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31.
Noweir MH Oman HA Abbas FI Abou-Taleb AM Mansour TA 《The Journal of the Egyptian Public Health Association》1993,68(3-4):405-442
The present study comprised 1000 child and young workers in small and medium-size industries in Alexandria, as well as 250 control subjects. Almost all young workers work for more than 40 hours/week and suffer from fatigue. Workers' family needs rather than the lack of family care is the responsible factor for sending the child to work, and the economic problems seem to be the underlying factor for all other problems of child labour. Work improves labourers' socio-economic status and smoking habit, and provides a chance for their personal contacts and interactions, which are reflected on their level of intellectual capabilities; however, it has some impact on their food habits affecting their achievement of balanced diet; and no drug addiction exists among all the studied subjects. Noise and dust represent the main occupational exposures (84.4% and 55.8% respectively), followed by exposure to heat (25.3%), vapors and gases (10.4%) and biological materials (9.0%), and nearly 2/3 of the workers have combined exposures. Work injuries occurred to 18.4% of the workers and 7.4% had more than one injury during employment; however, nearly 1/3 of the injuries required absenteeism off work and/or hospitalization. The injuries have been typically related to industrial operations, occurring mostly to hands and fingers (80.4%), and are mainly attributed to lack of training (63.0%). The health services presented to the workers are very poor. The study has been concluded by recommending making the work safe, free from hazards, and ergonomically fit to children, providing educational and training services, covering young workers by social security, and revising legislation of child labour. 相似文献
32.
Khan P Abbas S Cheeseman S Ranson M McGown AT 《Journal of chromatography. B, Biomedical sciences and applications》1999,721(2):279-284
A HPLC assay and solid-phase extraction technique from human plasma has been developed and validated for the novel anticancer agent CT2584, 1-(11-dodecylamino-10-hydroxyundecyl)-3,7-dimethylxanthine, which has recently completed a phase I trial at the Christie Hospital, Manchester under the auspices of the CRC phase I/II committee. Following addition of CT2576, 1-(11-octylamino-10-hydroxylundecyl)-3,7-dimethylxanthine, as internal standard, a solid-phase extraction cartridge (100 mg cyanopropyl) was used to isolate the drug CT2584 from human plasma. Analysis was performed by reversed-phase chromatography. CT2576 was used as internal standard at a concentration of 4 microg ml(-1) for the quantification of CT2584 from plasma for the duration of this work. The lower limit of quantification for the drug CT2584 in buffer using this assay was found to be 0.0122 microM (0.008 microg ml(-1)) and 0.048 microM (0.027 microg ml(-1)) when extracted from human plasma. 相似文献
33.
The effect of bradykinin and its antagonist on survival time after coronary artery occlusion in hypertensive rats 总被引:1,自引:0,他引:1
It is known that BK does play a role in the cardioprotective effect of angiotensin converting enzyme (ACE) inhibitors. The present study therefore was conducted to examine the effects of bradykinin (BK) and its antagonist on survival time in spontaneously hypertensive rats (SHR) with coronary artery ligation for 15 min and continuously. We also evaluated the heart rate and blood pressure (BP) in the presence and absence of BK and BK2 receptor antagonist, D-Arg-[Hyp-D-Phe7]BK. Coronary artery was ligated in anaesthetized rats and they were artificially ventilated with room air (stroke volume, 4 ml; 48 strokes/min) as described by the previous investigators. Lead II elecrocardiogram (ECG) was recorded from subcutaneous steel needle electrodes. Results of this investigation indicated that BK treatment 4 microg/kg (i.v.) and 8 microg/kg (i.v.) caused significant (P < 0.05) increase in survival time in SHR with coronary artery ligation for 15 min and continuously as compare to their respective saline-treated controls. However, BK antagonist treatment 4 microg/kg (i.v.) abolished the increase in survival time caused by BK treatment. The mean values of survival time between the saline-treated and BK antagonist plus BK-treated rats did not differ significantly (P > 0.05). The heart rate and BP responses were greatly reduced (P < 0.001) in the presence of coronary artery ligation. These findings suggest that BK might have cardioprotective effect to increase the survival time in rats by activating BK2 receptors after coronary artery ligation. 相似文献
34.
