全文获取类型
收费全文 | 108217篇 |
免费 | 9045篇 |
国内免费 | 4702篇 |
专业分类
耳鼻咽喉 | 1385篇 |
儿科学 | 1492篇 |
妇产科学 | 1476篇 |
基础医学 | 14443篇 |
口腔科学 | 2340篇 |
临床医学 | 11757篇 |
内科学 | 17095篇 |
皮肤病学 | 2355篇 |
神经病学 | 6478篇 |
特种医学 | 5215篇 |
外国民族医学 | 21篇 |
外科学 | 11387篇 |
综合类 | 12147篇 |
现状与发展 | 28篇 |
一般理论 | 24篇 |
预防医学 | 7281篇 |
眼科学 | 2862篇 |
药学 | 11252篇 |
66篇 | |
中国医学 | 4211篇 |
肿瘤学 | 8649篇 |
出版年
2024年 | 140篇 |
2023年 | 1071篇 |
2022年 | 1943篇 |
2021年 | 4477篇 |
2020年 | 2993篇 |
2019年 | 3134篇 |
2018年 | 3603篇 |
2017年 | 3193篇 |
2016年 | 3518篇 |
2015年 | 5120篇 |
2014年 | 6125篇 |
2013年 | 6491篇 |
2012年 | 9548篇 |
2011年 | 9900篇 |
2010年 | 6171篇 |
2009年 | 5255篇 |
2008年 | 6977篇 |
2007年 | 6577篇 |
2006年 | 6171篇 |
2005年 | 5527篇 |
2004年 | 4358篇 |
2003年 | 4239篇 |
2002年 | 3587篇 |
2001年 | 1896篇 |
2000年 | 1572篇 |
1999年 | 1407篇 |
1998年 | 923篇 |
1997年 | 800篇 |
1996年 | 709篇 |
1995年 | 613篇 |
1994年 | 578篇 |
1993年 | 402篇 |
1992年 | 439篇 |
1991年 | 404篇 |
1990年 | 345篇 |
1989年 | 306篇 |
1988年 | 213篇 |
1987年 | 226篇 |
1986年 | 191篇 |
1985年 | 133篇 |
1984年 | 118篇 |
1983年 | 70篇 |
1982年 | 79篇 |
1981年 | 75篇 |
1980年 | 59篇 |
1979年 | 40篇 |
1978年 | 23篇 |
1975年 | 22篇 |
1974年 | 18篇 |
1972年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Wendy Jo Svetanoff James A. Fraser Kayla B. Briggs Jessica K. Staszak Charlene Dekonenko Rebecca M. Rentea David Juang Pablo Aguayo Jason D. Fraser Charles L. Snyder Richard J. Hendrickson Shawn D. St. Peter Tolulope Oyetunji 《Journal of pediatric surgery》2021,56(6):1185-1189
IntroductionThere are many described technique to performing laparoscopic inguinal hernia repair in children. We describe our outcomes using a percutaneous internal ring suturing technique.MethodsA retrospective review of patients under 18 years old who underwent repair between January 2014 - March 2019 was performed. A percutaneous internal ring suturing technique, involving hydro-dissection of the peritoneum, percutaneous suture passage, and cauterization of the peritoneum in the sac prior to high ligation, was used. p < 0.05 was considered significant during the analysis.Results791 patients were included. The median age at operation was 1.9 years (IQR 0.37, 5.82). The median operative time for a unilateral repair was 21 min (IQR 16, 28), while the median time for a bilateral repair was 30.5 min (IQR 23, 41).In total, 3 patients required conversion to an open procedure (0.4%), 4 (0.6%) experienced post-operative bleeding, 9 (1.2%) developed a wound infection, and iatrogenic ascent of testis occurred in 10 (1.3%) patients. Twenty patients (2.5%) developed a recurrent hernia. All but two were re-repaired laparoscopically.ConclusionsThe use of percutaneous internal ring suturing for laparoscopic repair of inguinal hernias in the pediatric population is safe and effective with a low rate of complications and recurrence. 相似文献
992.
