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81.
Yoshida A; Araki Y; Motoyama M; Kim SY; Sung H; Araki S; Miura K; Shirai M 《Human reproduction (Oxford, England)》1997,12(11):2499-2503
The objective of this study was to determine whether or not abnormalities
in the autosomal structure of the male partner have any influence on
fertilization and early embryo development after intracytoplasmic sperm
injection (ICSI). Thirty-seven couples in whom the male partners were
examined by the same andrologist were included in this study. Six couples
(group I) in whom the male partner possessed autosomal structural
abnormality underwent seven ICSI cycles. As a control group, 31 couples
(group II) in which the male partner was karyotypically normal underwent 41
ICSI cycles. Although the normal fertilization rates seen in group I were
significantly higher than those in group II (P < 0.05), there was no
significant difference in the cleavage rates between the two groups. We did
not perform the analysis of the female partner's chromosomes, but we
surmise that structural autosomal abnormalities in the male partner do not
adversely influence fertilization at ICSI and early development of embryos.
相似文献
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84.
Jeong WK Byun JH Lee SS Won HJ Kim KW Shin YM Kim PN Lee MG 《Journal of magnetic resonance imaging : JMRI》2011,33(4):889-897
Purpose:
To compare the image quality and diagnostic performance of 1‐ and 3‐h delayed‐phase MR images (DPIs) after gadobenate dimeglumine injection in detecting small hepatocellular carcinomas (HCCs) in cirrhotic patients.Materials and Methods:
Relative enhancement of the liver (REliver) and HCC (REHCC) and liver‐to‐lesion contrast‐to‐noise ratio (CNR) of HCC were measured quantitatively on 1‐ and 3‐h DPIs in 65 patients with 88 HCCs. For qualitative analysis, two radiologists independently evaluated three image sets in 19 patients with 25 HCCs ≤2 cm and in 16 controls without HCCs: conventional liver MR without DPI (set A), adding 1‐h DPI (set B), and adding 3‐h DPI (set C), using a 5‐point scale for diagnosing small HCCs. Diagnostic performance for small HCCs was analyzed using the alternative free‐response receiver operating characteristic method.Results:
Mean REliver (P = 0.013) and REHCC (P < 0.001) were significantly higher on 1‐h than on 3‐h DPI, whereas CNR was significantly higher on 3‐h than on 1‐h DPI (P = 0.001). Observer‐averaged figure of merit (FOM) was significantly higher for set C than for set A (0.942 versus 0.883; P = 0.013).Conclusion:
In cirrhotic patients, 3‐h DPI provides a higher liver‐to‐lesion contrast and a better diagnostic performance for small HCCs than 1‐h DPI. J. Magn. Reson. Imaging 2011;33:889–897. © 2011 Wiley‐Liss, Inc. 相似文献85.
Eui-Baek Byun Hye-Min Kim Nak-Yun Sung Mi-So Yang Woo Sik Kim DaeSeong Choi 《International journal of radiation biology》2018,94(4):403-416
Purpose: The changes in molecular structure and the physiological properties of a gamma-irradiated aloe-emodin were examined.Materials and methods: Aloe-emodin was gamma-irradiated at doses ranging from 0 to 150 kGy, and the molecular structure was then analyzed using high-performance liquid chromatography (HPLC). AGS cells were cultured in RPMI medium and treated gamma irradiated aloe-emodin. Cell viability was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis efficiency was investigated by cell cycle arrest, cell morphology, and signaling pathway. The structure of new radiolytic peak was identified by the hydrogen-nuclear magnetic resonance (1H NMR).Results: HPLC results showed that gamma irradiation induced new radiolytic peaks that were distinguishable from the aloe-emodin standard, and the area of new peaks was increased as the radiation dose increased. Gamma-irradiated aloe-emodin treatment significantly increased the cytotoxicity in AGS tumor cells. We also found that 150?kGy aloe-emodin increased the expression of Bax, cytosolic cytochrome c, PARP cleavage, and the activation of caspases-8, -9, -3, Bid, and Bcl-2. Treatment of 150?kGy aloe-emodin induced ROS production, DNA fragmentation, alterations of cell morphology, and the migration in AGS cells. Gamma-irradiated aloe-emodin induced an increase of sub-G1 phase and depolarization of mitochondrial membrane potential in AGS cells. We also confirmed that fractionated AEF1 (new radiolytic peak) induce the cell death, migration, an increase of sub-G1 phase and cytochrome c in a ROS-dependent manner.Conclusions: The radiolysis product (AEF1) of aloe-emodin transformed by gamma-irradiation strongly induced apoptotic cell death in AGS cells, indicating AEF1 is a potential candidate drug for use in anti-cancer drug. 相似文献
86.
Tae Yeon Jeon Hyung-Jin Kim Joon Young Choi In Ho Lee Sung Tae Kim Pyoung Jeon Keon Ha Kim Hong Sik Byun 《Neuroradiology》2009,51(4):265-271
Introduction Sinonasal inverted papilloma (IP) is known for high rate of associated malignancy. The purpose of this study was to identify
18F-FDG PET/CT findings of sinonasal IPs. We also tried to compare the PET/CT findings with the MR imaging findings.
Methods We retrospectively reviewed PET/CT and MR images of eight patients with sinonasal IP with (n = 6) or without (n = 2) coexistent squamous cell carcinoma (SCC). Particular attention was paid to correlate the PET/CT findings with the MR
imaging findings in terms of area distribution of standard uptake values (SUVs) and a convoluted cerebriform pattern (CCP).
