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Sir, I read with great interest the letter by Higgins and co-workers[1]. 相似文献
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S A al Rasheed M B Abdurrahman M M al Mugeiren I M al Fawaz 《Journal of tropical pediatrics》1991,37(3):127-130
A retrospective study was carried out on 40 children from Saudi Arabia with Henoch-Sch?nlein syndrome to delineate its clinical pattern. More than 50 per cent of the cases occurred in winter. There was no apparent causal relationship with B-haemolytic streptococcal infection. All patients had skin rash. Fifty-eight per cent had gastrointestinal manifestations, 58 per cent had joint manifestations and 38 per cent had renal manifestations. The main clinical features of Henoch-Sch?nlein syndrome in Saudi children are comparable to those reported elsewhere. 相似文献
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Characterization of clinical isolates of Klebsiella pneumoniae from 19 laboratories using the National Committee for Clinical Laboratory Standards extended-spectrum beta-lactamase detection methods 总被引:4,自引:0,他引:4 下载免费PDF全文
Steward CD Rasheed JK Hubert SK Biddle JW Raney PM Anderson GJ Williams PP Brittain KL Oliver A McGowan JE Tenover FC 《Journal of clinical microbiology》2001,39(8):2864-2872
Extended-spectrum beta-lactamases (ESBLs) are enzymes found in gram-negative bacilli that mediate resistance to extended-spectrum cephalosporins and aztreonam. In 1999, the National Committee for Clinical Laboratory Standards (NCCLS) published methods for screening and confirming the presence of ESBLs in Klebsiella pneumoniae, Klebsiella oxytoca, and Escherichia coli. To evaluate the confirmation protocol, we tested 139 isolates of K. pneumoniae that were sent to Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology) from 19 hospitals in 11 U.S. states. Each isolate met the NCCLS screening criteria for potential ESBL producers (ceftazidime [CAZ] or cefotaxime [CTX] MICs were > or =2 microg/ml for all isolates). Initially, 117 (84%) isolates demonstrated a clavulanic acid (CA) effect by disk diffusion (i.e., an increase in CAZ or CTX zone diameters of > or =5 mm in the presence of CA), and 114 (82%) demonstrated a CA effect by broth microdilution (reduction of CAZ or CTX MICs by > or =3 dilutions). For five isolates, a CA effect could not be determined initially by broth microdilution because of off-scale CAZ results. However, a CA effect was observed in two of these isolates by testing cefepime and cefepime plus CA. The cefoxitin MICs for 23 isolates that failed to show a CA effect by broth microdilution were > or =32 microg/ml, suggesting either the presence of an AmpC-type beta-lactamase or porin changes that could mask a CA effect. By isoelectric focusing (IEF), 7 of the 23 isolates contained a beta-lactamase with a pI of > or =8.3 suggestive of an AmpC-type beta-lactamase; 6 of the 7 isolates were shown by PCR to contain both ampC-type and bla(OXA) genes. The IEF profiles of the remaining 16 isolates showed a variety of beta-lactamase bands, all of which had pIs of < or =7.5. All 16 isolates were negative by PCR with multiple primer sets for ampC-type, bla(OXA), and bla(CTX-M) genes. In summary, 83.5% of the K. pneumoniae isolates that were identified initially as presumptive ESBL producers were positive for a CA effect, while 5.0% contained beta-lactamases that likely masked the CA effect. The remaining 11.5% of the isolates studied contained beta-lactamases that did not demonstrate a CA effect. An algorithm based on phenotypic analyses is suggested for evaluation of such isolates. 相似文献
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W B Baine J K Rasheed D C Mackel C A Bopp J G Wells A F Kaufmann 《Journal of clinical microbiology》1979,9(3):453-456
Hemolysis occurred around growth of the Legionnaires disease bacterium on supplemented Mueller-Hinton agar containing sterile defibrinated blood from each of five mammalian species. Hemolysis was most pronounced with guinea pig or rabbit blood, was less intense with horse or sheep blood, and was slight with blood from a human donor. Sterile filtrates of allantoic fluid from embryonated hen's eggs that had been infected with this organism displayed hemolytic activity in a radial hemolysis assay with guinea pig cells in agar. Growth of the Legionnaires disease bacterium on F-G agar with 5% hen's egg yolk was surrounded by a zone of clearing and more circumscribed zones of iridescence and increased opacity on and in the medium. Attempts to detect activity analogous to that of Escherichia coli heat-labile or heat-stable enterotoxin in allantoic fluid from infected eggs or in cultures of the Legionnaires disease bacterium were not successful. 相似文献
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Phase II trial of gefitinib in recurrent glioblastoma. 总被引:13,自引:0,他引:13
Jeremy N Rich David A Reardon Terry Peery Jeannette M Dowell Jennifer A Quinn Kara L Penne Carol J Wikstrand Lauren B Van Duyn Janet E Dancey Roger E McLendon James C Kao Timothy T Stenzel B K Ahmed Rasheed Sandra E Tourt-Uhlig James E Herndon James J Vredenburgh John H Sampson Allan H Friedman Darell D Bigner Henry S Friedman 《Journal of clinical oncology》2004,22(1):133-142
