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51.
52.
Vanillin crystals in a saturated aqueous solution disappear and a second liquid phase emerges when the temperature is raised above 51 degrees C. The phenomenon has been investigated with crystallization and equilibration experiments, using DSC, TGA, XRD and hot-stage microscopy for analysis. The new liquid solidifies on cooling, appears to melt at 51 degrees C, and has a composition corresponding to a dihydrate. However, no solid hydrate can be detected by XRD, and it is shown that the true explanation is that a liquid-liquid phase separation occurs above 51 degrees C where the vanillin-rich phase has a composition close to a dihydrate. To our knowledge, liquid-liquid phase separation has not previously been reported for the system vanillin-water, even though thousands of tonnes of vanillin are produced globally every year. 相似文献
53.
Muacević-Katanec D Bradamante V Poljicanin T Reiner Z Babić Z Simeon-Rudolf V Katanec D 《Arzneimittel-Forschung》2007,57(10):647-653
Human paraoxonase (PON1) is a serum high-density lipoprotein-associated phosphotriesterase. High-density lipoprotein (HDL) plays the role of a carrier and the site of action of this enzyme. According to a majority of authors, PON1 acts as an antioxidant, preventing low-density lipoprotein (LDL) peroxidation. However, due to the fact that in vivo serum PON1 is predominantly associated with HDL, its major physiological role might be to protect HDL, rather than LDL, from oxidation. Nevertheless, the physiological substrate of PON1 still remains to be discovered. The objective of this study was to determine changes in PON1 activity during treatment with simvastatin (CAS 79902-63-9, Lipex) in patients with type IIa and/or IIb hyperlipoproteinemia. PON1 activity was assessed in 32 patients with hyperlipoproteinemia type IIa or IIb with an LDL cholesterol concentration higher than 4.2 mmol/l. Patients received simvastatin in a daily dose of 20 mg. The lipid status and PON1 activity were assessed at baseline, as well as 3 and 6 months after the beginning of treatment. The study demonstrated a statistically significant lipid lowering effect of simvastatin on total and LDL cholesterol, and an increase in PON1 activity in patients with both types of hyperlipoproteinemia. No statistically significant correlation was observed either between changes in PON1 activity and HDL, HDL2, HDL3 and LDL cholesterol and triglyceride levels, or between their first differences in patients with both type IIa and IIb hyperlipoproteinemia. The obtained results suggest that the antioxidant properties of simvastatin might be caused by a mechanism independent of apoAI-containing lipoprotein concentration. The antioxidant properties of simvastatin, which play an important role in HDL protection from oxidation, could be the mechanism inducing the increase in PON1 activity. 相似文献
54.
55.
Pauline Delnatte Davor Ojkic Josepha DeLay Doug Campbell Graham Crawshaw 《Avian pathology》2013,42(2):114-128
56.
Chanchao Lorthongpanich Daniel M. Messerschmidt Siew Wee Chan Wanjin Hong Barbara B. Knowles Davor Solter 《Genes & development》2013,27(13):1441-1446
Cellular localization of the Yes-associated protein (YAP) is dependent on large tumor suppressor (LATS) kinase activity and initiates lineage specification in the preimplantation embryo. We temporally reduced LATS activity to disrupt this early event, allowing its reactivation at later stages. This interference resulted in an irreversible lineage misspecification and aberrant polarization of the inner cell mass (ICM). Complementation experiments revealed that neither epiblast nor primitive endoderm can be established from these ICMs. We therefore conclude that precisely timed YAP localization in early morulae is essential to prevent trophectoderm marker expression in, and lineage specification of, the ICM. 相似文献
57.
Jakov?Me?trovi? Zenon?Pogoreli?Email author Irena?Drmi?-Hofman Katarina?Vilovi? Davor?Todori? Marijana?Popovi? 《Surgery today》2017,47(3):393-398
Purpose
The aim of this study was to investigate the effect of urapidil and low-molecular weight heparin (LMWH) on testicular torsion–detorsion injury in rats.Methods
Thirty-two male Sprague–Dawley rats were used. In the torsion–detorsion (T/D) group, the left testis was twisted at 720° for 3 h. After 3 h of reperfusion, the testis was removed. Urapidil or LMWH was administered intraperitoneally 30 min before detorsion in the treatment groups.Results
Unilateral testicular torsion–detorsion caused significant increases in the malondialdehyde level and apoptosis and significant decreases in the superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in ipsilateral testes (p < 0.001). The rats treated with urapidil had a significant decrease in the malondialdehyde level and apoptosis and significant increases in the SOD and GPx activities in ipsilateral testes compared to the T/D group (p < 0.001). Animals treated with LMWH showed non-significant reductions in malondialdehyde levels and apoptosis compared to the T/D group. In addition, no significant difference in the SOD activities (p = 0.52) between the groups was found. The increase in the GPx activities was significant in the LMWH group compared to the T/D group (p < 0.001).Conclusion
The administration of urapidil before detorsion prevents ischemia/reperfusion cellular damage in testicular tissue. LMWH was not found to have a beneficial effect on testicular T/D injury in rats.58.
