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991.
To investigate the relationship between CHEK2 mutation status and estrogen receptor (ER) status in unselected cases of early-onset breast cancer from Poland, we screened 4441 women diagnosed with breast cancer younger than 51 years and 7217 controls for three inherited mutations in CHEK2 (1100delC, IVS2+1G>A, del5395). ER status was compared between CHEK2 -positive and CHEK2 -negative breast cancer cases. A truncating mutation in CHEK2 was seen in 140 of 4441 cases and in 70 of 7217 controls [odds ratio (OR) = 3.3; 95% CI = 2.5–4.4; p < 0.0001]. ER status was available for 92 of 140 mutation carriers and for 3001 of 4301 non-carriers with breast cancer. The OR was higher for ER-positive cancers (OR = 3.9; 95% CI = 2.7–5.4; p < 0.0001) than for ER-negative cancers (OR = 2.1; 95% CI = 1.3–3.3; p = 0.002). Sixty-six of the 92 breast cancers in carriers of CHEK2 truncating mutations were ER positive compared with 1742 of the 3001 breast cancers in non-carriers (72% vs 58%; p = 0.01). Women with a CHEK2 mutation face a fourfold increase in the risk of ER-positive breast cancer and might be candidates for tamoxifen chemoprevention.  相似文献   
992.
<正>1临床资料患者,女性,16岁,高中二年级学生,特长画画。头痛不适3 d,晚餐后突然头向左侧倾斜后仰,下颌向左侧偏斜,头颈部活动及开闭口受限,颞下颌关节处持续性疼痛半小时来我院就诊。查体:神智清晰,营养中等,查体合作,心、肺、腹未见异常。专科检查:头向左侧倾斜后仰,下颌向左偏,颈部及下颌侧向运动障碍,触之左侧颈前区僵硬并有  相似文献   
993.
目的 :观察胸腺肽与干扰素联合应用与单用干扰素治疗慢性乙肝的疗效对比。方法 :选择慢性乙肝 5 8例 ,胸腺肽与干扰素联合组 32例 ,干扰素组 2 6例 ,根据用药时间观察各化验指标。结果 :血清HBeAg/抗HBe转换率至治疗第 6个月 ,联合组达 5 0 % ,干扰素组达 30 .7% ,联合组疗效显著高于干扰素组(P <0 0 5 )。两组治疗中 ,联合组HBVDNA阴转率高于干扰素组 (P <0 .0 5 )。结论 :胸腺肽与干扰素联用具有协同作用 ,治疗慢性乙肝优于干扰素组。  相似文献   
994.
Hyaluronic acid (HA) is a naturally occurring polyanionic, polysaccharide that consists of N-acetyl-D-glucosamine and beta-glucoronic acid. It is present in the intercellular matrix of most vertebrate connective tissues especially skin where it has a protective, structure stabilizing and shock-absorbing role. The unique viscoelastic nature of HA along with its biocompatibility and non-immunogenicity has led to its use in a number of clinical applications, which include: the supplementation of joint fluid in arthritis; as a surgical aid in eye surgery; and to facilitate the healing and regeneration of surgical wounds. More recently, HA has been investigated as a drug delivery agent for various routes of administration, including ophthalmic, nasal, pulmonary, parenteral and topical. In fact, regulatory approval in the USA, Canada and Europe was granted recently for 3% diclofenac in 2.5% HA gel, Solaraze, for the topical treatment of actinic keratoses, which is the third most common skin complaint in the USA. The gel is well tolerated, safe and efficacious and provides an attractive, cost-effective alternative to cryoablation, curettage or dermabrasion, or treatment with 5-fluorouracil. The purpose of this review is to describe briefly the physical, chemical and biological properties of HA together with some details of its medical and pharmaceutical uses with emphasis on this more recent topical application.  相似文献   
995.
Chronic encapsulated mediastinal abscess is an unusual complication of previous open heart surgery. We report on the case of a 79 year old male who presented with epigastric fistulization of an encapsulated anterior mediastinal abscess 12 years after a redo aortic valve replacement for prosthetic valve endocarditis. The encapsulated abscess and its complex branching tracts and the cutaneous fistula were excised completely except the thin longitudinal strip of the ascending aorta which formed part of the posterior wall of the infected tract. This was covered with transposed greater omentum based on right gastroepiploic artery pedicle. Patient remains fit and well 2 years after his operation.  相似文献   
996.
997.
人原始生殖细胞分离培养的初步研究   总被引:3,自引:0,他引:3  
[目的]探讨分离培养人原始生殖细胞的最佳条件。[方法]用胰蛋白酶消化5~9周人流组织中的人胚生殖嵴,获取人原始生殖细胞。以小鼠胚胎成纤维细胞作饲养层,在高糖DMEM培养基中添加10μmol/L福司克林(forskolin)和5~μg/L碱性成纤维细胞生长因子(bFGF)的培养液中培养、传代,并对子代细胞进行碱性磷酸酶活性检测和体外分化实验。[结果]原代培养时形成许多大小不等,形态各异的由人原始生殖细胞组成的集落,约5~7d传代。传代后,集落生长,变大。细胞培养到第七代,检测碱性磷酸酶染色为强阳性,体外分化实验有拟胚体形成。[结论]人原始生殖细胞可以用胰蛋白酶消化分离培养。用高糖DMEM培养基,添加forskolin和bFGF有利于人原始生殖细胞增殖。体外分化实验初步证实人原始生殖细胞具有多向分化潜能。  相似文献   
998.
