全文获取类型
收费全文 | 2502篇 |
免费 | 155篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 93篇 |
妇产科学 | 132篇 |
基础医学 | 407篇 |
口腔科学 | 30篇 |
临床医学 | 169篇 |
内科学 | 433篇 |
皮肤病学 | 93篇 |
神经病学 | 215篇 |
特种医学 | 128篇 |
外科学 | 353篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 110篇 |
眼科学 | 51篇 |
药学 | 99篇 |
肿瘤学 | 332篇 |
出版年
2023年 | 23篇 |
2022年 | 37篇 |
2021年 | 63篇 |
2020年 | 45篇 |
2019年 | 47篇 |
2018年 | 71篇 |
2017年 | 36篇 |
2016年 | 71篇 |
2015年 | 73篇 |
2014年 | 80篇 |
2013年 | 92篇 |
2012年 | 157篇 |
2011年 | 183篇 |
2010年 | 80篇 |
2009年 | 101篇 |
2008年 | 128篇 |
2007年 | 117篇 |
2006年 | 103篇 |
2005年 | 106篇 |
2004年 | 95篇 |
2003年 | 93篇 |
2002年 | 89篇 |
2001年 | 52篇 |
2000年 | 56篇 |
1999年 | 49篇 |
1998年 | 18篇 |
1997年 | 31篇 |
1996年 | 18篇 |
1995年 | 14篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 30篇 |
1991年 | 27篇 |
1990年 | 25篇 |
1989年 | 45篇 |
1988年 | 25篇 |
1987年 | 21篇 |
1986年 | 24篇 |
1985年 | 32篇 |
1984年 | 23篇 |
1982年 | 10篇 |
1980年 | 10篇 |
1979年 | 12篇 |
1977年 | 13篇 |
1976年 | 14篇 |
1975年 | 22篇 |
1974年 | 19篇 |
1969年 | 12篇 |
1967年 | 16篇 |
1966年 | 13篇 |
排序方式: 共有2672条查询结果,搜索用时 15 毫秒
101.
DNA Diagnostics of Hereditary Hearing Loss: A Targeted Resequencing Approach Combined with a Mutation Classification System 下载免费PDF全文
Manou Sommen Isabelle Schrauwen Geert Vandeweyer Nele Boeckx Jenneke van den Ende An Boudewyns Els De Leenheer Sandra Janssens Kathleen Claes Margriet Verstreken Nicola Strenzke Friederike Predöhl Wim Wuyts Geert Mortier Maria Bitner‐Glindzicz Tobias Moser Paul Coucke Matthew J. Huentelman Guy Van Camp 《Human mutation》2016,37(8):812-819
Although there are nearly 100 different causative genes identified for nonsyndromic hearing loss (NSHL), Sanger sequencing‐based DNA diagnostics usually only analyses three, namely, GJB2, SLC26A4, and OTOF. As this is seen as inadequate, there is a need for high‐throughput diagnostic methods to detect disease‐causing variations, including single‐nucleotide variations (SNVs), insertions/deletions (Indels), and copy‐number variations (CNVs). In this study, a targeted resequencing panel for hearing loss was developed including 79 genes for NSHL and selected forms of syndromic hearing loss. One‐hundred thirty one presumed autosomal‐recessive NSHL (arNSHL) patients of Western‐European ethnicity were analyzed for SNVs, Indels, and CNVs. In addition, we established a straightforward variant classification system to deal with the large number of variants encountered. We estimate that combining prescreening of GJB2 with our panel leads to a diagnosis in 25%–30% of patients. Our data show that after GJB2, the most commonly mutated genes in a Western‐European population are TMC1, MYO15A, and MYO7A (3.1%). CNV analysis resulted in the identification of causative variants in two patients in OTOA and STRC. One of the major challenges for diagnostic gene panels is assigning pathogenicity for variants. A collaborative database collecting all identified variants from multiple centers could be a valuable resource for hearing loss diagnostics. 相似文献
102.
