全文获取类型
收费全文 | 26767篇 |
免费 | 1312篇 |
国内免费 | 251篇 |
专业分类
耳鼻咽喉 | 215篇 |
儿科学 | 516篇 |
妇产科学 | 629篇 |
基础医学 | 2816篇 |
口腔科学 | 541篇 |
临床医学 | 2299篇 |
内科学 | 7842篇 |
皮肤病学 | 566篇 |
神经病学 | 2358篇 |
特种医学 | 927篇 |
外科学 | 4325篇 |
综合类 | 62篇 |
一般理论 | 5篇 |
预防医学 | 977篇 |
眼科学 | 346篇 |
药学 | 1389篇 |
中国医学 | 43篇 |
肿瘤学 | 2474篇 |
出版年
2024年 | 27篇 |
2023年 | 224篇 |
2022年 | 464篇 |
2021年 | 777篇 |
2020年 | 493篇 |
2019年 | 644篇 |
2018年 | 767篇 |
2017年 | 588篇 |
2016年 | 731篇 |
2015年 | 791篇 |
2014年 | 1002篇 |
2013年 | 1379篇 |
2012年 | 2127篇 |
2011年 | 2096篇 |
2010年 | 1239篇 |
2009年 | 1113篇 |
2008年 | 1932篇 |
2007年 | 1830篇 |
2006年 | 1671篇 |
2005年 | 1676篇 |
2004年 | 1542篇 |
2003年 | 1358篇 |
2002年 | 1254篇 |
2001年 | 173篇 |
2000年 | 130篇 |
1999年 | 177篇 |
1998年 | 226篇 |
1997年 | 205篇 |
1996年 | 158篇 |
1995年 | 187篇 |
1994年 | 155篇 |
1993年 | 143篇 |
1992年 | 92篇 |
1991年 | 78篇 |
1990年 | 98篇 |
1989年 | 60篇 |
1988年 | 48篇 |
1987年 | 47篇 |
1986年 | 55篇 |
1985年 | 62篇 |
1984年 | 66篇 |
1983年 | 48篇 |
1982年 | 60篇 |
1981年 | 37篇 |
1980年 | 47篇 |
1979年 | 28篇 |
1977年 | 18篇 |
1975年 | 19篇 |
1974年 | 20篇 |
1972年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
101.
Mauro Calvani Claudia Alessandri Giuseppe Paolone Luciano Rosengard Antonino Di Caro David De Franco 《Pediatric allergy and immunology》1997,8(2):91-96
It is currently accepted that vinil infections may influence the development of atopy. In the present study we evaluated serum IgE levels as well as the prevalence of symptom-, indicative of utopic disease and EBV antibodies in 353 children aged from I month to 19 years. Antibodies against EBV were detected by immunofluorescence. IgE levels in serum were measured by en/. yme imimmoassay. Dividing ihe study population according to EBV seropositivity and age, we noted that the prevalence of high IgE levels (> 2 s. d.) was, in total, more frequent in the EBV negative (32. 9%) than in the positive subjects (27. 6%). Interestingly, this higher prevalence was found only in the groups aged under six, especially in the 7 to 29 month group, where it was statistically significant (p=0.037), whereas in the 6-19 year group the situation was reversed. Furthermore, selecting only the atopic children younger than 3 years of age with high IgE levels and clinical symptoms of atopy (wheezing and/or dermatitis) it was possible to demonstrate lower EBV seropositivity compared with the normal IgE controls for each group, even though these differences were not statistically significant. In conclusion, the results of our study suggest that, in our selected population, EBV infection in the first years of life is associated with a lower prevalence of high IgE levels. 相似文献
102.