Hyemin Chung Sung-Han Kim Kyung-Wook Jo Tae Sun Shim Gil-Chun Park Ki-Hun Kim Sang-Oh Lee Sung-Gyu Lee 《Transplantation proceedings》2021,53(5):1694-1699
BackgroundWe encountered some cases of early-onset tuberculosis (TB) after liver transplant (LT), leading to further transmission to other immunocompromised patients. Therefore, we investigated the clinical characteristics and risk factors of early-onset TB after LT.MethodsAll adult patients with TB after LT from 1996 to 2019 were retrospectively enrolled. Our hospital did not screen for latent TB infection (LTBI) in LT recipients because of concerns regarding the potential hepatotoxicity of anti-TB medication. Patients were categorized into 2 groups based on the TB onset time after LT: early-onset TB (≤2 months) and late-onset TB (>2 months).ResultsOf 4301 LT recipients, 91 patients developed TB after LT (2.1%). The median time from LT to TB development was 9.4 months. Of these 91 patients, 11 were classified as having early-onset TB (12.1%). Patients with early-onset TB had a greater pretransplant TB history than patients with late-onset TB (36.4% vs 11.3%, P = .048).ConclusionThis unusual early-onset TB was more common in patients with a pretransplant TB history, suggesting the possibility of missed TB or full manifestation of the indolent course of TB after LT. Therefore, LT recipients with a pretransplant TB history should undergo thorough screening for active TB and consider prophylaxis. 相似文献
993.
Joseph R. Habib Benedict Kinny-Köster Floortje van Oosten Ammar A. Javed John L. Cameron Kelly J. Lafaro Richard A. Burkhart William R. Burns Jin He Elizabeth D. Thompson Elliot K. Fishman Christopher L. Wolfgang 《Surgery》2021,169(5):1026-1031
Most patients diagnosed with pancreatic cancer are classified as nonoperative candidates based on the contemporary guidelines of resectability. The advent of more potent control of systemic disease using neoadjuvant chemotherapy has enabled more aggressive operative interventions. In our multidisciplinary practice, patients with Stage III, locally advanced pancreatic cancer and superior mesenteric artery (SMA) encasement are now carefully triaged with high quality, preoperative imaging to determine if they can be considered candidates for operative resection with periadventitial dissection of the SMA. Patients displaying a “halo sign,” where the encased SMA remains fully patent and free from arterial invasion, are now candidates for SMA periadventitial dissection. This procedure involves the surgical stripping of the infiltrated neurolymphatic tissue off the SMA leaving behind a bare “skeletonized artery.” Alternatively, the “string sign” involving the SMA confers a more likely case of arterial invasion, where a complete oncologic resection cannot be achieved successfully. This method of patient selection in case of SMA involvement abandons the traditional metrics of circumferential degrees of the arterial encasement to guide surgical decisions. Our institutional approach has allowed us to meaningfully expand our operative methods of resection with the potential for improved longitudinal outcomes to pancreatic cancer patients who were deprived historically from the more effective and possibly curative treatment. 相似文献
994.
