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71.
BACKGROUND: An improved long-term retention of verbal memory was observed after an acute D-amphetamine administration. It was proposed that D-amphetamine modulates consolidation, but a possible drug effect on retrieval could not be rejected. OBJECTIVES: We want to provide additional support for the consolidation hypothesis, and investigate whether an influence on intervening retrieval can be refuted. METHODS: Thirty-six male paid volunteers participated in a double blind, counterbalanced, placebo-controlled design in which the number of intermediate free recall tests was manipulated. RESULTS: A significant D-amphetamine facilitation effect on recall performance emerged 1 h and 1 day after list learning. In line with the consolidation hypothesis, no effect was found on immediate tests. Importantly, the number of intermediate retrievals did not affect the magnitude of the drug effect, suggesting that the D-amphetamine facilitation effect is independent of retrieval. CONCLUSION: The D-amphetamine facilitation effect on verbal memory does not involve a modulation of the initial encoding or short-term memory (STM) processes. Moreover, the drug does not enhance long-term retention by acting on intervening retrieval processes. The current findings are in line with the conjecture of an involvement of the consolidation process in the D-amphetamine facilitation effect on verbal memory in healthy humans.  相似文献   
72.

Purpose

Based on previous studies that demonstrated the safety profile and preliminary clinical activity of prostate specific antigen (PSA) targeted therapeutic vaccines, as well as recent laboratory data supporting the value of the addition of co-stimulatory molecules B7-1, ICAM-1, and LFA-3 (designated TRICOM?) to these vaccines, we conducted a Phase I study to evaluate the safety and immunogenicity of a novel vaccinia and fowlpox vaccine incorporating the PSA gene sequence and TRICOM.

Methods

In this study, ten patients with androgen independent prostate cancer with or without metastatic disease were enrolled. Patients were treated with 2 × l08 pfu of a recombinant vaccinia virus vaccine (PROSTVAC-V) followed by 1 × 109 pfu of the booster recombinant fowlpox virus (PROSTVAC-F) both with gene sequences for PSA and TRICOM. The mean age of patients enrolled in the study was 70 (range 63 to 79). The mean PSA at baseline was 434 (range 9 – 1424).

Results

There were no deaths, and no Grade 3 or 4 adverse events. The most commonly reported adverse events, regardless of causality, were injection site reactions and fatigue. One serious adverse event (SAE) occurred that was unrelated to vaccine; this patient developed progressive disease with a new sphenoid metastasis. PSA was measured at week 4 and week 8. Four patients had stable disease (with less than 25% increase in PSA) through the week 8 study period. Anti-PSA antibodies were not induced with therapy: however, anti-vaccinia titers increased in all patients.

Conclusion

This study demonstrated that vaccination with PROSTVAC-V and PROSTVAC-F combined with TRICOM is well-tolerated and generated an immune response to vaccinia. Therefore, PROSTVAC-VF/TRICOM represents a feasible therapeutic approach for further phase II and III study in patients with prostate cancer.  相似文献   
73.

Objectives

To analyze the concept of “case series” in the medical literature compared with case reports.

Methods

A PubMed search for articles published during 2009 which had “case series” in their title was performed. A total number of 621 articles were retrieved. 586 papers were included in the analysis and 35 were excluded (18 were commentary letters, 5 were not in English, and twelve could not be retrieved by our Library). The number of patients and category of these articles were analyzed.

Results

The median (range) of the number of cases of articles having “case series” in their title was 7 (1–6432) cases. 186/ 586 articles had less than 5 cases (31.7%, 95% CI (28.3–35.1%)). The median (range) of the number of cases of articles having “case report” as their publication type was 4 (1–178) cases. Out of the 219 articles categorized as case reports 114 (52.1%, 95% CI (45.6–58.6%)) had less than five cases.

Conclusions

The concept of “case series” is not well defined in the literature and does not reflect a specific research design. We suggest that a case series should have more than four patients while four paitents or less should be reported individually as case reports.  相似文献   
74.
目的:用HPLC和电荷转移络合UV法分别测定特非那丁粒剂的含量,并对测定结果进行比较,方法:HPLC法,色谱柱:SpherisorbC8(150*4.6mm,5μm);流动相:甲醇-0.1mol/L三乙胺磷酸缓冲液(80:20),检测波长235nm。电荷转移络合UV法,利用碘与TFN在氯仿中形成电荷转移络合物的原理,在紫外294nm的波长处测定TFN的含量。结果:两法测定的线性范围和平均回收率分别  相似文献   
75.
Mycosis fungoides and Sézary syndrome are the most common variants of the cutaneous T‐cell lymphomas. Assessment of a patient with a suspected diagnosis requires thorough history taking and physical examination, in combination with skin biopsy. In some cases flow cytometry, molecular studies and imaging are also required in order to diagnose and stage the disease. Staging is derived from the tumour‐node‐metastasis‐blood classification and is currently our best attempt to stratify prognosis and hence guide management in this complex disease. Many other clinical, biological and pathological factors may help to distinguish groups at risk and predict prognosis more accurately. Management remains heavily guided by staging, such that patients with early‐stage disease generally begin treatment with skin‐directed or local therapies and those with advanced‐stage disease have many treatment options, including chemotherapy, the use of biological agents, local and total body radiotherapy, as well as haematopoietic stem cell transplantation. Besides staging, many other patient‐related factors influence the treatment strategy, particularly where symptom relief is paramount. There are many challenges remaining in the study of Mycosis fungoides and Sézary syndrome and, given the rarity of the disease, concerted worldwide efforts are required to conduct efficient and effective research.  相似文献   
76.
77.
78.

