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151.
Akram A. Khosroabadi Palash Gangopadhyay Steven Hernandez Kyungjo Kim Nasser Peyghambarian Robert A. Norwood 《Materials》2015,8(8):5028-5047
We present a proof of concept for tunable plasmon resonance frequencies in a core shell nano-architectured hybrid metal-semiconductor multilayer structure, with Ag as the active shell and ITO as the dielectric modulation media. Our method relies on the collective change in the dielectric function within the metal semiconductor interface to control the surface. Here we report fabrication and optical spectroscopy studies of large-area, nanostructured, hybrid silver and indium tin oxide (ITO) structures, with feature sizes below 100 nm and a controlled surface architecture. The optical and electrical properties of these core shell electrodes, including the surface plasmon frequency, can be tuned by suitably changing the order and thickness of the dielectric layers. By varying the dimensions of the nanopillars, the surface plasmon wavelength of the nanopillar Ag can be tuned from 650 to 690 nm. Adding layers of ITO to the structure further shifts the resonance wavelength toward the IR region and, depending on the sequence and thickness of the layers within the structure, we show that such structures can be applied in sensing devices including enhancing silicon as a photodetection material. 相似文献
152.
Vibrio cholerae O139: How great is the threat of a pandemic? 总被引:3,自引:0,他引:3
A. K. Siddique K. Akram K. Zaman P. Mutsuddy A. Eusof R. B. Sack 《Tropical medicine & international health : TM & IH》1996,1(3):393-398
The emergence of the new strain Vibrio cholerae O139 and its rapid spread in Bangladesh and India together with its detection in several other countries, have raised the question whether this constitutes the beginning of the eighth pandemic of cholera, and if so, how large a threat it poses. In an attempt to answer this question, epidemic spread patterns of Vibrio cholerae O139 strain in Bangladesh were studied. Initially the epidemic moved quickly and affected the entire coastal and estuarine tidal plains of southern Bangladesh. In the flood plains of the northern regions it affected mostly the north‐eastern and north‐central areas, at a slower pace than in the southern areas. In the beginning the new strain totally displaced both biotypes (classic and El Tor ) of Vibrio cholerae O1. Nearly 2 years after its initial detection, striking differences in the distribution of V. cholerae O139 and O1 were observed. In most northern areas, the new strain was replaced by V. cholerae O1, whereas in the southern coastal regions, the O139 strain continues to dominate epidemics. The study suggests that the O139 strain may become endemic in the coastal ecosystem. The threat of a pandemic, therefore, may not be as large as it first seemed. 相似文献
153.
154.
Fatemeh Kamari Ghanavati Alireza Choobineh Sareh Keshavarzi Ali Asghar Nasihatkon Akram Sadat Jafari Roodbandi 《La Medicina del lavoro》2019,110(5):389
Background:Modern technology has reduced physical workload and imposed high mental workload on the control room operators in industrial settings. The present study was conducted among control room operators to assess their mental workload, investigate their workability, examine the relationship between mental workload and workability, and determine the factors associated with workability.Methods:This cross-sectional study was carried out among 213 control room operators in six Iranian process industries. Task Load Index (NASA-TLX) was used to assess the mental workload, and Work Ability Index (WAI) was used to determine workability. The relationships between demographic characteristics and dimensions of mental workload and workability were examined by univariate tests. Logistic regression analysis was also used to determine the factors associated with the operators’ workability.Results:The results showed a high mental workload in the study population (82.38±8.8). Yet, the operators showed a good and excellent level of workability (56.4%). Pearson’s correlation coefficient revealed a significant inverse linear relationship between the mean score of mental workload and workability (r=-0.581). Besides, regression modeling demonstrated that mental demand (OR=0.90), temporal demand (OR=0.90), effort (OR=0.91), frustration (OR=0.92), from NASA-TLX subscales were significantly associated with workability. Moreover, mental and temporal demands were important factors associated with reduced workability.Conclusion:Monitoring tasks imposes high mental workload on the control room operators, which may result in adverse effects on their workability as well as on the safety of the system.Key words: Mental workload, NASA-TLX, work ability, control room 相似文献
155.
Sera were collected from a total of 122 children, comprising 117 cases with undifferentiated fever and 5 cases with dengue
hemorrhagic fever (DHF), during June to September 1994 in Karachi, Pakistan. Sera were tested by the IgM-capture ELISA using
dengue type 1 (D1), dengue type 2 (D2), West Nile (WN), and Japanese encephalitis (JE) viral antigens. Among 92 single sera
from undifferentiated fever cases, IgM antibodies were detected in 5 cases by D1, 8 cases by D2, and 5 cases by WN antigens,
respectively. Corresponding number of positives among 25 paired sera from undifferentiated fever cases were 3 by D1, 6 by
02, and 1 by WN antigen. Four out of 5 DHF cases possessed anti-D1 as well as anti-D2 IgM antibodies. Only a single DHF case
was positive for anti-WN IgM antibodies. Anti-JE IgM antibodies were not detected in any of the tested serum specimens.
