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81.
BACKGROUND: In maintenance haemodialysis patients, daily food intake is changeable; however, its relationship with nutritional status is unexplored. This study aimed to evaluate the isolated, long-term effect of daily nutrient intake on nutritional status in haemodialysis patients. METHODS: We performed a prospective 1-year controlled study in 27 chronic haemodialysis patients, without recognized risk factors for malnutrition. Each day for 1 week, four times in the year, we measured protein nitrogen appearance, and assessed dietary protein (DPI) and energy (DEI) intake from dietary diaries. We compared the nutritional outcome of patients spontaneously reducing nutrient intake below the threshold of 0.8 g/kg body weight/day for DPI and 25 kcal/kg body weight/day for DEI during the week (LOW, n = 8), with controls at adequate nutrient intake (CON, n = 19). An interventional 6-month study was then carried out in LOW to verify the cause-effect relationship. RESULTS: All patients showed a day-by-day reduction of whole nutrient intake during interdialytic period, which was mostly relevant in the third interdialytic day (L3). During the 1-year study, even in the presence of adequate dialysis dose and normal inflammatory indexes, body weight (68.0 +/- 5.5 to 65.8 +/- 5.9 kg), serum albumin (3.96 +/- 0.07 to 3.66 +/- 0.06 g/dl) and creatinine (9.2 +/- 1.1 to 8.1 +/- 0.7 mg/dl) significantly decreased in LOW but not in CON. Diaries evidenced in LOW a reduced number of meals at L3 that was explained by the fear of excessive interdialytic weight gain. During the interventional study, daily DPI and DEI increased at L3; this was associated with a significant increment of body weight, and serum albumin and creatinine levels. CONCLUSIONS: In maintenance haemodialysis patients the persistent, marked reduction of daily nutrient intake, even if limited to a single day of the week, is an independent determinant of reversible impairment of nutritional status.  相似文献   
82.
目的 制备甘草蛋白免疫磁性微球,并建立快速、精确的免疫磁性捕获ELISA法检测甘草蛋白。方法 采用种子聚合法合成聚苯乙烯磁性微球,并以兔抗甘草蛋白IgG抗体致敏,制备特异性捕获甘草特征蛋白的免疫磁性微球。以生物素标记抗体为示踪抗体,结合辣根过氧化物酶标亲和素建立ELISA检测系统,用于甘草药材和含甘草中成药中甘草蛋白的分析。结果 利用该方法对甘草药材和中成药中甘草蛋白抗原检测,检测灵敏度达到10ng/mL。结论 免疫磁性捕获ELISA检测技术方便、快速、准确,为生药的品种鉴定及中成药的质量控制提供一种新方法。  相似文献   
83.
毛喉萜对人肝癌细胞增殖影响的实验研究   总被引:1,自引:0,他引:1  
目的 探讨毛喉萜 (Forskolin)的抗肝癌作用。方法 采用克隆形成、MTT比色法观察毛喉萜对SMMC 772 1细胞的作用 ,并利用免疫细胞化学方法检测其对rasp2 1、p5 3蛋白表达的影响。结果 毛喉萜可明显抑制SMMC 772 1细胞的增殖 ,其抑制率与剂量呈正相关 (P <0 .0 1 ) ,经毛喉萜处理后 ,rasp2 1、p5 3蛋白表达均有明显下降。结论 毛喉萜能明显抑制肝癌SMMC 772 1细胞增殖 ,其作用可能与降低rasp2 1、p5 3蛋白表达有关。  相似文献   
84.
