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731.
Determination of phenolic compounds in fennel by HPLC and HPLC-MS using a monolithic reversed-phase column 总被引:4,自引:0,他引:4
Krizman M Baricevic D Prosek M 《Journal of pharmaceutical and biomedical analysis》2007,43(2):481-485
A reversed-phase high-performance liquid chromatography (HPLC) method for analyzing phenolic compounds in fennel (Foeniculum vulgare) has been developed. The use of a monolithic column with short dimensions in combination with optimized chromatographic conditions allows over 100 samples per day to be analyzed. Chromatographic parameters such as column temperature and injection volume, were found to be crucial in obtaining adequate selectivity and resolution, consequently allowing short run times. The method was validated for the major phenolic compounds present in fennel plant material: 3-O-caffeoylquinic acid (3-CQA), chlorogenic acid, 4-O-caffeoylquinic acid (4-CQA), eriocitrin, rutin, miquelianin, 1,3-O-dicaffeoylquinic acid (1,3-diCQA), 1,5-O-dicaffeoylquinic acid (1,5-diCQA), 1,4-O-dicaffeoylquinic acid (1,4-diCQA) and rosmarinic acid. The limits of detection (LOD) and the limits of quantitation (LOQ) ranged from 0.05 to 1.0 microg/mL and from 0.15 to 2.5 microg/mL, respectively. With some adaptation, the extraction procedure could be even less invasive, which is useful in screening work. 相似文献
732.
Schwarz P Bretagne S Gantier JC Garcia-Hermoso D Lortholary O Dromer F Dannaoui E 《Journal of clinical microbiology》2006,44(2):340-349
Mucormycosis is an emerging infection associated with a high mortality rate. Identification of the causative agents remains difficult and time-consuming by standard mycological procedures. In this study, internal transcribed spacer (ITS) sequencing was validated as a reliable technique for identification of Zygomycetes to the species level. Furthermore, species identification directly from infected tissues was evaluated in experimentally infected mice. Fifty-four Zygomycetes strains belonging to 16 species, including the most common pathogenic species of Rhizopus spp., Absidia spp., Mucor spp., and Rhizomucor spp., were used to assess intra- and interspecies variability. Ribosomal DNA including the complete ITS1-5.8S-ITS2 region was amplified with fungal universal primers, sequenced, and compared. Overall, for a given species, sequence similarities between isolates were >98%. In contrast, ITS sequences were very different between species, allowing an accurate identification of Zygomycetes to the species level in most cases. Six species (Rhizopus oryzae, Rhizopus microsporus, Rhizomucor pusillus, Mucor circinelloides, and Mucor indicus) were also used to induce disseminated mucormycosis in mice and to demonstrate that DNA extraction, amplification of fungal DNA, sequencing, and molecular identification were possible directly from frozen tissues. 相似文献
733.
Walter Fiers Marina De Filette Karim El Bakkouri Bert Schepens Kenny Roose Michael Schotsaert Ashley Birkett Xavier Saelens 《Vaccine》2009
Human influenza causes substantial morbidity and mortality. Currently, licensed influenza vaccines offer satisfactory protection if they match the infecting strain, but they come with significant drawbacks. These vaccines are derived from prototype viruses, containing the hemagglutinin of influenza viruses that are likely to cause the next epidemic. Their usefulness against a future pandemic, however, remains problematic. A vaccine based on the ectodomain of influenza matrix protein 2 (M2e) could overcome these drawbacks. M2e is highly conserved in both human and avian influenza A viruses. The low immunogenicity against natural M2e can be overcome by fusing M2e to an appropriate carrier such as Hepatitis B virus-derived virus-like particles. Such chimeric particles can be produced in a simple and safe bacterial expression system, requiring minimal biocontainment, and can be obtained in a pure form. Experiments in animal models have demonstrated that M2e-based vaccines induce protection against a lethal challenge with various influenza A virus subtypes. Furthermore, the production and use of an effective M2e-vaccine could be implemented at any time regardless of seasonality, both in an epidemic as well as in a pandemic preparedness program. In animal models, M2e-vaccines administered parenterally or intranasally protect against disease and mortality following challenge with various influenza A strains. Adjuvants suitable for human use improve protection, which correlates with higher anti-M2e antibody responses of defined subtypes. Recently, Phase I clinical studies with M2e-vaccines have been completed, indicating their safety and immunogenicity. Further clinical development of this universal influenza A vaccine candidate is being pursued in order to validate its protective efficacy in humans. 相似文献
734.
