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51.

Background  

Many quality and safety improvement methods in healthcare rely on a complete and accurate map of the process. Process mapping in healthcare is often achieved using a sequential flow diagram, but there is little guidance available in the literature about the most effective type of process map to use. Moreover there is evidence that the organisation of information in an external representation affects reasoning and decision making. This exploratory study examined whether the type of process map - sequential or hierarchical - affects healthcare practitioners' judgments.  相似文献   
52.
目的:通过对图书馆员的人格因素和职业现状分析,为图书馆的人力资源管理提供参数。方法:于2005-06/08纳入大连理工大学伯川图书馆馆员72人作为人格测试组,男7人,女65人;同时纳入2005-07前在职的全部馆员122人作为职业现状分析组,男26人,女96人。采用国际公认的卡特尔16种人格因素问卷,对人格测试组进行人格测试。问卷从16个相对独立的人格维度对人进行描绘,全套测试题共187题,每题设有a,b,c3种可供选择的答案。将测试结果输入心理测试软件系统,给出粗分和标准分,再运用软件进行数据的统计分析。对职业现状分析组的全体馆员进行了性别,年龄结构,男女馆员在各工作部门的分布,及馆员的学历构成,技术职称和领导职务的担任比例统计分析。观察人格测试组卡特尔16种人格因素问卷人格类型的次元因素和综合个性应用评价分数,并对全体馆员的自然状况列表进行统计分析,分析其职业现状。结果:发放卡特尔16种人格因素问卷72份,回收完整问卷46份,回收率63.9%,有效率100%。最终人格测试组46人进入结果分析,男5人,女41人。职业现状分析组122人,全部进入结果分析。①人格测试组聪慧性、幻想性、自律性均高于全国专业技术人员常模,差异有显著性意义(9.74±1.22;8.88±1.22;13.11±2.36,11.83±1.25;13.89±2.59,12.40±1.47;t=4.780,3.676,3.901,2.783,P<0.001~0.01)。被试馆员怀疑性和紧张性低于全国专业技术人员常模,差异有显著性意义(9.39±2.85,10.56±1.57;9.76±3.72,11.19±1.65;t=-2.783,-2.606,P<0.01,0.05)。②女性图书馆员占总人数的78.7%,男性图书馆员在年龄结构上处于年龄段的两端,在生理上处于成年早期(30.7%)和晚期(38.4%);女性馆员的年龄集中于30~50岁的年龄段(86.3%)。③男馆员在综合办公室、自动化部和技术服务部的人数分布方面占据优势地位(38.4%,11.5%,11.5%);而女性馆员集中于期刊咨询部、文献建设部、流通阅览部和回溯建库等信息服务咨询部门(24%,15.6%,40.6%,4.2%)。④男馆员在获得博士、双学士、学士学位,及本科、中专学历方面的人数比例大于女性馆员,而女性馆员在获得硕士学位及大专和较低学历方面所占的比例大于男性馆员。⑤男性馆员在高级技术职称和馆级领导高端决策层占优势,在初级和较低技术职称中占比例较大;女性馆员在中级技术职称中级领导层上占比例大于男性馆员。结论:图书馆员女性化,而男性馆员在知识结构、职称、高端决策层领导职务的担任和承担高技术性工作方面的整体水平优于女性馆员。更应着重分析女性图书馆员的生理、心理特点,人格因素和职业特征,进行人力资源的优化组合。  相似文献   
53.
成人骨髓间充质干细胞的体外培养及生物学特性   总被引:3,自引:4,他引:3  
目的:观察成人骨髓间充质干细胞体外分离培养方法及其生物学特性,为骨髓间充质干细胞的临床应用奠定技术基础。方法:实验于2005-12在吉林省四平市中心医院中心实验室进行。实验材料:人骨髓间充质干细胞,Ficoll淋巴细胞分离液,胎牛血清,牛血清白蛋白,α-MEM培养基,胰蛋白酶,FITC标记的CD44和CD90。实验方法:①人骨髓间充质干细胞的分离与培养:采集成人骨髓,密度梯度法分离单个核细胞,条件培养基培养和扩增,倒置光学显微镜下观察细胞形态及生长情况。②人骨髓间充质干细胞生长曲线的测定:取生长良好的P1,P5,P10细胞,用胰酶消化,接种于24孔板培养,每天各取3孔消化计数细胞,取平均值,连续培养7d,绘制生长曲线。③人骨髓间充质干细胞表面标志的测定:取生长良好P5细胞进行免疫荧光染色鉴定(CD44,CD90并设同型对照)。④人骨髓间充质干细胞的冻存及复苏:收集生长良好细胞,计数细胞密度及冻前存活率。将细胞加入到细胞冻存液中液氮冷冻保存。30d后复苏细胞,每日倒置光学显微镜下观察细胞生长状况。结果:①倒置显微镜下观察细胞形态:倒置显微镜下观察细胞呈纤维形,漩涡状生长。②人骨髓间充质干细胞的生长曲线分析:传代的细胞生长较原代要快,从第10代开始细胞生长开始出现缓慢征象。③细胞表面标记检测结果:免疫荧光染色后细胞膜着色明显,CD44,CD90阳性率均大于90%。④细胞冻存及复苏生长特性分析:椎虫蓝计数细胞存活率90%以上,增殖能力强,和未冻存过的传代细胞具有同样的生长特性。结论:应用密度梯度法分离法能获得较高纯度的骨髓间充质干细胞,能在体外长期培养,在传代培养5代内生长旺盛且生物学特性稳定。  相似文献   
54.
A chromosomal breakage syndrome with profound immunodeficiency   总被引:5,自引:0,他引:5  
Conley  ME; Spinner  NB; Emanuel  BS; Nowell  PC; Nichols  WW 《Blood》1986,67(5):1251-1256
