全文获取类型
收费全文 | 3171篇 |
免费 | 197篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 114篇 |
妇产科学 | 145篇 |
基础医学 | 309篇 |
口腔科学 | 129篇 |
临床医学 | 271篇 |
内科学 | 536篇 |
皮肤病学 | 83篇 |
神经病学 | 144篇 |
特种医学 | 117篇 |
外国民族医学 | 2篇 |
外科学 | 593篇 |
综合类 | 71篇 |
一般理论 | 3篇 |
预防医学 | 219篇 |
眼科学 | 94篇 |
药学 | 326篇 |
中国医学 | 21篇 |
肿瘤学 | 189篇 |
出版年
2023年 | 42篇 |
2022年 | 123篇 |
2021年 | 163篇 |
2020年 | 116篇 |
2019年 | 157篇 |
2018年 | 183篇 |
2017年 | 102篇 |
2016年 | 124篇 |
2015年 | 115篇 |
2014年 | 136篇 |
2013年 | 214篇 |
2012年 | 251篇 |
2011年 | 290篇 |
2010年 | 152篇 |
2009年 | 104篇 |
2008年 | 171篇 |
2007年 | 136篇 |
2006年 | 137篇 |
2005年 | 103篇 |
2004年 | 114篇 |
2003年 | 81篇 |
2002年 | 68篇 |
2001年 | 33篇 |
2000年 | 15篇 |
1999年 | 18篇 |
1998年 | 22篇 |
1997年 | 12篇 |
1996年 | 12篇 |
1995年 | 7篇 |
1994年 | 12篇 |
1993年 | 8篇 |
1992年 | 12篇 |
1991年 | 21篇 |
1990年 | 15篇 |
1989年 | 8篇 |
1988年 | 6篇 |
1987年 | 11篇 |
1985年 | 9篇 |
1984年 | 16篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1976年 | 9篇 |
1974年 | 4篇 |
1973年 | 4篇 |
1972年 | 5篇 |
1966年 | 5篇 |
排序方式: 共有3405条查询结果,搜索用时 15 毫秒
81.
Mostafa Behpour-Oskooee Abdollah Karimi Shirin Sayyahfar 《World journal of pediatrics : WJP》2014,10(3):281-283
Background
There are some risk factors being more vulnerable to Lemierre’s syndrome such as a hypercoagulable state.Methods
We report a rare case of Lemierre’s syndrome with ethmoid and maxillary sinusitis, bilateral mastoiditis, and sigmoid sinus thrombosis.Results
Genetic study revealed a double heterozygote status in the methylenetetrahydrofolate reductase gene including C677T and A1298C.Conclusion
It is suggested to screen patients with Lemierre’s syndrome for a hypercoagulable state to consider anticoagulant therapy. 相似文献82.
M.M. El-Dawlatly A.M. Abou-EL-Ezz F.A. El-Sharaby Y.A. Mostafa B.D.S. FDSRCS M.Sc. Ph.D. 《Journal of orofacial orthopedics》2014,75(3):213-225
Objective
The correction of some Angle Class II malocclusions requires distalization of the upper first molars via an induced orthopedic effect. In the present study, we tested the potential of using a mini-implant to achieve a modified zygomatic anchorage system for Class II correction.Materials and methods
Our study comprised 10 treated and 10 control Class II growing female subjects aged 10–12 years. Orthodontic mini-implants were placed in the zygomatic buttress to act as anchorage for the distalization. The follow-up period was 6 months; treatment changes were assessed by cone beam CT scans.Results
Compared to the control group, the treatment group showed significant retrusion of point A, anti-clockwise rotation of the maxillary plane, and a mean molar distalization of 2.92?±?0.69 mm with no extrusion, no tipping or buccal rolling. There was significant upper incisor intrusion (1.89?±?0.84 mm) with no changes in incisor inclination. No change in the mandibular plane angle was detected.Conclusion
Use of this technique allowed Class II correction with concomitant reduction in the visible gingiva in the treated subjects without the adverse effects experienced with other appliances. 相似文献83.
84.
Eissa Soleymani Sohrab Sayyadi Hossein Pazoki Mahdi Fakhar Elham Sadat Banimostafavi Mohsen Kolivand Lotfollah Davoodi Mostafa Soleymani 《Clinical Case Reports》2022,10(2)
Cystic echinococcosis is one of the most important zoonotic parasitic diseases caused by the tapeworm Echinococcus granulosus. To date, the genotype of multivesicular CE has not been identified. In this regard, the genotyping of multivesicular types of CE could help clinicians understand and manage the disease effectively. 相似文献
85.
