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971.
Ninety-two hospitals in a three-state mid-Atlantic region were surveyed to determine their policy toward obtaining written informed consent for transfusion and to examine the content of written consent documents and the process by which consent is obtained. Of 81 hospitals responding, 50 (62%) required written informed consent. Hospitals with fewer than 200 beds were more likely to require written informed consent. The attending physicians had responsibility for obtaining consent in 28 (57%) of 49 institutions, most often on the day or evening before surgery. Twenty-seven of 48 forms mentioned complications: hepatitis in 80 percent, human immunodeficiency virus infection in 46 percent, nonhemolytic reactions in 32 percent, and hemolysis in 25 percent. Alternatives to allogeneic transfusion were mentioned infrequently; eight hospital forms listed autologous transfusion options and only two mentioned designated donation. The reading level required to comprehend 34 consent forms submitted was grade 14.6, which has been attained by only 23 percent of the adult United States population. Although the majority of respondent institutions require written informed consent, those forms, per se, do not document that the fundamental tenets of informed choice have been applied to the decision to transfuse blood.  相似文献   
972.
目的:观察内皮前体细胞自体移植后能否促进血管新生、改善心肌灌注、进而改善心脏功能。方法:实验于2004-01/05在解放军总医院心内科实验室完成。①实验分组:雄性新西兰白兔32只,体质量3.0~3.5kg,随机分为治疗组和对照组,每组16只。②实验方法:治疗组自骨髓获取内皮前体细胞培养扩增。结扎动物冠状动脉前降支根部。心电图检测至少5个胸前导联出现ST段显著抬高作为模型制作成功标志。2.5g/L胰蛋白酶消化细胞,洗涤干净后5mL磷酸盐缓冲液悬浮细胞,结扎前降支2h后将细胞悬液从耳静脉注入动物体内,移植细胞数量为(9.8±2.9)×106个/只。对照组注射磷酸盐缓冲液5mL。饲养5周。③实验评估:分别行超声心动图检查和左心室压力曲线检测心脏功能和心肌组织的梗死情况以及通过免疫组织化学检测观察血管密度。结果:纳入新西兰白兔共32只,因前降支细小排除2只。对照组因心功能衰竭和腹泻各死亡1只。治疗组结扎前降支后突发室性心律失常死亡1只。最终27只进入实验。①体外培养的内皮前体细胞生长迅速,能够在2~3周达到预定移植细胞数量。②内皮前体细胞移植5周后,超声心动图检测显示治疗组动物心肌功能指数显著降低(P<0.01),左心室射血分数显著高于对照组(P<0.01),左心室舒张末压明显低于对照组(P<0.05),而等容收缩期左室压力最大上升速率显著升高(P<0.05)。③治疗组心肌梗死面积显著减小(P<0.01),而血管密度明显高于对照组(P<0.01)。④标记细胞主要位于梗死心肌组织,大部分整合至毛细血管中,参与血管新生。结论:内皮前体细胞自体移植能促进缺血心肌血管新生,有效改善缺血心肌的灌注,进而改善心脏功能。  相似文献   
973.
974.
Management of malignant neoplasms of the sinonasal tract and skull base is hampered by the relative low incidence and pathologic diversity of patient presentations. Many studies have reported successful outcomes in the endoscopic management of malignancy since 1996, and these are summarized in this article. Nonsurgical adjuvant therapies are important for locoregional control because surgery occurs in a restricted anatomic space with close margins to critical structures, and distant disease is an ongoing concern in these disorders. There remains a need for collaborative consistent multicenter reporting, and international registries have been established to assist in such efforts.  相似文献   
975.
Aim: To determine whether the size and shape of the placental surface predict blood pressure in childhood. Methods: We studied blood pressure in 471 nine‐year‐old Indian children whose placental length, breadth and weight were measured in a prospective birth cohort study. Results: In the daughters of short mothers (相似文献   
976.

Background

Studies have shown that the shape and size of the placenta at birth predict blood pressure in later life. The influences that determine placental morphology are largely unknown. We have examined the role of mother’s body size.

Methods

We studied 522 neonates who were born in a maternity hospital in Mysore, South India. The weight of the placenta and the length and breadth of its surface, were measured after delivery.

Results

Higher maternal fat mass predicted a larger placental surface (p = 0.02), while larger maternal head circumference predicted a more oval placental surface (p = 0.03). Higher maternal fat mass and larger maternal head circumference were associated with greater placental efficiency, indicated by lower ratios of the length (p = 0.0003 and p = 0.0001 respectively) and breadth (p = 0.0002 and p < 0.0001) of the surface to birthweight. In a sub-sample of 51 mothers whose own birthweight was available, higher maternal birthweight was related to lower ratios of the length and breadth of the surface to birthweight (p = 0.01 and 0.002). Maternal height was unrelated to placental size or shape.

Conclusions

Higher maternal fat mass, reflecting the mother’s current nutritional state, and larger maternal head circumference, reflecting the mother’s fetal/infant growth, are associated with changes in the shape and size of the placental surface and greater placental efficiency. We suggest that these associations reflect effects of the mother’s nutrition at different stages of her lifecourse on the development of the placenta and on materno-placento-fetal transfer of nutrients.  相似文献   
977.
OBJECTIVE: To report on the occurrence of methylenetetrahydrofolate reductase (MTHFR) deficiency in patients with retinal vein occlusion (RVO). DESIGN: Prospective case series PARTICIPANTS: Fifty-nine consecutive patients with newly diagnosed RVO seen at the Retina Unit in the Tel Aviv Medical Center during 1997. METHODS/TESTING: Interviews and multiple blood analyses were done. Data were compared to the reported incidence of MTHFR deficiency in the Israeli population at large. RESULTS: Twenty-six patients (44.1%) were heterozygotes and 11 (18.6%) were homozygotes for 677C-T mutation in MTHFR. The MTHFR 677C-T homozygosity was documented as being present in 10.4% of healthy individuals in the Israeli population. The difference in homozygosity was found to be statistically significant (P = 0.038). CONCLUSIONS: Retinal vein occlusion may be associated with a mutation in MTHFR.  相似文献   
978.
Fish-eye disease is a familial syndrome with corneal opacification, major high density lipoprotein (HDL) deficiency in plasma, significant cholesterol esterification in plasma on non-HDL lipoproteins, generally without premature coronary disease. This first British male case from unrelated British parents had infarcts when aged 49 and 73 years but was asymptomatic at age 81 years, with plasma cholesterol 4.3-7.1 mmol/litre, triglycerides 1.8-2.2 mmol/litre, HDL cholesterol < 0.1 mmol/litre, apolipoprotein A-I < 0.16 g/litre, lipoprotein(a) 0.61 g/litre. Cholesterol esterification was impaired using HDL-3 and A-I proteoliposomes but not using VLDL/IDL/LDL. The findings are those of LCAT deficiency with the classic fish-eye disease defect. Most of the 22 reported cases were homozygous or heterozygous for a Thr-Ile mutation at codon 123 of the lecithin:cholesterol acyltransferase (LCAT) gene. This patient was a double heterozygote for this mutation and a second new incompletely defined mutation affecting LCAT expression as defined by reduced mass and activity in plasma.  相似文献   
979.
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