The chromosomal breakage syndromes--ataxia-telangiectasia, Fanconi's anemia, and Bloom's syndrome--are associated with growth failure, neurologic abnormalities, immunodeficiency, and an increased incidence of malignancy. The relationship between these features is unknown. We recently evaluated a 21-year-old female with more severe chromosomal breakage, immunodeficiency, and growth failure than in any of the mentioned disorders. As of November 1985, the patient remains clinically free of malignancy. At age 18, the patient's weight was 22.6 kg (50th percentile for seven years), height was 129 cm (50th percentile for eight years), and head circumference was 42 cm (50th percentile for six months). Laboratory studies demonstrated a marked decrease in both B and T cell number and function. The peripheral blood contained 400 to 900 lymphocytes/microL with 32% T11 cells, 17% T4 cells, and 21% T8 cells. The proliferative responses to phytohemagglutinin (PHA), pokeweed mitogen, and concanavalin A were less than 10% of control. There were 1% surface IgM positive cells, and serum IgG was 185 mg/dL, IgM 7 mg/dL, IgA 5 mg/dL. In lymphocyte cultures stimulated with the T cell mitogens PHA, phorbol ester, and interleukin 2, 55% of the banded metaphases demonstrated breaks or rearrangements. The majority of the breaks involved four fragile sites on chromosomes 7 and 14, 7p13, 7q35, 14q11, and 14q32. These are the sites of the genes for the T cell-antigen receptor and the immunoglobulin heavy chain and are sites of gene rearrangement in lymphocyte differentiation. Epstein-Barr virus stimulated B cells and fibroblast cultures also demonstrated a high incidence of breaks, but the sites were less selective. These findings suggest that the sites of chromosomal fragility in the chromosomal breakage syndromes may be informative and that factors other than the severity of the immunodeficiency or the high incidence of chromosomal damage may contribute to the occurrence of malignancy in the chromosomal breakage syndromes.  相似文献   
55.
The favorable cellular response of newly developed cell line, buffalo embryonic stem (ES) cells to three-dimensional biodegradable chitosan–gelatin composite scaffolds with regard to stem-cell-based tissue engineering is described. Chitosan–gelatin composites were characterized by a highly porous structure with interconnected pores, and the mechanical properties were significantly enhanced. Furthermore, X-ray diffraction study indicated increased amorphous content in the scaffold on the addition of gelatin to chitosan. To develop a transfectant of green fluorescence protein (GFP)–buffalo ES cell, transfection of GFP plasmid to the cell was carried out via the electroporation procedure. In comparison with pure chitosan, cell spreading and proliferation were greater in highly visualized GFP-expressing cell–chitosan–gelatin scaffold constructs. The relative comparison of biological response involving cell proliferation and viability on the scaffolds suggests that blending of gelatin in chitosan improved cellular efficiency. Studies involving scanning electron and fluorescence microscopy, histological observations and flow cytometer analysis of the constructs implied that the polygonal cells attached to and penetrated the pores, and proliferated well, while maintaining their pluripotency during the culture period for 28 days. Chitosan–gelatin scaffolds were cytocompatible with respect to buffalo ES cells. The study underscores for the first time that chitosan–gelatin scaffolds are promising candidates for ES-cell-based tissue engineering.  相似文献   
56.