Clinical manifestations of undifferentiated fever patients were generally non specific, but the percentage of children with
anemia, hepatomegaly and splenomegaly was higher in patients possessing anti-dengue IgM antibodies than those without. Among
the groups with anti-dengue IgM antibodies, those possessing only anti-D2 but not anti-D1 IgM antibodies showed higher percentages
with cough, edema, and splenomegaly.
The results indicated that up to 26% of the undifferentiated fever cases were caused by dengue virus infection in Karachi,
Pakistan. 相似文献
156.
157.
158.
Reuben Ilia Carlos Cafri Jamal Jafari Jean Marc Weinstein Akram Abu-Ful Alexander Battler 《Catheterization and cardiovascular interventions》1997,41(2):170-173
Two cases of prolonged catheter-induced right coronary artery spasm, mimicking fixed stenoses, are presented. In one case, the spasm appeared at the same place in sequential catheterizations. This angiographic finding may be easily misinterpreted as a fixed lesion, leading to unnecessary attempts at angioplasty. Cathet. Cardiovasc. Diagn. 41:170–173, 1997. © 1997 Wiley-Liss, Inc. 相似文献
159.
Taiwo W. Quadri Lukman O. Olasunkanmi Ekemini D. Akpan Akram Alfantazi I. B. Obot Chandrabhan Verma Amal M. Al-Mohaimeed Eno E. Ebenso M. A. Quraishi 《RSC advances》2021,11(4):2462
Three novel N-hydrospiro-chromeno-carbonitriles namely, 2-amino-7,7-dimethyl-1′,3′,5-trioxo-1′,3′,5,6,7,8-hexahydrospiro[chromene-4,2′-indene]-3-carbonitrile (INH-1), 3-amino-7,7-dimethyl-2′,5-dioxo-5,6,7,8-tetrahydrospiro[chromene-4,3′-indoline]-2-carbonitrile (INH-2) and 3′-amino-7′,7′-dimethyl-2,5′-dioxo-5′,6′,7′,8′-tetrahydro-2H-spiro[acenaphthylene-1,4′-chromene]-2′-carbonitrile (INH-3) were synthesized using the principles of green chemistry and applied as corrosion inhibitors for mild steel in acidic medium using computational simulations and experimental methods. Experimental and computational studies revealed that inhibition effectiveness of the INHs followed the sequence: INH-3 (95.32%) > INH-2 (93.02%) > INH-1 (89.16%). The investigated compounds exhibit mixed-type corrosion inhibition characteristics by blocking the active sites on the surface of mild steel. EIS study revealed that the INHs behave as interface-type corrosion inhibitors. EDX analyses supported the adsorption mechanism of corrosion inhibition. A DFT study carried out for gaseous and aqueous forms of inhibitor molecules indicated that interactions of INHs with the mild steel surface involve charge transfer phenomenon or donor–acceptor interactions. A Monte Carlo (MC) simulation study revealed that only a fractional segment of the molecule lies parallel to the steel surface, since the INH molecules are not completely planar. The results of computational studies and experimental analyses were in good agreement.Three novel N-hydrospiro-chromeno-carbonitriles, INH-1, INH-2 and INH-3 were synthesized using the principles of green chemistry and applied as corrosion inhibitors for mild steel in acidic medium using computational simulations and experimental methods. 相似文献
160.
Veena R. Gujju Bushra Akram Dena R. Shibib Miranda A. McGhee Douglas A. Drevets 《Medicine》2021,100(51)
Rationale:Bordetella bronchiseptica is a common cause of upper respiratory tract infections in domesticated dogs and cats and a rare zoonotic pathogen in immunocompromised humans. With increasing numbers of people acquiring pets and spending time with them in confined spaces due to COVID-19 lockdowns, it is important to be aware of adverse health consequences brought about by this interaction. We present a case of B bronchiseptica pneumonia in a patient with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and review key characteristics of an additional 30 cases of B bronchiseptica infections in 29 patients with HIV/AIDS that were identified by literature review.Patient concerns:A 61-year-old male with HIV/AIDS who was not on antiretroviral therapy and had advanced immunosuppression with a CD4+ T-lymphocyte count of 3 cells/μL sought medical attention for multiple somatic issues including subjective fevers, shortness of breath, and intermittent chest pain.Diagnosis:Computed tomography of the chest identified bilateral nodular opacities in the lower lobes with scattered areas of ground glass opacities. B bronchiseptica was identified in sputum culture by mass spectrometry followed by supplementary biochemical testing.Interventions:Empiric broad-spectrum antibiotics were initiated and changed to levofloxacin after susceptibility testing was completed.Outcomes:The patient was discharged after symptomatic improvement with levofloxacin.Lessons:Pneumonia with interstitial infiltrates in the setting of advanced CD4 lymphocyte depletion is the most common clinical syndrome caused by B bronchiseptica in patients with HIV/AIDS, and may be accompanied by sepsis. Advanced immune suppression, as well as chronic medical conditions, for example, alcoholism, diabetes, and renal failure that compromise host defenses are also commonly found in cases of B bronchiseptica infection in patients who do not have HIV infection. Reported animal contact among patients was not universal. Isolates were susceptible to aminoglycosides, carbapenems, fluoroquinolones, but typically resistant to most cephalosporins. 相似文献