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991.
The severely of skin loss and the options of resurfacing is determined by taking into account the following factors. 1) The size & location of the defect, 2) The depth of the defect and the quality of the tissue bed, 3) The extent of exposed vital structures, 4) The associated bone and other tissues injuries, 5) The availability of donor skin flap. The size of the defect is the most important factor in choosing a resurfacing option. The size can be categorized into small, medium and large. A small defect is one that is less than 5 cm2 in size, a medium defect is between 5 to 15 cm2, and a large defect is greater than 15 cm2. Local flaps are usually sufficient to cover small defects <5 cm2. These are advancement flaps or rotation and transposition flaps. Regional flaps are indicated to resurface these medium‐sized defects 5 to 15 cm2. The donor is within the same region of the hand, from one of the digits or from dorsum and palmar surfaces of the hand. It is usually based on vascular or NV pedicles. Large defects >15 cm2 will need larger flaps for coverage. These large flaps are pedicled distant flaps and free flaps. In these severe injuries, there is usually associated bone and soft tissues injuries. These injuries can be reconstructed as a single stage combined reconstruction or multi‐staged reconstructions. The resurfacing should always be given priority.  相似文献   
992.
Obesity related cardiovascular disease has assumed epidemic proportions and it is important that we properly understand how hormones of metabolism influence cardiac function. Over the last 15 years a multitude of factors have been discovered that appear to play significant roles in energy balance and metabolism, markedly changing our view of fat and GI cells and their dynamic control and regulation of metabolism. This presentation will focus on how three recently discovered hormones Ghrelin, Leptin and Resistin may directly influence cardiac function. Ghrelin is predominately produced and secreted from the X/A cells of the stomach and studies suggest it can act as a cardioprotective agent. However, Ghrelin also acts to constrict the coronary arteries, which places potential limitations upon its therapeutic use. Leptin is produced by adipose tissue in proportion to fat deposition and appears to drive satiety signals in the body. In contrast, Leptin appears to antagonise cardiac function and it may drive the development of hypertension by impairing renal pressure natriuresis and down regulating endothelium derived vasorelaxant factors. The third factor, Resistin, was originally described from rat adipose tissue and was shown to impair insulin action and glucose control. In humans however, Resistin is primarily produced in inflammatory cells such as monocytes and macrophages. Resistin worsens the recovery of the heart from a period of experimental ischemia and promotes the release of inflammatory agents such as tumour necrosis factor‐alpha. Such actions may be partially responsible for the observed insulin resistance after cardiac surgery.  相似文献   
993.
In Australia there is currently no consistent approach to collecting breast cancer specific data. The National Health Data Dictionary (NHDD) recommends a core set of generic data items for clinical cancer registration. However this list does not include the more detailed items required by specific tumour streams. The NBCC has developed a supplementary set of Breast Specific Data Items and definitions to serve as a guide for specialist breast cancer data collection in Australia. A multidisciplinary Working Group comprising clinical and consumer representation, including three breast surgeons, identified 16 breast specific data items for collection. The items are designed to align with items collected through the RACS National Breast Cancer Audit and leading cancer centres. A range of items from patient data (menopausal status), diagnostic data (HER2 status, sentinel lymph node), treatment (surgical margin clearance and involvement), and breast reconstruction are included. The data items are recommended as best practice for breast cancer specific data collection and aim to facilitate national consistency in defining, recording, and monitoring information about patients with breast cancer. This national approach will contribute to improved patient outcomes by informing planning, quality improvement and evaluation strategies for cancer services. The items are currently being piloted in two sites in NSW and will be available nationally in late 2007.  相似文献   
994.
BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated.  相似文献   
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There are at least two reasons why this Oxford handbook meritsa review in the British Journal of Anaesthesia. A proportionof readers will be involved at some time during their careerin the provision of pre-hospital care and most of us will onoccasion manage patients on their arrival in hospital followingcare for acute medical and surgical problems in the community.The Oxford series aims to act as a succinct primer in each subject,and this one succeeds. The contents page illustrates its  相似文献   
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999.
Mesenchymal stem cells (MSC), easily culture-expanded from bone marrow, can significantly enhance bone defect healing. Several proteins, such as the bone morphogenetic proteins (BMPs) and in particular BMP-7, are involved in bone formation in vitro and in vivo. In this preclinical study, we evaluated if the association of human MSC (hMSC) with BMP-7 had synergic action on bone healing. Rat femoral defects (n=12) were treated with: autoclaved bone and mononucleated cells (MNC) as control group G1; bone and hMSC, group G2; bone with BMP-7, group G3; bone and hMSC plus BMP-7, group G4. Defect regeneration was evaluated with plain radiographs after 2, 4, 8 and 12 weeks and with histological analysis. We observed organized trabeculae bridging between the osteotomic ends of the host bone in rats treated with the association of hMSC and rhBMP-7. These trabeculae, formed by a core of devitalized tissue surrounded by osteoblasts, osteocytes and osteoclasts, were continuous with a cortical-like structure of bony tissue. Such new bone formation of the group treated with the association of hMSC and rhBMP-7 (G4) was clearly superior compared to rats treated with rhBMP-7 (G2) or hMSC (G3) alone, as shown by radiographic analysis and histological study. The present study suggests that the association of hMSC and BMP-7 is more effective than hMSC or BMP-7 alone in the healing of femoral defects in rats. Further studies with larger samples are required to confirm these results and to evaluate the best dosage.  相似文献   
1000.
The objective of this study was to investigate the effect of fluoridated elastomeric ligatures on the microbiology of local dental plaque in vivo. This randomized, prospective, longitudinal, clinical trial had a split-mouth crossover design. The subjects were 30 patients at the beginning of their treatment with fixed orthodontic appliances in the orthodontic departments of the Liverpool and the Sheffield dental hospitals in the United Kingdom. The study consisted of 2 experimental periods of 6 weeks with a washout period between. Fluoridated elastomers were randomly allocated at the first visit to be placed around brackets on tooth numbers 12, 11, 33 or 22, 21, 43. Nonfluoridated elastomers were placed on the contralateral teeth. Standard nonantibacterial fluoridated toothpaste and mouthwash were supplied. After 6 weeks (visit 2), the elastomers were removed, placed in transport media, and plated on agar within 2 hours. Nonfluoridated elastomers were placed on all brackets for 1 visit to allow for a washout period. At visit 3, fluoridated elastomers were placed on the teeth contralateral to those that received them at visit 1. At visit 4, the procedures at visit 2 were repeated. Samples were collected on visits 2 and 4. A logistic regression was performed, with the presence or absence of streptococcal or anaerobic growth as the dependent variable. A mixed-effects analysis of variance was carried out with the percentage of streptococcal or anaerobic bacterial count as the dependent variable. The only significant independent variables were the subject variable (P =<.001) for the percentage of streptococcal and anaerobic bacterial count and the visit variable for the percentage of streptococcal count (P =<.001). The use of fluoridated or nonfluoridated elastomers was not significant for percentage of either streptococcal (P =.288) or anaerobic count (P =.230). Fluoridated elastomers are not effective at reducing local streptococcal or anaerobic bacterial growth after a clinically relevant time in the mouth.  相似文献   
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