Results In two benign IPs, the maximum SUVs measured 8.2 and 7.8, respectively (mean, 8.0). In both tumors, MR images demonstrated
a diffuse CCP. In six IPs with coexistent SCC, the maximum SUVs ranged from 13.3 to 31.9 (mean ± SD, 20.2 ± 6.6). In these
tumors, MR images demonstrated a diffuse CCP in two, a partial CCP in three, and no CCP in one. A wide discrepancy was noted
between MR imaging and PET/CT in terms of area distribution of a CCP and SUVs.
Conclusion In sinonasal lesions with MR imaging features of IP, 18F-FDG PET/CT demonstrating avid FDG uptake does not necessarily imply the presence of coexistent malignancy. In our small
series, although IPs containing foci of SCC had consistently higher SUVs than IPs without SCC, the limited literature on this
subject suggests that PET cannot be used reliably to make the distinction. 相似文献
87.
88.
Joonho Byun Wonhyoung Park Jung Cheol Park Jae Sung Ahn 《Journal of Korean Neurosurgical Society》2021,64(1):39
ObjectiveThe treatment of large aneurysms of the posterior circulation is complicated and remains challenging. We here analyzed our institutional clinical outcomes of large unruptured aneurysms of the posterior circulation. MethodsThis study included 56 patients who presented with a large (>10 mm) unruptured aneurysm of the posterior circulation between 2002 and 2018. ResultsThere were 18 (32.1%) male and 38 (67.9%) female patients, with a mean age of 53.4 years. The most common location was the vertebral artery, followed by the basilar tip and posterior cerebral artery. The median follow-up duration was 29 months. Eighteen patients (32.1%) were treated by transcranial surgery and 38 (67.9%) were treated by endovascular treatment (EVT). Posttreatment complications occurred in 16 patients (28.6%), with there being no significant difference between the transcranial surgery and EVT groups. Complete obliteration was achieved in 30 patients (53.6%), with there being no statistically significant difference between the transcranial surgery and EVT groups. Recurrence occurred in 17 patients (30.4%), and the rate of recurrence was higher in the EVT group than in the transcranial surgery group (39.5% vs. 11.1%, p=0.03). Forty-four (84%) of 56 patients showed a favorable functional outcome. In saccular aneurysm, EVT was negative predictor of worsening of functional status. ConclusionTreatment of these aneurysms harbors an inherent high risk of morbidity. No superiority was found between transcranial surgery and EVT in terms of complications and complete obliteration, but transcranial surgery showed a higher treatment durability than EVT. 相似文献
89.
Yu Zhang Woocheol Kwon Ho Yun Lee Sung Min Ko Sang-Ha Kim Won-Yeon Lee Suk Joong Yong Soon-Hee Jung Chun Sung Byun JunHyeok Lee Honglei Yang Junhee Han Jeanne B. Ackman 《Korean journal of radiology》2021,22(5):829
ObjectiveTo compare the diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3-tesla (3T) magnetic resonance imaging (MRI) and computed tomography (CT) for the detection of visceral pleural surface invasion (VPSI). Visceral pleural invasion by non-small-cell lung cancer (NSCLC) can be classified into two types: PL1 (without VPSI), invasion of the elastic layer of the visceral pleura without reaching the visceral pleural surface, and PL2 (with VPSI), full invasion of the visceral pleura.Materials and MethodsThirty-three patients with pathologically confirmed VPSI by NSCLC were retrospectively reviewed. Multidetector CT and contrast-enhanced 3T MRI with a free-breathing radial three-dimensional fat-suppressed volumetric interpolated breath-hold examination (VIBE) pulse sequence were compared in terms of the length of contact, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. Supplemental evaluation of the tumor-pleura interface (smooth versus irregular) could only be performed with MRI (not discernible on CT).ResultsAt the tumor-pleura interface, radial VIBE MRI revealed a smooth margin in 20 of 21 patients without VPSI and an irregular margin in 10 of 12 patients with VPSI, yielding an accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and F-score for VPSI detection of 91%, 83%, 95%, 91%, 91%, and 87%, respectively. The McNemar test and receiver operating characteristics curve analysis revealed no significant differences between the diagnostic accuracies of CT and MRI for evaluating the contact length, angle of mass margin, or arch distance-to-maximum tumor diameter ratio as predictors of VPSI.ConclusionThe diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3T MRI and CT were equal in terms of the contact length, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. The advantage of MRI is its clear depiction of the tumor-pleura interface margin, facilitating VPSI detection. 相似文献
90.
You Sung Kim Sung Eun Rha Soon Nam Oh Seung Eun Jung Yu Ri Shin Byung Gil Choi Jae Young Byun Eun Sun Jung Dong Goo Kim 《Korean journal of radiology》2010,11(5):560-565
Intrahepatic bile duct adenoma is a rare benign epithelial hepatic tumor derived from bile duct cells. We report the imaging findings of a patient with bile duct adenoma, which appeared as a small heterogeneously enhancing mass with focal small cystic change on CT and MRI. Follow-up images at seven months showed a slight increase in tumor size, which could be partly explained by intratumoral hemorrhage on pathologic examination. Although rare, bile duct adenoma should be considered as a differential diagnosis of a small hypervascular tumor located in the periphery of liver. Focal cystic change and intratumoral hemorrhage may occur. 相似文献