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41.
The genetic background predisposing pregnant women to pre-eclampsia/eclampsia (PE/E) is still unknown. The aim of the current study was to investigate whether there is an association between the TNF-alpha-308 and 850 polymorphisms and PE or eclampsia. In this study, 40 cases of eclampsia, 113 cases of PE and 80 normotensive control cases were genotyped for the TNF-alpha-G-308A and C-850 polymorphisms. At position 308, the replacement of Guanine with Adenosine was denoted as TNF2. We found a significant difference between the TNF2 allele frequencies of the eclamptic, pre-eclamptic and normotensive controls. TNF2 (AA) polymorphism frequency was significantly higher among the eclamptics and pre-eclamptics (control : 5%, PE : 13.3%, E : 12.9%). A significantly different genotype distribution of C-850T polymorphism was observed between the PE/E and control groups, with the frequency of the variant TT genotype being significantly reduced in the preeclamptics (PE : 17% ; E : 17.5%) when compared with the control group (24.3%). We have demonstrated an association between TNF-alpha polymorphisms and pre-eclampsia susceptibility. However, it is not known whether C-850T polymorphism has a functional effect on the TNF-alpha gene. In addition, it was not possible to determine whether this polymorphism promotes the progression from PE to eclampsia because of no statistically significant difference between eclampsia and the controls.  相似文献   
42.
Objectives. Vitamin D regulates calcium and bone homeostasis, and parathyroid hormone (PTH) secretion. Cross-sectional associations between lower vitamin D levels and cardiovascular diseases have been reported, but the relationship between vitamin D levels and collateral arteries in stable coronary artery disease (CAD) has not been reported before. Design. Two hundred and fourteen patients with above 95% stenosis in at least one epicardial coronary artery were consecutively recruited after coronary angiography (CAG) during the winter season. The coronary collateral circulation (CCC) was graded using Rentrop classification. Poor CCC group included patients with Rentrop Grade 0–1 CCC and control group included patients with Rentrop Grade 2–3 CCC. Vitamin D and PTH levels were measured on the day of CAG. Results. In the poor CCC group, vitamin D levels were lower (34 ± 25 pmol/L vs. 49 ± 33 pmol/L; p = 0.01) and the prevalence of vitamin D deficiency (< 37 pmol/L) was higher (67% vs. 43%; p = 0.01) compared to the controls. PTH levels, calcium, and phosphate levels were not significantly different between the groups. Female gender, lower HDL cholesterol, and lower vitamin D levels were independently correlated with poor CCC in the study population. Conclusion. Lower vitamin D levels may be associated with poor collateral development in patients with stable CAD.  相似文献   
43.
In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu3+:YPO4 and different phases (hexagonal + tetragonal and pure tetragonal) of Pr3+:YPO4 crystals. We report variation of fine structure energy levels in different doped ions (Eu3+ and Pr3+) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr3+:YPO4.

By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal.  相似文献   
44.
ObjectiveTo assess the effects of dextrose prolotherapy in patients with knee osteoarthritis on the levels of serum cartilage oligomeric proteinase and urinary C-terminal telopeptide of type II collagen, and on the Western Ontario McMaster Universities Index and numerical rating scale score for pain.MethodsA randomized controlled trial, in which participants were randomly allocated into 2 groups, receiving injections of either hyaluronic acid or dextrose prolotherapy. The hyaluronic acid group received 5 injections, 1 each on weeks 1, 2, 3, 4 and 5, and the dextrose prolotherapy group received 3 injections, 1 each on weeks 1, 5 and 9. Serum cartilage oligomeric proteinase, urinary C-terminal telopeptide of type II collagen, Western Ontario McMaster Universities Index score, and numerical rating scale score for pain were measured at baseline and 3 weeks after the last injection. Comparative analysis was conducted using Wilcoxon test within groups and analysis of covariance (ANCOVA) test between groups.ResultsA total of 47 participants (21 allocated to hyaluronic acid, 26 allocated to dextrose prolotherapy) completed the protocol. Both interventions resulted in significant improvements in numerical rating scale scores for pain, total Western Ontario McMaster Universities Index scores, and its subscales score. However, the dextrose prolotherapy outperformed hyaluronic acid in numerical rating scale score for pain and level of urinary C-terminal telopeptide of type II collagen, with score changes differences of 0.93 (p = 0.042) and 0.34 (p = 0.048), respectively. No significant changes in level of serum cartilage oligomeric proteinase were found in either group.ConclusionDextrose prolotherapy is an alternative injection therapy for knee osteoarthritis, which was found to be associated with a significant reduction in urinary C-terminal telopeptide of type II collagen compared with hyaluronic acid injection. Neither injection method resulted in reduced serum cartilage oligomeric proteinase.LAY ABSTRACTKnee osteoarthritis is a common musculoskeletal disorder, which is one of the most frequent causes of disability in elderly people. To improve patients’ quality of life, prolotherapy has been developed as a non-operative treatment option for osteoarthritis. This study