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排序方式: 共有813条查询结果,搜索用时 15 毫秒
51.
Biocompatibility and charge injection property of iridium film formed by ion beam assisted deposition 总被引:3,自引:0,他引:3
Iridium thin film formed by electron-beam evaporation with simultaneous bombardment of Ar ion beam was evaluated for a stimulating neural electrode. The electrochemical behavior of as-deposited Ir film on Ni-Ti sample was almost identical to bulk Ir by producing much higher open-circuit corrosion potential and much lower anodic current density than the uncoated Ni-Ti in both 1N sulfuric acid and saline solution. The charge injection capability of Ir film was compared with that of Pt electrode currently used mostly as a stimulating neural electrode. The charge density of Pt was small and unchanged with increasing number of activating cycles in 0.1M H(2)SO(4), whilst the Ir film continuously produced increases in charge density. The charge injection density of Ir film in physiological solution was higher for the more activated sample under the identical stimulating condition. Attachment and proliferation with PC12 cells on Ir-coated CP Ti without applying electrical stimulation was similar to the polished CP Ti. A network of neurons and extending axons were formed on Ir film. 相似文献
52.
McGuirt WF Whang C Moreland W 《Archives of otolaryngology--head & neck surgery》2002,128(11):1279-1281
OBJECTIVES: To describe our experience with primary and secondary Sj?gren syndrome (SS) in the pediatric population and to evaluate the effectiveness of parotid gland biopsy in the diagnosis of pediatric SS. DESIGN: Case series review of 6 pediatric patients evaluated during a 4-year period with varied head and neck manifestations of SS. SETTING: Tertiary care children's hospital. PATIENTS: Six children (4 boys and 2 girls) ranging in age from 6 to 12 years, who were diagnosed as having primary or secondary SS. INTERVENTION: Six minor salivary gland and 4 parotid gland biopsies for pathologic examination. MAIN OUTCOME MEASURES: Pathologic examination of salivary tissue consistent with SS. RESULTS: All 6 patients underwent minor salivary gland biopsy, 2 (33%) were consistent with SS, while the remaining 4 (67%) were nondiagnostic. The 4 patients with nondiagnostic minor salivary gland biopsy results went on to have parotid biopsies, of which all 4 had histologic findings consistent with SS. No complications were encountered. CONCLUSION: Parotid gland biopsy is an effective and safe means of obtaining salivary gland tissue for histologic evaluation of SS in the pediatric population. 相似文献
53.
Intravenous immunoglobulin (IVIG) has been used as an immunomodulatory treatment for several immune-mediated diseases. Early effects of high-dose IVIG treatment on biochemical profiles including lipids and proteins were evaluated in patients with Kawasaki disease (KD). Twelve children with KD (9 boys) were treated with IVIG at 2 g/kg over a period of 12 h. Serial sera samples were collected from the patients four times: before IVIG treatment and 2 h, 24 h and 7 d after IVIG treatment. The samples were frozen at -20°C before biochemical analysis. A significant decrease in albumin concentration was found 2 h and 24 h after IVIG treatment, but this recovered to the pretreatment level after 7 d. Total cholesterol and triglyceride increased slightly after 7 d. A significant decrease in HDL-cholesterol and C-reactive protein was seen 2 h and 24 h after IVIG treatment.
Conclusion : High-dose IVIG affects immediate changes in protein profiles and HDL-cholesterol in KD. Changes in HDL-cholesterol induced by IVIG may be the result of changes in systemic protein metabolism. 相似文献
Conclusion : High-dose IVIG affects immediate changes in protein profiles and HDL-cholesterol in KD. Changes in HDL-cholesterol induced by IVIG may be the result of changes in systemic protein metabolism. 相似文献
54.