35.
Safeer Abbas Ali Ahmed Ayesha Waheed Wasim Abbass Muhammad Yousaf Sbahat Shaukat Hisham Alabduljabbar Youssef Ahmed Awad 《Materials》2022,15(10)
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion. 相似文献
36.
Farooq Anwar Ali Abbas Tahir Mehmood Anwarul‐Hassan Gilani Najeeb‐ur Rehman 《Phytotherapy research : PTR》2019,33(10):2548-2570
The genus Mentha comprises several aromatic species, which are cultivated world‐over due to their distinct aroma and commercial value. In addition to traditional food flavoring uses, Mentha are well recognized for their folk medicinal uses, especially to treat cold, fever, and digestive and cardiovascular disorders. A number of biological activities such as antioxidant, antimicrobial, biopesticidal, antitumor, anticancer, antiviral, antiallergic, antiinflammatory, antihypertensive, and urease inhibitory activity have been ascribed to Mentha. The traditional pharmacological attributes of Mentha herbs can be linked to the occurrence of bioactive phytochemicals such as terpenoids, alcohols, rosmarinic acid, and antioxidant phenolics among others. A rich source of bioactives, different species of Mentha, can be explored as a promising candidate for the development of nutra‐pharmaceuticals. This review covers the nutritional, phytochemical, and traditional medicinal aspects and multiple biological activities of some commonly available species of Mentha so as to explore their potential applications for nutra‐pharmaceutical and cosmo‐nutraceutical industry. Detailed chemical profile and pharmaceutical attributes of various Mentha essential oils are also covered. Moreover, based on computational analysis, quantitative chemical component–antioxidant activity relationship model is reviewed to predict and correlate structure–activity relationship of potential bioactives in selected Mentha essential oils leading to discovery and developmenmt of novel natural drugs. 相似文献
37.
Abdolhalim Rajabi Abbas Rezaianzadeh Abdolreza Rajaeefard Sareh Keshavarzi Kamran B. Lankarani 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3622-3628
Objective: Assessment of the contribution of non-medical factors to mode of delivery and birth preference in Iranian pregnant women in southwestern Iran.Study design: This cohort study used data from a structured questionnaire completed in early pregnancy and information about the subsequent delivery obtained through personal contact. Women were recruited by random sampling from antenatal clinics when scheduling visits over the course of 5 weeks from December 2012 to February 2013 and were followed-up 1 month after birth. Of the 2199 women recruited, 99.63% were eligible for the study.Results: Of the 748 women who expressed a desire to deliver their babies by cesarean section (CS) in early pregnancy, 87% had an elective cesarean section. The logistic regression analyses showed that normative beliefs (odds ratio [OR] 1.792, 95% confidence interval (1) 1.073–2.993), control beliefs (OR: 0.272, 95% CI: 0.162–0.459), and evaluation of outcomes (OR: 0.431, 95% CI: 0.268–0.692) favored the preference for cesarean section. The desire for delivery by elective cesarean section was associated with normative beliefs (OR: 1.138; 95% CI: 1.001–1.294), control beliefs (OR: 0.804; 95% CI: 0.698–0.927), and expectations about maternity care (OR: 0.772; 95% CI: 0.683–0.873), medical influences (OR: 1.150; 95% CI: 1.023–1.291), evaluation of outcome (OR: 0.789; 95% CI: 0.696–0.894), age, preference for cesarean section (OR: 5.445; 95% CI: 3.928–7.546), spouse educational level, and number of live births.Conclusions: A woman’s preference for delivery by cesarean section influenced their subsequent mode of delivery. Asking women in early pregnancy about their preferred mode of delivery provides the opportunity to extend their supports which might reduce the rate of elective cesarean section. This decision is affected by age, spouse educational level, number of live births, and preconceived maternal attitudes about delivery. 相似文献
38.