compared the effectiveness of dextrose prolotherapy with that of standard therapy using hyaluronic acid injections. Both interventions were effective in terms of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score improvement and numerical rating scale score changes. Cartilage repair was assessed by measuring levels of specific biomarkers of cartilage breakdown: urinary C-terminal telopeptide of type II collagen (uCTX-II) and serum cartilage oligomeric matrix protein (sCOMP). Dextrose prolotherapy was more effective than hyaluronic acid in reducing these biomarkers and decreasing patients’ pain. Dextrose prolotherapy is therefore recommended for use in patients with knee osteoarthritis, since it gives better results, is cost beneficial, and is suitable for use in low-resource settings. Dextrose prolotherapy may help to repair cartilage in knee OA, as it reduces the uCTX-II level.Key words: knee osteoarthritis, prolotherapy, hyaluronic acid, COMP, uCTX-II, functional outcome

Osteoarthritis (OA) is a highly prevalent musculoskeletal disorder, which is one of the most common causes of disability in elderly people (13). Several studies have demonstrated the effectiveness of hyaluronic acid (HA) injections, and recent guidelines have recommended their use in knee OA (4, 5). Xin has shown that intra-articular injection of HA (Adant®, Meiji Seika Pharma Co., Ltd., Tokyo, Japan. Manufactured by microbial fermentation and Artz®, Dispo: Seikagaku Corporation, Tokyo, Japan. Manufactured by the extraction of cockscomb), can significantly reduce both the visual analogue scale (VAS) score for pain and the Lequesne index (6). In contrast to these findings, however, a meta-analysis concluded that treatment of knee OA with HA injection did not result in a significantly different outcome from intra-articular placebo, despite the higher costs compared with other common non-operative intra-articular modalities (7).Regenerative therapy is an alternative approach that has been considered for OA, due to its potential to aid tissue regeneration, improve clinical manifestations, and repair damaged tissue structure, which is the underlying pathological condition in OA (8). An example of a currently developing regenerative approach is prolotherapy, an injection-based modality for treating chronic musculoskeletal pain through the use of substances such as dextrose, phenol-glycerine-glucose (P2G), or sodium morrhuate (9). Previous reports have demonstrated the effectivity of prolotherapy in significantly reducing the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score relative to saline injections and at-home exercise over 18 weeks after injection (1012). In line with these findings, other reports have shown the promising effects of prolotherapy for tissue regeneration through radiological and arthroscopy-based assessments of cartilage repair (13).Cartilage oligomeric matrix protein (COMP) and urinary C-terminal telopeptide of type II collagen (uCTX-II) are specific biomarkers used to evaluate cartilage break-down in OA. Increased levels of these biomarkers can indicate the severity and prognosis of OA(14). Meanwhile, decrease in levels of both biomarkers has been assumed which indicates the improvement in cartilage (15). COMP and uCTX-II are recommended as promising specific bio-markers in OAcases based on Burden of disease, Investigative, prognostic, efficacy of intervention, and diagnostic (BIPED) criteria, as stated in a systematic review (16).Although previous reports have demonstrated promising potential of HA-based therapy and dextrose prolotherapy (DPT) in improving functional outcome in knee OA, none have compared the efficacy of those modalities in cartilage repair by assessing specific biomarkers, such as serum COMP (sCOMP) and uCTX-II. Hence, the aim of this study was to compare the effects of intra-articular HAand DPT on cartilage repair in knee OA, by measuring the changes in sCOMP and uCTX-II biomarkers.  相似文献   
45.
46.
The United Arab Emirates (UAE) has undergone a significant change in its population and economy in the last decades and in parallel its healthcare system has evolved rapidly to provide advanced, innovative and world-leading care. At the forefront of this revolution in healthcare is the development of a multidisciplinary multimodality thoracic service provision, offered at quaternary referral hospitals amalgamating academics, training, research and innovation. Previously, thoracic service care was limited to single providers at various public and private hospitals, usually performing lower complexity cases. Most complex thoracic cases were repatriated outside the UAE. This practice was replaced with the opening of Cleveland Clinic Abu Dhabi (CCAD), in 2015, which created a multidisciplinary thoracic program. This included the start of a mini-invasive surgical and lung transplantation program. Since that time other public and private hospitals have emerged providing care in a similar model. The impact of these programs has been a decreased transfer of patients abroad for treatment. Under the umbrella of the Emirates Thoracic Society (ETS) a platform for greater collaboration aimed at improving patient care, potential research and physician education has been created. Direct links have been established with world-leading Thoracic surgery and Respiratory Medicine Centers facilitating this development and offering support and guidance. This article charts these changes in thoracic care in the recent past, present, and delineates plans for the future in the UAE.  相似文献   
47.