Risk factors for arthralgias or myalgias associated with quinupristin-dalfopristin therapy 总被引:1,自引:0,他引:1
STUDY OBJECTIVE: To evaluate risk factors for the development of arthralgias or myalgias associated with quinupristin-dalfopristin. DESIGN: Retrospective chart review and case-control analysis. SETTING: An 850-bed tertiary care medical center. PATIENTS: All adult and pediatric patients who had received quinupristin-dalfopristin through either a compassionate-use protocol (February 1996-October 1999) or in the year after quinupristin-dalfopristin was added to the hospital formulary (November 1999-October 2000) were included in this study. Case patients were those who developed arthralgias or myalgias while receiving quinupristin-dalfopristin therapy; control patients were those who received quinupristin-dalfopristin but did not develop arthralgias or myalgias. INTERVENTION: Medical records, pharmacy dispensing information, and microbiology data were reviewed by a physician and a pharmacist, both of whom specialized in infectious diseases. Presence or absence of arthralgias or myalgias was the primary outcome assessed. MEASUREMENTS AND MAIN RESULTS: Quinupristin-dalfopristin was administered to 68 patients during the period defined by the study. Arthralgias and myalgias could not be assessed in 18 of the 68 patients because they were sedated and paralyzed, or they were young children who could not communicate the presence of pain. Univariate analysis demonstrated that significant risk factors for arthralgias or myalgias associated with quinupristin-dalfopristin were female sex, chronic liver disease, receipt of liver transplant, elevated bilirubin level at baseline, major surgery, and receipt of either mycophenolate or cyclosporine. Multivariate analysis demonstrated a strong association with chronic liver disease, receipt of liver transplant, elevated bilirubin level at baseline, and receipt of either cyclosporine or mycophenolate. Of 50 evaluable patients receiving quinupristin-dalfopristin, 25 had pain that may have been associated with this antimicrobial agent. CONCLUSION: The mechanism for development of arthralgias or myalgias associated with quinupristin-dalfopristin remains unknown, but these adverse events are more likely to occur in patients with chronic liver disease and those who have received a liver transplant or are receiving cyclosporine or mycophenolate. 相似文献
55.
Bhandari M Whang W Kuo JC Devereaux PJ Sprague S Tornetta P 《Clinical orthopaedics and related research》2003,(413):63-69
The risk of concluding that the results of a particular study are true, when, in fact, they really are attributable to chance (or random sampling error) is underappreciated by investigators. This erroneous false-positive conclusion is designated as a Type I or alpha error. The extent to which randomized trials in surgery risk Type I errors is unclear. The current authors hand-searched four orthopaedic journals, six general surgery journals, and five medical journals to identify recently published randomized trials (within the past 2 years). Information on outcomes and statistical adjustment for multiple outcomes was recorded for each study. The risk of a Type I error was calculated for each study that did not explicitly state a primary outcome measure for the main statistical comparison. One hundred fifty-nine studies met the inclusion criteria for the study: 60 studies from orthopaedic journals, 49 studies from nonorthopaedic surgical journals, and 50 studies from medical journals. Of the trials that did not state a primary outcome measure, the risk of Type I errors (false-positive results) in orthopaedic and nonorthopaedic surgery journals (mean 37.3% +/- 13.3% and 37.6% +/- 10.5%, respectively) were significantly greater than medical journals (10.1% +/- 1.9%). In the current review of randomized trials in surgery and medicine, the following is reported: (1) reporting of primary outcomes in trials was inadequate; (2) one in three trials in surgery and one in 10 trials in medicine risked false-positive results; and (3) few trials in surgery and medicine considered adjustment for multiple comparisons. 相似文献
56.
Acute cholecystitis at T2-weighted and manganese-enhanced T1-weighted MR cholangiography: preliminary study 总被引:4,自引:0,他引:4
Twelve patients with symptoms of acute cholecystitis underwent heavily T2-weighted and mangafodipir trisodium-enhanced T1-weighted magnetic resonance (MR) cholangiography and cholescintigraphy before they underwent cholecystectomy. On T2-weighted MR cholangiographic images, morphologic evidence of outflow obstruction of the gallbladder was definitive in seven patients, equivocal in one, and absent in four. In all 12 patients, biliary dynamics depicted at manganese-enhanced T1-weighted MR cholangiography agreed completely with those depicted at hepatobiliary scintigraphy. T2-weighted MR cholangiography combined with manganese-enhanced T1-weighted MR cholangiography provides not only morphologic information but also functional information about the biliary system. 相似文献
57.
