全文获取类型
收费全文 | 6251篇 |
免费 | 342篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 198篇 |
妇产科学 | 132篇 |
基础医学 | 803篇 |
口腔科学 | 148篇 |
临床医学 | 467篇 |
内科学 | 1267篇 |
皮肤病学 | 110篇 |
神经病学 | 458篇 |
特种医学 | 267篇 |
外科学 | 809篇 |
综合类 | 28篇 |
预防医学 | 747篇 |
眼科学 | 317篇 |
药学 | 430篇 |
中国医学 | 7篇 |
肿瘤学 | 408篇 |
出版年
2023年 | 31篇 |
2022年 | 69篇 |
2021年 | 147篇 |
2020年 | 76篇 |
2019年 | 118篇 |
2018年 | 138篇 |
2017年 | 114篇 |
2016年 | 99篇 |
2015年 | 159篇 |
2014年 | 165篇 |
2013年 | 208篇 |
2012年 | 349篇 |
2011年 | 356篇 |
2010年 | 195篇 |
2009年 | 166篇 |
2008年 | 322篇 |
2007年 | 354篇 |
2006年 | 348篇 |
2005年 | 348篇 |
2004年 | 353篇 |
2003年 | 320篇 |
2002年 | 296篇 |
2001年 | 217篇 |
2000年 | 193篇 |
1999年 | 163篇 |
1998年 | 66篇 |
1997年 | 52篇 |
1996年 | 69篇 |
1995年 | 40篇 |
1994年 | 31篇 |
1993年 | 22篇 |
1992年 | 97篇 |
1991年 | 74篇 |
1990年 | 74篇 |
1989年 | 80篇 |
1988年 | 93篇 |
1987年 | 62篇 |
1986年 | 61篇 |
1985年 | 60篇 |
1984年 | 54篇 |
1983年 | 29篇 |
1979年 | 30篇 |
1978年 | 31篇 |
1976年 | 23篇 |
1975年 | 22篇 |
1974年 | 23篇 |
1973年 | 38篇 |
1972年 | 20篇 |
1971年 | 19篇 |
1968年 | 19篇 |
排序方式: 共有6632条查询结果,搜索用时 9 毫秒
61.
Regeneration of severed rat tibial nerves was functionally and morphologically compared with repair following the use of 3 anastomosis techniques: collagen guide tubes, fibrin glue and conventional microsurgical sutures. In addition, one tibial nerve was crushed in some rats. At ten weekly intervals, functional recovery, assessed by sciatic nerve stimulated evoked contraction of the flexor digitorum muscle, was quicker and more complete following nerve crush than following the anastomosis techniques which were not different from each other. Ten weeks following the surgery, the retrograde transport morphological technique indicated that the anastomosis techniques were not different from each other. The number of labeled tibial motoneurons (tube and suture groups) was significantly less than the crush group, but the glue group was intermediate. Thus, although having less extensive recovery following crush, the quicker and easier techniques of nerve repair, i.e., collagen tubes or fibrin glue, produced comparable anatomical and functional recovery as the more time-consuming, technically demanding microsurgical repair with fine sutures. 相似文献
62.
Justin E Aldridge Jennifer A Gibbons Meghan M Flaherty Marisa L Kreider Jocelyn A Romano Edward D Levin 《Toxicological sciences》2003,76(1):3-20
While risk assessment models attempt to predict human risk to toxicant exposure, in many cases these models cannot account for the wide variety of human responses. This review addresses several primary sources of heterogeneity that may affect individual responses to drug or toxicant exposure. Consideration was given to genetic polymorphisms, age-related factors during development and senescence, gender differences associated with hormonal function, and preexisting diseases influenced by toxicant exposure. These selected examples demonstrate the need for additional steps in risk assessment that are needed to more accurately predict human responses to toxicants and drugs. 相似文献
63.
