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41.
鲍善芬  李寒濂 《营养学报》1994,16(4):401-405
对我院老年病房四季112份全膳食中的15种元素(钾、钠、钙、磷、镁、锌、铜、铁、锰、硒、铝、钴、铬、钼、镍)进行了实测。结果表明:钾的平均日摄入量为1809+38mg,接近RDA值的下限;钠的平均日摄入量为5972±146mg远高于1100~3300mg的供给标准。钙、磷、镁的日摄入量已达到了RDA值的标准。全膳食中锌、铜的含量分别为11.68±0.19mg和1.72±0.10rng,略低于RDA值(15mg及2~3mg)的标准,锰含量为3.41±0.09mg硒为98±2.5μg,都处于安全与适宜摄入范围(2.5~5.0mg和50~200μ9)。钴、铬、钼、镍均为人体必需的微量元素、目前我国尚未建立有关营养供给量标准。该项研究结果可为今后确定其推荐供给量标准提供必要的基础资料.  相似文献   
42.
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus.  相似文献   
43.
We evaluated the influence of individually estimated portion sizes on the estimate of nutrient related risk of colorectal cancer, using data from a Portuguese hospital based case-control study on diet and colorectal cancer. A total of 100 patients with colorectal adenocarcinoma (aged 15-92 years) and 211 controls (aged 36-89 years) were included. Two data sets were created for nutrient analysis, the first one allowed estimates of food intake using data on portion size as collected with visual aids during the interview. The second estimate substituted respondents' estimate with a standard portion size, as used in the semi-quantitative (SQ) food frequency approach. The two analytic approaches yielded similar energy and nutrient intakes in cases and controls. The percent range of concordance is acceptable, in the same quartile varying from 44 to 82% (mean: 56%) and very good in the same or adjacent (+/-1) quartile (mean: 91%, range: 85-97%). The two estimates lead to a similar pattern of multivariate odd's ratio, however the SQ estimates resulted in more significant findings. We conclude that little extra information is gained by including individual portion size information when assessing diet-related risk of colorectal cancer.  相似文献   
44.
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.  相似文献   
45.
骨形态计量学评价低钙对大鼠皮质骨的作用研究   总被引:2,自引:0,他引:2       下载免费PDF全文
目的 评价低钙饮食对大鼠皮质骨的影响。方法 3月龄SD普通级雄性大鼠40只,随机分为5组。第1、2组饲养1个月,分为正常对照组(1mol,ca1.0%)和极低钙组VLCD(1mol,Ca0.1%),余下3组饲养3个月,分为正常对照组(3mol,Ca1.0%)、极低钙组VLCD(3mol,Ca0.1%)和低钙组LCD(3mol,Ca0.3%)。各组动物喂养包含对应钙含量的精制饲料,处死前进行双荧光标记。实验结束时,取左侧胫骨中段行骨形态计量学检测。结果 无论是低钙饮食1个月,还是3个月,无论是极度缺钙,还是仅有轻微的钙不足,胫骨中段横截面皮质骨始终未出现显著意义的变化,但骨内膜骨吸收有增加的趋势。结论 低钙对皮质骨作用不明显,这可能与机体在低钙状态下动用骨骼的次序或快慢有关。  相似文献   
46.
