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81.
Increased colonic wall thickness has been reported in patients exposed to large doses of high strength pancreatic enzyme preparations who did not develop fibrosing colonopathy. This has been interpreted as evidence for a spectrum of subclinical disease. The relation between sonographically measured colonic wall thickness and pancreatic enzyme preparation and dose was studied in 86 children with cystic fibrosis (CF). Colonic wall thickness of a control group was also measured. The average thickness in all colonic regions was higher in the CF group (overall average range 0.7-2.5 mm v 0.6-1.4 mm in the control group). There was no significant relation between colonic wall thickness and age, sex, total dose of lipase, or copolymer. Apart from one patient with an early colonic stricture, none of those exposed to high doses of lipase, or the methacrylic acid copolymer Eudragit L30 D55, showed evidence of subclinical damage to the colon. The reproducibility of the sonographic measurements was poor.  相似文献   
82.
OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens.  相似文献   
83.
一氧化氮与亚硝基硫醇相互转化机制的研究   总被引:3,自引:1,他引:2  
目的:探讨一氧化氮(NO)与亚胡基硫醇间的相互转化机制。方法:应用光谱扫描、毛细管电泳和化学发光等分析技术对NO和亚砂基硫醇(R-SNO)间的相互关系进行系统研究。结果:NO在含氧实验体系极不稳定,迅速被氧化为来硝酸盐,并进而在微酸性条下与还原性巯基结合为R-SNO。R-SNO可自发而缓慢的持续释放NO,且此释放速率由于自由基的存在而加速。结论:进一步从理化性质上为内皮细胞衍生舒血管因子是亚硝基复  相似文献   
84.
85.
目的探索内镜下经扩大鼻蝶入路显露斜坡区的可行性,为切除斜坡区病变提供解剖学参考。方法在10例成人头部固定标本上,内镜下模拟扩大经鼻蝶手术入路显露斜坡区,观察有关显微解剖标志。结果扩大经鼻蝶内镜入路可磨除从鞍后到斜坡、枕骨大孔前缘的骨性结构;可显露斜坡区腹侧硬膜下的椎基底动脉及其分支、后交通动脉及其与大脑后动脉汇合处、动眼神经、脑干腹侧等结构。此入路的手术标志主要包括:蝶筛隐窝、蝶窦开口、视神经隆突、颈内动脉隆突与颈内动脉视神经隐窝、咽结节、枕骨大孔前缘。结论内镜下扩大经鼻蝶手术入路可充分显露鞍后-斜坡区的腹侧硬膜下结构,适用于此区病变的手术治疗。  相似文献   
86.
87.
过度训练机制的研究进展   总被引:1,自引:0,他引:1  
目的:了解训练适应的生理机制及过度训练与运动能力的定量关系,明确过度训练和疲劳的生理病理界限。资料来源:应用计算机检索万方数据库和中国知网1984/2006有关过度训练机制方面的文章,以"过度训练","机制","机理"等为检索词,限定文章语种为English或中文。资料选择:对资料进行初审,选取包括过度训练的分类、临床表现、诊断及过度训练产生的病理机制密切相关的文献。排除标准:重复性和内容单一文章。资料提炼:共收集50篇关于过度训练机制方面的研究文献。排除文献内容单一的文章20篇,剩余30篇纳入分析。资料综合:①过度训练的临床表现可分为两型,即交感型和副交感型。其症状、机制、运动项目及好发年龄都有所不同,但都表现为运动能力下降。交感型多发于爆发力及非耐力性项目,而副交感型则多发于耐力运动员。②过度训练的诊断主要建立在病史和典型的身体及心理症状上,并辅以生化指标、心电图、脑电图检查等。③内分泌系统兴奋和抑制之间的不平衡是造成过度训练的主要机制。目前在过度训练时免疫机能变化还不能用来解释和预测过度训练,因为这些变化与基础水平相比差别很小,临床意义不大。同步研究过度训练时的病理形态与机能变化对揭示其发病机制有着重要的意义。结论:对于训练适应的机制及训练与运动能力的定量关系的研究已取得了很大进展,但对训练产生适应和由于过度训练引起机能损害之间的界限仍很模糊。  相似文献   
88.
目的:了解新疆地区维吾尔族乳腺癌患者BRCA1基因突变及P53蛋白的表达情况。方法:选择2000-01/2004-06石河子大学医学院第一附属医院、喀什地区第一人民医院病理科收集的70例维吾尔族乳腺癌根治标本。其中维吾尔族早发性乳腺癌(≤35岁,即定为早发性乳腺癌)22例。51例患者淋巴结转移。2例为双侧乳腺癌。另选32例维吾尔族乳腺癌旁非癌组织及乳腺良性病变(纤维腺病及纤维腺瘤)作对照;上述标本为甲醛溶液固定石蜡包埋组织及少量新鲜冰冻组织。运用聚合酶链反应-单链构象多态性分析和DNA序列测定的方法检测BRCA1基因突变及用Evision二步法检测P53蛋白的表达。结果:①70例维吾尔族乳腺癌中发现9例BRCA1突变的12个新位点。②70例维吾尔族乳腺癌中BRCA1的突变率为12.86%(9/70);其中22例维吾尔族早发性乳腺癌(≤35岁)BRCA1突变率为31.82%(7/22),高于维吾尔族晚发性乳腺癌(2/48),差异有显著性(χ2=10.295,P<0.01)。③2例双侧乳腺癌中均检测出BRCA1基因的突变。④70例维吾尔族乳腺癌中发现9例BRCA1基因核苷酸多态性位点。⑤BRCA1基因突变相关性乳腺癌中P53蛋白阳性表达率高于对照组,其淋巴结转移率高于对照组,其发病年龄小于对照组。结论:BRCA1基因突变与新疆维吾尔族早发性乳腺癌及双侧乳腺癌的发生密切相关,且BRCA1突变相关性乳腺癌具有P53阳性率高、发病年龄趋于年轻化、淋巴结转移率高的趋势,这些特点有可能为基因检测前的筛选提供参考依据。  相似文献   
89.
To study red cell transfusion practice in 3216 coronary artery bypass graft (CABG) cases in 11 hospitals in 1988, abstracted patient records were stratified by diagnosis related group (DRG) (that is, DRG 106, coronary artery bypass without catheterization, or DRG 107, coronary artery bypass with catheterization) and International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) surgical procedure code. Means of units per transfused patient, age and length of stay, and in-hospital mortality rates were significantly greater for patients in DRG 106 than DRG 107. Gender was a significant factor for transfusion outcomes; female patients were more likely to undergo transfusion, and, when transfused, they received more units of red cells than male patients. For a given DRG/ICD-9-CM surgical procedure class, significant differences were found between hospitals in the percentage of patients transfused, but not in mean units of red cells per transfused patient. However, within individual hospitals, the proportion of patients transfused and the number of units per transfused patient did not vary significantly across DRG/ICD-9-CM procedure classes. These results suggest that circumstances operating within a hospital, still to be identified, had more influence on transfusion decisions than the nature of the surgical intervention.  相似文献   
90.
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