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21.
Purpose Adjuvant therapy for Stage II colon cancer remains controversial but may be considered for patients with high-risk features. The purpose of this study was to assess the prognostic significance of commonly reported clinicopathologic features of Stage II colon cancer to identify high-risk patients. Methods We analyzed a prospectively maintained database of patients with colon cancer who underwent surgical treatment from 1990 to 2001 at a single specialty center. We identified 448 patients with Stage II colon cancer who had been treated by curative resection alone, without postoperative chemotherapy. Results With median follow-up of 53 months, 5-year disease-specific survival for this cohort was 91 percent. Univariate and multivariate analyses identified three independent features that significantly affected disease-specific survival: tumor Stage T4 (hazard ratio (HR), 2.7; 95 percent confidence interval (CI), 1.1–6.2; P = 0.02), preoperative carcinoembryonic antigen >5 ng/ml (HR, 2.1; 95 percent CI, 1.1–4.1; P = 0.02), and presence of lymphovascular or perineural invasion (HR, 2.1; 95 percent CI, 1–4.4; P = 0.04). Five-year disease-specific survival for patients without any of the above poor prognostic features was 95 percent; five-year disease-specific survival for patients with one of these poor prognostic features was 85 percent; and five-year disease-specific survival for patients with ≥2 poor prognostic features was 57 percent. Conclusions Patients with Stage II colon cancer generally have an excellent prognosis. However, the presence of multiple adverse prognostic factors identifies a high-risk subgroup. Use of commonly reported clinicopathologic features accurately stratifies Stage II colon cancer by disease-specific survival. Those identified as high-risk patients can be considered for adjuvant chemotherapy and/or enrollment in investigational trials. Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, June 2 to 6, 2007. Reprints are not avaliable.  相似文献   
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Fatty liver can present as focal, diffuse, heterogeneous, and multinodular forms. Being familiar with various patterns of steatosis can enable correct diagnosis. In patients with equivocal findings on ultrasonography, magnetic resonance imaging can be used as a problem solving tool. New techniques are promising for diagnosis and follow-up. We review imaging patterns of steatosis and new quantitative methods such as proton density fat fraction and magnetic resonance elastography for diagnosis of nonalcoholic fatty liver disease in children.Nonalcoholic fatty liver disease (NAFLD) is as widely encountered in children as in adults, with an estimated prevalence of 9.6% (1). It occurs due to accumulation of triglyceride in hepatocytes without alcohol ingestion. Nonalcoholic steatohepatitis (NASH) was first defined in children in 1983 (2). NAFLD includes a broad range of clinicopathologic features ranging from simple steatosis (fat with inflammation and/or fibrosis), steatohepatitis/NASH to cirrhosis. Some other diseases of liver can also cause hepatic steatosis including hepatitis B and C, Wilson’s disease, α-1-antitrypsin deficiency, autoimmune hepatitis, drug-induced liver injury (valproate, methotrexate, tetracycline, amiodarone, and prednisone), and total parenteral nutrition (3). Furthermore, fatty liver is a risk factor for cirrhosis, diabetes, and cardiovascular disease.In clinical practice, the diagnosis of NAFLD is made by increased serum ALT and/or presence of enlarged echogenic liver in ultrasonography. Being overweight or obese, and/or insulin resistance are highly indicative but not absolutely necessary for diagnosing NAFLD (4). The gold standard for diagnosis is liver biopsy, which additionally provides semi-quantitative analysis of NASH damage in children (5). It is an expensive, invasive procedure with a risk of morbidity (0.06%–0.35%) and mortality (0.01%–0.1%) (6).The evaluation of liver fat in children via noninvasive imaging modalities is needed to avoid complications of biopsy and for follow-up. Main imaging modalities for the assessment of pediatric NAFLD are ultrasonography (US) and magnetic resonance imaging (MRI). Computed tomography is the other imaging method for liver fat assessment, but ionizing radiation is a major drawback in children (7). Assessment of fat accumulation may cause diagnostic dilemmas and confusion due to manifestations with unusual structural patterns and imaging appearance of the liver. This article reviews the histopathology of pediatric NAFLD, radiologic evaluation and different structural patterns of childhood NAFLD/NASH on US and MRI. We also discuss diagnostic pitfalls and briefly review new imaging techniques.  相似文献   