Cary Jo R. Schlick Tarik K. Yuce Anthony D. Yang Michael F. McGee David J. Bentrem Karl Y. Bilimoria Ryan P. Merkow 《Surgery》2021,169(2):240-247
BackgroundGuidelines recommend extended chemoprophylaxis for venous thromboembolism in high-risk patients having operations for inflammatory bowel disease. Quantifying patients' risk of venous thromboembolism, however, remains challenging. We sought (1) to identify factors associated with postdischarge venous thromboembolism in patients undergoing colorectal resection for inflammatory bowel disease and (2) to develop a postdischarge venous thromboembolism risk calculator to guide prescribing of extended chemoprophylaxis.MethodsPatients who underwent an operation for inflammatory bowel disease from 2012 to 2018 were identified from the American College of Surgeons National Surgical Quality Improvement Program for colectomy and proctectomy procedure targeted modules. Postdischarge venous thromboembolism included pulmonary embolism or deep vein thrombosis diagnosed after discharge from the index hospitalization. Multivariable logistic regression estimated the association of patient/operative factors with postdischarge venous thromboembolism. A postdischarge venous thromboembolism risk calculator was subsequently constructed.ResultsOf 18,990 patients, 199 (1.1%) developed a postdischarge venous thromboembolism within the first 30 postoperative days. Preoperative factors associated with postdischarge venous thromboembolism included body mass index (1.9% with body mass index ≥35 vs 0.8% with body mass index 18.5–24.9; odds ratio 2.34 [95% confidence interval 1.49–3.67]), steroid use (1.3% vs 0.7%; odds ratio 1.91 [95% confidence interval 1.37–2.66]), and ulcerative colitis (1.5% vs 0.8% with Crohn’s disease; odds ratio 1.76 [95% confidence interval 1.32–2.34]). Minimally invasive surgery was associated with postdischarge venous thromboembolism (1.2% vs 0.9% with open; odds ratio 1.42 [95% confidence interval 1.05–1.92]), as was anastomotic leak (2.8% vs 1.0%; odds ratio 2.24 [95% confidence interval 1.31–3.83]) and ileus (2.1% vs 0.9%; odds ratio 2.60 [95% confidence interval 1.91–3.54]). The predicted probability of postdischarge venous thromboembolism ranged from 0.2% to 14.3% based on individual risk factors.ConclusionPreoperative, intraoperative, and postoperative factors are associated with postdischarge venous thromboembolism after an operation for inflammatory bowel disease. A postdischarge venous thromboembolism risk calculator was developed which can be used to tailor extended venous thromboembolism chemoprophylaxis by individual risk. 相似文献
995.
Daniela de Queiroz Moura Ramon Rawache Marília Ferreira Gomes Garcia Nathalia Farias Vasconcelos Priscila Santos Gustavo Rego Coelho Thiago Luis da Paz Santos Duílio Reis da Rocha Filho Sonia Leite da Silva Eliana Regia Barbosa de Almeida Paula F.C.B.C. Fernandes João Batista Cerqueira José Huygens Parente Garcia Claudia Maria Costa de Oliveira 《Transplantation proceedings》2021,53(4):1345-1349
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation. 相似文献
996.
目的通过荟萃分析系统评价机器人胰十二指肠切除(RPD)与腹腔镜胰十二指肠切除(LPD)治疗壶腹部及其周围肿瘤的近期疗效。方法分别在Pubmed、Embase、Cochrane Library及Sinomed英文数据库中进行检索,检索词为"pancreaticoduodenectomy"、"duodenopanreatectomy"、"whipple"、"laparoscopic"、"robotic"、"Da Vinci";在万方数据知识服务平台、维普中文期刊服务平台及中国知网中文数据库中进行检索,检索词为胰十二指肠切除、腹腔镜、机器人、达芬奇,检索时限均从建库至2020年4月。分析比较RPD组与LPD组患者手术中转开腹率、术后并发症发生率以及术后住院时间等指标的差异,采用RevMan 5.3统计学软件进行荟萃分析。结果最终纳入4项回顾性队列研究共1001例患者,其中RPD组451例,LPD组550例。荟萃分析结果显示,RPD组与LPD组患者手术中转开腹率差异有统计学意义[优势比(OR)=0.35,95%CI:0.24~0.50,P<0.05]。而在术后总体并发症发生率(OR=1.23,95%CI:0.95~1.58,P>0.05)、出血发生率(OR=0.71,95%CI:0.50~1.00,P>0.05)、胰瘘发生率(OR=1.09,95%CI:0.80~1.49,P>0.05)、胃排空障碍发生率(OR=0.81,95%CI:0.57~1.14,P>0.05)以及术后住院时间(加权均数差=-2.87,95%CI:-1.44~1.70,P>0.05)方面两组进行比较,差异均无统计学意义(P>0.05)。结论RPD与LPD一样安全可行,且RPD可以降低中转开腹率、不增加手术并发症发生率。 相似文献
997.
998.