Whang EE Perez A Ito H Mello MM Ashley SW Zinner MJ 《Journal of the American College of Surgeons》2003,197(4):624-630
BACKGROUND: New Accreditation Council for Graduate Medical Education (ACGME) requirements on resident duty hours are scheduled to undergo nationwide implementation in July 2003. General surgery residents, because of their long duty hours, are likely to be among those most affected by changes imposed to comply with the ACGME requirements. There are few contemporary data on their attitudes toward work hours reform. STUDY DESIGN: The study entailed a region-wide survey of residents enrolled in general surgery residencies in New England to characterize the perceptions and desires of surgical residents on the issue of work hours reform. RESULTS: Respondents reported working a mean of 105 +/- 0.7 hours per week, considerably more than the 80-hour limit stipulated by the ACGME. Of the respondents, 81% reported that sleep deprivation had negatively affected their work. A strong majority of respondents believe that work hours reform would improve their quality of life but less than one half expect it to have a positive impact on patient care. A greater percentage of senior residents than junior residents (p < 0.05) have negative perceptions of work hour limitations, particularly with respect to consequences for patient care. Other findings suggest that residents who have actually experienced work hour restrictions are less positive about such restrictions than these residents who had not yet experienced them. CONCLUSIONS: Changes imposed by residency programs to comply with work hour requirements might have detrimental effects on senior residents and patient care. The impact of such changes should be carefully monitored as the ACGME requirements are implemented. 相似文献
58.
Indications for early postoperative intraperitoneal chemotherapy of advanced gastric cancer: results of a prospective randomized trial 总被引:23,自引:0,他引:23
Previous analysis of this prospective randomized trial and meta-analysis of published randomized trials of adjuvant intraperitoneal
chemotherapy demonstrated improved survival in patients with advanced gastric cancer. Simple criteria applicable at the time
of surgery for patient selection were sought in this analysis. From 1990 to 1995 a series of 248 patients with biopsy-proven
gastric cancer were randomized intraoperatively to receive early postoperative intraperitoneal mitomycin C and 5-fluorouracil
(125 patients) versus surgery only (123 patients). Gastric resection plus early postoperative intraperitoneal chemotherapy
showed improved overall survival compared to surgery only (54% and 38%, respectively; p= 0.0278). There were statistically significant differences in patients with stage III (57% and 23%, respectively; p= 0.0024) and in those with stage IV (28% and 5%, respectively; p= 0.0098) gastric cancer. The improvement in survival rate was statistically significant for the subgroup of patients with
gross serosal invasion (52% and 25%, respectively; p= 0.0004) and patients with lymph node metastasis (46% and 22%, respectively; p= 0.0027). The surgeons' impression about lymph node status was unreliable, but assessment of serosal invasion was accurate
in 80% of cases. Gross serosal invasion with or without frozen section evaluation of lymph nodes can be used as the major
selection criteria for early postoperative intraperitoneal chemotherapy of advanced gastric cancer. 相似文献
59.
