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71.
Thorsten G Lehmann Tom Luedde Robert F Schwabe Hartwig Bunzendahl R Jude Samulski John J Lemasters David A Brenner 《Liver transplantation》2006,12(4):550-559
Transplantation of reduced-size livers may lead to a hypermetabolic state and increased production of oxygen radicals. Since oxygen radicals may cause liver injury and impair liver regeneration, we tested the hypothesis that overexpression of superoxide dismutase (SOD) in reduced-size livers (RSL) would accelerate regeneration and reduce injury in a rat model of transplantation of RSL. Donor rats were infected with adenoviruses either expressing SOD1 (Ad.SOD1) or beta-galactosidase (Ad.lacZ). Livers were harvested 72 hours later, reduced to 45% of weight, and transplanted. After transplantation, hepatic SOD activity, graft survival, histopathology, AST/ALT release, and bilirubin were examined. Regeneration was evaluated by BrdU-staining, graft weight, and expression of cyclin D1 and p21. In Ad.SOD1-treated livergrafts, SOD activity increased three-fold compared to controls. Survival was dramatically increased in recipients of Ad.SOD1-RSL (100% vs. 20% in Ad.lacZ-RSL), and peak levels of AST/ALT and bilirubin levels were reduced by 75% and 87.5%, respectively (P < 0.001). In histological sections, hepatocyte necrosis decreased from 24% after Ad.lacZ-treatment to 6% after Ad.SOD1-treatment (P <0.001). Regeneration was also accelerated after Ad.SOD1-treatment as demonstrated by an increase of BrdU-stained cells 24 hours after reperfusion and increased liver weight after 1 week. In conclusion, overexpression of SOD1 in RSL prevents primary non-function of reduced-size liver grafts and accelerates liver regeneration. 相似文献
72.
Cyrus Behzadi Murat Karul Frank Oliver Henes Azien Laqmani Philipp Catala-Lehnen Wolfgang Lehmann Hans-Dieter Nagel Gerhard Adam Marc Regier 《World journal of radiology》2015,7(1):22-27
AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma. 相似文献
73.
Scheunemann D Lehmann W Briem D Stork A Windolf J Rueger JM Linhart W 《Der Unfallchirurg》2005,108(8):638-644
ZusammenfassungHintergrund Die MRT stellt ein sensitives, nicht strahlenbelastendes bildgebendes Verfahren dar und bietet sich daher für die Diagnostik kindlicher Wirbelsäulenverletzungen an. Als ein indirektes Verletzungszeichen lässt sich hierbei u. U. ein sog. bone bruise nachweisen, ohne dass weitere Verletzungen sichtbar werden. Ziel der vorliegenden Arbeit war es, die klinische Bedeutung dieser Diagnose bei kindlichen Wirbelsäulenverletzungen zu untersuchen.Patienten und Methoden Zwischen 1998 und 2003 wurden in unserer Klinik insgesamt 66 Kinder mit Wirbelsäulenverletzungen konservativ behandelt. 34 dieser Kinder erhielten während der Primärdiagnostik eine MRT. Im Rahmen einer retrospektiven Studie wurden 20 Kinder, bei welchen die Diagnose einer Wirbelkörperverletzung vorwiegend durch den Nachweis eines bone bruise im initialen MRT geführt worden war, sowohl klinisch als auch mittels MRT nachuntersucht.Ergebnisse Alle 20 Kinder gaben bei der Nachuntersuchung subjektiv weitgehende Beschwerdefreiheit an. Bei der objektiven Untersuchung fanden sich keine klinischen Auffälligkeiten. Bei keinem der Kinder war im Rahmen der Nachuntersuchung MR-tomographisch eine Persistenz des bone bruise feststellbar. Eine sekundäre Sinterung der betroffenen Wirbelkörper war in keinem Fall aufgetreten.Schlussfolgerung Kindliche Wirbelsäulenverletzungen, die mit einem mittels MRT nachgewiesenen bone bruise ohne weitere bildmorphologische knöcherne oder diskoligamentäre Läsionen einhergehen, sind in der Regel als prognostisch günstig einzustufen. Bei entsprechender Therapie, die in einer kurzfristigen, schmerzadaptierten Bettruhe und einer anschließenden frühfunktionellen Behandlung besteht, wurden bei unseren Patienten keine sekundären Sinterungen beobachtet.* Beide Autoren haben gleichen Anteil an dieser Arbeit und teilen sich die Erstautorenschaft. 相似文献
74.