SUMMARY The incidence of climacteric symptoms was determined in 247 healthy premenopausal women in a community setting. These volunteers had been recruited to a longitudinal study of bone density. Of these subjects, 46 ceased to menstruate during the study, and in this subgroup symptoms were compared before and after cessation of menstruation. Only hot flushes increased after cessation of menstruation in the longitudinal study and showed age correlation in the cross-sectional study. Hot flushes thus emerged as a true menopausal symptom. Although evidence for this is weaker, cold sweats and suffocation seem likely to be genuinely menopausal. Breast discomfort and the four mood symptoms of irritability, excitability, depression and poor concentration improved after cessation of menstruation, and this study gives no support for their being part of the menopausal syndrome; it suggests that these symptoms are more likely to be related to menstruation than to the menopause.  相似文献   
999.
目的对电动牙刷和手动牙刷在去除菌斑、维护牙龈健康、对色素和牙结石的作用、可靠性、不良作用和成本等进行比较.方法计算机检索Cochrane口腔健康协作组临床试验资料库(截至2004年6月17日)、Cochran临床对照试验中心资料库(Cochrane图书馆2004第2期)、MEDLINE(1966~2004)、EMBASE(1980~2004第2周)和CINAHL(1982~2004第2周),并与制造商联系以获取更多资料.根据下列标准纳入随机对照试验:随机分配研究对象;参加者为手运动无障碍的普通人群;干预措施为无监督的手动或电动牙刷刷牙,至少4周;主要结局指标为试验期间菌斑和牙龈炎的变化.由6个作者独立评价并纳入研究资料.用随机效应模型进行Meta分析,用标准化均数差(SMD)及其95%CI测量效果.检查可能的异质性来源,并针对研究质量和发表偏倚进行敏感性分析.为便于讨论,将SMD转换为百分率.结果对包含3 855例研究对象的42个试验进行系统评价,结果显示,旋转振动型电动牙刷去除菌斑和减低牙龈炎的效果在短期内明显优于手动牙刷,并在3个月以上的研究中显示降低了牙龈炎指数.在1~3个月的研究中,菌斑SMD为-0.43 [95%CI (-0.72, 0.14)],牙龈炎SMD为-0.62 [95%CI (-0.90, 0.34)],Quigley Hein菌斑指数降低11%,Loe and Silness龈炎指数降低6%.在3个月以上的研究中,菌斑指数SMD为-1.29 [95%CI (-2.67, 0.08)], 龈炎指数为-0.51 [95%CI (-1.76, 0.25)],Ainamo Bay探诊出血指数降低17%.短期研究之间有异质性,敏感性分析显示当选择高质量的研究时结果是肯定的,没有证据表明有发表偏倚.采取其他设计的电动牙刷并不比手动牙刷更优.对成本、可靠性和不良作用的报道不一致,已报道的不良作用都是局限的、暂时的.结论旋转振动型电动牙刷去除牙菌斑、减少牙龈炎的效果优于手动牙刷.遵守方法学指南和更标准化的设计有益于将来的研究和Meta分析.  相似文献   
1000.
BACKGROUND: Transfusion-related acute lung injury (TRALI) is clinically similar to the adult respiratory distress syndrome (ARDS) and has been linked to the transfusion of leukocyte antibodies in blood components. Animal model have implicated neutrophil (PMN)-priming agents in ARDS; however, two agents were required. Previous studies showed the generation of PMN-priming agents during blood storage. Thus the association of PMN-priming agents with TRALI was examined. STUDY DESIGN AND METHODS: Ten patients with TRALI and 10 with febrile or urticarial reactions (control group) were evaluated. The presence of PMN-priming activity was tested in the patients' pretransfusion and posttransfusion blood samples by incubating PMNs with these samples followed by activation of the respiratory burst. Plasma lipids were separated by normal-phase high-performance liquid chromatography (HPLC), and the priming activity was evaluated. The presence of leukocyte antibodies was determined in the blood donors and patients with TRALI. RESULTS: Significantly more PMN-priming activity was present in the posttransfusion sera (11.4 +/? 1.8 nmol superoxide anion/min, mean +/? SEM; n=10) and plasma of patients with TRALI than in their pretransfusion sera (6.5 +/? 1.5: n=10) or in the pretransfusion and posttransfusion sera (5.1 +/? 1.3, n=10; and 4.5 +/? 1.4, n=10, respectively) and from the controls (p < 0.05). HPLC separation of lipids demonstrated that three active species were present in the posttransfusion plasma samples of TRALI patients. All the patients with TRALI had underlying clinical factors, such as infection, cytokine administration, recent surgery, or massive transfusion, while only 2 of 10 control patients had these clinical conditions. None of the donors had significant titers of HLA or HLA-DR antibodies; however, 50 percent had weak positivity for granulocyte antibodies. CONCLUSION: TRALI is the result of two clinical events, the first being a predisposing clinical condition and the second being the transfusion of biologically active lipids in stored blood.  相似文献   
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