Thus, our research pays special attention regarding the EMOST effectiveness in the field of chronic childhood diseases. Here we report about results of routine alternative treatments carried out at Biolabor Biophysics and Laboratory Services Ltd. by EMOST device regarding to the elimination of chronic constipation and persistent diarrhea in the case of two children. We also briefly present two important possible biological mechanisms such as redox processes and the bidirectional communication between skin cells and the nervous system regarding the efficiency of low-frequency and low-intensity electromagnetic fields (LFI-EMF) treatments.  相似文献   
57.
Kidney fibrosis is a common feature of chronic kidney disease (CKD). A recent study suggests that abnormal Notch signaling activation contributes to the development of renal fibrosis. However, the molecular mechanism that regulates this process remains unexplored. Unilateral ureteral obstruction (UUO) or sham-operated C57BL6 mice (aged 10 weeks) were randomly assigned to receive dibenzazepine (DBZ, 250 μg/100 g/d) or vehicle for 7 days. Histologic examinations were performed on the kidneys using Masson's trichrome staining and immunohistochemistry. Real-time PCR and western blot analysis were used for detection of mRNA expression and protein phosphorylation. The expression of Notch 1, 3, and 4, Notch intracellular domain (NICD), and its target genes Hes1 and HeyL were upregulated in UUO mice, while the increase in NICD protein was significantly attenuated by DBZ. After 7 days, the severity of renal fibrosis and expression of fibrotic markers, including collagen 1α1/3α1, fibronectin, and α-smooth muscle actin, were markedly increased in UUO compared with sham mice. In contrast, administration of DBZ markedly attenuated these effects. Furthermore, DBZ significantly inhibited UUO-induced expression of transforming growth factor (TGF)-β, phosphorylated Smad 2, and Smad 3. Mechanistically, Notch signaling activation in tubular epithelial cells enhanced fibroblast proliferation and activation in a coculture experiment. Our study provides evidence that Notch signaling is implicated in renal fibrogenesis. The Notch inhibitor DBZ can ameliorate this process via inhibition of the TGF-β/Smad2/3 signaling pathway, and might be a novel drug for preventing chronic kidney disease.  相似文献   
58.
The success of clinical proteome analysis should be assessed based on the clinical impact following implementation of findings. Although there have been several technological advancements in mass spectrometry in the last years, these have not resulted in similar advancements in clinical proteomics. In addition, application of proteomic biomarkers in clinical diagnostics and practical improvement in the disease management is extremely rare. In this review, we discuss the relevant issues associated with identification of robust biomarkers of clinical value. Urine appears to be an ideal source of biomarkers, for theoretical, methodological, and practical reasons. Therefore, this review is focused on the search for biomarkers in urine within the last decade. Urine can be used for non-invasive assessment of a variety of diseases including those affecting the urogenital tract and also other pathologies such as cardiovascular disease or appendicitis. We also discuss the importance of data validation, an essential step in translating biomarkers into the clinical practice. Furthermore, we examine several examples of apparently successful proteomic biomarker discovery studies and their implications for disease diagnosis, prognosis, and therapy evaluation. We also discuss some current challenges in this field and reflect on future research prospects. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge.  相似文献   
59.
目的:探讨依那普利对大鼠单侧输尿管梗阻再通模型肾脏纤维化的影响.方法:18只SD大鼠随机分为两组:假手术组(6只)以及单侧输尿管梗阻模型组(12只).输尿管梗阻3天后,实施梗阻再通手术,再将大鼠随机分为模型组(6只)以及依那普利组(6只),术后,依那普利组给予依那普利灌胃10mg/kg/d,假手术组以及模型组给予等量0.5%CM-CNa溶液灌胃.用药2周后,取术侧肾组织做HE染色,并采用Raford评分系统对肾间质损伤程度进行评分;用Real-timePCR方法检测Ⅰ、Ⅲ型胶原以及CT-GFmRNA的表达;用Westemblot方法检测CTGF蛋白水平的表达.结果:模型组大鼠肾脏损伤程度,Ⅰ、Ⅲ型胶原mRNA表达水平,以及CTGFmRNA和蛋白表达水平均比假手术组明显上升(P<0.01).经依那普利治疗后,与模型组相比,以上指标均显著下降(P<0.01).结论:依那普利能有效阻止大鼠单侧输尿管梗阻再通后肾脏纤维化的进展.依那普利抗纤维化的作用机制可能与抑制CTGF的表达有关.  相似文献   
60.
婴儿痉挛症脑干信息传导障碍的混沌学研究   总被引:7,自引:2,他引:5  
婴儿痉挛症(Infantile Spasms,IS)是婴幼儿难治性癫痫。IS的发病机理至今也不清楚,目前比较一致的假说是:脑干是IS的责任结构,但该假说不能用神经生理学的传统方法来证实。从信息学的角度,婴儿弃挛症的发病机制可能是源自脑干神经信息传递障碍的脑干功能失调,为了证实这一论点,用可以反遇脑干传导功能的听觉诱发响应的相关维数,来评估脑干神经信息传导不同的功能状态,经过对IS患者、颞叶癫痫患者和健康人三个组的结果比较分析,表明IS患者脑干听觉诱发响应的相关维数明显低下,而颞叶癫痫患者该相关维数在颞叶病灶处最低。以上结果,证实了IS患者脑干神经信息传导功能障碍的存在。  相似文献   
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