Siemer S Lehmann J Loch A Becker F Stein U Schneider G Ziegler M Stöckle M 《The Journal of urology》2005,173(1):33-37
PURPOSE:: Recent studies of rare cases of pT3a renal cell carcinoma extending directly into the adrenal gland showed worse survival than in other pT3a cases and recategorization as stage pT4 was suggested. We assessed the prognostic validity of a stage pT3a diagnosis based on perirenal fat infiltration. MATERIALS AND METHODS:: The records of 1,794 patients with renal cell carcinoma who underwent surgical resection between 1975 and 2000 at our institution were analyzed retrospectively. Focusing on pT3a tumors, as defined by perirenal fat infiltration, numerous clinical and histopathological parameters were investigated by univariate and multivariate statistical methods with cancer specific survival as the primary end point. RESULTS:: We identified 237 of 1,794 patients with perirenal fat infiltration, classified as having pT3a disease. In patients with pT3a tumors tumor size was a significant parameter predicting survival. The most significant cutoff value for tumor size in pT3a disease was 7 cm. Patients with distant metastasis had a worse prognosis independent of T classification. Therefore, to assess the prognostic value of the current T classification in regard to T3a tumors we excluded patients with tumor stage cM+ for further subgroup analysis. Survival comparison of pT1 pNall, cM0 (744 of 1,794 cases) and pT3a pNall, cM0 7 cm or less (100 of 237) as well as pT2 pNall, cM0 (265 of 1,794) and pT3a pNall, cM0 greater than 7 cm (93 of 237) yielded similar results. After splitting pT3a into a modified T1/T2 classification a significant difference in 5-year survival analysis for a modified T1/T2 stage was found (pT1 plus pT3a less than 7 cm 90% vs pT2 plus pT3a greater than 7 cm 73%, p <0.001). Subsequently multivariate analysis in all 1,794 patients showed that modified T stage was an independent significant predictor of cancer specific survival. CONCLUSIONS:: We suggest revising the current pT3a classification based on perirenal fat infiltration but rendering a modified pT1/pT2 classification, which resolves pT3a cases without the loss of prognostic validity. Perirenal fat infiltration should not be used to assign T category. Tumors directly infiltrating the adrenal gland should be reclassified as T4. 相似文献
75.
Effectivity of laser-induced thermotherapy: in vivo comparison of arterial microembolization and complete hepatic inflow occlusion 总被引:3,自引:0,他引:3
Ritz JP Lehmann K Isbert C Roggan A Germer CT Buhr HJ 《Lasers in surgery and medicine》2005,36(3):238-244
BACKGROUND AND OBJECTIVES: Laser-induced thermotherapy (LITT) is a promising method for local treatment of liver metastases. The aim of this study was to compare the effect of LITT on lesion size when combined with hepatic arterial microembolization or complete hepatic blood flow occlusion. STUDY DESIGN/MATERIALS AND METHODS: In a porcine liver model, LITT (30 W 15 minutes) was performed with either normal (n = 12), partially interrupted (arterial microembolization via a hepatic artery catheter n = 12) or completely interrupted hepatic perfusion (Pringle's maneuver, n = 12). LITT lesions were macro- and microscopically assessed after liver dissection. RESULTS: Hepatic inflow occlusion led to a fourfold increase in lesion volume after arterial microembolization and a ninefold increase after complete interruption (6.3. cm3 vs. 27.1 cm3 vs. 58.8 cm3, P < 0.01). CONCLUSIONS: Interrupting hepatic perfusion significantly increases lesion volumes in LITT. This beneficial effect can also be achieved in the percutaneous application mode by LITT combined with arterial microembolization via a hepatic artery catheter. 相似文献
76.
The potential clinical utility of drug interactions between morphine and the cholecystokinin antagonist proglumide was examined in 80 postoperative patients suffering from moderate to severe pain. Four groups of ASA I-III patients (mean age 51 years, mean weight 72 kg) recovering from major abdominal or gynecological surgery (mean duration of surgery 141 minutes) performed under balanced anesthesia (midazolam, droperidol, fentanyl, N2O, enflurane) were randomly assigned to self-administer morphine-proglumide mixtures on the first postoperative day (ODAC; morphine demand dose 3 mg; infusion rate 0.36 mg/hr; lockout time 2 minutes; hourly maximum dose 15 mg/hr; proglumide doses per demand 0, 50 micrograms, 100 micrograms, or 50 mg). Morphine consumption, actual as well as retrospective pain scores (0-5) and side effects were evaluated. Mean duration of patient-controlled analgesia (PCA) in the subgroups was 17-19 hours, during which time 24.6 +/- 9.5 to 28.0 +/- 3.4 micrograms morphine.kg-1.hr-1 was given. There were no statistically significant differences between the groups either for drug consumption, pain scores, or side effects. It is therefore concluded that proglumide does not potentiate morphine analgesia in a clinical (postoperative) setting. 相似文献
77.
