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101.
Elevated plasma homocysteine, an independent risk factor for cardiovascular disease (CVD) can be lowered by administration of pharmacological doses of folic acid. The effect of lower doses in apparently normal subjects is currently unknown but is highly relevant to the question of food fortification. Healthy male volunteers (n = 30) participated in a chronic intervention study (26 weeks). Folic acid supplements were administered daily at doses increasing from 100 micrograms (6 weeks), to 200 micrograms (6 weeks), to 400 micrograms (14 weeks). Fasting blood samples collected before, during and 10 weeks post intervention were analysed for plasma homocysteine, serum and red- cell folate levels. Results, expressed as tertiles of baseline plasma homocysteine concentration, showed significant (p < or = 0.001) homocysteine lowering in the top (10.90 +/- 0.83 mumol/l) and middle (9.11 +/- 0.49 mumol/l) tertiles only. In the low tertile, where the mean baseline homocysteine level was 7.07 +/- 0.84 mumol/l, no significant response was observed. Of the three folic acid doses, 200 micrograms appeared to be as effective as 400 micrograms, while 100 micrograms was clearly not optimal. There is thus a minimal level of plasma homocysteine below which folic acid has no further lowering effect, probably because an optimal folate status has been reached. A dose as low as 200 micrograms/day of folic acid is effective in lowering plasma homocysteine concentrations in apparently normal subjects. Any public health programme for lowering homocysteine levels, with the goal of diminishing CVD risk, should not be based on unnecessarily high doses of folic acid.   相似文献   
102.
The efficacy of subcutaneous recombinant human erythropoietin (rhEPO) (500 U/kg; administered twice a week during the 3 weeks before surgery) in the recovery of preoperative hemoglobin concentrations within a 3- week period was studied in 40 patients, each of whom donated 2 units (900 mL) of blood for their own use before total hip replacement surgery. Twenty autologous blood donors received rhEPO (EPO group) and 20 were not treated (control group). The initial hemoglobin concentration (14.0 +/− 1.0 g/dL [140 +/− 10 g/L]) was completely recovered before surgery (14.0 +/− 1.6 g/dL [140 +/− 16 g/L]) in the EPO group, while a decrease from 13.8 +/− 1.1 to 12.2 +/− 1.3 g per dL (138 +/− 11 to 122 +/− 13 g/L) was observed in the control group. The preoperative reticulocyte count showed more than sixfold increase in the EPO group, whereas a twofold to threefold increase was found in the control group. Serum ferritin concentration fell to 42 +/− 29 micrograms per L in the EPO group and to 54 +/− 35 micrograms per L in the control group. The postoperative serum erythropoietin concentration in the EPO group was significantly lower than that in the control group, but it did not differ from the pretreatment value and was attended by a higher hemoglobin concentration after surgery. Only transient flu-like symptoms were mentioned by patients who were treated with rhEPO. Changes in blood pressure or platelet count or other adverse events were not observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
103.
目的:观察贞芪扶正颗粒和复方阿胶浆对苯油溶液致小鼠再生障碍性贫血模型的疗效。方法:实验于2005-06/09在河南中医学院药理实验室完成。①选用昆明种成年雄性小鼠90只。按随机数字表法将小鼠分为9组,每组10只:大、中、小剂量贞芪扶正颗粒组:按15,10,5g/kg剂量灌服贞芪扶正颗粒混悬液(主要成分:黄芪、女贞子;甘肃扶正药业科技股份有限公司生产;批号040803,15g/袋)。大、中、小剂量复方阿胶浆组:分别按10,20,30mL/kg剂量灌胃复方阿胶浆(主要成分:阿胶、熟地黄、党参、山楂、人参、蔗糖;山东东阿阿胶股份有限公司生产,批号050446,250mL/瓶),司坦唑醇组:按4mg/kg剂量灌胃司坦唑醇混悬液(司坦唑醇片,广西南宁百会药业集团有限公司生产,批号050306,30mg/片)。空白组和模型组:灌胃同体积的生理盐水(20mL/kg)。每天给药1次,连续给药14d。除空白组外,其余组小鼠皮下注射体积分数0.25苯的玉米油溶液4mL/kg复制苯油溶液致小鼠再生障碍性贫血模型,空白组皮下注射同体积玉米油。②各组小鼠分别于末次给药后24h,进行血常规检测。取右侧股骨,冲出骨髓细胞,采用BI-2000医学图像分析仪计数骨髓有核细胞数。③计量资料符合正态分布、方差齐者用t检验;方差不齐者用t’检验。结果:小鼠90只均进入结果分析。①血细胞测定结果比较:模型组小鼠血红细胞、白细胞、血小板计数和血红蛋白水平明显低于空白组(t=3.39~11.89,P<0.01)。司坦唑醇组3项血细胞计数和血红蛋白水平明显高于模型组(t=4.94~6.73,P<0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血白细胞计数明显高于模型组(t=2.32~3.03,P<0.05 ̄0.01)。中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组小鼠血红细胞计数明显高于模型组(t=2.15~4.84,P<0.05 ̄0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血红蛋白水平明显高于模型组(t=2.33~4.45,P<0.05 ̄0.01)。大、中剂量贞芪扶正颗粒组和各剂量复方阿胶浆组血小板计数明显高于模型组(t=4.06~6.24,P<0.01)。②骨髓有核细胞数:模型组明显低于空白组(t=8.99,P<0.01)。司坦唑醇组、中剂量贞芪扶正颗粒组和小剂量复方阿胶浆组明显高于模型组(t=2.39~2.82,P<0.05)。结论:贞芪扶正颗粒、复方阿胶浆对皮下注射苯所致小鼠再生障碍性贫血模型血细胞状况及骨髓象均有较好的改善作用,以贞芪扶正颗粒有较为明显的剂量依赖关系。  相似文献   
104.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse.  相似文献   
105.
OBJECTIVES: In patients with compensated liver cirrhosis the clinical repercussions of detecting subclinical hepatic encephalopathy (SHE) are unclear. We present a long-term follow-up study in cirrhotic patients to examine the relationship between SHE and subsequent episodes of overt hepatic encephalopathy. METHODS: A total of 63 cirrhotic patients were studied by Number Connection Test and auditory evoked potentials. We determined glutamine, ammonia, zinc, glutamate, urea, and ratio of branched chain amino acids to aromatic amino acids, and Child-Pugh classification. RESULTS: Of 63 patients, 34 (53%) exhibited SHE. Nineteen out of 63 (30%) developed overt hepatic encephalopathy during follow-up. Hepatic encephalopathy in follow-up was related to alcoholic etiology, ammonia, glutamine, zinc, ratio of branched chain amino acids to aromatic amino acids, liver function, presence of esophageal varices, and detection of SHE (84% of patients who exhibited hepatic encephalopathy in follow-up showed SHE). In Cox-regression, glutamine levels, SHE, esophageal varices, and Child-Pugh class were the independent variables related to hepatic encephalopathy in follow-up. CONCLUSIONS: SHE (defined on the basis of number connection test or auditory evoked potentials alteration) could predict a subsequent episode of overt hepatic encephalopathy. Lower glutamine levels, presence of esophageal varices, and liver dysfunction were also related to the development of overt hepatic encephalopathy.  相似文献   
106.
The opinion of patients expressed in terms of satisfaction is extremely important in any evaluation of total knee arthroplasty (TKA) results. The primary endpoint of this study was to determine the quantitative and qualitative expectations of elderly patients before undergoing TKA. Cross-sectional study of 497 patients over 65 years was performed before TKA. Main variables collected: demographic, functioning, pain, comorbidity, depression and expectations assessed with the Hospital for Special Knee Replacement Expectation Survey. Statistical tests used were: Student's t-test, analysis of variance, Spearman's ρ and multivariate regression analysis. The means of the total and maximum expectations were 12.3 ± 1.63 and 9.5 ± 1.78 (±S.D.), respectively. Between 90 and 100% of patients referred expectations to improvement regarding pain, basic functional activities (walking, climbing stairs, knee mobility, general mobility) and general well being. There were statistically significant correlations with age (r = −0.321), pain before operation (r = −0.206), expected pain at 6 months (r = −0.206), depressive symptoms (r = −0.180) and the Barthel index (BI) (r = 0.154). One can conclude, that the expectations of improvement among patients before TKA are high and may be classified as expectations of improvement of pain, basic functional activities and general well being. Age, pain intensity and presence of depression correlate inversely with the amount of expectations.  相似文献   
107.
用于鼻腔测量的声反射技术——应用与进展   总被引:1,自引:0,他引:1  
本文综述了声反射鼻腔测量(acoustic rhinometry,AR)近年来在临床中的应用和研究。主要阐述了声反射测量的工作原理,在鼻周期以及正常人鼻腔测量相关参数建立等基础研究,在耳鼻喉科疾病诊断和药物作用等临床研究中的进展。  相似文献   
108.
109.

