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Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g., nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an alternative for treatment of symptomatic biliary leakage instead of immediate reoperation. Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation).  相似文献   
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The host immune response to intracellular transgenes delivered by helper-dependent (HDV) vs. first generation (FGV) adenoviral vectors has been relatively unstudied. Previous studies showed short-term correction of bovine and murine argininosuccinate synthetase (ASS) deficiency after first generation adenoviral-mediated liver gene therapy. To determine whether the host adaptive immune response against the intracellular transgene human ASS (hASS) contributed to loss of gene expression in this setting, the same vector (FGV-CAG-hASS) was injected into Rag-/- (immunodeficient) mice. As in wild-type C57BL/6 (B6) mice, Rag-/- mice also showed significant loss of hASS expression and vector by week 4 post-injection, with concomitant elevation of liver enzymes and disruption of liver architecture. Therefore, direct toxicity due to vector rather than adaptive immune response against hASS primarily accounted for loss of expression with FGVs. In contrast to hASS, beta-galactosidase is strongly immunogenic and activates the host adaptive immune response. Loss of transgene expression was observed in B6 mice with either a FGV or a HDV expressing beta-galactosidase. However, the drop in gene expression observed with the HDV was primarily due to the adaptive immune response, since both beta-galactosidase expression and vector genome were sustained in immunodeficient mice treated with HDV. As expected, with weakly immunogenic hASS, vector genome and hASS expression were sustained with a HDV in spite of ubiquitous expression of the transgene. Therefore, viral gene expression is a primary determinant of intermediate and chronic toxicities at day 3 and week 4 post-injection. However, even in the absence of viral gene expression, strongly immunogenic intracellular transgenes can stimulate clearance of transduced hepatocytes.  相似文献   
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The health care delivery system in Pakistan is in a process of rapid growth, and it consists of public and private sectors. The provincial government is preliminarily responsible for providing health care facilities within its province except in federally administered areas. In Pakistan, there are three tiers of governmental healthcare delivery systems, which comprise government, semi-government, and parastatal organizations. The purpose of this study is to understand the rapid increase in influx of patients in major city hospitals of the Punjab province. The reasons for patient flow towards the major city areas can vary, but our point of focus is mainly on those patients who are prescribed to get a computed tomography (CT) scan done for better diagnosis and early treatment, including but not limited to roadside accident cases. The study targets the define, measure, analyze, improve and control (DMAIC) problem solving approach to assess the potential cause of CT patient flow and the challenges that the health department is facing to cater to such a patient niche and process while minimizing the congestion in city government hospitals. The approach in this study summarizes with numerous quality tools like Voice of Customer (VOC) which is customer feedback, Customer Output Process Input and Supplier (COPIS) processes use for high-level process map to know what your customer value, Approver Resource Member Interested (ARMI) chart which is use to analyze the stakeholders on management of the project, evaluation with the help of fishbone diagram and house of quality, and for process improvement methodology we use the team brainstorming technique and the kaizen 5-why technique. The technique came up with an idea of a public-private partnership (PPP) project—partnership between public agency and private firm, as the health care industry in Punjab province is going through budgetary issues. In a PPP project, the Government will allocate the space to a private firm to build the facility on their own and provide quality service for CT scan diagnosis to the public of Punjab. The study identified the top 10 critical factors that the patients have expected from the government to be provided on priority. The Kaizen process improvement methodology has been adopted to provide the possible solution of government budgetary issues. The set of tools in this study can be adopted by other PPP projects to enhance the project performance.  相似文献   
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The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.

The enlarged central part MH loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe.  相似文献   
7.
In this study, an artificial intelligence tool called gene expression programming (GEP) has been successfully applied to develop an empirical model that can predict the shear strength of steel fiber reinforced concrete beams. The proposed genetic model incorporates all the influencing parameters such as the geometric properties of the beam, the concrete compressive strength, the shear span-to-depth ratio, and the mechanical and material properties of steel fiber. Existing empirical models ignore the tensile strength of steel fibers, which exercise a strong influence on the crack propagation of concrete matrix, thereby affecting the beam shear strength. To overcome this limitation, an improved and robust empirical model is proposed herein that incorporates the fiber tensile strength along with the other influencing factors. For this purpose, an extensive experimental database subjected to four-point loading is constructed comprising results of 488 tests drawn from the literature. The data are divided based on different shapes (hooked or straight fiber) and the tensile strength of steel fiber. The empirical model is developed using this experimental database and statistically compared with previously established empirical equations. This comparison indicates that the proposed model shows significant improvement in predicting the shear strength of steel fiber reinforced concrete beams, thus substantiating the important role of fiber tensile strength.  相似文献   
8.
Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes. Based on this principle, fluorescent probes (1a–c) were synthesized, and they displayed excellent aggregation induced emission (AIE) behavior in a H2O/DMF (4 : 1, v/v) mixture due to restrictions in intramolecular charge transfer (ICT). As a comparison, probe 1d was synthesized by installing an electron withdrawing (–NO2) group that surprisingly quenched the aggregation behaviour. Additionally, AIE active probes 1a–c displayed a highly sensitive dual channel (fluorometric and colorimetric) response towards rapid detection of CN, which is an active toxic material. Probes 1a–c showed selectively enhanced fluorescence emission behavior towards CN with detection limits of 1.34 ppb, 1.38 ppb, and 1.54 ppb, respectively. The sensing mechanism involves Michael type adduct formation due to the nucleophilic addition reaction of cyanide with probes and was confirmed through 1H NMR titration experiments. In contrast, probe 1d containing an electron withdrawing moiety showed insensitivity towards CN. Therefore, this study provides the efficient strategy to induce AIE character in fluorescent probes and expands the mechanistic approach toward the sensing of toxic CN.

Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes.  相似文献   
9.
Chordoma is a rare malignant neoplasm derived from notochordal tissue that primarily affects the axial skeleton. Almost 40% of patients have non-cranial chordoma metastases. The most common metastatic sites are the lungs, bones, lymph nodes, and subcutaneous tissue. We present a 52-year female with a history of sacral chordoma presenting with abdominal fullness, early satiety, and a palpable abdominal mass. Abdominal magnetic resonance imaging (MRI) revealed an isolated, highly vascularized, and multilobed liver mass in the left lateral segment. The mass was surgically removed using a clean surgical margin. A histological examination and immunohistochemical staining were consistent with a metastatic chordoma. Two years later, follow-up imaging studies showed a 6.5 × 4.0 × 2.0 cm right liver lesion with multiple lungs, chest wall, pleural, and diaphragmatic lesions. Microscopic- and immunohistochemical staining revealed a recurrent metastatic chordoma. Herein, we present a unique case of metastatic recurrent chordoma in the liver with the involvement of other sites. To the best of our knowledge, no other case of recurrent liver metastasis has been reported.  相似文献   
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