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Duzgun Yildirim Ovunc Ozturk Onur Tutar Fuad Nurili Halil Bozkurt Huseyin Kayadibi 《Renal failure》2014,36(8):1278-1282
Purpose: Urinary stones are common and can be diagnosed with computed tomography (CT) easily. In this study, we aimed to specify the opacity characteristics of various types of calcified foci that develop through the urinary system by using an image analysis program. With this method, we try to differentiate the calculi from the non-calculous opacities and also we aimed to present how to identify the characteristic features of renal and ureteral calcules. Materials and methods: We obtained the CT studies of the subjects (n?=?48, mean age?=?41 years) by using a dual source CT imaging system. We grouped the calculi detected in the dual-energy CT sections as renal (n?=?40) or ureteric (n?=?45) based on their locations. Other radio-opaque structures that were identified outside but within close proximity of the urinary tract were recorded as calculi “mimickers”. We used ImageJ program for morphological analysis. All the acquired data were analyzed statistically. Results: According to thorough morphological parameters, there were statistically significant differences in the angle and Feret angle values between calculi and mimickers (p?0.001). Multivariate logistical regression analysis showed that Minor Axis and Feret angle parameters can be used to distinguish between ureteric (p?=?0.003) and kidney (p?=?0.001) stones. Conclusions: Computer-based morphologic parameters can be used simply to differentiate between calcular and noncalcular densities on CT and also between renal and ureteric stones. 相似文献
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Hayri Ogul Mecit Kantarci Berhan Pirimoglu Leyla Karaca Bulent Aydinli Aylin Okur Gurkan Ozturk Yesim Kizrak 《Clinical transplantation》2014,28(3):354-360
The aim of this study was to evaluate utility of gadoxetic acid disodium (Gd‐EOB‐DTPA)‐enhanced magnetic resonance cholangiography (MRC) for the detection of biliary complications after living donor liver transplantation (LDLT). A total of 18 patients with suspected biliary complications underwent MRC. T2‐weighted MRC and contrast‐enhanced MRC (CE‐MRC) were used to identify the biliary complications. MRC included routine breath‐hold T2‐weighted MRC using half‐Fourier acquisition single‐shot turbo spin‐echo (HASTE) sequences and Gd‐EOB‐DTPA‐enhanced MRC T1‐weighted volumetric interpolated breath‐hold examination (VIBE) sequences. Before confirming the biliary complications, one observer reviewed the MRC images and the CE‐MRC images separately. The verification procedures and MRC findings were compared, and the sensitivity, specificity, and accuracy of both techniques were calculated for the identification of biliary complications. The observer found six of seven biliary complications using CE‐MRC. The sensitivity was 85.7% and the accuracy was 94.4%. Using MRC alone, sensitivity was 57.1% and accuracy was 55.5%. The accuracy of Gd‐EOB‐DTPA‐enhanced MRC was superior to MRC in locating biliary leaks (p < 0.05). The usage of Gd‐EOB‐DTPA‐enhanced MRC yields information that complements the MRC findings that improve the identification of biliary complications. We recommend the use of MRC in addition to Gd‐EOB‐DTPA‐enhanced MRC to increase the preoperative accuracy when assessing the biliary complications after LDLT. 相似文献
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Thiophene-based conjugated polymers hold an irreplaceable position among the continuously growing plethora of conjugated polymers due to their exceptional optical and conductive properties, which has made them a centre of attention for the past few decades and many researchers have contributed tremendously by designing novel strategies to reach more efficient materials for electronic applications. This review aims to highlight the recent (2012–2019) findings in design and synthesis of novel thiophene-based conjugated polymers for optical and electronic devices using organometallic polycondensation strategies. Nickel- and palladium-based protocols are the main focus of this account. Among them nickel-catalyzed Kumada catalyst-transfer polycondensation, nickel-catalyzed deprotonative cross-coupling polycondensation, palladium-catalyzed Suzuki–Miyaura and Migita–Kosugi–Stille couplings are the most popular strategies known so far for the synthesis of functionalized regioregular polythiophenes exhibiting fascinating properties such as electronic, optoelectronic, chemosensitivity, liquid crystallinity and high conductivity. This account also