Problem

Poliovirus transmission remained a public health challenge in western Uttar Pradesh, India in late 2005 and early 2006. In 2006, the India Expert Advisory Group for Polio Eradication concluded that, given the peak incidence of polio among children 6 to 12 months of age, a targeted birth dose of oral polio vaccine may be necessary to interrupt intense poliovirus transmission in high risk areas.

Approach

The Government of Uttar Pradesh, the National Polio Surveillance Project and the United Nations Children’s Fund (UNICEF) implemented a pilot birth-dose project aimed at identifying and vaccinating all newborns with a dose of oral polio vaccine within 72 hours of birth in an effort to evaluate operational feasibility and potential impact on population immunity.

Local setting

The project was piloted in Moradabad district: zone 7 in Moradabad City (urban setting), Kunderki block (rural setting) and in select birthing hospitals.

Relevant changes

Between July 2006 and February 2007, 9740 newborns were identified, of which 6369 (65%) were vaccinated by project personnel within 72 hours of birth. Project coverage (for total newborns vaccinated) ranged from 39% (in zone 7) to 76% (in Kunderki block) of the estimated number of newborns vaccinated during previous supplemental immunization activities.

Lessons learned

Birth-dose coverage among newborns was lower than expected. Expansion costs were estimated to be high, with marginal impact. The project, however, provided opportunities to strengthen newborn tracking systems which have increased the number of newborns and young infants vaccinated during supplemental immunization activities and enrolled in routine programmes.  相似文献   
110.
Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method.  相似文献   
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