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81.
82.
Many orthopedic articles describe advances in surgical techniques and implants used in pediatric scoliosis surgery. However, even though postoperative spine imaging constitutes a large portion of outpatient musculoskeletal pediatric radiology, few, if any, radiology articles discuss this topic. There has been interval advancement over the last decades of the orthopedic procedures used in the treatment of spinal scoliosis in adolescents with idiopathic scoliosis. The goal of treatment in these patients is to stop the progression of the curve by blocking the spinal growth and correcting the deformity as much as possible. To that end, the authors in this paper discuss postoperative imaging findings of Harrington rods, Luque rods, Luque–Galveston implants and segmental spinal fusion systems. Regarding early onset scoliosis, the guiding principles used for adolescent idiopathic scoliosis do not apply to a growing spine because they would impede lung development. As a result, other devices have been developed to correct the curve and to allow spinal growth. These include spine-based growing rods, vertically expandable prosthetic titanium rods (requiring repetitive surgeries) and magnetically controlled growing rods (with a magnetic locking/unlocking system). Other more recent systems are Shilla and thoracoscopic anterior vertebral body tethering, which allow guided growth of the spine without repetitive interventions. In this paper, we review the radiologic appearances of different orthopedic implants and techniques used to treat adolescent idiopathic scoliosis and early onset scoliosis. Moreover, we present the imaging findings of the most frequent postoperative complications.  相似文献   
83.
A new triterpenoidal saponin identified as 3-O-[β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-xylopyranosyl]-2β,3β,16α-trihydroxyolean-12-en-23,28-dioic acid-28-O-α-l-rhamnopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranoside 1 together with a new oleanane triterpene identified as 2β,3β,13α,22α-tetrahydroxy olean-23,28-dioic acid 2 and 6 known compounds (3–8) have been isolated from Gladiolus segetum Ker-Gawl corms. The structural elucidation of the isolated compounds was confirmed using different chemical and spectroscopic methods, including 1D and 2D NMR experiments as well as HR-ESI-MS. Moreover, the in vitro cytotoxic activity of the fractions and that of the isolated compounds 1–8 were investigated against five human cancer cell lines (PC-3, A-549, HePG-2, MCF-7 and HCT-116) using doxorubicin as a reference drug. The results showed that the saponin fraction exhibited potent in vitro cytotoxic activity against the five human cancer cell lines, whereas the maximum activity was exhibited against the PC-3 and A-549 cell lines with the IC50 values of 1.13 and 1.98 μg mL−1, respectively. In addition, compound 1 exhibited potent activity against A-549 and PC-3 with the IC50 values of 2.41 μg mL−1 and 3.45 μg mL−1, respectively. Interestingly, compound 2 showed the maximum activity against PC-3 with an IC50 of 2.01 μg mL−1. These biological results were in harmony with that of the molecular modeling study, which showed that the cytotoxic activity of compound 2 might occur through the inhibition of the HER-2 enzyme.

A new triterpenoidal saponin 1, a new oleanane triterpene 2, and 6 known compounds (3–8) have been isolated from Gladiolus segetum Ker-Gawl corms.  相似文献   
84.
A major part of the science of pharmacokinetics is the modeling of the underlying processes that contribute to drug disposition. The purpose of pharmacokinetic models is to summarize the knowledge gained in preclinical and clinical studies at various stages in drug development and to rationally guide future studies with the use of adequately predictive models. This review highlights a variety of recent advances in mechanistic pharmacokinetic modeling. It is aimed at a broad audience, and hence, an attempt was made to maintain a balance between technical information and practical applications of pharmacokinetic modeling. It is hoped that drug researchers from all disciplines would be able to get a flavor of the function and capacity of pharmacokinetic modelers and their contribution to drug development. While this review is not intended to be a technical reference on modeling approaches, the roles of statistical applications and population methodologies are discussed where appropriate.  相似文献   
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The potential anti-tumour activity of non-steroidal anti-inflammatory drugs (NSAIDS) has been previously discussed. This study was undertaken to assess the possible anti-tumour activity of the cyclooxygenase-2 (COX-2) inhibitor; celecoxib in an animal model of mammary carcinoma; the solid Ehrlich carcinoma (SEC). The possibility that celecoxib may modulate the anti-tumour activity of doxorubicin on the SEC was also studied. Some of the possible mechanisms underlying such modulation were investigated. The anti-tumour activity of celecoxib (25 mg kg(-1)), diclofenac (12.5 mg kg(-1)) and doxorubicin (2 mg kg(-1)) either alone or in combination were investigated on SEC in vivo through the assessment of tumour growth delay (TGD) and tumour volume (TV), changes in tumour DNA content and nitric oxide (NO) levels, immunohistochemical staining of the tumour suppressor gene product; p53 histopathological examination and determination of apoptotic index of SEC. In addition, the influence of these drugs on the DNA fragmentation pattern of Ehrlich carcinoma cells (ECC) was studied. It was found that both celecoxib and diclofenac lack the anti-tumour activity on SEC. In addition there was a significant increase in doxorubicin anti-tumour activity when administered in combination with celecoxib. Moreover, it was found that both celecoxib and diclofenac have the potential to inhibit the function of P-glycoprotein (P-gp) in ECC using rhodamine uptake and efflux assays. Therefore, the current study suggested the chemosensitizing potential of celecoxib in the SEC animal model of mammary tumour, which could be explained in part on the basis of inhibition of P-gp function, with possible enhancement of doxorubicin anti-tumour activity.  相似文献   
87.
Intralesional (IL) vitamin D3 is an emerging treatment for cutaneous warts. However, its effectiveness and exact mechanism is not fully evaluated. We aimed to compare the efficacy and safety of IL purified protein derivative (PPD) and IL vitamin D3 in multiple warts and to investigate their systemic effect clinically and immunologically. Forty‐five patients with multiple extragenital warts were treated with IL‐PPD (22 patients) or IL vitamin D3 injection (23 patients) for a maximum of three sessions at 3 week intervals. Decrease in size and number of warts and adverse effects were evaluated. Serum interleukin‐12 (IL‐12) and interferon‐gamma (IFN‐γ) levels were measured before and 3 weeks after the last session. Higher clearance rates for all warts were observed with IL‐PPD compared to IL vitamin D (59.1% vs. 21.7% complete clearance, p < .001). Significant increase was found in both serum IL‐12 and IFN‐γ after PPD treatment (p = .034 and p = .04, respectively), but only IFN‐γ after vitamin D3 treatment (p = 0.02). Both IL vitamin D3 and PPD showed positive results in treatment of multiple warts. However, PPD showed higher clinical efficacy and more increase in both IL‐12 and IFN‐γ levels.  相似文献   
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This study was planned to evaluate prospectively the results of 150 patients with pilonidal sinus treated surgically after planning a score system. The aim was to choose the proper technique for the proper pilonidal sinus disease. From November 2002 to December 2006, 150 patients [130 male, 20 female; average age = 22.65 ± 4.2 (range, 15-46) years] with primary or recurrent pilonidal sinus diseases, operated under spinal anaesthesia or general anaesthesia. All patients were classified into three groups A, B and C. According to the clinical presentations we had three groups of patients: Group A with a score number n = 8 to 10, Group B with a score number n = 11 to 13, and Group C had the number n = 14 to 16. The study helped us in our surgical decision making, particularly in choosing the type of surgery for a given patient by our new scoring system, with promising results and low failure rate.  相似文献   
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