Mohsen Al-Qhtani Ghulam M. Mustafa Nasheeta Mazhar Sonia Bouzgarrou Qasim Mahmood Abeer Mera Zaki I. Zaki Nasser Y. Mostafa Saad H. Alotaibi Mohammed A. Amin 《Materials》2022,15(1)
In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (Tc), spin polarization, half magnetic ferromagnetism and transport properties of ZnX2Se4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of Tc is perceived for ZnCr2Se4. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μB of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy crystal, exchange energies x(d), x (pd) and exchange constants (No and No ). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 1011 W/mK2) among studied compounds. 相似文献
86.
Basant Mostafa Gabr Afaf Sayed Ahmed Zamzam Eman Ahmed Eisa Ghada Foad El-Baradey Maii Atef Shams Eldeen 《急性病杂志》2021,10(3):117-121,中插1
Objectives: To identify and test the antibiotic susceptibility of nosocomial coliform bacilli and investigate the presence of oqxA and oqxB genes among the multidrug-resistant (MDR) phenotypes. Methods: One hundred and twenty different healthcare-associated infection samples were collected. Coliform bacilli were isolated, identified by conventional methods, and then antibiotic susceptibility tests were done using the VITEK2 system and disk diffusion methods. OqxAB operon was identified using a conventional PCR-based technique. oqxA and oqxB genes were compared between MDR Klebsiella pneumonia (K. pneumonia) phenotypes and MDR Escherichia coli (E. coli) phenotypes. Besides, oqxAB operons were compared between phenotypes of K. pneumonia and E. coli isolates. Results: Seventy coliform bacilli were isolated with the predominance of K. pneumonia and E. coli. Besides, 82.1% of K. pneumonia strains and 53.3% of E. coli isolates were MDR phenotypes. Significant more oqxB genes alone were found in MDR E. coli than that in MDR K. pneumoniae phenotypes (χ2=10.160, P=0.003). OqxAB operon was significantly more in MDR phenotypes of E. coli than that in the susceptible phenotypes (P<0.001). There was significantly less of this operon in susceptible E. coli isolates than that in susceptible K. pneumoniae isolates (P<0.001). OqxAB positive isolates that were also resistant to fluoroquinolones, tetracycline, trimethoprim, and chloramphenicol, most probably suggested functional pumps. Conclusions: MDR coliform bacilli are strongly implicated in healthcare-associated infection. Attention should be paid to the presence of oqxAB pump, as an important mechanism in the development of resistance against many antimicrobials because it contributes to co-resistance with other categories; therefore, this pump could be a good target for efflux pump inhibitors. 相似文献
87.
Islam M. Mostafa Muhammad Rehan Hasan Shah Gilani Yequan Chen Baohua Lou Jianping Li Guobao Xu 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2021,29(3):510
Developing new, cheap, sensitive and selective chemiluminescence (CL) systems with multiple detection properties is still a big challenge for biological and environmental applications. Here, we report a new CL system having multiple detection applications (environmental and biological). The developed lucigenin-pyrogallol system gave an enhancement (190 times) over the conventional lucigenin-H2O2 CL system. Cobalt ion and tyrosinase can inhibit lucigenin-PG CL intensity. Based on these phenomena, we have developed new CL methods for the detection of pyrogallol (LOD = 0.94 μM), lucigenin (LOD = 0.42 μM), cobalt (LOD = 68 nM), and tyrosinase (LOD = 1.8 μg/mL). Furthermore, the developed system gave excellent recoveries in real samples within the range of 93.59–103.12% for the assay of pyrogallol, Co2+ and tyrosinase in coffee, lake water, and human plasma, respectively. 相似文献
88.
