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91.
脊柱侧弯患者呼吸功能减退的病因学至今尚无定论。力学因素很可能是呼吸功能减退的原因之一。通过比较脊柱则弯患者与下沉人深呼吸时胸段脊柱及胸廓三维运动来探讨力学因素对呼吸功能减退的影响。脊柱侧弯患者胸廓及脊柱骨架的僵直有可是影响呼吸动力学的原因之一。  相似文献   
92.
93.
The current emphasis on cost containment and its impact on pharmacy practice is reviewed. Methods by which existing standards of practice can be maintained are presented. Strategies for increasing the pharmacist's role in patient care within this climate are discussed. Examples of cost-effective approaches to pharmacy management and practice are outlined. Specific approaches include fiscal management of inventory, efficient use of personnel, and developing programs that reduce health-care cost.  相似文献   
94.
Woodruff  WW  d; Merten  DF; Wagner  ML; Kirks  DR 《Radiology》1986,159(2):511-514
Chronic pulmonary embolism with pulmonary hypertension in children is rarely diagnosed clinically; literature review yielded only 17 recorded cases. To demonstrate the radiographic features as well as to encourage the diagnostic consideration of chronic pulmonary embolism in children, this report focuses on three additional children with chronic pulmonary embolism. Of these 20 total cases, only two were not catheter-related; 17 patients had emboli as a complication of ventriculoatrial shunting, and one had emboli secondary to indwelling venous hyperalimentation. Analysis of the information available on the 20 cases revealed the following radiographic features: cardiomegaly (19 cases), large central pulmonary arteries with rapid distal tapering (15 cases), oligemia (five cases), "infiltrate" (three cases), and effusion (two cases). With increasing use of central catheterization as treatment for children with chronic illness, the incidence of chronic pulmonary embolism will likely increase; therefore, clinical diagnosis should reflect this increase. The radiologist in particular should be aware of the clinical and radiologic features of chronic pulmonary embolism in children.  相似文献   
95.
灰毡毛忍冬化学成分研究V灰毡毛忍冬素F和G的结构测定   总被引:5,自引:0,他引:5  
Lonicera macranthoides Hand. -Mazz of Caprifoliaceae is the sources of Jinyinhua, which is a well known antipyretic and antidote in traditional Chinese medicine. Chemical studies led us to isolate 11 new compounds.Further purification of a bioactive fraction from the EtOAc soluble portion yielded two new compounds named macranthoin F and G,Their structures wereelucidated as methyl 3,4-O-dicaffeoylquinate(Ⅰ)and methyl 3,5-O-dicaffeoylquinate(Ⅱ).  相似文献   
96.
脊柱侧弯板棍系统的体外生物力学测试   总被引:4,自引:0,他引:4  
目的 测试脊柱侧弯板棍系统 (PRSS)内固定后脊柱标本的刚度及其钉钩的拔出力 ,并根据与完整脊柱刚度的比较来评估根据该内固定系统临床应用的可靠性。方法 选择 12节段猪脊柱标本 12具 ,测定其前屈、后伸、侧屈及旋转时的刚度 ;再切除前方的椎间盘和后方的小关节使脊柱失稳 ,重复各向运动刚度测试 ;然后使用PRSS在失稳脊柱标本上进行内固定 ,再重复各向运动刚度测试。通过自身对照比较了解PRSS内固定后脊柱的刚度 ;选择单节段猪胸椎标本 6个及腰椎标本 7个 ,分别拧入PRSS钉钩后进行拔出力测试。结果 在猪脊柱标本前屈、后伸、旋转及侧屈活动的刚度测试中 ,与完整脊柱的刚度相比 ,失稳脊柱各向运动的刚度均明显减小 (P <0 .0 5 ) ,而PRSS内固定后脊柱各向运动的刚度均明显高于完整脊柱 (P <0 .0 5 )。在猪脊椎标本上 ,PRSS胸椎钉钩的拔出力为 (5 46 .0 4± 142 .94)N ,腰椎钉钩的拔出力为 (90 8.5 0± 2 13.0 9)N ,胸椎钉钩的拔出力明显小于腰椎钉钩的拔出力 (P <0 .0 5 )。结论 PRSS内固定术后脊柱的刚度高于完整脊柱 ,其钉钩可提供一定的提拉力。  相似文献   
97.

Background

Some young women experience delays in diagnosis of cervical cancer, but little research about ways of studying these delays has been published. A major challenge is that gynaecological symptoms are common in young women, but cervical cancer is rare. This study describes the development and testing of a measure for studying delays in diagnosis in young women with cervical cancer.

Methods

Prospective development of an interview measure and testing of its ability to reliably and systematically collect relevant data in two large hospitals in London, UK using 27 women aged 18–40 diagnosed with cervical cancer in the previous two years. We developed a semi-structured interview schedule and data extraction form to systematically collect data on symptoms (including nature and duration) and risk factors for delayed diagnosis from young women with cervical cancer. We piloted the measure among young women with cervical cancer (audiorecording it with their permission), refining it iteratively. To complete the measure, we developed a database for managing the data and a manual for using the schedule. Two researchers extracted data from the recorded interviews to assess inter-rater reliability.

