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Anne Spaar Martin Frey Alexander Turk Werner Karrer Milo A Puhan 《BMC medical research methodology》2009,9(1):14-8
Background
The feasibility of randomized trials often depends on successful patient recruitment. Although numerous recruitment barriers have been identified it is unclear which of them complicate recruitment most. Also, most surveys have focused on the patients' perspective of recruitment barriers whereas the perspective of recruiting physicians has received less attention. Therefore, our aim was to conduct a postal survey among recruiting physicians of a multi-center trial to weigh barriers according to their impact on recruitment. 相似文献105.
Macan J Vucemilović A Turk R Medugorac B Milković-Kraus S Gomzi M Poljak I 《Occupational medicine (Oxford, England)》2000,50(1):22-24
Histamine poisoning due to inhalation and skin contact with fish products is rarely described in the literature. This study presents a case of occupational histamine poisoning by spoiled fish flour via inhalation, skin and eye contact. Shipments of fish flour transported in black or blue bags, depending on the source, were handled by 20 harbour workers. Ten workers handling blue bags developed allergy-like skin, eye, gastrointestinal, respiratory and cardiac symptoms within 30 min. Workers handling black bags were symptom-free, except for minimal eye irritation. After consultation with the Poison Control Centre histamine poisoning was suspected. The histamine content, as determined by thin-layer chromatography, was 10-fold higher in samples from the blue than from the black bags (510 mg/100 g flour compared with 50 mg/100 g flour, respectively). Part of the shipment was labelled as hazardous for human health with permission for further usage only under specific personal protective measures. It is suggested that the highest permissible levels of histamine in fish flour and similar products should be set and legally adopted. 相似文献
106.
DC Wilson MJ Cunningham MMcC Reid SS Johnston TF Fannin 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(1):84-85
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis. 相似文献
107.
Uitti RJ Tsuboi Y Pooley RA Putzke JD Turk MF Wszolek ZK Witte RJ Wharen RE 《Neurosurgery》2002,51(6):1423-28; discussion 1428-31
OBJECTIVE: To determine whether cranial magnetic resonance imaging (MRI) is associated with deep brain stimulation (DBS) lead displacement or program interference. METHODS: In vitro and in vivo studies were performed with the Itrel II implantable pulse generator (IPG) (Model 7424; Medtronic, Minneapolis, MN), Medtronic 3387 and 3389 leads, and a 1.5-T GE Horizon LX scanner (General Electric, Milwaukee, WI). In the in vivo study, two MRI volumetric data sets were compared for each of five patients undergoing staged, bilateral, DBS electrode placement in the thalamic or subthalamic nucleus. The data sets were acquired shortly after the initial implantation and during stereotactic planning for the second implantation (1-8 mo between acquisitions). An additional thalamotomy-treated patient was included as a control patient. Volumetric data were analyzed in a blinded manner, using AnalyzeAVW 3.0 software (Biomedical Imaging Resource, Mayo Clinic, Rochester, MN), to determine lead movement. In the in vitro study, the IPG and leads were positioned in the magnetic field in various configurations and were systematically assessed for movement. RESULTS: In vivo, the majority of measured deviations (88%) were within the standard error of measurement (1.4 mm). The maximal measured deviation was 3 mm (2% occurrence). Excellent tremor control with stimulation was demonstrated, which did not change after MRI. In vitro, the DBS leads demonstrated no deflection when introduced into the magnetic field. Similarly, no changes in IPG battery strength, lead impedance, or program settings were observed. CONCLUSION: MRI was not associated with significant DBS electrode movement or changes in clinical responses. Other IPG models and components and MRI scanners should be evaluated, to develop specific guidelines for MRI among individuals with implanted DBS systems. 相似文献
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109.
Albala DM Fulmer BR Turk TM Koleski F Andriole G Davis BE Eure GR Kabalin JN Lingeman JE Nuzzarello J Sundaram C 《Journal of endourology / Endourological Society》2002,16(1):57-61
BACKGROUND AND PURPOSE: Transurethral microwave thermotherapy (TUMT) is an effective therapy for symptomatic benign prostatic hyperplasia (BPH), but the trade-off between the magnitude of clinical improvement and side effects and patient tolerance has limited its appeal to patients and urologists. This study, using the TherMatrx TMx-2000, a TUMT device that directly heats the transition zone to greater than 50 degrees C, has been focused on resolving these issues and developing a truly office-based therapy that is well tolerated with a benign post-treatment course. PATIENTS AND METHODS: This study was multi-institutional and designed as a blinded, randomized, and sham-controlled trial. A series of 200 patients with an AUA Symptom Index (AUASI) of >12, a peak flow rate of <12 mL/sec, and cystoscopic evidence of BPH were randomized 2:1 (active to sham) and treated in seven physician offices under a Food and Drug Administration-supervised and audited premarket approval protocol. No intravenous sedation was used in any patient. Follow-up for the sham-treatment group was 3 months, at which time, patients could cross over to an active treatment. A total of 119 patients have completed 1-year follow-up. RESULTS: The active and sham groups were statistically identical at baseline. The 1-hour total treatment was extremely well tolerated using urethral lidocaine and oral medications; not a single prostate block or parental dose of medication was required. The active-treatment group demonstrated a statistically significant reduction (p < 0.05) in AUASI at 3 months compared with sham treatment, with an AUASI decrease from 22.4 to 12.4 (n = 124) for active v 22.9 to 17 for sham (n = 62). For the 119 patients in the active arm who have reached 12 months, the AUASI has fallen to 10.6 points (47.1% decrease), and the peak flow rate has increased 5.0 mL/sec (58.1%). Postprocedure catheterization was typically 2 or 3 days, and the 16.8% of patients who failed their first voiding trial all voided within 1 week. No major adverse events such as stricture, rectal findings, or ejaculatory changes have been reported. CONCLUSIONS: This study demonstrates that the TherMatrx TMx-2000 TUMT effectively treats symptomatic BPH in the physician office with minimal morbidity. 相似文献
110.
Antiretroviral activity and cytotoxicity of novel zidovudine (AZT) derivatives and the relation to their chemical structure 总被引:1,自引:0,他引:1
Turk G Moroni G Pampuro S Briñón MC Salomón H 《International journal of antimicrobial agents》2002,20(4):282-288
Zidovudine (AZT) was the first nucleoside analogue licensed for the treatment of HIV infection. Efforts have continuously been made to improve the therapeutic characteristics of this drug, most of them focussed on prodrugs design. Here we describe the anti-HIV-1 activity and cytotoxicity of six novel AZT derivatives namely 3'-azido-3'-deoxy-5'-O-oxalyl-N-valinethymidine, 3'-azido-3'-deoxy-5'-O-oxalyl-N-leucinethymidine, 3'-azido-3'-deoxy-5'-O-oxalyl-N-isoleucinethymidine, 3'-azido-3'-deoxy-5'-O-oxalyl-N-phenylalaninethymidine, 3'-azido-3'-deoxy-5'-O-oxalylthymidine acid, 3'-azido-3'-deoxy-5'-O-isonicotinoylthymidine and 5-chloro-6-hydroxy-5,6-dihydro-3'-azido-3'-deoxythymidine which were perfectly characterized. AZT-Val, AZT-Leu, AZT-iLeu, AZT-Phen, AZT-Ac and AZT-Iso have shown a similar or higher selectivity index than that of AZT itself, in one or both of the different cell cultures used (PBMC and MT2). However, AZT-ClOH showed no anti-HIV activity. These results suggest that using amino acids in the design of AZT derivatives improves AZT activity. 相似文献