Background

Cardiovascular magnetic resonance (CMR) has excellent capabilities to assess ventricular systolic function. Current clinical scenarios warrant routine evaluation of ventricular diastolic function for complete evaluation, especially in congestive heart failure patients. To our knowledge, no systematic assessment of diastolic function over a range of lusitropy has been performed using CMR.

Methods and Results

Left ventricular diastolic function was assessed in 31 subjects (10 controls) who underwent CMR and compared with Transthoracic echocardiogram (TTE) evaluation of mitral valve (MV) and pulmonary vein (PV) blood flow. Blood flow in the MV and PV were successfully imaged by CMR for all cases (31/31,100%) while TTE evaluated flow in all MV (31/31,100%) but only 21/31 PV (68%) cases. Velocities of MV flow (E and A) measured by CMR correlated well with TTE (r = 0.81, p < 0.001), but demonstrated a systematic underestimation by CMR compared to TTE (slope = 0.77). Bland-Altman analysis of the E:A ratio and deceleration time (DT) calculated from each modality showed excellent agreement (bias -0.29, and -10.3 ms for E:A and DT, respectively). When assessing morphology using TTE, CMR correctly identified patients as having normal or abnormal inflow conditions.

Conclusion

We have shown that there is homology between CMR and TTE for the assessment of diastolic inflow over a wide range of conditions, including normal, impaired relaxation and restrictive. There is excellent agreement of quantitative velocity measurements between CMR and TTE. Diastolic blood flow assessment by CMR can be performed in a single scan, with times ranging from 20 sec to 3 min, and we show that there is good indication for applying CMR to assess diastolic conditions, either as an adjunctive test when evaluating systolic function, or even as a primary test when TTE data cannot be obtained.  相似文献   
57.
58.
目的:建立能反应自身免疫特点的类风湿性关节炎动物模型,为进一步研究该病发病机制奠定基础。方法:实验于2006-03/12在南方医科大学实验动物中心完成。①实验材料:SPF级2~4个月龄NOD.scid小鼠20只,体质量17~22g,雌雄各半;人类风湿性关节炎滑膜组织(佛山市第一人民医院风湿科提供,患者知情同意);骨关节炎滑膜及正常软骨(南方医院创伤骨科提供,患者及供者知情同意)。②实验分组:将小鼠随机分为2组,类风湿性关节炎滑膜组和骨关节炎滑膜组,雌雄不限,每组10只。③实验过程:每组小鼠背部皮下植入的正常软骨组织,随后将类风湿性关节炎滑膜和骨关节炎滑膜植入软骨之上。④造模10周后麻醉下处死小鼠,用放射免疫法检测血清中肿瘤坏死因子α含量,移植物进行组织病理学观察,并进行组织学积分。结果:①模型鼠一般情况:实验期间NOD.scid小鼠无手摸皮骨感、活动度差、毛稀疏等典型移植物抗宿主疾病表现,模型鼠在SPF环境下10周存活率100%。②肿瘤坏死因子α含量:类风湿性关节炎滑膜组鼠血清中肿瘤坏死因子α放射含量类风湿性关节炎组明显高于骨关节炎组[(0.80±0.06),(0.70±0.03)μg/L,t=4.466,P<0.001]。③组织病理学观察:苏木精-伊红染色,骨关节炎滑膜组只见少量的滑膜细胞增生和炎症细胞,移植的滑膜组织主要被纤维组织形成的条索状物代替,无明显地软骨被侵蚀破坏发生;类风湿性关节炎滑膜组可明显见到大量的滑膜细胞增生和生化中心形成,病变部位的组织结构间质变为疏松,变为境界不清晰的颗粒状或块状无结构强嗜酸性红染物质;软骨边缘被滑膜组织侵蚀破坏明显;类风湿性关节炎滑膜组滑膜增生、软骨侵蚀和软骨降解积分均高于骨关节炎滑膜组(P<0.04)。结论:在NOD.scid体内可成功建立类风湿性关节炎动物模型。  相似文献   
59.
Undifferentiated (embryonal) sarcoma (UES) is an uncommon malignant mesenchymal hepatic tumor that occurs in older children and young adults. Fourteen cases are correlated with radiologic and pathologic findings. Radiologic findings reflect the spectrum of solid to cystic appearances observed in the gross specimens. Sonography typically demonstrates a large mass that may be predominantly solid with many small anechoic spaces or may be cystic. Computed tomography reveals a hypodense mass with hyperdense septa of variable thickness and a dense peripheral rim corresponding to the fibrous pseudocapsule of the tumor. Angiographically, UES is usually hypovascular with tumoral vessels, although hypervascular and avascular patterns occur. Prognosis of UES is poor, with a median survival of less than 1 year. Radiologists should be familiar with this malignant tumor since it may present as a large cystic hepatic mass, suggestive of a benign lesion.  相似文献   
60.
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