Results

The final interview schedule yielded quantitative data on the nature and duration of symptoms and risk factors for delayed diagnosis. Inter-rater reliability was high. In the pilot, 12 of the 27 women were diagnosed via symptomatic presentation. Median time from the symptom triggering presentation to presentation was one month (interquartile range 0–4 months). Median time from presentation to diagnosis was three months (interquartile range 1–8.5 months).

Conclusions

We have developed a reliable tool for measuring the nature and duration of symptoms in young women with cervical cancer. Pilot data suggest that a substantial proportion of women experience delay between first presentation and diagnosis.
  相似文献   
98.
学术背景:骨髓基质细胞能够表达多种细胞表面分子及分泌多种细胞生长因子,其共同组成的微环境可以调节造血干细胞的分化和发育。造血干细胞和神经干细胞可表达很多共同基因.提示二者存在类似的发育和分化机制。 目的:深入认识骨髓基质细胞提供的微环境对神经干细胞的诱导分化作用。 检索策略:由该论文的研究人员应用计算机检索Pubmed数据库1992—01/2007—03的相关文献,检索词“bone marrow stem cells,microenvironment,neuml stem cells,differentiation”,并限定文章语言种类为English。同时计算机检索CHKD期刊全文数据库1994—01/2006—12的相关文献,检索词“骨髓基质细胞,神经干细胞,分化”,并限定文章语言种类为中文。共检索到125篇文献,对资料进行初审,纳入标准:①文章所述内容应与骨髓基质细胞密切相关。②同一领域选择近期发表或在权威杂志上发表的文章。排除标准:①重复性研究。②Meta分析。 文献评价:文献来源主要是通过对骨髓基质细胞所提供的微环境诱导神经干细胞分化方面的内容进行汇总分析。所选用的31篇文献中,7篇为综述,其余均为临床或基础实验研究。 资料综合:①骨髓基质细胞易于分离培养,其分泌的各种细胞因子、生长因子和细胞外基质成分所构成的微环境能够调节神经干细胞的发育和分化。②从mRNA水平看,骨髓基质细胞不仅有脑源性神经生长因子和神经生长因子的表达,还有胶质细胞源性神经营养因子的表达。从蛋白水平看,采用ELISA法在骨髓基质细胞的培养液和细胞蛋白中均可检测到胶质细胞源性神经营养因子。在生理状态下,骨髓基质细胞能分泌具有神经营养活性的物质,对损伤的运动神经元具有保护作用。此外研究证实骨髓基质细胞分泌至细胞外的可溶性物质具有直接调节神经干细胞分化的能力。 结论:骨髓基质细胞通过分泌各种细胞因子所构成的微环境能够调节神经干细胞的发育,并诱导其向神经元方向分化。神经干细胞增殖分化的调控是非常复杂的过程,各因子间可能存在协同或拮抗作用,具体作用机制以及细胞信号转导通路还需深入研究。  相似文献   
99.
100.
High-dose chemotherapy with or without radiotherapy followed by autologous transplantation of hematopoietic progenitor cells is an effective treatment for patients with high-risk or relapsed non- Hodgkin's lymphoma. Chemotherapy and/or hematopoietic growth factors have been used to mobilize progenitor cells in the peripheral blood for transplantation. However, the mobilized blood cell products have been found to be frequently contaminated with tumor cells, and techniques have not been developed to purge tumor cells from these products. In addition, the minimum number of hematopoietic progenitor cells required for engraftment has not yet been fully elucidated. We treated 21 patients with a single infusion of cyclophosphamide (4 g/m2) followed by daily administration of granulocyte colony-stimulating factor (G- CSF). After recovery of the white blood cell count, a single 3-hour apheresis collection was performed. The apheresis product was then applied to a discontinuous Percoll gradient. The low-density fractions resulting from this separation procedure were enriched for CD34+ progenitor cells (total cell yield, 19.5%; CD34+ cell recovery, 81.2%). These enriched cellular products were treated with a panel of anti-B cell or anti-T cell monoclonal antibodies and complement in an effort to remove residual tumor cells. After treatment of the patient with myeloablative therapies, the enriched and purged cells were reinfused. Hematologic recovery was rapid, with median neutrophil engraftment in 10 days [absolute neutrophil count (ANC), greater than 0.5 x 10(9)/L] and 11 days (ANC, greater than 1.0 x 10(9)/L). Median platelet transfusion independence required 13 days. The rapidity of multilineage engraftment correlated with the number of CD34+ cells per kilogram that were infused. Patients who received more than 2 x 10(6) CD34+ cells per kilogram had rapid hematologic engraftment, whereas those patients transplanted with less than 2 x 10(6) CD34+ cells per kilogram had slower platelet recovery. Modeling studies using a lymphoma cell line with a t(14; 18) chromosomal translocation demonstrated the successful removal of tumor cells assayed using the polymerase chain reaction (PCR) after the processing and purging. Four of the 21 patients had PCR- detectable lymphoma cells in the bone marrow and peripheral blood; however, the enriched and purged blood products reinfused in all four did not contain detectable tumor cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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