全文获取类型
收费全文 | 373984篇 |
免费 | 34470篇 |
国内免费 | 25002篇 |
专业分类
耳鼻咽喉 | 3303篇 |
儿科学 | 3829篇 |
妇产科学 | 5136篇 |
基础医学 | 44637篇 |
口腔科学 | 6491篇 |
临床医学 | 50723篇 |
内科学 | 54761篇 |
皮肤病学 | 4099篇 |
神经病学 | 20120篇 |
特种医学 | 13766篇 |
外国民族医学 | 220篇 |
外科学 | 37501篇 |
综合类 | 60970篇 |
现状与发展 | 84篇 |
一般理论 | 39篇 |
预防医学 | 23766篇 |
眼科学 | 10728篇 |
药学 | 39507篇 |
349篇 | |
中国医学 | 21955篇 |
肿瘤学 | 31472篇 |
出版年
2024年 | 1291篇 |
2023年 | 5808篇 |
2022年 | 15137篇 |
2021年 | 19065篇 |
2020年 | 14338篇 |
2019年 | 12510篇 |
2018年 | 13175篇 |
2017年 | 12012篇 |
2016年 | 11241篇 |
2015年 | 17238篇 |
2014年 | 21098篇 |
2013年 | 18892篇 |
2012年 | 27830篇 |
2011年 | 30838篇 |
2010年 | 19085篇 |
2009年 | 14818篇 |
2008年 | 19880篇 |
2007年 | 19354篇 |
2006年 | 19241篇 |
2005年 | 19069篇 |
2004年 | 12007篇 |
2003年 | 11174篇 |
2002年 | 9304篇 |
2001年 | 8201篇 |
2000年 | 8730篇 |
1999年 | 9095篇 |
1998年 | 5542篇 |
1997年 | 5547篇 |
1996年 | 4415篇 |
1995年 | 4130篇 |
1994年 | 3496篇 |
1993年 | 2205篇 |
1992年 | 3057篇 |
1991年 | 2621篇 |
1990年 | 2117篇 |
1989年 | 1857篇 |
1988年 | 1727篇 |
1987年 | 1467篇 |
1986年 | 1144篇 |
1985年 | 893篇 |
1984年 | 511篇 |
1983年 | 398篇 |
1982年 | 234篇 |
1981年 | 255篇 |
1980年 | 183篇 |
1979年 | 246篇 |
1978年 | 100篇 |
1977年 | 104篇 |
1975年 | 89篇 |
1974年 | 100篇 |
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
41.
M. Laurin Council Jennifer M. Gardner Cynthia Helms Ying Liu Lynn A. Cornelius Anne M. Bowcock 《Experimental dermatology》2009,18(5):485-487
Abstract: The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P = 0.002), particularly the R160W variant ( P = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer. 相似文献
42.
100例性病患者心理健康状况调查分析 总被引:3,自引:1,他引:2
目的:探讨性病患者的心理健康状况,为临床治疗和护理提供依据。方法:采用症状自评量表(SCL-90)对100例性病患者的心理健康状况进行测验。结果:100例性病患者SCL-90检测的阳性率为51%,阳性样本因子分居前的是敌对、强迫症状、抑郁、人际敏感。结论:性病患者广泛存在的心理问题,在药用治疗的同时应注意心理方面的治疗和疏导。 相似文献
43.
背景: 前期研究表明广西18~22岁少数民族学生体质量偏轻。
目的:拟进一步了解广西2645名少数民族学生体型及体质健康状况,寻找影响的关联因子。
设计、时间及地点:追踪调查,于2004-12/2007-12在广西民族大学完成。
对象:广西民族大学2003/2005三次体质健康测试的全体学生2 645人。男1 337人,女1308人,年龄为18~20岁,共15个民族。
方法:根据2003年教育部、体育总局《学生体质健康标准(试行方案)》和实施方法分为形态指标、技能指标和身体素质指标3大类。对2 645名少数民族身体机能与体质量指数变化的跟踪调查。
主要观察指标:身高、体质量、肺活量、立定跳远、坐位体前屈、体质量指数。
结果:①广西民族大学2003级学生大学3年期间男生身高、体质量增长率比全国同期多2.45%,身体形态发育正处于高峰期,女生成偏瘦型体型,身体形态发育情况总体欠佳。②男女学生在刚入校时肺活量机能较差,远远低于同期全国平均水平。3年后男生肺活量增长率为11.55%、女生肺活量增长率为27.72%,分别高于全国同期肺活量增长率。③坐位体前屈机能高于同期全国平均水平,男生呈逐年上升趋势,同期全国男性呈下降趋势;同期全国乡村女生均呈逐年上升趋势。④立定跳远机能提高较大,3年后增长率为18.15%,明显高于全国同期立定跳远增长率水平的2.61%。女生立定跳远机能总体不如全国同期水平。⑤体质量指数总体与同期全国乡村男女学生体质量指数比较稍低一些(P < 0.01)。
结论:2 645名少数民族学生发育正处于高峰期;肺活量机能不及全国同期平均水平。男女体质量指数分布有所不同,体质量偏轻者女生多于男生,表明学生营养状况总体欠佳。 相似文献
44.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
45.