This article describes the development of a 5-item scale that assesses family caregivers' self-efficacy in communicating with physicians about ill family members (Perceived Efficacy in Caregiver-Physician Interactions-PECPI) in the context of an evaluation study of an online training in health care communication skills for caregivers. A national sample of 197 self-identified family caregivers participated in an online webinar and completed a brief evaluation instrument before and immediately after the training. Results indicated that the webinar was effective in increasing perceived self-efficacy and self-reported knowledge about and level of preparation for medical visits. Principal component analysis indicates that the PECPI is unidimensional with a Cronbach's alpha of .91. 相似文献
735.
Barcellos RB Almeida SE Sperhacke RD Verza M Rosso F Medeiros RM Perizzolo PF Cortez-Herrera E Rossetti ML 《Journal of virological methods》2011,177(1):38-43
Persistent infection with high-risk human papillomavirus (HR-HPV) has been associated with cervical cancer. Developing assays for the identification of these viral types is of great importance for monitoring patients and controlling strategies. The development of the MCHA (microplate colorimetric hybridization assay), a PCR-based method for identifying six of the most common HR-HPV types (HPV 16, 18, 31, 33, 39 and 45) is described. The MCHA combines the amplification with the GP5+/GP6+ consensus primers followed by PCR reverse hybridization with specific probes and detection through a colorimetric assay. The performance of the MCHA was evaluated using 108 DNA samples typed previously by the PapilloCheck®. The agreement between both methods was 69.4% for HPV 16; 79.1% for HPV 45; 82.4% for HPV 18; 93.6% for HPV 31; 87.9% for HPV 33, and 17.6% for HPV 39. The assay had higher sensitivity than the Papillocheck®, particularly for identifying HPV 16 and 18. The MCHA seemed to be sensitive and specific for the identification of the most prevalent HPV types in invasive cervical cancer, HPV 16, 18, 45, 33 and 31. It requires low-cost reagents and common laboratory apparatus. 相似文献
736.
737.
Gastric outlet obstruction secondary to pancreatic
cancer 总被引:8,自引:0,他引:8
Wong YT Brams DM Munson L Sanders L Heiss F Chase M Birkett DH 《Surgical endoscopy》2002,16(2):310-312
Background: Gastric outlet obstruction in patients with pancreatic cancer has a grim prognosis. Open surgical bypass is associated
with high morbidity, whereas endoscopic duodenal stenting appears to provide better palliation. Methods: We reviewed the medical
records of patients with gastric outlet obstruction secondary to pancreatic carcinoma who were admitted to our clinic between
1 October 1988, and 30 September 1998. The data included stage of disease, American Society of Anesthesiologists (ASA) class,
surgical interventions, complications, and survival. Results: A total of 250 patients with pancreatic cancer were identified.
Twenty-five of them (10%) had gastric outlet obstruction. Of these 25, 17 were treated with gastrojejunostomy, six had duodenal
stenting (Wallstent), and two were resectable. There was no significant difference between the gastrojejunostomy group and
the duodenal stenting group in ASA class or stage of disease. For the gastrojejunostomy group, median survival was 64 days
(range, 15-167) and postoperative stay in hospital was 15 days (range, 8-39). For the duodenal stenting group, median survival
was 110.5 days (range, 42-212) and postoperative stay was 4 days (range, 2-6). Ten patients (58.8%) in the gastrojejunostomy
group had delayed gastric emptying. All of the patients in the duodenal stenting group were able to tolerate a soft diet the
day after stent placement. Thirty-day mortality in the gastrojejunostomy group was 17.64%; in the duodenal stenting group,
it was 0. Conclusion: In pancreatic carcinoma patients with gastric outlet obstruction, duodenal stenting results in an earlier
discharge from hospital and possibly improved survival. 相似文献
738.
Kasia Bail RN BN GCHE PhD Diane Gibson BA PhD DBA FASSA Alicia Hind RN MGer Karen Strickland RN PhD Catherine Paterson PhD MSc BA PGCert LTA FHEA RN Eamon Merrick RN PhD Jo Gibson RN PhD Maria Kozlovskaia PhD Amy O’Dea BTh Bridget Smith RN PhD Bernice Redley RN PhD 《Journal of clinical nursing》2023,32(1-2):174-190
739.
Jared Stephenson Kent Chapman Soma Mohammed Diane Zebeljan Monica Ahuja Dea Donikian Leonardo Pasalic Penelope Motum Danny Hsu Timothy Brighton Emmanuel J. Favaloro 《International journal of laboratory hematology》2023,45(4):562-570