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991.
Suhyun Lee 《RSC advances》2022,12(35):22911
This study attempted to develop a superhydrophobic conductive fabric to solve the problem of functional deterioration due to oxidation of conductive fabrics. To this end, a superhydrophobic surface was achieved by introducing nano-roughness to the surface of the polyester-conductive fabric by using alkaline hydrolysis, and then lowering the surface energy through hydrophobic coating. In order to derive optimal processing conditions with excellent superhydrophobicity while maintaining conductivity and mechanical properties, changes in surface structure, conductivity, superhydrophobicity and durability of conductivity against air and water were evaluated according to alkaline hydrolysis duration. As the alkaline hydrolysis duration increased, the polyester surface was etched and the silver oxide particles formed on the conductive yarns, creating non-uniform nano-roughness. The weight, tensile strength, and strain of the conductive fabric decreased due to alkaline hydrolysis, and the change was noticeable after 30 min of alkaline hydrolysis. In addition, as the alkaline hydrolysis duration increased, the surface resistance of the conductive fabric slightly increased and the surface temperature by electric heating performance decreased, but it still showed excellent conductivity. After 30 min of alkaline hydrolysis, a contact angle of more than 150° and a shedding angle of less than 10° achieved a superhydrophobic surface. This superhydrophobic surface prevented the reaction of silver with air or water in spite of prolonged exposure to air and repeated contact with water to maintain electrical properties, thereby improving the durability of conductivity. This study is significant in that it achieved dual roughness for superhydrophobicity on the surface of conductive fabrics using a relatively easy and simple method by applying alkaline hydrolysis, which is commonly used with polyester fabric. Therefore, it is expected to solve the problem of conductivity loss of the use of conductive fabric in various environments.

A superhydrophobic conductive fabric is developed to solve the problem of functional deterioration due to oxidation by air and water through alkaline hydrolysis and hydrophobic coating.  相似文献   
992.
993.
ObjectivesThis study evaluated the response in Daegu, Korea to the first wave of the coronavirus disease 2019 (COVID-19) pandemic according to a public health emergency response model.MethodsAfter an examination of the official data reported by the city of Daegu and the Korea Centers for Disease Control and Prevention, as well as a literature review and advisory meetings, we chose a response model. Daegu’s responses were organized into 4 phases and evaluated by applying the response model.ResultsIn phase 1, efforts were made to block further transmission of the virus through preemptive testing of a religious group. In phase 2, efforts were concentrated on responding to mass infections in high-risk facilities. Phase 3 involved a transition from a high-intensity social distancing campaign to a citizen participation–based quarantine system. The evaluation using the response model revealed insufficient systematic preparation for a medical surge. In addition, an incorporated health-related management system and protection measures for responders were absent. Nevertheless, the city encouraged the participation of private hospitals and developed a severity classification system. Citizens also played active roles in the pandemic response by practicing social distancing.ConclusionsThis study employed the response model to evaluate the early response in Daegu to the COVID-19 pandemic and revealed areas in need of improvement or maintenance. Based on the study results, creation of a systematic model is necessary to prepare for and respond to future public health emergencies like the COVID-19 pandemic.  相似文献   
994.
995.
PURPOSE: To describe the clinic-pathological analysis of the visually significant opacification of the Cirrus International Hydroflex foldable hydrophilic acrylic intraocular lens (IOL) (model SC600-2, Medical Developmental Research Inc., Clearwater, Florida) and to highlight that this IOL is the same model as the Acryflex SC600-2 IOL, by the same manufacturer. METHODS: Retrospective review of five eyes of four patients with opacification of their Cirrus International Hydroflex foldable hydrophilic acrylic IOLs (model SC600-2) after uncomplicated phacoemulsification and IOL implantation. Two IOLs were explanted from two patients 14 to 24 months after initial implantation. Each explanted lens was divided into equal halves, one half for scanning electron microscopy (SEM) study and the other half for transmission electron microscopy (TEM) examination. SEM and TEM samples were also subjected to energy dispersive X-ray analysis (EDX). RESULTS: The IOL opacification was detected 14 to 24 months after uncomplicated phacoemulsification and IOL implantation. EDX analysis showed that the crystals contained calcium and phosphorus, presumably calcium phosphate. CONCLUSIONS: The Cirrus International Hydroflex foldable hydrophilic acrylic IOL (model SC600-2) is associated with opacification, that appeared worse centrally than peripherally. This is the same model as the Acryflex SC600-2 IOL, made by the same manufacturer. The opacification consists of calcium and phosphate.  相似文献   
996.