Wan-Ling Ho Tien-Wu Yang Wei-Chu Chi Hong-Jen Chang Li-Min Huang Mei-Hwei Chang 《台湾医志》2005,104(6):398-401
BACKGROUND AND PURPOSE: This study investigated the characteristics of intussusception in Taiwanese children of different age groups, including the incidence, length of hospitalization and hospital costs. METHODS: Children with a diagnosis of intussusception who were hospitalized from 1999 through 2001 were identified from a nationwide health insurance claims database. The incidence of intussusception was calculated by age, gender, and season. Length of hospitalization and hospital costs were also analyzed. RESULTS: A total of 6988 cases of intussusception were identified in Taiwan from 1999 to 2001. Among them, 4859 cases occurred in children below 15 years of age. The average incidence among children below age 15 years was 34.5 per 100,000, with a peak incidence of 118.8 per 100,000 observed among children younger than 24 months old. The highest incidence of intussusception in Taiwanese children occurred between 12 and 24 months of age. According to the data for patients below 15 years of age hospitalized for intussusception in year 2000, males were more likely to be affected than females (61.3% vs 38.7%). Intussusception-related hospitalizations were rare in infants in the first few months of life, increased in those 6 to 12 months old, and peaked among children 1 to 3 years old. Among the 952 patients with intussusception admitted to hospitals in 2000, 297 (31.2%) received surgery, incurring higher median medical costs (New Taiwan Dollars [NT dollars] 42,265 or US dollars 1234) and longer median hospital stay (6.2 days) than the 655 patients who did not require surgery (NT dollars 6290 or US dollars 185 for hospitalization of 2.4 days). CONCLUSIONS: The study found that the incidence of intussusception peaked in the second year of life in Taiwanese children. There was also a male predominance and lack of seasonal variation in incidence. 相似文献
46.
Tumor metastasis to the pancreas is a rare but recognized cause of acute pancreatitis. Autopsy series have reported a 24-40% of pancreatic involvement in small cell lung cancer. However, only a very few cases of tumor-induced acute pancreatitis have been described. Budd-Chiari syndrome complicating lung cancer is a rarely reported condition. We report a 68-year-old woman with extensive small cell lung cancer with the unusual initial presentation of both acute pancreatitis and acute Budd-Chiari syndrome. This patient suffered from progressive epigastralgia for 3 weeks. Severe epigastralgia with radiation to back and progressive jaundice developed 2 days prior to admission. After admission, the liver enlarged rapidly and the ascites increased markedly. Chest roentgenogram showed a mass lesion over the left lower lung field. Poorly differentiated carcinoma cells were found in ascites and bone marrow. The patient died on the ninth day of hospitalization before chemotherapy was initiated. Prompt diagnosis of extensive-stage small cell lung cancer may allow early chemotherapy treatment which favorably influences recovery when the pancreatitis is mild. Although prolonged survival might have been expected had this patient recovered from pancreatitis and received chemotherapy, diagnosis was delayed due to difficulty in immunohistochemical diagnosis of the tumor and the unusual clinical presentation. The use of stains employing antibodies against neurofilament and neuron-specific enolase cell antigens is important for early diagnosis of poorly differentiated metastatic tumor cells. 相似文献
47.
BACKGROUND AND PURPOSE: This report describes the results of matched-unrelated-donor transplant for leukemia or myelodysplasia in the first 23 recipient children at a single medical center in Taiwan. METHODS: Between August 1994 and February 2003, 23 consecutive children with leukemia or myelodysplasia underwent matched-unrelated-donor bone marrow transplantation (BMT). The preparative regimen consisted of fractionated total body irradiation and cyclophosphamide in 6 patients; busulfan in combination with etoposide and cyclophosphamide in 4 patients who received cranial irradiation before transplantation; and busulfan and cyclophosphamide in 13 patients. RESULTS: Engraftment was achieved in 91.3% of cases. Acute graft-versus-host disease (GVHD) occurred in 18 of 21 patients who engrafted (85.7%). Event-free survival for all patients was 24.46 +/- 9.24%. The 12 children with standard-risk disease had better event-free survival than the 11 children with high-risk disease (46.88 +/- 15.03% vs 0%, p < or = 0.001). CONCLUSIONS: The major obstacles to successful matched-unrelated-donor BMT are acute GVHD, relapse and infection. Early transplantation and patient selection, prophylactic and therapeutic maneuvers for GVHD, as well as appropriate donor selection and virus prophylaxis may improve the results. 相似文献
48.
Pneumocephalus is a very rare complication of video-assisted thoracoscopic surgery (VATS). A 66-year-old man developed pneumocephalus secondary to thoracoscopic excision of a neurogenic tumor in the posterior mediastinum. Pneumocephalus was diagnosed by brain computed tomography. Neurosurgical intervention was performed after conservative therapy had failed. The patient's condition had resolved without any neurologic sequelae 2 years later. When a patient has a relatively large amount of chest tube drainage and neurologic symptoms after VATS, the possibility of pneumocephalus due to cerebrospinal fluid leakage must be considered. 相似文献
49.
50.