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Worm PV Ferreira NP Ferreira MP Kraemer JL Lenhardt R Alves RP Wunderlich RC Collares MV 《The Journal of craniofacial surgery》2012,23(3):650-653
Current methods to evaluate the biologic development of bone grafts in human beings do not quantify results accurately. Cranial burr holes are standardized critical bone defects, and the differences between bone powder and bone grafts have been determined in numerous experimental studies. This study evaluated quantitative computed tomography (QCT) as a method to objectively measure cranial bone density after cranial reconstruction with autografts. In each of 8 patients, 2 of 4 surgical burr holes were reconstructed with autogenous wet bone powder collected during skull trephination, and the other 2 holes, with a circular cortical bone fragment removed from the inner table of the cranial bone flap. After 12 months, the reconstructed areas and a sample of normal bone were studied using three-dimensional QCT; bone density was measured in Hounsfield units (HU). Mean (SD) bone density was 1535.89 (141) HU for normal bone (P < 0.0001), 964 (176) HU for bone fragments, and 453 (241) HU for bone powder (P < 0.001). As expected, the density of the bone fragment graft was consistently greater than that of bone powder. Results confirm the accuracy and reproducibility of QCT, already demonstrated for bone in other locations, and suggest that it is an adequate tool to evaluate cranial reconstructions. The combination of QCT and cranial burr holes is an excellent model to accurately measure the quality of new bone in cranial reconstructions and also seems to be an appropriate choice of experimental model to clinically test any cranial bone or bone substitute reconstruction. 相似文献
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Hyperthyroidism is a questionable risk factor for thromboembolism among patients with atrial fibrillation. Objective To correlate clinical risk factors for thromboembolism from a group of patients with atrial fibrillation related to hyperthyroidism with transoesophageal echocardiography (TOE) markers of a thrombogenic milieu. Design Clinical risk factors for thromboembolism, thyroid hormonal status, time since diagnosis of hyperthyroidism and TOE markers of a thrombogenic milieu were assessed in consecutive patients with atrial fibrillation related to hyperthyroidism. The following TOE parameters were assessed to define the presence of thrombogenic milieu: dense spontaneous echo contrast, thrombi or left atrial appendage blood flow velocities <0·20 m/s. Clinical risk factors for thromboembolism were based on CHADS2 (Cardiac failure, Hypertension, Age, Diabetes and Stroke) classification. Patients This study included 31 consecutive patients aged between 18 and 65 years with atrial fibrillation related to hyperthyroidism scheduled for TOE. Results Thrombogenic milieu was present in 14 of 31 (45·2%) patients. The thyroid status could not predict the presence of a thrombogenic milieu. Despite low CHADS2 score of 0/1, 6 of 13 (46·1%) patients had a thrombogenic milieu, whereas 10 of 18 (55·6%) patients with score ≥2 had none. The probability of having a thrombogenic milieu did not correlate with the number of clinical risk factors. Conclusion Among patients younger than 65 years of age with atrial fibrillation related to hyperthyroidism, there is no association between clinical risk factors with TOE markers of a thrombogenic milieu. TOE adds useful information that may affect antithrombotic therapy guided by clinical risk classification. 相似文献
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Patricia Garcia Dayse Alencar Pablo Pinto Ney Santos Claudio Salgado Vinicius A. Sortica Mara H. Hutz ?ndrea Ribeiro-dos-Santos Sidney Santos 《Clinical and Vaccine Immunology : CVI》2013,20(10):1599-1603
Leprosy is an infectious disease caused by Mycobacterium leprae characterized by dermatoneurological signs and symptoms that has a large number of new cases worldwide. Several studies have associated interleukin 10 with susceptibility/resistance to several diseases. We investigated haplotypes formed by three single nucleotide polymorphisms (SNPs) located in the IL10 gene (A-1082G, C-819T, and C-592A) in order to better understand the susceptibility to and severity of leprosy in an admixed northern Brazil population, taking into account estimates of interethnic admixture. We observed the genotypes ACC/ACC (P = 0.021, odds ratio [OR] [95% confidence interval (CI)] = 0.290 [0.085 to 0823]) and ACC/GCC (P = 0.003, OR [95% CI] = 0.220 [0.504 to 0.040]) presenting significant results for protection against leprosy development, framed in the profiles of low and medium interleukin production, respectively. Therefore, we suggest that genotypes A-1082G, C-819T, and C-592A formed by interleukin-10 polymorphisms are closely related to protection of the leprosy development in an admixed northern Brazil population, in particular ACC/ACC and ACC/GCC genotypes. 相似文献
47.