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This study was conducted to evaluate the efficacy of high-dose thiotepa, melphalan and carboplatin (TMCb) regimen in 27 patients undergoing autologous stem cell transplantation (ASCT) for metastatic breast cancer. A total of 27 patients with stage IV breast cancer underwent ASCT following thiotepa (500 mg/m(2)), melphalan (100 mg/m(2)) and carboplatin (1200-1350 mg/m(2)). Of 27 patients, 17 had refractory relapse, eight had responding relapse, and two had no evidence of disease (NED) at the time of transplant. In all, 11 patients had only bone disease, nine had bone plus visceral disease, three had only visceral disease, and two had locoregional recurrent disease. The median time from diagnosis to transplant was 1081 days (range 180-2341). Staging for evaluation of response was performed 4-6 months after transplantation. Five patients were not evaluable (NE) for response because of NED at transplant (n=2) or early death due to transplant-related complications (n=3) (two of viral pneumonia and one of regimen-related toxicity) occurring at a median of 4 days (range 11-46) post-transplant. One of the two patients who was NED at the time of transplant is still NED on day 760 post-transplant. Seven of 15 refractory (47%) and 5/7 (71%) responsive patients with evaluable disease achieved a complete response of all measurable disease or all soft-tissue disease with at least improvement in bone lesions. Of 27 patients (37%),(10) are alive and progression-free, a median of 582 days (range 410-1380) after treatment, 6/17 (35%) with refractory disease and 4/10 (40%) with responsive disease. The probability of progression-free survival (PFS) for all patients was 0.50. The probabilities of PFS at 2 years for patients with refractory (n=17) and responsive (n=10) disease were 0.42 and 0.60, respectively. PFS at 2 years for the 14 patients who were NED or achieved CR/PR(*) following-HDC was 0.67. PFS at 2 years for patients who did not achieve CR/PR(*) following-DHC was 0.33. These preliminary data suggest that high-dose TMCb followed by autologous stem cell transplantation is an effective regimen for patients with advanced breast cancer and may be comparable to some previously used regimens.  相似文献   
24.
Leukemia stem cells (LSCs) are found in most aggressive myeloid diseases and contribute to therapeutic resistance. Leukemia cells exhibit a dysregulated developmental program as the result of genetic and epigenetic alterations. Overexpression of the RNA-binding protein Musashi2 (MSI2) has been previously shown to predict poor survival in leukemia. Here, we demonstrated that conditional deletion of Msi2 in the hematopoietic compartment results in delayed leukemogenesis, reduced disease burden, and a loss of LSC function in a murine leukemia model. Gene expression profiling of these Msi2-deficient animals revealed a loss of the hematopoietic/leukemic stem cell self-renewal program and an increase in the differentiation program. In acute myeloid leukemia patients, the presence of a gene signature that was similar to that observed in Msi2-deficent murine LSCs correlated with improved survival. We determined that MSI2 directly maintains the mixed-lineage leukemia (MLL) self-renewal program by interacting with and retaining efficient translation of Hoxa9, Myc, and Ikzf2 mRNAs. Moreover, depletion of MLL target Ikzf2 in LSCs reduced colony formation, decreased proliferation, and increased apoptosis. Our data provide evidence that MSI2 controls efficient translation of the oncogenic LSC self-renewal program and suggest MSI2 as a potential therapeutic target for myeloid leukemia.  相似文献   
25.