Richard Biedermann Ekkehard Schleussner Angela Lauten Yvonne Heimann Thomas Lehmann Hans Proquitt Friederike Weschenfelder 《Geburtshilfe und Frauenheilkunde》2022,82(3):317
Introduction A common problem in the treatment of threatened preterm birth is the timing and the unrestricted use of antenatal corticosteroids (ACS). This study was performed to evaluate the independent effects of the distinct timing of antenatal corticosteroids on neonatal outcome parameters in a cohort of very low (VLBW; 1000 – 1500 g) and extreme low birth weight infants (ELBW; < 1000 g). We hypothesize that a prolonged ACS-to-delivery interval leads to an increase in respiratory complications. Materials and Methods Main data source was the prospectively collected single center data for the German nosocomial infection surveillance system (KISS) between 2015 and 2018. Multivariate regression analysis was performed to determine independent effects of the ACS-to-delivery interval on the need for ventilation, surfactant or the occurrence of bronchopulmonary dysplasia, neonatal sepsis or necrotizing enterocolitis. Subgroup analysis was performed for ELBW and VLBW neonates. Results A total of 239 neonates were included. We demonstrate a significantly increased risk of respiratory distress characterized by the need for ventilation (OR 1.045; CI 1.011 – 1.080) and surfactant administration (OR 1.050, CI 1.018 – 1.083) depending on the ACS-to-delivery interval irrespective of other confounders. Every additional day between ACS and delivery increased the risk for ventilation by 4.5% and for surfactant administration by 5%. Subgroup analysis revealed significant differences of respiratory complications in VLBW infants. Conclusions Our data strongly support the deliberate use and timing of antenatal corticosteroids in pregnancies with threatened preterm birth versus a liberal strategy. When given more than 7 days before birth, each day between application and delivery increases is relevant concerning major effects on the infant. Especially VLBW preterm neonates benefit from optimal timing. Key words: antenatal corticosteroids, preterm birth, VLWB, perinatal outcome, respiratory distress syndrome 相似文献
103.
Arsen Osipov Alex B.Blair Juliane Liberto Jianxin Wang Keyu Li Brian Herbst Yao Xu Shiqi Li Nan Niu Rufiaat Rashid Ding Ding Yanan Liu Zaiqi Wang Christopher L.Wolfgang Richard A.Burkhart Daniel Laheru Lei Zheng 《癌症生物学与医学(英文版)》2021,(1):206-214
Objective:Pancreatic ductal adenocarcinoma(PDAC)is a deadly malignancy,due in large part to its resistance to conventional therapies,including radiotherapy(RT).Despite RT exerting a modest antitumor response,it has also been shown to promote an immunosuppressive tumor microenvironment.Previous studies demonstrated that focal adhesion kinase inhibitors(FAKi)in clinical development inhibit the infiltration of suppressive myeloid cells and T regulatory(T regs)cells,and subsequently enhance effector T cell infiltration.FAK inhibitors in clinical development have not been investigated in combination with RT in preclinical murine models or clinical studies.Thus,we investigated the impact of FAK inhibition on RT,its potential as an RT sensitizer and immunomodulator in a murine model of PDAC.Methods:We used a syngeneic orthotopic murine model to study the effect of FAKi on hypofractionated RT.Results:In this study we showed that IN10018,a small molecular FAKi,enhanced antitumor response to RT.Antitumor activity of the combination of FAKi and RT is T cell dependent.FAKi in combination with RT enhanced CD8+T cell infiltration significantly in comparison to the radiation or FAKi treatment alone(P<0.05).FAKi in combination with radiation inhibited the infiltration of granulocytes but enhanced the infiltration of macrophages and T regs in comparison with the radiation or FAKi treatment alone(P<0.01).Conclusions:These results support the clinical development of FAKi as a radiosensitizer for PDAC and combining FAKi with RT to prime the tumor microenvironment of PDAC for immunotherapy. 相似文献
104.
The so-called "Postcholecystectomy Syndrome" may be due to various pathological biliary causes. The aim of this study was to evaluate the significance of the cystic duct stump syndrome and if so, how often a long (greater than 1.5 cm) cystic duct stump was an indication for reoperation on the bile ducts after cholecystectomy in our patients. Three hundred and twenty two patients underwent a second operation on the bile ducts after cholecystectomy in the last ten years. In 35 patients (10.8%) a striking findings was a long cystic duct stump (greater than 1.5 cm). In 24 of these patients, a pathological finding, in addition to the long cystic duct stump, was found on exploration. Out of these 24 patients there were 14 with common bile duct stones; 6 with stenosis of the sphincter of Oddi; 3 with chronic pancreatitis and in one patient hepatitis was the cause of the symptoms. From the remaining 11 patients 8 had a stone in a partial gall bladder or cystic duct stump. One patient had a fistula between the cystic duct stump and duodenum and one a suture granuloma. There was only one patient where a 1.5 cm long cystic duct stump remnant was the only pathological finding. Four years after reoperation this patient is still suffering from the same intermittent gastrointestinal symptoms. We conclude that the cystic duct stump is hardly ever a cause for recurrent symptoms in itself. Total excision of the cystic duct does not eliminate the existence of postcholecystectomy symptoms. 相似文献
105.
Purpose This study was designed to characterize rectal sensations by visualizing the internal and external anal sphincter and intra-anal
transport of bolus during elicited rectal sensations.
Methods The anal canal was visualized with real-time transperineal ultrasonography in 13 healthy female volunteers. Rectal sensations
were elicited by injecting water into the rectum. The ultrasound images were recorded on a videotape and analyzed offline.