Expression and activity of CYP2E1 in circulating lymphocytes are not altered in diabetic individuals
Laura Pucci Vera Chirulli Sandra Marini Daniela Lucchesi Giuseppe Penno Pier Giovanni Gervasi Stefano Del Prato Vincenzo Longo 《Pharmacological research》2005,51(6):561-565
Cytochrome P4502E1 (CYP2E1) plays an important role in ROS production thus favouring accelerated membrane lipid peroxidation. This isoform is strongly expressed in the liver but it can be also found in lymphocytes. As such, lymphocyte may provide a non-invasive accessible pool for screening CYP2E1 expression in man. We have, therefore, analysed CYP2E1 expression and activity in lymphocyte microsomes from 12 healthy controls, 11 type 1 and 12 type 2 diabetic subjects by using Western blot and enzymatic activities. Immunoblotting did not show difference among CYP2E1 protein bands in controls, type 1 and type 2 diabetics. To assess CYP2E1 activity we used the 7-ethoxy-4-trifluoromethylcoumarin (7-EFC), as a fluorescent substrate. The rate of deethylation of 7-EFC from controls did not differ from type 1 and type 2 diabetic subjects. The lack of any difference in CYP2E1 activity also was confirmed by the NADPH-dependent microsomal lipid peroxidation CCL4-induced assay showing similar peroxidation rates among controls and diabetic subjects. The results show that CYP2E1 expression/activity in lymphocytes is not enhanced in diabetes. 相似文献
103.
Mario Sanna Yogesh Jain Giuseppe De Donato Lorenzo RohitLauda Abdelkader Taibah 《Otology & neurotology》2004,25(5):797-804
OBJECTIVE: The objective of this study was to review the outcome of surgical management in patients of jugular paragangliomas. STUDY DESIGN: We conducted a retrospective case review. SETTING: Tertiary care otology and skull base center. MATERIALS AND METHODS: Fifty-five patients with the diagnosis of a jugular paraganglioma (Fisch Class C and D Glomus Jugulare) were managed over a period of 15 years. All patients with adequate follow up and complete records (53 cases) were reviewed with emphasis on the results of surgical management and the factors influencing them. INTERVENTION: All 53 patients were managed with a view to surgically extirpate the tumor. The primary approach was the infratemporal fossa approach-Type A used in the majority of the patients. In eight cases, the procedure was staged owing to the presence of large intracranial extension. Three patients required additional procedures to ameliorate the after-effects of lower cranial nerve resection. RESULTS: Gross total tumor removal was achieved in 49 patients. There were five cases of recurrence. Coupled with the residual tumors in five patients, the surgical control achieved was 83%. There was no perioperative mortality. There were two cases of postoperative cerebrospinal fluid leak, both of which required surgical exploration and closure. The facial nerve was resected in seven patients. The overall preservation rate of clinically uninvolved lower cranial nerves was 75%. CONCLUSIONS: The low level of complications along with a high surgical control achieved makes surgery the primary mode of treatment in the vast majority of these tumors, regardless of the size and location. 相似文献
104.
Mario Sanna Paolo Piazza Giuseppe Ditrapani Manoj Agarwal 《Otology & neurotology》2004,25(6):998-1005
OBJECTIVE: To present our experience with permanent preoperative balloon occlusion of the internal carotid artery while dealing with different abnormalities of the lateral skull base and a comparison with the results mentioned in the literature. STUDY DESIGN: Retrospective case review. SETTING: Private neurotologic and skull base tertiary referral center. PATIENTS: Fifteen patients who underwent preoperative balloon occlusion of the internal carotid artery and surgery subsequently for various abnormalities of the lateral skull base between 1989 and 2002. INTERVENTIONS: Each patient was subjected to four-vessel angiography along with the manual cross-compression test and balloon test occlusion to assess the efficacy of the collateral circulation. After angiography, each patient underwent a preoperative balloon occlusion, after which a lateral skull base procedure was performed for removal of the abnormality. MAIN OUTCOME MEASURES: Only those patients showing evidence of adequate collateral cerebral circulation and a less than 1-second delay between the angiographic phases of the two cerebral hemispheres on angiography were considered fit for preoperative balloon occlusion. While under going the preoperative balloon occlusion, the patients were clinically assessed for the development of any neurologic symptoms and signs. Long-term follow-up after surgery was also based on the development of symptoms and signs of neurovascular compromise. RESULTS: A major complication in the form of long-lasting hemiplegia occurred in one patient (6.7%). This complication was the result of technical factors rather than an effect of cerebral ischemia, because it was caused by an intimal dissection produced by the catheter. A defect in the visual field occurred in one patient (6.7%) that resolved partially after antiplatelet therapy. There was no mortality in our series related to preoperative balloon occlusion of the internal carotid artery. CONCLUSION: Preoperative balloon occlusion of the internal carotid artery can still be considered a viable option for the management of the internal carotid artery during lateral skull base surgery. Proper preoperative evaluation of the adequacy and efficacy of the collateral cerebral circulation reduces the chances of postoperative neurovascular complications. 相似文献
105.
