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31.
Christian Foged Christer Halldin Christian Loc’h Bernard Mazière Stefan Pauli Mariannick Maziére Holger C. Hansen Tetsuya Suhara Carl-Gunnar Swahn Per Karlsson Lars Farde 《European journal of nuclear medicine and molecular imaging》1997,24(10):1261-1267
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand
for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241.
This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised
by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake
of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after
injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with
flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection.
The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands
for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage.
Received 19 April and in revised form 10 June 1997 相似文献
32.
Hoschek Stefan Hoschek-Risslegger Ursula Fiegl Michael Zabernigg August Pall Georg Auberger Thomas Gunsilius Eberhard Schmid Thomas Jamnig Herbert Hilbe Wolfgang 《Wiener Medizinische Wochenschrift》2007,157(21):562-568
Wiener Medizinische Wochenschrift - Aggressives Tumorwachstum, frühe Metastasierung und hohe Assoziation mit intensivem Nikotinkonsum sind die Charakteristika des kleinzelligen... 相似文献
33.
U L Karlsson J J Augsburger J A Shields A M Markoe L W Brady R Woodleigh 《Ophthalmology》1989,96(3):382-388
The authors analyzed the clinical and follow-up data on 277 selected patients with primary choroidal or ciliochoroidal melanoma who were treated with 60Co plaque radiotherapy between 1976 and 1982. Local recurrence of the irradiated melanoma developed in 39 (14%) patients during the follow-up interval. The 5-year tumor recurrence rate (Kaplan-Meier) was estimated to be 12%. Multivariate prognostic factor analysis (Cox proportional hazards modeling) identified the largest linear tumor dimension and proximity of the posterior margin of the tumor to the optic nerve head as predictors of recurrence. The 5-year survival rate of patients whose tumors recurred (58%) was significantly (log-rank test P = 0.0023) worse than that of patients whose tumor remained clinically controlled (82%). 相似文献
34.
Closing patellar tendon defects after anterior cruciate ligament reconstruction: absence of any benefit 总被引:4,自引:2,他引:2
Sveinbjörn Brandsson E. Faxén Bengt I. Eriksson Peter Kälebo Leif Swärd Olof Lundin J. Karlsson 《Knee surgery, sports traumatology, arthroscopy》1998,6(2):82-87
The most common graft in anterior cruciate ligament (ACL) surgery involves using the central one-third of the patellar tendon.
Knowledge concerning the postoperative disability after harvesting the patellar tendon is, however, limited. The aim of this
study was to evaluate the impact patellar tendon suture and bone grafting of the patellar bone defect might have in terms
of functional outcome and patellofemoral pain after harvesting the bone-tendon-bone graft, compared with leaving the harvested
site non-sutured and non-grafted. Sixty patients, scheduled for arthroscopically assisted ACL reconstruction, were randomly
allocated to two groups. In group I, suture of the patellar tendon and bone grafting of the patellar defect were performed.
In group II, the tendon gap and the patellar defect were left open. Preoperatively, there was no significant difference between
the groups when comparing objective knee stability, as measured with a KT-1000 laxity meter, Lysholm score, Tegner activity
level, IKDC score, or patellofemoral pain score. Both groups had a significantly improved Lysholm score at the 2-year follow-up,
without any difference between them. Tegner's activity level was significantly lower at follow-up, compared with the pre-injury
level in both groups. The patellofemoral pain score improved significantly after the reconstruction, without any difference
between the groups. Ultrasonography did not reveal any difference between the groups in terms of healing of the tendon gap.
This study revealed no differences in donor site morbidity, functional outcome, patellofemoral pain score or knee joint stability
between the two treatment groups. The conclusion is that suture of the patellar tendon and bone grafting of the patellar defect
do not improve the functional results or reduce donor site morbidity after arthroscopically assisted ACL.
Received: 17 December 1996 Accepted: 30 July 1997 相似文献
35.
Per Karlsson Lars Farde Christer Halldin Carl-Gunnar Swahn Göran Sedvall Christian Foged Kristian Tage Hansen Birte Skrumsager 《Psychopharmacology》1993,113(2):149-156
The benzazepines NNC 687 and NNC 756 have in animal studies been described as selective D1-dopamine receptor antagonists. Both compounds have been labeled with11C for examination by positron emission tomography (PET). In the present study central receptor binding was studied in monkeys and healthy men. After IV injection of both radioligands in Cynomolgus monkeys radioactivity accumulated markedly in the striatum, a region with a high density of D1-dopamine receptors. This striatal uptake was displaced by high doses of the selective D1-antagonist SCH 23390 (2 mg/kg) but not by the 5HT2-antagonist ketanserin (1.5 mg/kg) or the selective D2-antagonist raclopride (3 mg/kg). The cortical uptake after injection of [11C]NNC 687 was not reduced in displacement experiments with ketanserin. The cortical uptake of [11C]NNC 756 was reduced in displacement and protection experiments with ketanserin by 24–28% (1.5 mg/kg), whereas no reduction could be demonstrated on striatal uptake. In healthy males both compounds accumulated markedly in the striatum. For [11C]NNC 687 the ratio of radioactivity in the putamen to cerebellum was about 1.5. For [11C]NNC 756 the ratio was about 5. This ratio of 5 for [11C]NNC 756 is the highest obtained so far for PET radioligands for the D1-dopamine receptor. 相似文献
36.
In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO‐blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100%(TiO‐blasted) vs 95.3%(machined), P =0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 tvues of implant after 2 years of loading, 0.04 (0.82) mm, P >0.30. 相似文献
37.
38.
Connective tissue growth factor expression and Smad signaling during mouse heart development and myocardial infarction. 总被引:5,自引:0,他引:5
Susana M Chuva de Sousa Lopes Alie Feijen Jeroen Korving Olexander Korchynskyi Jonas Larsson Stefan Karlsson Peter ten Dijke Karen M Lyons Roel Goldschmeding Pieter Doevendans Christine L Mummery 《Developmental dynamics》2004,231(3):542-550
Connective tissue growth factor (CTGF) is reported to be a target gene of transforming growth factor beta (TGFbeta) and bone morphogenetic protein (BMP) in vitro. Its physiological role in angiogenesis and skeletogenesis during mouse development has been described recently. Here, we have mapped expression of CTGF mRNA during mouse heart development, postnatal adult life, and after experimental myocardial infarction. Furthermore, we investigated the relationship between CTGF and the BMP/TGFbeta signaling pathway in particular during heart development in mutant mice. Postnatally, CTGF expression in the heart became restricted to the atrium. Strikingly, 1 week after myocardial infarction, when myocytes have disappeared from the infarct zone, CTGF and TGFbeta expression as well as activated forms of TGFbeta but not BMP, Smad effector proteins are colocalized exclusively in the fibroblasts of the scar tissue, suggesting possible cooperation between CTGF and TGFbeta during the pathological fibrotic response. 相似文献
39.
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