There is an interesting potential for the use of GFRP-pultruded profiles in hybrid GFRP-concrete structural elements, either for new constructions or for the rehabilitation of existing structures. This paper provides experimental and numerical investigations on the flexural performance of reinforced concrete (RC) specimens composite with encased pultruded GFRP I-sections. Five simply supported composite beams were tested in this experimental program to investigate the static flexural behavior of encased GFRP beams with high-strength concrete. Besides, the effect of using shear studs to improve the composite interaction between the GFRP beam and concrete as well as the effect of web stiffeners of GFRP were explored. Encasing the GFRP beam with concrete enhanced the peak load by 58.3%. Using shear connectors, web stiffeners, and both improved the peak loads by 100.6%, 97.3%, and 130.8%, respectively. The GFRP beams improved ductility by 21.6% relative to the reference one without the GFRP beam. Moreover, the shear connectors, web stiffeners, and both improved ductility by 185.5%, 119.8%, and 128.4%, respectively, relative to the encased reference beam. Furthermore, a non-linear Finite Element (FE) model was developed and validated by the experimental results to conduct a parametric study to investigate the effect of the concrete compressive strength and tensile strength of the GFRP beam. The developed FE model provided good agreement with the experimental results regarding deformations and damaged patterns. 相似文献
39.
Mohammed S. Alqahtani Mohamed Abbas Mohammed Abdulmuqeet Abdullah S. Alqahtani Mohammad Y. Alshahrani Abdullah Alsabaani Murugan Ramalingam 《Materials》2022,15(14)
The COVID-19 pandemic has the tendency to affect various organizational paradigm alterations, which civilization hasyet to fully comprehend. Personal to professional, individual to corporate, and across most industries, the spectrum of transformations is vast. Economically, the globe has never been more intertwined, and it has never been subjected to such widespread disruption. While many people have felt and acknowledged the pandemic’s short-term repercussions, the resultant paradigm alterations will certainly have long-term consequences with an unknown range and severity. This review paper aims at acknowledging various approaches for the prevention, detection, and diagnosis of the SARS-CoV-2 virus using nanomaterials as a base material. A nanostructure is a material classification based on dimensionality, in proportion to the characteristic diameter and surface area. Nanoparticles, quantum dots, nanowires (NW), carbon nanotubes (CNT), thin films, and nanocomposites are some examples of various dimensions, each acting as a single unit, in terms of transport capacities. Top-down and bottom-up techniques are used to fabricate nanomaterials. The large surface-to-volume ratio of nanomaterials allows one to create extremely sensitive charge or field sensors (electrical sensors, chemical sensors, explosives detection, optical sensors, and gas sensing applications). Nanowires have potential applications in information and communication technologies, low-energy lightning, and medical sensors. Carbon nanotubes have the best environmental stability, electrical characteristics, and surface-to-volume ratio of any nanomaterial, making them ideal for bio-sensing applications. Traditional commercially available techniques have focused on clinical manifestations, as well as molecular and serological detection equipment that can identify the SARS-CoV-2 virus. Scientists are expressing a lot of interest in developing a portable and easy-to-use COVID-19 detection tool. Several unique methodologies and approaches are being investigated as feasible advanced systems capable of meeting the demands. This review article attempts to emphasize the pandemic’s aftereffects, utilising the notion of the bullwhip phenomenon’s short-term and long-term effects, and it specifies the use of nanomaterials and nanosensors for detection, prevention, diagnosis, and therapy in connection to the SARS-CoV-2. 相似文献
40.
Khoobi M Emami S Dehghan G Foroumadi A Ramazani A Shafiee A 《Archiv der Pharmazie》2011,344(9):588-594
Coumarin and benzothiazole scaffolds can be found in a number of natural or synthetic antioxidants. In an effort to develop a novel radical scavenger and potential antioxidant, a series of coumarin derivatives containing 2‐methylbenzothiazoline motif and related compounds was synthesized and evaluated for their DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) and ABTS?+ (2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radicals scavenging activities. Among them, 7‐hydroxy‐3‐(2‐methyl‐2,3‐dihydrobenzo[d]thiazol‐2‐yl)‐2H‐chromen‐2‐one ( 3e ) has shown a significant free radical scavenging activity. From the structure–activity point of view, it was found that phenolic coumarin ring and benzothiazoline moiety in target compounds may contribute to the scavenging activity against free radicals. 相似文献