In this study, compacted hematite (Fe2O3) preforms were made and sintered at various temperatures, such as 1250 °C and 1300 °C, using both conventional and microwave sintering methods. The density, porosity, microhardness, cold crushing strength, microphotographs, and X-ray diffraction (XRD) analysis of the sintered preforms were used to evaluate the performance of the two sintering methods. It was found that microwave sintered preforms possessed lesser porosity and higher density than conventionally sintered preforms owing to uniform heating of the powdered ore in microwave sintering method. Furthermore, it was also observed that microwave sintered preforms exhibited relatively higher cold crushing strength and hardness than conventionally sintered preforms. Thus, the overall results revealed that microwave sintering yielded better properties considered in the present study.  相似文献   
48.
Cracks in typical mortar constructions enhance water permeability and degrade ions into the structure, resulting in decreased mortar durability and strength. In this study, mortar samples are created that self-healed their cracks by precipitating calcium carbonate into them. Bacillus subtilus bacterium (10−7, 10−9 cells/mL), calcium lactate, fine aggregate, OPC-cement, water, and bagasse ash were used to make self-healing mortar samples. Calcium lactates were prepared from discarded eggshells and lactic acid to reduce the cost of self-healing mortars, and 5% control burnt bagasse ash was also employed as an OPC-cement alternative. In the presence of moisture, the bacterial spores in mortars become active and begin to feed the nutrient (calcium lactate). The calcium carbonate precipitates and plugs the fracture. Our experimental results demonstrated that cracks in self-healing mortars containing bagasse ash were largely healed after 3 days of curing, but this did not occur in conventional mortar samples. Cracks up to 0.6 mm in self-healing mortars were filled with calcite using 10−7 and 10−9 cell/mL bacteria concentrations. Images from an optical microscope, X-ray Diffraction (XRD), and a scanning electron microscope (SEM) were used to confirm the production of calcite in fractures. Furthermore, throughout the pre- and post-crack-development stages, self-healing mortars have higher compressive strength than conventional mortars. The precipitated calcium carbonates were primed to compact the samples by filling the void spaces in hardened mortar samples. When fissures developed in hardened mortars, bacteria became active in the presence of moisture, causing calcite to precipitate and fill the cracks. The compressive strength and flexural strength of self-healing mortar samples are higher than conventional mortars before cracks develop in the samples. After the healing process of the broken mortar parts (due to cracking), self-healing mortars containing 5% bagasse ash withstand a certain load and have greater flexural strength (100 kPa) than conventional mortars (zero kPa) at 28 days of cure. Self-healing mortars absorb less water than typical mortar samples. Mortar samples containing 10−7 bacteria cells/mL exhibit greater compressive strength, flexural strength, and self-healing ability. XRD and SEM were used to analyze mortar samples with healed fractures. XRD, FTIR, and SEM images were also used to validate the produced calcium lactate. Furthermore, the durability of mortars was evaluated using DTA-TGA analysis and water absorption tests.  相似文献   
49.
Membrane fouling is a major hindrance to widespread wastewater treatment applications. This study optimizes operating parameters in membrane rotating biological contactors (MRBC) for maximized membrane fouling through Response Surface Methodology (RSM) and an Artificial Neural Network (ANN). MRBC is an integrated system, embracing membrane filtration and conventional rotating biological contactor in one individual bioreactor. The filtration performance was optimized by exploiting the three parameters of disk rotational speed, membrane-to-disk gap, and organic loading rate. The results showed that both the RSM and ANN models were in good agreement with the experimental data and the modelled equation. The overall R2 value was 0.9982 for the proposed network using ANN, higher than the RSM value (0.9762). The RSM model demonstrated the optimum operating parameter values of a 44 rpm disk rotational speed, a 1.07 membrane-to-disk gap, and a 10.2 g COD/m2 d organic loading rate. The optimization of process parameters can eliminate unnecessary steps and automate steps in the process to save time, reduce errors and avoid duplicate work. This work demonstrates the effective use of statistical modeling to enhance MRBC system performance to obtain a sustainable and energy-efficient treatment process to prevent human health and the environment.  相似文献   
50.
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