Marco Metra Marianna Adamo Daniela Tomasoni Alexandre Mebazaa Antoni Bayes-Genis Magdy Abdelhamid Stamatis Adamopoulos Stefan D. Anker Johann Bauersachs Yuri Belenkov Michael Böhm Tuvia Ben Gal Javed Butler Alain Cohen-Solal Gerasimos Filippatos Finn Gustafsson Loreena Hill Tiny Jaarsma Ewa A. Jankowska Mitja Lainscak Yuri Lopatin Lars H. Lund Theresa McDonagh Davor Milicic Brenda Moura Wilfried Mullens Massimo Piepoli Marija Polovina Piotr Ponikowski Amina Rakisheva Arsen Ristic Gianluigi Savarese Petar Seferovic Rajan Sharma Thomas Thum Carlo G. Tocchetti Sophie Van Linthout Cristiana Vitale Stephan Von Haehling Maurizio Volterrani Andrew J.S. Coats Ovidiu Chioncel Giuseppe Rosano 《European journal of heart failure》2023,25(7):1115-1131
Acute heart failure is a major cause of urgent hospitalizations. These are followed by marked increases in death and rehospitalization rates, which then decline exponentially though they remain higher than in patients without a recent hospitalization. Therefore, optimal management of patients with acute heart failure before discharge and in the early post-discharge phase is critical. First, it may prevent rehospitalizations through the early detection and effective treatment of residual or recurrent congestion, the main manifestation of decompensation. Second, initiation at pre-discharge and titration to target doses in the early post-discharge period, of guideline-directed medical therapy may improve both short- and long-term outcomes. Third, in chronic heart failure, medical treatment is often left unchanged, so the acute heart failure hospitalization presents an opportunity for implementation of therapy. The aim of this scientific statement by the Heart Failure Association of the European Society of Cardiology is to summarize recent findings that have implications for clinical management both in the pre-discharge and the early post-discharge phase after a hospitalization for acute heart failure. 相似文献
59.
Cabov T Krmpotić M Grgurević J Perić B Jokić D Manojlović S 《Wiener klinische Wochenschrift》2005,117(21-22):780-783
Odontomas as a group are the most common odontogenic neoplasms. They are mixed lesions containing fully formatted dental tissues, both epithelial and mesenchymal, and are usually found during a routine radiographic examination or as a factor in noneruption. Odontomas can be divided into two types: the complex and the compound odontoma. Both types are composed of enamel, dentin, cementum and pulp tissues, but in complex odontomas the tissues are arranged in a haphazard fashion with no discernible dental structures, whereas in compound odontomas the dental tissues exist in a more regular pattern so that the lesion consists of tooth-like structures. We report a case of a 23-year-old man with a large complex odontoma involving the left maxilla and maxillary sinus with clinical, radiographic and histological findings. Because of the size of the mass and its clinical course, benign neoplasms were considered in the differential diagnosis. Surgery was the treatment of choice, and recurrence of the lesion is not expected. 相似文献
60.
Olfaction is an essential chemosensory system in the living world. Although less appreciated in humans, smell impairment significantly
affects many aspects of quality of life. Smell disorders may be caused by an impaired nasal airway or by lesions in the olfactory
system, leading to reduced or distorted smell perception. The most common causes of smell disorders are aging, upper respiratory
tract infection, sinonasal disease, and head trauma. Recovery is rarely complete. Counseling is important in progressive or
severe smell loss. In patients with distorted smell perception, antidepressant medication is sometimes necessary. Best response
to treatment is achieved for nasal obstruction and sinonasal inflammatory disease. Treatment of olfactory impairment caused
by sinonasal disease includes medication with topical and systemic steroids, or surgery for refractory cases. Although there
are reports that surgical resection of olfactory neurons may lead to reinnervation and recovery of smell, adequate treatment
of the smell loss remains an unmet need. 相似文献