目的为进一步调查太钢放射工作人员外照射剂量大小,以评价太钢近几年来放射管理和放射防护效果,降低放射危害,保护放射工作人员身体健康。方法根据GB5294-85《放射工作人员个人剂量监测方法》将1998-2002年在太钢从事放射的工作人员分为4组:医用X射线、工业X射线、工业γ射线和医用同位素组,进行外照射个人剂量监测,并计算1998-2002年各年度平均年剂量当量。每年监测4个周期,每个周期为3个月,并对监测结果进行分析。结果①5个年度平均年剂量当量为1.46mSv,1998年最高,从2000年起有逐渐下降的趋势;并且除2002年与2000、2001年比较,U检验差异无统计学意义外,其余各年度之间比较,差异均有统计学意义(P〈0.01);②1998-2002年各工种之间年个人剂量当量监测结果,以工业γ射线组均值最低,医用X射线组最高。U检验,工业γ射线组与其他3个组比较,差异有统计学意义(P〈0.01),医用X射线组与工业X射线组比较,差异亦有统计学意义;③1998-2002年各年度年个人有效剂量频数分组分布,〈1mSv/a组占受检总数的27.11%,〉5mSv/a的占0.31%,〈5mSv/a的占99.69%。经χ^2检验,各年度之间比较,差异有统计学意义(χ^2=377.33,P〈0.01);④各工种个人剂量当量分组频数分布情况:〈1mSv/a占受检总数的26.49%,1-2mSv/a组占59.89%.2-3mSv/a占10.52%,〈5mSv/a的占99.69%,〉5mSv/a仅3例,为医用X线组。各工种之间比较,χ^2检验有统计学意义(χ^2=1030.79,P〈0.001)。结论1998-2002年平均剂量当量远低于国家标准,并逐年下降,说明近5年太钢加强放射工作人员的健康和防护设施管理的工作,放射工作环境是安全的。  相似文献   
47.
The irritable bowel syndrome (IBS) is a very common disorder of intestinal function characterized by variable symptoms of abdominal pain, diarrhea, constipation and bloating. The spectrum of severity ranges from mild symptoms, not worthy of clinical attention, to intense and continuous symptoms associated with impaired health-related quality of life and high health care use. Psychosocial disturbance is commonly found among patients with irritable bowel, but until recently, its precise role in the disorder was uncertain. The data now suggest that irritable bowel is not a psychiatric disorder per se, but psychosocial factors including life stress, psychiatric comorbidity and abnormal illness behavior, among others, influence how the illness is experienced and acted upon. Patients with mild symptoms usually respond to education, reassurance, dietary modification and, when needed, antimotility agents. However, patients with more severe symptoms, who usually have greater psychosocial disturbance, will also require behavioral interventions, and possibly psychopharmacological agents. In sum, a graduated, multicomponent plan of care that includes dietary, behavioral and pharmacological treatments is recommended.  相似文献   
48.
We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann’s 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann’s 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer’s effect and the gamut expansion effect are just different names for the same basic phenomenon.  相似文献   
49.
目的 观察X线电视引导下经皮穿刺腰椎间盘切吸术治疗腰椎间盘突出症的远期疗效。方法 32例经CT扫描证实的腰椎间盘突出症患者,其中,膨出型29例,游离型2例,以及突出型1例,均经X线电视引导下经皮穿刺腰椎间盘切吸术治疗,术后均经随访0.5~11.0a。结果 术后1周~3个月,32例中的24例临床症状与体征得到有效控制或明显减轻,随访5~11a观察表明,症状完全消失和明显减轻者分别见于23例和6例,总有效率90.6%,预后极好和较好者均见于膨出型腰椎间盘突出症患者。结论 游离型和突出型腰椎间盘突出症的疗效均不理想,因此,术前认真选择适应证是获得理想疗效的关键性因素。  相似文献   
50.
吡格列酮对高脂饮食兔主动脉LOX-1表达的影响   总被引:2,自引:0,他引:2  
目的探讨吡格列酮对高脂饮食下兔主动脉LOX-1表达的影响及其对动脉粥样硬化的作用。方法设立正常饮食、高脂饮食及高脂饮食加吡格列酮干预3组,通过比较主动脉病理形态学改变、血脂的变化、LOX-1分子及mRNA的表达进行研究,采用免疫组化检测兔主动脉LOX-1分子的表达,采用RT-PCR检测LOX-1mRNA的表达。结果吡格列酮能减轻高脂饮食所致的内膜增厚和平滑肌增生,减轻高脂血症所致动脉粥样硬化的发展。吡格列酮还能明显升高HDL,对TC、LDL、TG和BS无明显影响。高脂饮食刺激兔主动脉LOX-1分子及mRNA的表达,吡格列酮能显著减轻这种作用。结论吡格列酮能减轻高脂饮食兔主动脉LOX-1分子及mRNA的表达,这可能是噻唑烷酮类药物抗动脉粥样硬化的重要作用机制。  相似文献   
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