PURPOSE: To evaluate the efficacy and tolerability of gefitinib (ZD1839, Iressa; AstraZeneca, Wilmington, DE), a novel epidermal growth factor receptor tyrosine kinase inhibitor, in patients with recurrent glioblastoma. PATIENTS AND METHODS: This was an open-label, single-center phase II trial. Fifty-seven patients with first recurrence of a glioblastoma who were previously treated with surgical resection, radiation, and usually chemotherapy underwent an open biopsy or resection at evaluation for confirmation of tumor recurrence. Each patient initially received 500 mg of gefitinib orally once daily; dose escalation to 750 mg then 1,000 mg, if a patient received enzyme-inducing antiepileptic drugs or dexamethasone, was allowed within each patient. RESULTS: Although no objective tumor responses were seen among the 53 assessable patients, only 21% of patients (11 of 53 patients) had measurable disease at treatment initiation. Seventeen percent of patients (nine of 53 patients) underwent at least six 4-week cycles, and the 6-month event-free survival (EFS) was 13% (seven of 53 patients). The median EFS time was 8.1 weeks, and the median overall survival (OS) time from treatment initiation was 39.4 weeks. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea. Drug-related toxicities were more frequent at higher doses. Withdrawal caused by drug-related adverse events occurred in 6% of patients (three of 53 patients). Although the presence of diarrhea positively predicted favorable OS from treatment initiation, epidermal growth factor receptor expression did not correlate with either EFS or OS. CONCLUSION: Gefitinib is well tolerated and has activity in patients with recurrent glioblastoma. Further study of this agent at higher doses is warranted. 相似文献
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Dunne EF Fey PD Kludt P Reporter R Mostashari F Shillam P Wicklund J Miller C Holland B Stamey K Barrett TJ Rasheed JK Tenover FC Ribot EM Angulo FJ 《JAMA》2000,284(24):3151-3156
Context Ceftriaxone, an expanded-spectrum cephalosporin, is an antimicrobial agent commonly used to treat severe Salmonella infections, especially in children. Ceftriaxone-resistant Salmonella infections have recently been reported in the United States, but the extent of the problem is unknown. Objectives To summarize national surveillance data for ceftriaxone-resistant Salmonella infections in the United States and to describe mechanisms of resistance. Design and Setting Case series and laboratory evaluation of human isolates submitted to the Centers for Disease Control and Prevention from 17 state and community health departments participating in the National Antimicrobial Resistance Monitoring System (NARMS) for enteric bacteria between 1996 and 1998. Patients Patients with ceftriaxone-resistant Salmonella infections between 1996 and 1998 were interviewed and isolates with decreased ceftriaxone susceptibility were further characterized. Main Outcome Measures Exposures and illness outcomes, mechanisms of resistance. Results The prevalence of ceftriaxone-resistant Salmonella was 0.1% (1 of 1326) in 1996, 0.4% (5 of 1301) in 1997, and 0.5% (7 of 1466) in 1998. Ten (77%) of the 13 patients with ceftriaxone-resistant infections were aged 18 years or younger. The patients lived in 8 states (California, Colorado, Kansas, Massachusetts, Maryland, Minnesota, New York, and Oregon). Nine (82%) of 11 patients interviewed did not take antimicrobial agents and 10 (91%) did not travel outside the United States before illness onset. Twelve of the 15 Salmonella isolates with ceftriaxone minimum inhibitory concentrations of 16 µg/mL or higher were serotype Typhimurium but these isolates had different pulsed-field gel electrophoresis patterns. Thirteen of these 15 isolates collected between 1996 and 1998 were positive for a 631base pair polymerase chain reaction product obtained by using primers specific for the ampC gene of Citrobacter freundii. Conclusions Domestically acquired ceftriaxone-resistant Salmonella has emerged in the United States. Most ceftriaxone-resistant Salmonella isolates had similar AmpC plasmid-mediated resistance. 相似文献
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K S Asgeirsson T Rasheed S J McCulley R D Macmillan 《European journal of surgical oncology》2005,31(8):817-823
BACKGROUND: Breast-conserving surgery and radiotherapy is firmly established as a good and safe option for most women with early breast cancer. The important outcome measures of breast conservation are survival, local recurrence, cosmesis and patient satisfaction. Partial breast reconstructive techniques may improve cosmesis and patient satisfaction without compromising the oncological outcomes. METHODS: A search of the Medline and Pubmed databases of studies on breast conserving surgery where partial breast reconstructive techniques were employed. The keywords used were breast conserving surgery, oncoplastic breast surgery, partial breast reconstruction and reduction mammoplasty. The oncological and cosmetic outcomes of these studies were analysed. RESULTS: Studies on partial breast reconstructive techniques often lack oncological outcomes and long-term results are not available. On intermediate follow-up (up to 4.5 years) local recurrence rates vary from 0 to 1.8% per year. Cosmetic failure rates vary from 0 to 18%. To date, detailed studies are small and outcome measures vary. CONCLUSIONS: Breast surgeons should be aware of the range of surgical techniques that may enhance the aesthetic results of breast-conserving surgery as well as expand the indications for its use. There is a need for routine assessment of oncological and cosmetic outcomes and long-term results of partial breast reconstructive techniques in relation to these outcomes are awaited. 相似文献