Georgopoulos AP Whang K Georgopoulos MA Tagaris GA Amirikian B Richter W Kim SG Uğurbil K 《Journal of cognitive neuroscience》2001,13(1):72-89
We studied the brain activation patterns in two visual image processing tasks requiring judgements on object construction (FIT task) or object sameness (SAME task). Eight right-handed healthy human subjects (four women and four men) performed the two tasks in a randomized block design while 5-mm, multislice functional images of the whole brain were acquired using a 4-tesla system using blood oxygenation dependent (BOLD) activation. Pairs of objects were picked randomly from a set of 25 oriented fragments of a square and presented to the subjects approximately every 5 sec. In the FIT task, subjects had to indicate, by pushing one of two buttons, whether the two fragments could match to form a perfect square, whereas in the SAME task they had to decide whether they were the same or not. In a control task, preceding and following each of the two tasks above, a single square was presented at the same rate and subjects pushed any of the two keys at random. Functional activation maps were constructed based on a combination of conservative criteria. The areas with activated pixels were identified using Talairach coordinates and anatomical landmarks, and the number of activated pixels was determined for each area. Altogether, 379 pixels were activated. The counts of activated pixels did not differ significantly between the two tasks or between the two genders. However, there were significantly more activated pixels in the left (n = 218) than the right side of the brain (n = 161). Of the 379 activated pixels, 371 were located in the cerebral cortex. The Talairach coordinates of these pixels were analyzed with respect to their overall distribution in the two tasks. These distributions differed significantly between the two tasks. With respect to individual dimensions, the two tasks differed significantly in the anterior--posterior and superior--inferior distributions but not in the left--right (including mediolateral, within the left or right side) distribution. Specifically, the FIT distribution was, overall, more anterior and inferior than that of the SAME task. A detailed analysis of the counts and spatial distributions of activated pixels was carried out for 15 brain areas (all in the cerebral cortex) in which a consistent activation (in > or = 3 subjects) was observed (n = 323 activated pixels). We found the following. Except for the inferior temporal gyrus, which was activated exclusively in the FIT task, all other areas showed activation in both tasks but to different extents. Based on the extent of activation, areas fell within two distinct groups (FIT or SAME) depending on which pixel count (i.e., FIT or SAME) was greater. The FIT group consisted of the following areas, in decreasing FIT/SAME order (brackets indicate ties): GTi, GTs, GC, GFi, GFd, [GTm, GF], GO. The SAME group consisted of the following areas, in decreasing SAME/FIT order : GOi, LPs, Sca, GPrC, GPoC, [GFs, GFm]. These results indicate that there are distributed, graded, and partially overlapping patterns of activation during performance of the two tasks. We attribute these overlapping patterns of activation to the engagement of partially shared processes. Activated pixels clustered to three types of clusters : FIT-only (111 pixels), SAME-only (97 pixels), and FIT + SAME (115 pixels). Pixels contained in FIT-only and SAME-only clusters were distributed approximately equally between the left and right hemispheres, whereas pixels in the SAME + FIT clusters were located mostly in the left hemisphere. With respect to gender, the left-right distribution of activated pixels was very similar in women and men for the SAME-only and FIT + SAME clusters but differed for the FIT-only case in which there was a prominent left side preponderance for women, in contrast to a right side preponderance for men. We conclude that (a) cortical mechanisms common for processing visual object construction and discrimination involve mostly the left hemisphere, (b) cortical mechanisms specific for these tasks engage both hemispheres, and (c) in object construction only, men engage predominantly the right hemisphere whereas women show a left-hemisphere preponderance. 相似文献
60.
Shin JW Lee SY Lee JS Whang KU Park YL Lee HK 《International journal of dermatology》2012,51(2):152-157
Background Prurigo pigmentosa (PP) is an inflammatory dermatosis characterized by recurrent pruritic erythematous papules, mainly located on the trunk. It was first described by Nagashima in 1971 in Japan. Since then, more than 300 cases have been reported in Japan, but reports from other parts of the world are quite rare. Materials and methods We studied clinical and histopathological data from six patients with PP diagnosed in our hospital and 43 patients (18 reports) who were diagnosed with PP in Korea between 1988 and 2008. Results The number of Korean patients reported in recent years is higher than the number of other non‐Japanese patients reported. Clinicopathological characteristics in Korean patients were not significantly different from those previously reported. Therapeutic results with minocycline were successful in our patients. Conclusions We suspect that PP is not uncommon in Korea, and the disease may be underestimated. Strict restriction of diet as well as known associated factors like wet condition are suggested as one of the important factors contributing to the occurrence of PP in Korea. 相似文献