presents a brief overview of direct arylation polymerization (DArP) protocol that has shown a great potential to lessen the drawbacks of conventional polymerization techniques. DArP is a cost-effective and green method as it circumvents the need for the synthesis of arylene diboronic acid/diboronic ester and distannyl arylenes using toxic precursors. DArP also puts off the need to preactivate the C–H bonds, hence, presenting a facile route to synthesize polymers with controlled molecular weight, low polydispersity index, high regioregularity and tunable optoelectronic properties using palladium-based catalytic systems.Thiophene-based conjugated polymers are important conjugated polymers due to their exceptional optical and conductive properties, over the past few decades many researchers have designed novel strategies to reach more efficient materials for electronic applications. 相似文献
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Ismail Bozkurt Yasar Ozturk Guven Guney Burak Arslan Ozlem Gulbahar Yahya Guvenc Salim Senturk Mesut Emre Yaman 《International journal of clinical and experimental pathology》2022,15(1):20
Traumatic brain injury (TBI) continues to be a significant public healthcare concern. Neuroinflammation that occurs in the secondary phase of TBI leads to cognitive and physical dysfunction. A number of therapeutic modalities have been evaluated in an attempt to find a suitable treatment. The only drug approved for the treatment of idiopathic pulmonary fibrosis, pirfenidone, has been evaluated for its antifibrotic, anti-inflammatory, and anti-oxidant properties for various disorders, but this is the first study to examine its effects in an experimental TBI model. Twenty-four Wistar rats were randomly divided into three groups: control, trauma, and pirfenidone. The two latter groups underwent experimental diffuse cortical injury mimicking TBI. Neurological assessment was performed using the Garcia test, histological analysis was performed to examine neuroprotective and anti-inflammatory effects, and biochemical analyses of neuron-specific enolase (NSE), S-100B, caspase-3, and thiobarbituric acid reactive substances were performed. The pirfenidone group had a better Garcia test score (P=0.001), an increased anti-inflammatory effect (P<0.001), and an enhanced neuroprotective effect (P=0.007) along with decreased NSE, S100B, and TBARS levels compared to the trauma group. However, pirfenidone did not show a beneficial effect on caspase-3 levels. Pirfenidone may help decrease mortality and morbidity rates after TBI through its anti-inflammatory and antioxidant effects. 相似文献
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Serdar Durdagi Timucin Avsar Muge Didem Orhan Muge Serhatli Bertan Koray Balcioglu Hasan Umit Ozturk Alisan Kayabolen Yuksel Cetin Seyma Aydinlik Tugba Bagci-Onder Saban Tekin Hasan Demirci Mustafa Guzel Atilla Akdemir Seyma Calis Lalehan Oktay Ilayda Tolu Yasar Enes Butun Ece Erdemoglu Alpsu Olkan Nurettin Tokay eyma Ik Aysenur Ozcan Elif Acar Sehriban Buyukkilic Yesim Yumak 《Molecular therapy》2022,30(2):963
Small molecule inhibitors have previously been investigated in different studies as possible therapeutics in the treatment of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In the current drug repurposing study, we identified the leukotriene (D4) receptor antagonist montelukast as a novel agent that simultaneously targets two important drug targets of SARS-CoV-2. We initially demonstrated the dual inhibition profile of montelukast through multiscale molecular modeling studies. Next, we characterized its effect on both targets by different in vitro experiments including the enzyme (main protease) inhibition-based assay, surface plasmon resonance (SPR) spectroscopy, pseudovirus neutralization on HEK293T/hACE2+TMPRSS2, and virus neutralization assay using xCELLigence MP real-time cell analyzer. Our integrated in silico and in vitro results confirmed the dual potential effect of montelukast both on the main protease enzyme inhibition and virus entry into the host cell (spike/ACE2). The virus neutralization assay results showed that SARS-CoV-2 virus activity was delayed with montelukast for 20 h on the infected cells. The rapid use of new small molecules in the pandemic is very important today. Montelukast, whose pharmacokinetic and pharmacodynamic properties are very well characterized and has been widely used in the treatment of asthma since 1998, should urgently be completed in clinical phase studies and, if its effect is proved in clinical phase studies, it should be used against coronavirus disease 2019 (COVID-19). 相似文献