Introduction

Hyperglycemia in children after cardiac surgery can be treated with intensive insulin therapy, but hypoglycemia is a potential serious side effect. The aim of this study was to investigate the effects of reducing glucose intake below standard intakes to prevent hyperglycemia, on blood glucose concentrations, glucose kinetics and protein catabolism in children after cardiac surgery with cardiopulmonary bypass (CPB).

Methods

Subjects received a 4-hour low glucose (LG; 2.5 mg/kg per minute) and a 4-hour standard glucose (SG; 5.0 mg/kg per minute) infusion in a randomized blinded crossover setting. Simultaneously, an 8-hour stable isotope tracer protocol was conducted to determine glucose and leucine kinetics. Data are presented as mean ± SD or median (IQR); comparison was made by paired samples t test.

Results

Eleven subjects (age 5.1 (20.2) months) were studied 9.5 ± 1.9 hours post-cardiac surgery. Blood glucose concentrations were lower during LG than SG (LG 7.3 ± 0.7 vs. SG 9.3 ± 1.8 mmol/L; P < 0.01), although the glycemic target (4.0-6.0 mmol/L) was not achieved. No hypoglycemic events occurred. Endogenous glucose production was higher during LG than SG (LG 2.9 ± 0.8 vs. SG 1.5 ± 1.1 mg/kg per minute; P = 0.02), due to increased glycogenolysis (LG 1.0 ± 0.6 vs. SG 0.0 ± 1.0 mg/kg per minute; P < 0.05). Leucine balance, indicating protein balance, was negative but not affected by glucose intake (LG -54.8 ± 14.6 vs. SG -58.8 ± 16.7 μmol/kg per hour; P = 0.57).

Conclusions

Currently recommended glucose intakes aggravated hyperglycemia in children early after cardiac surgery with CPB. Reduced glucose intake decreased blood glucose concentrations without causing hypoglycemia or affecting protein catabolism, but increased glycogenolysis.

Trial registration

Dutch trial register NTR2079.  相似文献   
79.
倾斜试验中真假阳性的血流动力学和神经激素的研究   总被引:3,自引:0,他引:3  
目的探讨血管迷走性晕厥患者和正常人倾斜试验阳性时不同的触发机制.方法倾斜试验采用静息平卧10min和80°直立30min.心脏监测仪连续监测心率和血压.试验阳性标准为晕厥先兆伴收缩压<90imHg(1mmHg=O.133kPa)和(或)心率<60次/min.超声心动图于基础平卧,直立2min和每隔3min直至试验结束时连续记录左室内径及降低速率,左室短轴缩短分数(SF)和每分心输出量(CO).同时测量平卧和直立时儿茶酚胺血浆浓度.试验分组为正常自愿者且倾斜试验阴性者8例(组1),平均年龄(34±5)岁;正常自愿者伴倾斜试验阳性者8例(组2),平均年龄(31±6)岁;原因不明晕厥伴倾斜试验阳性者16例(组3),平均年龄(30±9)岁.结果三组间年龄、性别以及基础状态下心率,平均动脉压、左室内径、SF、CO和儿茶酚胺血浆浓度无明显差异.直立时各组发生改变为(1)组3出现阳性反应时间明显短于组2[(10±4)min比(17±8)min,P<0.05];(2)组3平均动脉压有即刻和持续性降低;(3)组3左室舒张末期内径降低速率明显大于其他两组;(4)SF在组3显著增强;(5)肾上腺素浓度在组3升高显著,试验终止时组1为(65±35)pg/ml,组2为(78±29)pg/ml,组3为(126±80)pg/ml(P均<0.05);去甲肾上腺素在三组均增高但组间比较差异无显著性.结论血管迷走性晕厥患者和部分正常人倾斜试验虽均呈阳性反应,但血流动力学反应和触发机制不同.前者可能与外周血管张力异常,回心血量及左室容量聚降,肾上腺素分泌增多,促使左室收缩力增强触发Bezold-Jarisch神经反射有关;而后者在发生假阳性反应时,其左室内径和SF及肾上腺素血浆浓度与阴性组无明显不同.倾斜试验时血管迷走性晕厥患者肾上腺素分泌异常在血管舒缩反应损害和左室收缩力异常方面可能起恶化作用.  相似文献   
80.

Background  

Amplification of the MYCN gene in neuroblastoma (NB) is associated with a poor prognosis. However, MYCN -amplification does not automatically result in higher expression of MYCN in children with NB. We hypothesized that the discrepancy between MYCN gene expression and prognosis in these children might be explained by the expression of either MYCN-opposite strand (MYCNOS) or the shortened MYCN-isoform (ΔMYCN) that was recently identified in fetal tissues. Both MYCNOS and ΔMYCN are potential inhibitors of MYCN either at the mRNA or at the protein level.  相似文献   
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