997.
An orbital embryonal rhabdomyosarcoma, which was excised from the orbit of an 8-year-old girl, was studied by light microscopy and transmission electron microscopy. Cells within the tumour demonstrated by light microscopy diffuse areas of necrosis and isolated single-cell necrosis. There were many viable tumour cells with intracytoplasmic vacuolar structures which contained basophilic granules. Ultrastructural studies showed close apposition between well-preserved tumour rhabdomyoblasts and degenerate or necrotic tumour cells: degenerate cells and condensed cell fragments were observed within the cytoplasm of the well-preserved tumour cells. Some cells which showed degenerative changes had features which suggested that they had ingested more than one degenerate cell on separate occasions. This phenomenon may be regarded as a variant of selective individual cell death, currently referred to as apoptosis, which has not been previously reported in a case of embryonal rhabdomyosarcoma. The patient remains free of tumour recurrence four years following treatment with combined radiotherapy and chemotherapy.  相似文献   
998.
Fine-needle aspiration of the breast has become a well-accepted diagnostic tool for the management of breast lesions. When employed on an ambulatory basis it is both accurate and cost-effective. This study of a series of patients managed over a 2-year period demonstrates the use of this technique in an ambulatory gynecologic practice. Results demonstrate this to be a very rapidly accomplished, effective procedure that is very well accepted by the patients. Results are generally available within 24 hours and permit both the physician and the patient to accurately predict the course of management. In addition, it allows the primary physician to accurately determine which patients will require in-hospital management and which may safely undergo ambulatory, office-based biopsy of solid lesions. Experience shows this to be a valuable diagnostic tool that can be safely utilized by the practicing gynecologist.  相似文献   
999.
Seven oliguric women with preeclampsia were identified among patients admitted for obstetric care at Jefferson Davis or Hermann Hospitals in Houston, Texas. Urinary diagnostic indices (including urine-to-plasma ratios of creatinine, urea nitrogen, and osmolality) were generally consistent with a prerenal etiology for the observed oliguria. Conversely, invasive hemodynamic monitoring revealed a volume replete state in five of seven preeclamptic women studied. All patients were observed to have markedly elevated urinary sodium concentrations. The transient oliguria observed in these patients spontaneously resolved without diuretic or hyperosmolar agents. We conclude that oliguria is a poor index of volume status in preeclamptic women. Urinary diagnostic indices may also be misleading if used to guide fluid management in these patients. Finally, the clinical significance and therapeutic alternatives relating to preeclampsia-associated oliguria are discussed.  相似文献   
1000.
Natural killer (NK) cells have the ability to kill a variety of target cell types and the possibility that such cells could mount an effective attack on the developing fetus has not been discounted. The present study extends previous work showing that maternal NK reactivity against K562 target cells (TC) is reduced during pregnancy. Here we demonstrate using cytotoxicity assays at both the population and single cell level that, although depressed in number, maternal NK cells exhibiting the capacity to kill K562 TC are as lytically active in their ability to recycle and destroy multiple TC as NK cells from non-pregnant females. Moreover, two colour immunofluorescence analysis of the NK cell-associated markers Leu-7 and Leu-11b indicates that, in addition to a reduction in the absolute number of TC conjugate-forming cells, pregnant females present in their peripheral blood a larger proportion of TC-binding Leu-7+11- cells. These cells may be lytically immature. Small changes in NK cell profile and activity in maternal peripheral blood may be indicative of much more significant changes at the feto-maternal interface. It is, however, clear that pregnant females retain a population of highly active NK cells, thus minimising the possibility of immunocompromise.  相似文献   
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