Silvia Mazzali Verst Andrea Caivano Sucena Marcos Vinicius Calfat Maldaun Paulo Henrique Pires Aguiar 《Acta neurochirurgica》2013,155(10):1863-1869
Background
Intraoperative neurophysiology monitoring (IOM) is a valuable tool in cerebellopontine angle (CPA) surgeries posing risk to the cranial nerves. Transcranial electrical stimulation (TES) for cranial nerves has been performed in the last 7 years, for obtaining the facial nerve motor evoked potential (MEP), using either C3/C4-Cz or C3-C4 (or inverse) stimulating points, which have been correlated with facial nerve functional outcome.Method
Intraoperative surgical and electrophysiological findings were documented prospectively. Patient files were reviewed for clinical data. We studied 23 patients undergoing CPA tumor resection using C5 or C6-Cz montage for TES, and were able to determine the correlation between facial nerve functional outcome and the amplitude drop of facial MEP above 50 %. Patients were evaluated for immediate facial nerve outcome and 6 months after the surgery. Follow-up was performed by structured telephone interviews with local physicians.Results
The sensibility of the studied parameters was 92.8 % for amplitude drop of facial nerve MEP, with positive predictive value of 81.2 %. The absence of changes during IOM has shown a negative predictive value of 100 %.Conclusion
In this series, the used montage was effective in predicting new facial deficit. 相似文献48.
Vinicius Rangel Geraldo-Martins Cesar Penazzo Lepri Regina Guenka Palma-Dibb 《Lasers in medical science》2013,28(1):33-39
The objective of this study was to evaluate the effects of chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation on the acid resistance of dental enamel. Forty human enamel samples were divided into four groups. They were manually irradiated with an Er,Cr:YSGG laser device (λ?=?2.78 µm, 20 Hz, 20 s), in a scanning mode, with and without water cooling, according to the following parameters: Group 1: 0.25 W, 62.5 J/cm2, no water cooling; group 2: 0.25 W, 62.5 J/cm2, 5.0 ml/min; group 3: 0.5 W, 125 J/cm2, no water cooling; group 4: 0.5 W, 125 J/cm2, 5.0 ml/min. No airflow was used. Afterwards, the samples were submitted to an acid challenge and assessed by cross-sectional Knoop microhardness at different depths (20, 40, 60, 80, and 100 µm) from the outer enamel surface. Average values were obtained for both irradiated and control areas in each sample and they were compared to obtain a percentage of microhardness increase. Data were analyzed by analysis of variance and Fisher’s exact test (α?=?5%). The percentage of microhardness increase observed in group 1 (+23.58%) was similar to group 3 (+19.12%), but higher than groups 2 (+3.61%) and 4 (10.9%) (p?<?0.05). The comparison of the depths showed that the Er,Cr:YSGG laser acted in the superficial layers of the dental enamel. The findings of the present study suggest that the energy densities of 62.5 and 125 J/cm2 were capable of increasing the acid resistance of human enamel. The presence of water during irradiation makes it difficult to obtain an enamel surface more resistant to acids. 相似文献
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Herman P Coelho FF Perini MV Lupinacci RM D'Albuquerque LA Cecconello I 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2012,14(6):390-395