Fatemeh Mohammadsaleh Maryam Dehdashti Jahromi Abdol Reza Hajipour Seyed Mostafa Hosseini Khodabakhsh Niknam 《RSC advances》2021,11(34):20812
1,2,3-Triazole is an interesting N-heterocyclic framework which can act as both a hydrogen bond donor and metal chelator. In the present study, C–H hydrogen bonding of the 1,2,3-triazole ring was surveyed theoretically and the results showed a good agreement with the experimental observations. The click-modified magnetic nanocatalyst Pd@click-Fe3O4/chitosan was successfully prepared, in which the triazole moiety plays a dual role as both a strong linker and an excellent ligand and immobilizes the palladium species in the catalyst matrix. This nanostructure was well characterized and found to be an efficient catalyst for the CO gas-free formylation of aryl halides using formic acid (HCOOH) as the most convenient, inexpensive and environmentally friendly CO source. Here, the aryl halides are selectively converted to the corresponding aromatic aldehydes under mild reaction conditions and low Pd loading. The activity of this catalyst was also excellent in the Suzuki cross-coupling reaction of various aryl halides with phenylboronic acids in EtOH/H2O (1 : 1) at room temperature. In addition, this catalyst was stable in the reaction media and could be magnetically separated and recovered several times.The C–H hydrogen bonding of a 1,2,3-triazole framework was studied. An Fe3O4–chitosan core–shell incorporating a triazole/Pd complex was investigated as a nanocatalyst in carbonylation and C–C coupling. 相似文献
89.
Mostafa H. Baky Marwa T. Badawy Alaa F. Bakr Nesrine M. Hegazi Ahmed Abdellatif Mohamed A. Farag 《RSC advances》2021,11(63):39680
Adansonia digitata L. also known as African baobab is one of the most important fruit-producing trees, widely distributed in the African continent. Baobab fruits are known to possess potential health benefits and nutritional value. This study aimed to holistically dissect the metabolome of A. digitata fruits using a novel comparative protocol using three different analytical platforms. Ultra high performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS/MS), and headspace solid-phase microextraction/gas chromatography coupled to mass spectrometry (HS-SPME/GC-MS) were respectively employed for phytonutrients and aroma profiling, whereas GC-MS post silylation provided an overview of nutrients i.e., sugars. UHPLC-HRMS/MS analysis allowed for the assignment of 77 metabolites, among which 50% are reported for the first time in the fruit. While GC-MS of silylated and aroma compounds led to the identification of 74 and 16 compounds, respectively. Finally, NMR-based metabolite fingerprinting permitted the quantification of the major metabolites for future standardization. In parallel, in vivo antidiabetic potential of the baobab fruit using a streptozotocin (STZ) induced diabetic rat model was assessed. Histopathological and immune-histochemical investigations revealed hepatoprotective and renoprotective effects of A. digitata fruit along with mitigation against diabetes complications. Moreover, the administration of A. digitata fruits (150 mg kg−1) twice a week lowered fasting blood glucose levels.Metabolites profiling of Adansonia digitata L. in relation to its biological activity. 相似文献
90.
Hani N. Mufti Ahmed A. Rabie Alyaa M. Elhazmi Husam A. Bahaudden Mostafa A. Rajab Ismael S. Al Enezi Ayed Y. Assiri Khalid A. Maghrabi Ali A. Al Bshabshe Abdullah M. Abudayah Adel A. Tash Awad A. Al-Omari Mohamed H. Azzam 《Saudi medical journal》2021,42(6):589
Extracorporeal membrane oxygenation (ECMO) is considered as a supportive treatment that provides circulatory and ventilatory support and can be thought off as a bridge to organ recovery. Since 2009, it has been applied as a rescue treatment for patients with severe adult respiratory distress syndrome (ARDS) mainly due to viral causes. In December 2019, several patients presented with a constellation of symptoms of viral pneumonia in China. A new strain of the corona virus family, called COVID-19, has been discovered to be the cause of this severe mysterious illness that was named severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2). This new virus continued to spread across the globe leading to the World Health Organization announcing it as a pandemic in the early 2020. By the end of March 2021, the number of COVID-19 cases worldwide exceeded 126 million cases. In Saudi Arabia, the first confirmed case of COVID-19 was reported in the 2nd March 2020. By the end of March 2021, the total number of confirmed COVID-19 cases in Saudi Arabia is just above 360,000. In anticipation of the need of ECMO for the treatment of patients with SARS‑CoV‑2 based on the previous Middle East respiratory syndrome coronavirus pandemic experience, the Saudi Extra-Corporeal Life Support (ECLS) chapter that is under the umbrella of the Saudi Critical Care Society (SCCS) convened a working group of ECMO experts. The mission of this group was to formulate a guidance for the use of ECMO as a last resort for patients with severe ARDS, especially with COVID-19 based on available evidence. The ECLS-SCCS chapter wanted to generate a document that can be used to simple guide, with a focus on safety, to provide ECMO service for patients with severe ARDS with a special focus on SARS‑CoV‑2. 相似文献