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71.
Maurizio Penco Anna Maria Villa Cristina Gobbi Mario Pegoraro Giuseppe Di Silvestro Julia S. Higgins 《Macromolecular chemistry and physics.》1992,193(12):3129-3137
Semi-interpenetrating networks (semi-IPN's) based on linear poly(phenylene ether)s and crosslinked polystyrene can be prepared by reactive moulding of crosslinkable polymeric mixtures. These materials show thermomechanical properties which strongly depend on both the ratio of the two polymeric matrices and the degree of crosslinking in the polystyrene network. Samples based on a 50/50 weight ratio of poly(2,6-dimethyl-1,4-phenylene oxide)/crosslinked polystyrene show glass transition temperatures (Tg) which are very dependent on the degree of crosslinking. It is therefore possible to obtain materials with desired Tg, ranging from the Tg of the corresponding linear blend to that of poly(2,6-dimethyl-1,4-phenylene oxide) alone. 相似文献
72.
Franz H Messerli Giuseppe Mancia Charles Richard Conti Carl J Pepine 《European heart journal》2006,27(23):2902-3; author reply 2903
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Use of the abdominal aorta for arterial input function determination in hepatic and renal PET studies. 总被引:2,自引:0,他引:2
G Germano B C Chen S C Huang S S Gambhir E J Hoffman M E Phelps 《Journal of nuclear medicine》1992,33(4):613-620
A method using the activity in the abdominal aorta of human and animal subjects to noninvasively estimate blood-pool input function in dynamic, abdominal PET scans is proposed and validated in this paper. Partial volume effects due to the aorta's dimensions are corrected by a semi-automated algorithm based on the transaxial resolution in the reconstructed images. The technique was validated by comparing PET measurements of abdominal aortic activity to well counter measurements of arterial blood samples (eight canine renal studies) and to PET measurements of left ventricular cavity activity (eight human hepatic studies). In renal studies, correlation analysis of the areas subtended by the two input functions yielded an essentially unitary slope (1.03 +/- 0.09), with high correlation (R2 greater than 0.95, p less than 0.001). In hepatic studies, similar values (0.99 +/- 0.03 and R2 greater than 0.85, p less than 0.001) were found. Correlation of the blood flow estimates based on the two input functions and a two-compartment model produced slopes of 1.07 +/- 0.16 and 1.03 +/- 0.07, and correlations of (R2 greater than 0.98, p less than 0.001) and (R2 greater than 0.97, p less than 0.001) for the renal and hepatic studies, respectively. We conclude that noninvasive, accurate measurements of the arterial input function by dynamic PET imaging are possible and represent a clinically viable alternative to arterial blood sampling. 相似文献
76.
77.
Francesca Lodato Maria Rosa Tamé Marco Montagnani Vittorio Sambri Giovanna Liguori Francesco Azzaroli Paolo Costigliola Gianluca Grazi Enrico Roda Giuseppe Mazzella 《Liver transplantation》2006,12(11):1711-1714
The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation. 相似文献
78.
Bartolo Zingone Elisabetta Rauber Giuseppe Gatti Aniello Pappalardo Bernardo Benussi Gabriella Forti Umberto Tognolli Marco Gabrielli 《European journal of cardio-thoracic surgery》2007,31(6):990-997
Objective: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. Methods: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable ‘surgery of the thoracic aorta’. All survivors were followed-up for 1–41 months (16 ± 12). Results: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p < 0.05) and 10.3% (p = 0.67) obtained by the EuroSCORE full model and without ‘aortic surgery’, respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24 h. Conclusion: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates. 相似文献
79.
Isidoro Di Carlo Elia Pulvirenti Adriana Toro Giuseppe Corsale 《World journal of surgery》2009,33(3):520-525
Background Laparoscopic cholecystectomy is now indisputably the gold standard for managing most gallbladder diseases. However, subversion
of the Calot triangle anatomy cannot always be managed by laparoscopy and often requires a laparotomy conversion. This report
discusses our patients treated with our personal technique.
Methods Patients undergoing subtotal cholecystectomy performed by the same surgeon with a personal technique from January 1999 to
December 2007 were considered for the present study. Sex, age, symptoms, co-morbidities, diagnostic modality, time between
hospitalization and surgery, length of postsurgical hospitalization, morbidity and mortality, and follow-up were assessed.
Results Four men and six women, aged 23 to 88 years, were included. Every patient had symptoms of acute cholecystitis. Four patients
had had symptoms for an average of 2.5 days and six for an average of 5.1 h. All patients were studied by ultrasonography,
and seven underwent computed tomography. The operation was performed within 48 h in all patients. The average hospital stay
from surgery to discharge was different for patients who underwent primary open cholecystectomy (10 days, range 5–16 days)
and those having a conversion after a laparoscopic attempt (7.8 days, range 4–16 days). During the postoperative period only
one patient presented a self-limiting biliary leak. No postoperative mortality occurred. At follow-up, any recurrences of
stone in the biliary tract or newly formed pouch were recorded.
Conclusions The results suggest that this new approach can be considered effective in every instance of subversion of the normal anatomy
of Calot’s triangle. 相似文献
80.
Guido Germano Paul B. Kavanagh Piotr J. Slomka Serge D. Van Kriekinge Geoff Pollard Daniel S. Berman 《Journal of nuclear cardiology》2007,14(4):433-454
Cedars-Sinai’s approach to the automation of gated perfusion single photon emission computed tomography (SPECT) imaging is
based on the identification of key procedural steps (processing, quantitation, reporting), each of which is then implemented,
in completely automated fashion, by use of mathematic algorithms and logical rules combined into expert systems. Our current
suite of software applications has been designed to be platform- and operating system-independent, and every algorithm is
based on the same 3-dimensional sampling scheme for the myocardium. The widespread acceptance of quantitative software by
the nuclear cardiology community (QGS alone is used at over 20,000 locations) has provided the opportunity for extensive validation
of quantitative measurements of myocardial perfusion and function, in our opinion, helping to make nuclear cardiology the
most accurate and reproducible modality available for the assessment of the human heart. 相似文献