Downregulation of neuronal cdk5/p35 in opioid addicts and opiate-treated rats: relation to neurofilament phosphorylation. 总被引:5,自引:0,他引:5
Marcel Ferrer-Alcón Romano La Harpe José Guimón Jesús A García-Sevilla 《Neuropsychopharmacology》2003,28(5):947-955
Neuronal cyclin-dependent kinase-5 (Cdk5) and its neuron-specific activator p35 play a major role in regulating the cytoskeleton dynamics. Since opioid addiction was associated with hyperphosphorylation of neurofilament (NF) in postmortem human brains, this study was undertaken to assess the status of the cdk5/p35 complex and its relation with NF-H phosphorylation in brains of chronic opioid abusers. Decreased immunodensities of cdk5 (18%) and p35 (26-44%) were found in the prefrontal cortex of opioid addicts compared with matched controls. In the same brains, the densities of p25 (a truncated neurotoxic form of p35), phosphatase PP2Ac and mu-calpain were found unaltered. Acute treatment of rats with morphine (30 mg/kg, 2 h) increased the density of cdk5 (35%), but not that of p35, in the cerebral cortex. In contrast, chronic morphine (10-100 mg/kg for 5 days) induced marked decreases in cdk5 (40%) and p35 (47%) in rat brain. In brains of opioid addicts, the density of phosphorylated NF-H was increased (43%) as well as the ratio of phosphorylated to nonphosphorylated NF-H forms (two-fold). In these brains, phosphorylated NF-H significantly correlated with p35 (r=0.58) but not with cdk5 (r=0.03). The results suggest that opiate addiction is associated with downregulation of cdk5/p35 levels in the brain. This downregulation and the aberrant hyperphosphorylation of NF-H proteins might have important consequences in the development of neural plasticity associated with opiate addiction in humans. 相似文献
64.
65.
A Romano D Quaratino G Papa M Di Fonso A Venuti 《Archives of disease in childhood》1997,76(6):513-517
Eight two children with histories of maculopapular or urticarial rashes during aminopenicillin treatment underwent skin tests, patch tests, radioallergosorbent assays and, in some cases, oral challenges. Hypersensitivity was diagnosed in eight (9.8%): immediate in four with urticarial reactions and delayed (that is cell mediated) in four with maculopapular rashes. In 49 children (38 with maculopapular eruptions, 11 with urticarial/angiooedematous reactions), negative allergologic findings were confirmed using oral challenges with the suspected drug. Maculopapular rashes may reflect delayed hypersensitivity to aminopenicillins, which can be diagnosed on the basis of late intradermal reactions and/or patch test positivity. The allergen panel must include the suspected aminopenicillin itself, as many cases are side chain specific. Most patients with urticarial reactions (more typical of immediate hypersensitivity) will also react to penicilloyl polylysine and minor determinant mixture. The time elapsed between the reaction and testing must be considered if negative results emerge, because IgE mediated sensitivity (unlike cell mediated forms) declines in the absence of antigen exposure. 相似文献
66.
Felicetto Ferrara Vito D'Ambrosio Rosella Di Noto Giuseppina Mele Sabrina Giovine Luigia Romano 《Leukemia & lymphoma》1998,29(5):613-616
We describe a case of spontaneous splenic rupture occurred in a patient with acute lymphoblastic leukemia of Burkitt type before starting cytotoxic chemotherapy. Left hypochondrial pain radiating to the homolateral shoulder was the only clinical symptom. Emergency computed tomography showed splenic laceration and hemoperitoneum. The patient underwent immediate laparotomy with splenectomy and experienced an uneventful postoperative recovery. Eight days after surgery, chemotherapy could be administered and complete remission was achieved. Although spontaneous rupture of the spleen is rare in leukemia and related disorders, this diagnosis should be taken in account also when clinical symptoms are mild. Following immediate operative management, patients may completely recover and receive cytotoxic chemotherapy with substantial possibilities of achieving complete remission. 相似文献
67.