Autoimmune polyglandular syndrome (APS) is a disorder which is associated with multiple endocrine gland insufficiency and also with non-endocrine manifestations. The pathophysiology of APS is poorly understood, but the hallmark evidence of APS is development of autoantibodies against multiple endocrine and non-endocrine organs. These autoantibodies are responsible for the dysfunction of the affected organs and sometimes may also cause non-endocrine organ dysfunction. The hemolytic-uremic syndrome (HUS) is a serious and life-threatening disease which develops due to many etiological factors including autoimmune disorders. Here, we present an unusual case of APS. Ectodermal dysplasia with immune deficiency and HUS occurred concomitantly in the same patient with APS type 3c. Once the autoantibody generation was initiated in the human body, development of multiple disorders due to organ dysfunction and also autoantibody-related diseases may have occurred.  相似文献   
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Editorial     
It has been proven that the jaw rehabilitation not only has a crucial role in treatment of both trismus and mandibular hypomobility but also in the rehabilitation of surgical conditions of the temporomandibular joint and the jaw.(1) Today, the commercially available jaw motion rehabilitation systems are specifically designed to treat these conditions.(2) These systems utilize repetitive passive motion and stretching to restore mobility and flexibility of the jaw musculature, associated joints and connective tissues. Major advantages of these systems are that they reduce patients' anxiety by allowing them to control the extent and length of each stretching and provide passive motion for effective jaw rehabilitation therapy allowing patients to perform their necessary therapy while continuing in their daily life.(3) However, these systems are very expensive and mostly unavailable in our country. So, a new alternative jaw motion rehabilitation device 'The Okbite' was developed recently in our hospital (Fig. 1). It is simply adapted from the commercially available nasal specula. The blades of the specula are cut distally and metal bite pads are attached to these sites. The lower bite pad was placed posteriorly and curved anatomically. This device can be produced in a custom-made form according the occlusal pattern and the size of the mandible of the patient. The metal bite pads are covered with plaster bandage by the patient for a soft bite. In our practice, we used this device for the rehabilitation of total temporomandibular joint prosthesis, temporomandibular gap arthroplasties and temporomandibular joint disorders with great success. It costs nearly 1/50 of the commercially available jaw motion rehabilitation systems with almost equal outcomes of pain relief and total mouth opening. The major disadvantage of this system is that it can mimic the anatomical motion pattern of the mandible to a limited extend. We propose the application of this Okbite system, which provides jaw rehabilitation in such conditions.  相似文献   
28.
Aspiration is a serious complication of gastrointestinal (GI) decontamination procedure. Studies have shown that tumor necrosis factor-α (TNF-α) blockers have beneficial effects on lung injury. Therefore, the authors investigated the attenuation by infliximab (INF) on activated charcoal (AC)- and polyethylene glycol (PEG)-induced lung injury in rat model. Forty-two male Sprague-Dawley rats were allotted into 1 of 6 groups: saline (NS), activated charcoal (AC), polyethylene glycol (PEG), NS+INF treated, AC+INF treated, and PEG+INF treated. All materials were aspirated into the lungs at a volume of 1 mL/kg. Before aspiration, the rats were injected subcutaneously with INF. Seven days later, both lungs and serum specimens in all groups were evaluated histopathologically, immunohistochemically, and biochemically. Following aspiration of AC and PEG, evident histopathological changes were assigned in the lung tissue that were associated with increased expression of inducible nitric oxide synthase (iNOS), increased serum levels of oxidative stress markers (malondialdehyde [MDA], surfactant protein-D [SP-D], TNF-α), and decreased antioxidant enzyme (glutathione peroxidase [GSH-Px]) activities. INF treatment significantly decreased the elevated serum MDA and TNF-α levels and increased serum GSH-Px levels. Furthermore, the current results show that there is a significant reduction in the activity of iNOS in lung tissue and increased serum SP-D levels of AC and PEG aspiration-induced lung injury with INF treatment. These findings suggest that INF attenuates lung inflammation and prevents GI decontamination agent-induced lung injury in rats.  相似文献   
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