Results The median time between an injection of water and the events studied was calculated in 105 rectal sensations. A relaxation
in the internal anal sphincter (4 seconds after the injection of water), an antegrade transport of bolus (4 seconds) into
the anal canal, and a contraction in the external anal sphincter (5 seconds) were observed before a sensation (6 seconds)
was reported. The antegrade flow continued until the distal internal anal sphincter contracted (18 seconds) and the bolus
moved in a retrograde transport direction (17 seconds) thereafter the sensation disappeared (18 seconds) and the external
anal sphincter relaxed (22 seconds). A significant correlation in time between the end of the sensation, contraction in the
internal anal sphincter, reversed flow of anal contents, and relaxation of the external anal sphincter was found (Pearson,
P<0.01).
Conclusions The results verified that the internal anal sphincter contributes to the perception of rectal sensations by a relaxation allowing
intra-anal bolus to increase the pressure on the anoderm during rectal contraction. A new observation is presented on the
time relation between contraction in the distal internal anal sphincter, reversed flow in the anal canal, and the end of rectal
sensations.
Presented at the meeting of the International Continence Society, Christchurch, New Zealand, November 27 to December 1, 2006.
Supported by Hitachi Ultrasound, Supfstrasse 24, 6300 Zug Switzerland provided the sonography system.
Reprints are not available. 相似文献
106.
107.
Palmoplantar keratoses and Bowen's disease in a Vietnam veteran: Could Agent Blue be implicated? 下载免费PDF全文
Armand B Cognetta Jr Christopher M Wolfe Alexander T Herbst 《The Australasian journal of dermatology》2016,57(2):e66-e68
Agent Blue was an arsenical herbicide used extensively in the Vietnam War. Arsenic is one of the known causes of acquired palmoplantar keratoderma (PPK). The most common manifestation of arsenic exposure in susceptible individuals is bilateral palmoplantar hyperkeratosis. We report a 67‐year‐old man with no known prior exposure to arsenic in the USA or family history of PPK who developed multiple squamous cell carcinoma in situ (SCCIS) and palmoplantar hyperkeratotic lesions beginning 23 years after service in Vietnam. The SCCIS were located on the trunk and extremities in both sun‐exposed and non‐sun‐exposed sites and his palmoplantar lesions were diagnosed concurrently with his SCCIS. He has continued to develop SCCIS since his first visit to our clinic 25 years ago. 相似文献
108.
109.
Andres Schmidt-Hebbel Carlos Gomez Carolina Aviles Elmar Herbst Maximiliano Scheu Gonzalo Ferrer Gonzalo Espinoza 《The Knee》2018,25(6):1129-1133
Background
Several reports of severe infections associated with allograft tissue in knee reconstructive surgery have led many surgeons to consider routine intraoperative culture of allograft tissue before implantation. Thus, the purpose of this study was to determine the prevalence of positive soft tissue allograft cultures in reconstructive knee surgery, and evaluate its association with surgical site infection.Methods
Retrospective study of 202 patients who underwent knee reconstructive ligament surgeries, including revisions, between January 2013 and July 2017. Intraoperative culture results were obtained and the report of a surgical site infection during follow-up was recorded. Patients without cultures were excluded. A priori power analysis was performed. The association between positive culture results and development of surgical site infection was evaluated using Fisher's Exact test (P?<?0.05).Results
A total of 300 allografts were implanted in 202 patients. Mean average follow-up was 32.9?±?12.5 (range 13 to 57.9) months. Sixteen patients had positive intraoperative allograft cultures (7.9%). The most frequently isolated organism was Bacillus species (six cultures); none of these patients presented with clinical signs of infection. Nine patients developed surgical site infections and were treated with oral antibiotics, and one patient developed septic arthritis that required surgical debridement of the implanted graft; all of these patients had a negative soft tissue allograft culture. No significant association was found between a positive culture and surgical site infection (P?=?0.43).Conclusion
There was no apparent association between positive intraoperative irradiated soft tissue allograft cultures and surgical site infection in reconstructive knee surgery. 相似文献110.
A hematopoietic growth factor, thrombopoietin, has a proapoptotic role in the brain 总被引:6,自引:0,他引:6 下载免费PDF全文
Ehrenreich H Hasselblatt M Knerlich F von Ahsen N Jacob S Sperling S Woldt H Vehmeyer K Nave KA Sirén AL 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(3):862-867
Central nervous and hematopoietic systems share developmental features. We report that thrombopoietin (TPO), a stimulator of platelet formation, acts in the brain as a counterpart of erythropoietin (EPO), a hematopoietic growth factor with neuroprotective properties. TPO is most prominent in postnatal brain, whereas EPO is abundant in embryonic brain and decreases postnatally. Upon hypoxia, EPO and its receptor are rapidly reexpressed, whereas neuronal TPO and its receptor are down-regulated. Unexpectedly, TPO is strongly proapoptotic in the brain, causing death of newly generated neurons through the Ras-extracellular signal-regulated kinase 1/2 pathway. This effect is not only inhibited by EPO but also by neurotrophins. We suggest that the proapoptotic function of TPO helps to select for neurons that have acquired target-derived neurotrophic support. 相似文献