Franciosi C Caprotti R De Fina S Romano F Colombo G Uggeri F Sartori P Visintini G Uggeri F 《Minerva chirurgica》2000,55(10):665-671
BACKGROUND: Laparoscopic treatment of common bile duct (CBD) stones is gaining great acceptance worldwide, but actually it requires skills and technologies too expensive for a great part of general surgeons. So endoscopic removal of CBD stones before cholecystectomy is usually performed. Since 1991 in our department we started a policy of selective preoperative cholangiopancreatography (ERCP) in patients suspected for choledocholithiasis and waiting for laparoscopic cholecystectomy. METHODS: A retrospective study has been made on a population of 1100 patients who underwent elective laparoscopic cholecystectomy in the period between January 1991 and December 1997. They were 391 male and 719 female with a mean age of 52 years, 126 of whom (11.5%) were selected to have ERCP preoperatively because they had clinical, biochemical and ultrasound signs of the presence of common bile duct stones (CBDS). RESULTS: Successful cannulation of the CBD was achieved in 124 cases (98.4%), with failures due to ampullary diverticula. In 7 cases (5.5%) a precut was necessary to obtain cannulation. Sphincterotomy was performed in 113 patients (89.7%). In 93 patients (73.8%) stones were found (87 macrolithiasis and 6 microlithiasis); in 91 (97.8%) stones were removed in one (87) or two (4) endoscopic session. There were 2 major complications (one bleeding and one severe pancreatitis) due to ERCP or a sphincterotomy. Two patients developed symptoms from unsuspected common bile duct stones after LC and were removed endoscopically. No complications during LC were due to ERCP or ES. CONCLUSIONS: Selective preoperative ERCP is an effective way of clearing the CBD stones before laparoscopic cholecystectomy, with low rate of complications related to endoscopic and laparoscopic procedures, and short mean hospital stay (5.5 days), according to the concept of minimally invasive treatment. 相似文献
68.
HPV circulating tumor DNA to monitor the efficacy of anti‐PD‐1 therapy in metastatic squamous cell carcinoma of the anal canal: A case report 下载免费PDF全文
Luc Cabel François‐Clément Bidard Vincent Servois Wulfran Cacheux Pascale Mariani Emanuela Romano Mathieu Minsat Ivan Bieche Fereshteh Farkhondeh Emmanuelle Jeannot Bruno Buecher 《International journal of cancer. Journal international du cancer》2017,141(8):1667-1670
Squamous cell carcinoma of the anal canal (SCCA) is a rare HPV‐associated cancer with limited sensitivity to standard chemotherapy. In a phase 2 study, nivolumab, an anti PD‐1 immune checkpoint inhibitor, demonstrated significant efficacy as single‐agent therapy in metastatic SCCA patients. Nevertheless, imaging assessment by standard RECIST criteria of the efficacy of immune therapy can be difficult in some patients due to tumor immune cell infiltration, and biomarkers of treatment efficacy are needed. We have previously developed a quantitative droplet digital PCR (ddPCR) technique to detect HPV circulating tumor DNA (HPV ctDNA), with excellent sensitivity and specificity. Here, we report, for the first time, the kinetics of HPV ctDNA during therapy in a patient with metastatic SCCA, who obtained sustained partial response to single‐agent nivolumab. We observed an early and very significant decrease of HPV ctDNA during therapy from the baseline level of 3713 copies/ml plasma to 564 copies/ml plasma at 4 weeks, and 156 copies/ml at 6 weeks, followed by a plateau. This observation provides proof‐of‐concept that HPV ctDNA can be used as a noninvasive early dynamic biomarker to monitor the efficacy of new immunotherapy agents. 相似文献
69.
Silvia Di Giacomo Ester Percaccio Marco Gullì Adele Romano Annabella Vitalone Gabriela Mazzanti Silvana Gaetani Antonella Di Sotto 《Nutrients》2022,14(18)
Alzheimer’s disease (AD) is a progressive degenerative disorder of the central nervous system, characterized by neuroinflammation, neurotransmitter deficits, and neurodegeneration, which finally leads to neuronal death. Emerging evidence highlighted that hyperglycemia and brain insulin resistance represent risk factors for AD development, thus suggesting the existence of an additional AD form, associated with glucose metabolism impairment, named type 3 diabetes. Owing to the limited pharmacological options, novel strategies, especially dietary approaches based on the consumption of polyphenols, have been addressed to prevent or, at least, slow down AD progression. Among polyphenols, ferulic acid is a hydroxycinnamic acid derivative, widely distributed in nature, especially in cereal bran and fruits, and known to be endowed with many bioactivities, especially antioxidant, anti-inflammatory and antidiabetic, thus suggesting it could be exploited as a possible novel neuroprotective strategy. Considering the importance of ferulic acid as a bioactive molecule and its widespread distribution in foods and medicinal plants, the aim of the present narrative review is to provide an overview on the existing preclinical and clinical evidence about the neuroprotective properties and mechanisms of action of ferulic acid, also focusing on its ability to modulate glucose homeostasis, in order to support a further therapeutic interest for AD and type 3 diabetes. 相似文献
70.