目的 采用溶剂浇铸法制备口腔溃疡双层膜剂,研究青黛表面改性前后对膜剂质量与药效的影响。方法 通过单因素实验设计和响应面优化法优选膜剂最佳处方,并对膜剂表面形貌、黏附时间、抗拉强度、含量测定以及体外药物释放等性能进行评估。进一步采用化学灼烧法建立大鼠口腔溃疡模型,考察膜剂对溃疡组织肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-1β(interleukin-1β,IL-1β)、IL-6以及口腔溃疡组织形态的影响。结果 空白隔离层确定为25 mg/mL的乙基纤维素乙醇溶液,载药膜最佳处方为63 mg/mL PVA17-88、55 mg/mL PVP K30、3.0 mg/mL明胶与0.047 mL/mL甘油。青黛表面改性后,双层膜剂比未改性双层膜剂具有更加光滑均一的外观、更高的含量均匀性和有效成分靛蓝释放率。药效学结果表明,与模型组相比,阳性组与青黛改性膜剂组显著降低了溃疡组织TNF-α、IL-1β、IL-6的含量(P<0.05),并减少了炎症细胞的浸润,溃疡组织愈合程度较高。结论 青黛改性之后的口腔溃疡双层膜剂具有更好的质量与更佳的疗效,具有较好的应用前景。 相似文献
999.
类风湿关节炎(RA)在中医学中属于“痹病”范畴,是临床中常见的难治性疾病,且呈年轻化趋势,迁延难愈。目前现代医学对RA的发病病因及机制尚不完全清楚。《素问·痹论》提出风寒湿三邪致痹,还有学者提出痰瘀致痹、肝肾亏虚等观点。李彦民主任医师根据多年临床经验提出RA的病机关键是络脉痹阻,其病机特点是虚实夹杂,临床辨证分为寒湿阻络型、湿热蕴结型、痰瘀互结型、气血两虚型、肝肾亏虚型等五型。分别采用祛邪通络和补虚通络等不同治则,辨证施法。李老师善用川乌、鸡血藤以及乌梢蛇等药以通络止痛,并主张辨证用药,内外兼治,多取良效。临床采用经验方仙龙汤,配合外用舒筋活络洗剂,且取得理想疗效。 相似文献
1000.
目的检测运用羟基磷灰石及β-磷酸三钙制备的双相钙磷陶瓷的生物相容性及其异位骨诱导效率。方法采用化学共沉淀法及过氧化氢发泡法,将羟基磷灰石及β-磷酸三钙以6∶4的比例在1 100 ℃条件下烧结3 h获得双相钙磷陶瓷,利用X线衍射评估材料组成成分。分离SD大鼠骨髓间充质干细胞,接种于双相钙磷陶瓷,通过扫描电镜、鬼笔环肽及DAPI染色观察细胞的黏附,CCK8法评估细胞增殖,碱性磷酸酶测定法评估骨髓间充质干细胞的碱性磷酸酶表达活性。将不含骨髓间充质干细胞的双相钙磷陶瓷置入比格犬竖脊肌内,于4、8、12周对样本行大体检测、组织染色,测算新骨生成率,从而评估双相钙磷陶瓷的异位骨诱导效率。结果成功制备双相钙磷陶瓷,X线衍射分析可见羟基磷灰石及β-磷酸三钙特异性的衍射峰。扫描电镜可见双相钙磷陶瓷表面广泛分布大孔及连通孔,孔壁粗糙不平,孔内可见均匀分布的微孔。鬼笔环肽及DAPI染色显示,骨髓充质干细胞在材料表面伸展黏附,共培养后逐渐从不规则形转变为均一的长梭形。CCK8法提示共培养后第1天,细胞活力降低,而第3、4、5、7天,细胞增殖活力逐渐增加。碱性磷酸酶活性检测提示,与对照组相比,共培养后第1、7天,双相钙磷陶瓷组的骨髓间充质干细胞可分泌更多的碱性磷酸酶。双相钙磷陶瓷顺利置入比格犬竖脊肌内,术后8周材料孔隙内可见骨样组织沉积,术后12周大孔成骨比例为0.77±0.11,孔内成骨面积比例为0.71±0.14。结论双相钙磷陶瓷具有良好的生物相容性及异位骨诱导效率。 相似文献