Kasaj A Meister J Lehmann K Stratul SI Schlee M Stein JM Willershausen B Schmidt M 《Journal of periodontal research》2012,47(4):479-487
Kasaj A, Meister J, Lehmann K, Stratul SI, Schlee M, Stein JM, Willershausen B, Schmidt M. The influence of enamel matrix derivative on the angiogenic activity of primary endothelial cells. J Periodont Res 2012; 47: 479–487. © 2011 John Wiley & Sons A/S Background and Objective: Angiogenesis plays a crucial role in early wound healing and tissue regeneration. Although enamel matrix derivative (EMD) has demonstrated the potential to stimulate periodontal regeneration, the biological effects of EMD on angiogenesis and underlying mechanisms have not been fully elucidated. The aim of the present study was to examine the angiogenic effects of EMD in vitro. Material and Methods: Human umbilical vein endothelial cells (HUVECs) were used to assess the effect of EMD on proliferation, survival, adhesion and migration. The effect of EMD on HUVEC angiogenesis was assessed by a three‐dimensional sprouting assay. In order to understand the signalling mechanism of altered cell proliferation of HUVECs caused by EMD, the phosphorylation status of ERK1/2 and of the serine/threonine protein kinase Akt was analysed by western blot using phospho‐specific antibodies. Results: The proliferation of HUVECs was stimulated by 50 μg/mL EMD, whereas higher concentrations (≥ 100 μg/mL) resulted in an increased apoptotic rate. The mitogenic response to EMD was associated with the activation of ERK1/2. Enamel matrix derivative did not affect cell adhesion, but all concentrations of EMD tested (0.1–250 μg/mL) promoted migration of HUVECs. Furthermore, EMD induced capillary‐like sprout formation from HUVEC spheroids in a dose‐dependent manner. Conclusion: Our data indicate that EMD acts as a proangiogenic factor in vitro and, as such, might contribute to periodontal tissue regeneration by stimulation of vessel formation during wound healing. 相似文献
78.
PURPOSE: To evaluate the efficacy of AcrySof SN60WF aspheric intraocular lens (IOL) in decreasing spherical aberration and total higher order aberrations (HOAs) after cataract surgery compared to the spherical SN60AT lens. METHODS: Wavefront analysis was conducted on 28 eyes of 28 patients that underwent un-complicated phacoemulsification with implantation of either SN60WF (15 eyes) or SN60AT lenses (13 eyes). Eyes with a history of uveitis, retinal diseases, and previous surgery were excluded. RESULTS: SN60WF eyes had less mean absolute spherical aberration than SN60AT eyes both at 4 mm (0.04+/-0.03 vs 0.11+/-0.03 RMS, p<0.0001) and 6 mm pupils (0.09+/-0.04 vs 0.43+/-0.12 RMS, p<0.0001). Mean total HOAs was lower in the SN60WF group at 6 mm pupils (0.44+/-0.14 vs 0.56+/-0.13 RMS, p=0.0274), while no difference was seen at 4 mm pupils (0.20+/-0.10 vs 0.25+/-0.08 RMS, p=0.160). There were no clinically significant differences between the SN60WF and SN60AT IOLs both at 4 and 6 mm pupils in terms of coma (0.16+/-0.07 vs 0.18+/-0.09 RMS, p=0.514 and 0.25+/-0.12 vs 0.23+/-0.12 RMS, p=0.664) and trefoil (0.14+/-0.09 vs 0.10+/-0.05 RMS, p=0.167 and 0.28+/-0.12 vs 0.23+/-0.07 RMS, p=0.199). There were no differences be-tween groups in mean age, axial length, postoperative spherical equivalent, IOL power, or corneal curvature. CONCLUSIONS: An aspheric posterior optic IOL design with thinner center effectively reduces the positive ocular spherical aberration observed in the pseudophakic and elderly eyes, especially at larger pupillary diameters (6 mm), with no notable increase in coma. However, reduction in total ocular HOAs was only significant at 6 mm pupils. 相似文献
79.
I. L. M. Larkin T. Baker P. A. Lorkin H. Lehmann A. J. Black R. G. Huntsman 《British journal of haematology》1968,14(2):233-238
S ummary A survey of 13 ,000 cord bloods in Great Britain yielded an electrophoretically abnormal variant of Haemoglobin F which resembled Haemoglobin F Texas. Haemoglobin F Texas might be either α2 γ2 5G1u→Lys or α2 γ2 6Glu→Lys . The first has been described and was named Haemoglobin F Texas I. The present variant has the same substitution in the sixth residue of the γ chain and is designated as Haenioglobin F Texas II. 相似文献
80.
Lupus erythematosus 总被引:2,自引:0,他引:2
G Goerz P Lehmann H C Schuppe H J Lakomek P Kind 《Zeitschrift für Hautkrankheiten》1990,65(3):226, 229-226, 234
Our paper summarizes the clinical and photobiological studies on lupus erythematosus (LE) performed at the Department of Dermatology, University of Düsseldorf, during the last 5 years. A total of 190 LE cases were examined and classified according to the various cutaneous forms of LE. Except for lupus erythematosus tumidus (LET), we found a female predominance in all other groups. Discoid lupus erythematosus (DLE) is the most common variant of cutaneous LE. Subacute cutaneous lupus erythematosus (SCLE), a less common type, is characterized by the presence of Ro-antibodies, although this marker does not correlate with the degree of photosensitivity. The rare LET is an extremely photosensitive form of LE, which clearly prefers the male sex. 相似文献