Nocturnal frontal lobe epilepsy (NFLE) has become clinically relevant in recent years. NFLE represents a spectrum of clinical manifestations, ranging from brief, stereotyped, sudden arousals, often recurring several times per night, sometimes with a quasi-periodic pattern, to more complex dystonic-dyskinetic seizures and to prolonged "somnambulic" behaviour. Episodes of increasing intensity have been labelled as paroxysmal arousal (PA), nocturnal paroxysmal dystonia (NPD) and episodic nocturnal wandering (ENW). NFLE affects both sexes with a higher prevalence for men, is frequently cryptogenetic and displays a strong familial trait for parasomnias and epilepsy (NFLE). Seizures appear more frequently between 14 and 20 years of age, but can affect any age and tend to increase in frequency during life. Interictal and ictal scalp electroencephalography (EEG) are often normal, the use of sphenoidal leads may be helpful. Carbamazepine taken at night is often effective at low doses, but a third of the patients are resistant to anti-epileptic drugs (AED) treatment. A familial form, characterized by an autosomal dominant transmission, has also been described. Autosomal dominant nocturnal frontal lobe epilepsy is a genetic variant of NFLE, in itself both clinically and biologically heterogeneous. NFLE should be suspected in the presence of frequent stereotyped paroxysmal nocturnal motor events arising or persisting into adulthood. Videopolysomnography is mandatory to confirm the diagnosis. 相似文献
106.
Simona Soverini Giovanni Martinelli Gianantonio Rosti Simona Bassi Marilina Amabile Angela Poerio Barbara Giannini Elena Trabacchi Fausto Castagnetti Nicoletta Testoni Simona Luatti Antonio de Vivo Daniela Cilloni Barbara Izzo Milena Fava Elisabetta Abruzzese Daniele Alberti Fabrizio Pane Giuseppe Saglio Michele Baccarani 《Journal of clinical oncology》2005,23(18):4100-4109
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered. 相似文献
107.
Andrea Pession Maria Grazia Valsecchi Giuseppe Masera Willem A Kamps Edina Magyarosy Carmelo Rizzari Elisabeth R van Wering Luca Lo Nigro Anna van der Does Franco Locatelli Giuseppe Basso Maurizio Aricò 《Journal of clinical oncology》2005,23(28):7161-7167
PURPOSE: Between September 1991 and May 1997, within the International Berlin-Frankfurt-Muenster Study Group (I-BFM-SG), a randomized study was performed aimed at assessing the efficacy of prolonged use of high-dose l-asparaginase (HD-l-ASP) during continuation therapy in children with standard risk (SR) acute lymphoblastic leukemia (ALL), treated with a reduced BFM-type chemotherapy. PATIENTS AND METHODS: The Italian, Dutch, and Hungarian groups participated in this study denominated IDH-ALL-91, and 494 children were enrolled. Treatment consisted of a BFM-type modified backbone with omission of the IB part in induction and elimination of two doses of anthracyclines during reinduction in both arms at the beginning of continuation therapy. Patients were randomly assigned to receive (YES-ASP) or not (NO-ASP) 20 weekly HD-l-ASP (25,000 IU/m2). RESULTS: The event-free-survival and overall survival probabilities at 10 years for the entire group were 82.5% (1.8) and 90.3% (1.3), respectively. Of the 490 patients eligible for random assignment, 355 (72.4%) were randomly assigned (178 YES-ASP and 177 NO-ASP). After a median follow-up of 9 years, the probability of disease-free survival at 10 years was 87.5% (SE, 2.5) for YES-ASP arm versus 78.7% (SE, 3.3) for NO-ASP arm (P = .03). In multivariate analysis, NO-ASP arm (P = .03), male sex (P = .004), and age older than 10 years (P = .0003) had a significantly adverse impact on outcome. CONCLUSION: In this subset of patients, selected with criteria not including monitoring of minimal residual disease, application of extended HD-l-ASP may improve prognosis, compensating reduced leukemia control that results from adoption of a reduced-intensity BFM-backbone for treatment of children with SR ALL. 相似文献
108.
