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991.
992.
The vertical distribution of polychlorinated biphenyls (PCBs) was measured in a dated sediment core from the northwestern Arabian Gulf to reconstruct their depositional history. The downcore profile showed an increase in concentrations from depth to a subsurface maximum of approximately 1,500 pg g−1 in approximately 1991, followed by an exponential decrease to the sediment–water interface. Current concentrations of ΣPCBs are similar to levels predating the episodic input of PCBs in sediments dated coincident with the 1991 Arabian Gulf war. The spike in ΣPCB concentrations during the war may be related to the destruction of PCB-laden transformers during the conflict. The 15-fold decrease in ΣPCB concentrations from the period of maximum flux to prewar levels suggests that the factors delivering PCBs to sediments at present are similar to those that that existed before the war-related inputs.  相似文献   
993.
Coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is one of the most contagious diseases in human history that has already affected millions of lives worldwide. To date, no vaccines or effective therapeutics have been discovered yet that may successfully treat COVID-19 patients or contain the transmission of the virus. Scientific communities across the globe responded rapidly and have been working relentlessly to develop drugs and vaccines, which may require considerable time. In this uncertainty, repurposing the existing antiviral drugs could be the best strategy to speed up the discovery of effective therapeutics against SARS-CoV-2. Moreover, drug repurposing may leave some vital information on druggable targets that could be capitalized in target-based drug discovery. Information on possible drug targets and the progress on therapeutic and vaccine development also needs to be updated. In this review, we revisited the druggable targets that may hold promise in the development of the anti-SARS-CoV-2 agent. Progresses on the development of potential therapeutics and vaccines that are under the preclinical studies and clinical trials have been highlighted. We anticipate that this review will provide valuable information that would help to accelerate the development of therapeutics and vaccines against SARS-CoV-2 infection.  相似文献   
994.
In situ fabrication of a sensitive electrochemical sensor using a wet-chemically prepared ternary ZnO/MgO/Cr2O3 nanofiber (NF)-decorated glassy carbon electrode (GCE) with Nafion adhesive was the approach of this study. The resultant NFs were characterized by various tools, such as powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area analysis, and ultraviolet–visible spectroscopy (UV/Vis). The analytical parameters of the proposed toluene sensor were characterized as follows: good sensitivity (23.89 μA μM−1 cm−2), a lower limit of detection (LOD; 95.59 ± 1.5 pM), a limit of quantification (LOQ; 318.63 ± 2.0 pM), efficient response time (18 s), and the dynamic range (LDR) for toluene detection of 0.1 nM–0.01 mM. The real-time application of the sensor is to protect the environmental ecosystem, as well as the public health from the harmful effects of toluene. In an environmental application, the toluene sensor exhibited good reproducibility, robustness, LOD, LOQ, and good reliability, which are discussed in detail and compared to the literature.

In situ fabrication of a sensitive electrochemical toluene sensor probe using wet-chemically prepared ternary ZnO/MgO/Cr2O3 nanofiber (NF)-decorated glassy carbon electrode (GCE) with Nafion adhesive was the approach of this study.  相似文献   
995.
A novel electrochemical (EC) chlorobenzene (CBZ) sensor was fabricated using a ternary oxide RuO2/ZnO/TiO2 nanocomposite (NC)-decorated glassy carbon electrode (GCE). The nanoparticles (NPs) were synthesized by a wet-chemical method and characterized by X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), and ultraviolet-visible (UV-vis) spectroscopy. The synthesized RuO2/ZnO/TiO2 NC was layered as thin film on a GCE with Nafion (5% suspension in ethanol) adhesive, and the as-prepared sensor was subjected to CBZ analysis using an electrochemical approach. The calibration of the proposed CBZ sensor was executed with a linear relation of current versus concentration of CBZs known as the calibration curve. The sensitivity (32.02 μA μM−1 cm−2) of the CBZ sensor was calculated from the slope of the calibration curve by considering the active surface area of the GCE (0.0316 cm2). The lower detection limit (LD; 98.70 ± 4.90 pM) was also calculated at a signal-to-noise ratio of 3. Besides these, the response current followed a linear relationship with the concentration of chlorobenzene and the linear dynamic range (LDR) was denoted in the range of 0.1 nM to 1.0 μM. Moreover, the CBZ sensor was found to exhibit good reproducibility, reliability, stability, and fast response time. Finally, the sensing mechanism was also discussed with the energy-band theory of ternary doped semiconductor materials. The sensing activity of the proposed sensor was significantly enhanced due to the combined result of depletion layer formation at the heterojunction of RuO2/ZnO/TiO2 NCs as well as the activity of RuO2 NPs as oxidation catalysts. The proposed CBZ sensor probe based on ternary oxide RuO2/ZnO/TiO2 NCs was developed with significant analytical parameters for practical application in monitoring the environmental pollutants of CBZs for the safety of environmental fields on a large scale.

A novel electrochemical (EC) chlorobenzene (CBZ) sensor was fabricated using a ternary oxide RuO2/ZnO/TiO2 nanocomposite (NC)-decorated glassy carbon electrode (GCE).  相似文献   
996.
997.