目的:制备抗醛糖还原酶(AR)的单克隆抗体(mAb),并与本室制备的抗醛糖还原酶相似蛋白(ARL-1)mAb进行比较。方法:经RT-PCR获得AR基因,将基因插入pGEX-4T-1(His)6C中,构建重组质粒pGEX-4T-1(His)6C-AR,以重组质粒转化E.coliRosetta诱导表达GST-AR蛋白。以纯化的GST-AR蛋白免疫BALB/c小鼠,采用杂交瘤技术制备mAb。应用间接ELISA和Western blot方法对mAb进行筛选和鉴定。使用Clustalx和Antheprot软件,比较AR与ARL-1的同源性,表达GST-dAR[80~142氨基酸(aa)],与ARL-1差异较大;并分析AR的抗原性,表达GST-dA1(1~79aa)、GST-dA2(80~99aa)、GST-dA3(111~142aa)、GST-dA4(143~316aa)。利用AR全长及截短蛋白,采用Western blot分析制备的抗AR mAb识别AR抗原的部位。结果:获得3株稳定分泌抗AR mAb的杂交瘤细胞系ARB3、AR7B3G4和ARF10。3株抗GST-AR的mAb均为IgG1(κ型),腹水mAb效价为1∶4×105,细胞培养上清mAb效价为1∶1×104,3株mAb均可与胎盘组织中的AR蛋白起反应,而与GST-ARL-1和GST蛋白无交叉反应。它们分别为抗GST-dA1、GST-dA3和GST-dA4蛋白的mAb。结论:成功地制备了3株特异性抗AR mAb,可分别识别AR的1~79、111~142、143~316位氨基酸。将它们与抗ARL-1mAb联合应用,将有助于进一步研究AR与ARL-1蛋白的功能,并为深入探讨AR、ARL-1与相关疾病的关系及进行大规模的流行病学调查提供了有力的工具。  相似文献   
85.
86.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
87.
目的:探讨妊娠高血压综合征(妊高征)患者血清胰岛素样生长因子(IGF-1)和胰岛素样生长因子结合蛋白-3(IGFBP-3)水平与疾病程度及新生儿出生体重之间的关系。方法:用放射免疫方法测定33例妊高征和32例正常血压妊娠妇女的血清IGF-1、IGFBP-3的水平。结果:重度妊高征组IGF-1显著低于正常组,IGFBP-3在各组间的水平浓度差异均无显著性,但IGF-1与IGFBP-3之间呈正相关。新生儿出生体重随妊高征严重程度的加剧而降低,各组间比较差异有显著性(F=5.453,P=0.002)。结论:妊高征患者的发病及严重程度与IGF-1有明显的关系,IGF-1与胎儿的发育及新生儿出生体重有明显的相关性。  相似文献   
88.
目的:探讨急性心肌梗死(AMI)、不稳定性心绞痛(UA)患者外周血中循环内皮祖细胞(EPCs)与炎性相关因子C反应蛋白质(CRP)、白细胞介素-6(IL-6)及肿瘤坏死因子-α(TNF-α)的相关性。方法:取AMI(25例)UA患者(28例)及健康体检者(对照组32例)静脉血,采用密度梯度离心法从外周血获得单个核细胞;激光共聚焦显微镜鉴定FITC-UEA-I和Dil-acLDL双染色阳性细胞为正在分化的EPCs,并在倒置荧光显微镜下计数;酶联免疫法检测各种炎性相关因子。结果:AMI组及UA组的EPCs数量和血清CRPI、L-6、TNF-α水平显著高于正常对照组。结论:AMI及UA患者EPCs数量增加与炎性相关因子增加有关。  相似文献   
89.
The cause of Alzheimer's disease is unknown. Several factors have been proposed including head trauma. At present, the link between head injury and a subsequent neurodegenerative process is largely circumstantial, except in the case of dementia pugilistica (punch drunk syndrome) found in boxers. Recent studies have shown that the brains of boxers with this syndrome contain large numbers of 'diffuse' beta-protein immunoreactive plaques. We supposed that this plaque type might be associated with trauma induced Alzheimer-like degeneration. In order to test this hypothesis we have re-investigated a previously reported case of post-traumatic premature Alzheimer's disease. Immunocytochemistry using antibodies to amyloid beta-protein revealed large numbers of 'diffuse' non-Congophilic plaques with little or no neuritic component. A similar preponderance of this plaque type is present in the brains of boxers with dementia pugilistica. Our observations support the idea of a trauma induced Alzheimer-like degenerative process and indicate that such a condition is associated with a marked preponderance of 'diffuse' plaques.  相似文献   
90.
Retinol-binding protein (RBP) is the transport protein that carries retinol in the circulation from the liver to its target tissues. The existence of a cell-surface receptor on the target cells, which mediates the uptake of retinol from RBP, has been known since 1975. Recently, it was identified as an integral transmem-brane protein named STRA6 that is inducible by retinoic acid in certain cancer cells. The receptor was found to be highly specific for RBP, with high affinity, and to be localized in all tissues known to require retinol for their function, particularly the pigment epithelium of the eye.  相似文献   
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