Stefania Momi Jessica Canino Mauro Vismara Luca Galgano Emanuela Falcinelli Giuseppe Guglielmini Giulia Ciarrocca Taranta Gianni Francesco Guidetti Paolo Gresele Mauro Torti Ilaria Canobbio 《Haematologica》2022,107(6):1374
Deep vein thrombosis results from the cooperative action of leukocytes, platelets, and endothelial cells. The proline-rich tyrosine kinase Pyk2 regulates platelet activation and supports arterial thrombosis. In this study, we combined pharmacological and genetic approaches to unravel the role of Pyk2 in venous thrombosis. We found that mice lacking Pyk2 almost completely failed to develop deep venous thrombi upon partial ligation of the inferior vena cava. Pyk2-deficient platelets displayed impaired exposure of phosphatidylserine and tissue factor expression by endothelial cells and monocytes was completely prevented by inhibition of Pyk2. In human umbilical vein endothelial cells (HUVEC), inhibition of Pyk2 hampered IL-1β-induced expression of VCAM and P-selectin, and von Willebrand factor release. Pyk2-deficient platelets showed defective adhesion on von Willebrand factor and reduced ability to bind activated HUVEC under flow. Moreover, inhibition of Pyk2 in HUVEC strongly reduced platelet adhesion. Similarly, Pyk2-deficient neutrophils were unable to efficiently roll and adhere to immobilized endothelial cells under venous flow conditions. Moreover, platelets and neutrophils from Pyk2-knockout mice showed defective ability to form heterogeneous aggregates upon stimulation, while platelet monocyte interaction occurred normally. Consequently, platelet neutrophil aggregates, abundant in blood of wild-type mice upon inferior vena cava ligation, were virtually undetectable in Pyk2-knockout mice. Finally, we found that expression of Pyk2 was required for NETosis induced by activated platelets. Altogether our results demonstrate a critical role of Pyk2 in the regulation of the coordinated thromboinflammatory responses of endothelial cells, leukocytes and platelets leading to venous thrombosis. Pyk2 may represent a novel promising target in the treatment of deep vein thrombosis. 相似文献
109.
Hepatitis B virus (HBV) is DNA-based virus, member of the Hepadnaviridae family, which can cause liver disease and increased risk of hepatocellular carcinoma (HCC) in infected individuals, replicating within the hepatocytes and interacting with several cellular proteins. Chronic hepatitis B can progressively lead to liver cirrhosis, which is an independent risk factor for HCC. Complications as liver decompensation or HCC impact the survival of HBV patients and concurrent HDV infection worsens the disease. The available data provide evidence that HBV infection is associated with the risk of developing HCC with or without an underlying liver cirrhosis, due to various direct and indirect mechanisms promoting hepatocarcinogenesis. The molecular profile of HBV-HCC is extensively and continuously under study, and it is the result of altered molecular pathways, which modify the microenvironment and lead to DNA damage. HBV produces the protein HBx, which has a central role in the oncogenetic process. Furthermore, the molecular profile of HBV-HCC was recently discerned from that of HDV-HCC, despite the obligatory dependence of HDV on HBV. Proper management of the underlying HBV-related liver disease is fundamental, including HCC surveillance, viral suppression, and application of adequate predictive models. When HBV-HCC occurs, liver function and HCC characteristics guide the physician among treatment strategies but always considering the viral etiology in the treatment choice. 相似文献
110.
Stefan Lucian Popa Dinu Iuliu Dumitrascu Cristina Pop Teodora Surdea-Blaga Abdulrahman Ismaiel Giuseppe Chiarioni Dan Lucian Dumitrascu Vlad Dumitru Brata Simona Grad 《Nutrients》2022,14(10)
Functional dyspepsia represents one of the most common and prevalent disorders of the brain–gut interaction, with a large number of widespread risk factors being identified. With an intricate pathogenesis and symptomatology, it heavily impacts the quality of life and, due to the limited efficacy of traditional pharmacological agents, patients are likely to seek other medical and non-medical solutions to their problem. Over the last few years, significant research in this domain has emphasized the importance of various psychological therapies and nutritional recommendations. Nevertheless, a correlation has been established between functional dyspepsia and food intolerances, with more and more patients adopting different kinds of exclusion diets, leading to weight loss, restrictive eating behaviour and an imbalanced nutritional state, further negatively impacting their quality of life. Thus, in this systematic review, we aimed at analysing the impact and efficiency of certain exclusion diets undertook by patients, more precisely, the gluten-free diet and the low-FODMAP diet. 相似文献