Background:

Many different systems are available for the treatment of fractures ranging from the heavy compression plates for mandibular reconstruction to low profile plates for mid-facial fixation, and are made either from stainless steel, titanium or vitallium. Recently, biodegradable, self-reinforced polylactide plates and screws have been used for the internal fixation of fractures of the mandible with good results.

Aim of this study:

This study evaluated clinically the biodegradable bone plates for treatment of mandibular body fracture and to evaluate bone healing during the follow-up period using digital radiography.

Materials and Methods:

Eight patients had been suffered from mandibular body fractures were treated using Inion CPSTM bioresorbable fixation system and the healing process were followed up using digitised panoramic radiography at first week and after 1, 3 and 6 months.

Results:

Clinical examination of fractured segments revealed stable fixation across the fracture sites while visual and quantitative assessment of radiograph showed healing process was comparable with results previously reported by titanium bone plates.

Conclusion:

Open reduction and internal fixation of mandibular fractures using bioresorbable fixation system with a brief period of inter-maxillary fixation have evolved to the point where the physical properties are sufficient to withstand the post-operative loads required for fracture repair of mandibular body fractures. The foreign body reaction is a major material-related problem which requires further studies.  相似文献   
998.
The development of posttraumatic stress disorder (PTSD) is influenced by genetic factors. Although there have been some replicated candidates, the identification of risk variants for PTSD has lagged behind genetic research of other psychiatric disorders such as schizophrenia, autism, and bipolar disorder. Psychiatric genetics has moved beyond examination of specific candidate genes in favor of the genome-wide association study (GWAS) strategy of very large numbers of samples, which allows for the discovery of previously unsuspected genes and molecular pathways. The successes of genetic studies of schizophrenia and bipolar disorder have been aided by the formation of a large-scale GWAS consortium: the Psychiatric Genomics Consortium (PGC). In contrast, only a handful of GWAS of PTSD have appeared in the literature to date. Here we describe the formation of a group dedicated to large-scale study of PTSD genetics: the PGC-PTSD. The PGC-PTSD faces challenges related to the contingency on trauma exposure and the large degree of ancestral genetic diversity within and across participating studies. Using the PGC analysis pipeline supplemented by analyses tailored to address these challenges, we anticipate that our first large-scale GWAS of PTSD will comprise over 10 000 cases and 30 000 trauma-exposed controls. Following in the footsteps of our PGC forerunners, this collaboration—of a scope that is unprecedented in the field of traumatic stress—will lead the search for replicable genetic associations and new insights into the biological underpinnings of PTSD.  相似文献   
999.
Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging viral pathogen that primarily causes respiratory illness. We conducted a seroprevalence study of banked human serum samples collected in 2012 from Southern Saudi Arabia. Sera from 300 animal workers (17% with daily camel exposure) and 50 non‐animal‐exposed controls were examined for serological evidence of MERS‐CoV infection by a pseudoparticle MERS‐CoV spike protein neutralization assay. None of the sera reproducibly neutralized the MERS‐CoV‐pseudotyped lentiviral vector. These data suggest that serological evidence of zoonotic transmission of MERS‐CoV was not common among animal workers in Southern Saudi Arabia during July 2012.  相似文献   
1000.

Objective

To determine the prevalence of overnutrition and undernutrition among neuropsychiatric inpatients and outpatients at Zomba Mental Hospital in Zomba, Malawi.

Methods

In this analytical cross-sectional study (n = 239), data were collected from psychiatric patients who were either inpatients (n = 181) or outpatients (n = 58) at Zomba Mental Hospital, which is the largest mental health facility in Malawi. Information was collected about patient demographics, anthropometric data, dietary information, and tobacco and alcohol use, among other variables. Data were entered and analysed in SPSS 16.0 (SPSS Inc., Chicago, IL, USA). Means were generated and compared between male and female patients, and between inpatients and outpatients.

Results

The study recruited 158 male and 81 female patients, with mean ages of 31.24 ± 11.85 years and 33.08 ± 15.18 years (p = 0.328), respectively. Male patients were significantly taller (165.27 ± 7.25 cm) than female patients (155.30 ± 6.56 cm) (p < 0.001); were significantly heavier than females (60.02 ± 10.56 kg versus 55.64 ± 10.53 kg); and had a significantly lower mean body mass index (BMI) than females (21.87 ± 3.21 vs. 23.01 ± 3.78) (p = 0.016). Overweight and obese patients comprised 17.6% of the participants, and 8.8% were underweight. There were no significant differences in the prevalence of overweight, obesity, and underweight between male and female participants, or between inpatients and outpatients.

Conclusion

Our study—the first one of its kind in Malawi—characterised the anthropometry of neuropsychiatric patients at a major metal health facility in Malawi, and has shown a high proportion of overweight patients and a notable presence of underweight patients among them. Being overweight or obese is a risk factor for metabolic disorders. Being underweight may aggravate mental illness or disturb the effect of medication. There is need, therefore, to include nutrition screening and therapeutic or supplementary feeding as part of a comprehensive care and treatment plan for neuropsychiatric patients.  相似文献   
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