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131.
Recent studies have speculated on the possible role of the mother in transmitting Helicobacter pylori infection to their children. In an attempt to either prove or disprove this supposition, we investigated the rates of infection of children born to H. pylori-positive mothers from birth to 5 years of age using serology and the stool antigen test. When infection of the children did occur, the strains from the children were compared to those of their mothers using DNA analysis. Sixty-nine of the 350 pregnant mothers (19.7%) had a positive serology for H. pylori. Fifty-one children underwent serological examinations and stool antigen tests at 4 to 6 days after birth, followed by 1, 3, and 6 months. They were continuously given the stool antigen test at 4- to 6-month intervals until the age of 5 years. Gastric juice samples were collected from the infected children and their mothers for culture and DNA analyses using a random amplified polymorphic DNA fingerprinting method. None of the 51 children acquired H. pylori infection during the first year of life. Of the 44 children enrolled in a 5-year follow-up study, five (11%) acquired H. pylori infection. They acquired the infection at the age of 1 year 2 months, 1 year 3 months, 1 year 6 months, 1 year 8 months, and 4 years 4 months. Random amplified polymorphic DNA fingerprinting confirmed that the strains of the five children exhibited DNA fingerprinting patterns identical to those of their mothers. These findings suggest that mother-to-child transmission is the most probable cause of intrafamilial spread of H. pylori.  相似文献   
132.
The interest in small animal models of human diseases has generated a need to design a computed tomography (CT) system that operates at a microscopic level. It is particularly important to be able to visualize the dramatic rhythmical motion of organs such as the heart and lungs. In order to evaluate the motion of the heart and lungs of small animals (rats and mice), we developed in the present study a high-resolution 4D in vivo-CT system for small animals that uses synchrotron radiation. To reduce motion artifacts and the radiation dose, the projections were synchronized with airway pressure, the ECG, the x-ray shutter and the CCD shutter. For cardiovascular imaging, a blood pool contrast agent was injected and the data sets were acquired at several ECG points during the end-expiratory phase. For imaging of the lungs, the data sets were acquired at several airway pressures during diastole. The dynamic motion of the cardiovascular system (the ventricles and coronary arteries) and small airways (diameter > 250 microm of rats and 125 microm of mice) was visualized. This high-resolution imaging tool may be very useful for the development of novel drugs in murine models, in addition to its use in the study of cardiovascular and respiratory physiology.  相似文献   
133.
Helicobacter pylori infection causes atrophic gastritis, peptic ulcer, and gastric cancer. The host immune response plays an important role in the pathogenesis of H. pylori-related diseases. Heat shock proteins are antigens involved in various diseases. This study evaluated seropositivity for antibodies to H. pylori heat shock protein 60 in patients with gastric cancer.  相似文献   
134.
135.
We report that clearance of Pseudomonas aeruginosa, accumulation of neutrophils, and synthesis of tumor necrosis factor alpha and macrophage inflammatory protein 2 in the infected lung were not largely different in interleukin-18 (IL-18) knockout or transgenic mice compared with control mice. Our results suggest a limited role for IL-18 in the host defense against P. aeruginosa.  相似文献   
136.
137.
The performance of a chemical luminescence test reagent "Immulyze IL-2R II" with an automated immune chemiluminescent system "IMMULITE 2000XPi" for the measurement of serum soluble IL-2 receptor in clinical samples was investigated. The satisfactory results were obtained for the reproducibility, precision, linearity, and sensitivity, and no interference with hemolysis, bilirubin, chyle or intrafat was observed. A significant correlation was found between the values of sIL-2R measured by the Cell-free N IL-2R and those obtained by the IMMULYZE IL-2R II. The measurements were stable regardless of the methods of sample preservation, or repeated freeze-thawing procedures. Elevated concentrations of sIL-2R over 1,000 U/mL were found in multiple types of collagen diseases or severe cases of allergic diseases, indicative that sIL-2R levels might correlate with the severity of autoimmune diseases. In patients with lymphoma, sIL-2R levels correlated with the lactate dehydrogenase (LD) activity. Among the lymphoma cases with sIL-2R levels over 1,000 U/mL, the majority (84%) had significantly higher levels of LD, and among them, 81% were at the clinical stage IV. We observed that sIL-2R levels increased from the early stages of lymphoma, while LD activities increased at the advanced stages. Our present findings suggest that sIL-2R is a promising marker for the diagnosis of autoimmune and allergic diseases, and also for the diagnosis and staging of lymphomas.  相似文献   
138.
Joint loading is a recently developed loading modality, which can enhance bone formation and accelerate healing of bone fracture. Since mechanical stimulation alters expression of matrix metalloproteinases (MMPs) in chondrocytes, a question addressed herein was, does joint loading alter actions of MMPs in the articular cartilage? We hypothesized that expression and activity of MMPs are regulated in a load-intensity-dependent manner and that moderate load scan downregulates MMPs. To test this hypothesis, a mouse elbow-loading model was employed. In the articular cartilage of an ulna, the mRNA levels of a group of MMPs as well as their degenerative activities were determined. The result revealed that elbow loading altered the expression and activities of MMPs depending on its loading intensity. Collectively, the data in this study indicate that 0.2 and 0.5?N joint loading significantly reduced the expression of multiple MMPs, that is, MMP-1, MMP-3, MMP-8, and MMP-13, and overall activities of collagenases or gelatinases in articular cartilage, while higher loads increased the expression and activity of MMP-1 and MMP-13. Furthermore, moderate loads at 1 N elevated the mRNA level of CBP/p300-interacting transactivator with ED-rich tail 2 (CITED2), but higher loads at 4 N did not induce a detectable amount of CITED2 mRNA. Since CITED2 is known to mediate the downregulation of MMP-1 and MMP-13, the result indicates that joint loading at moderate intensity reduces MMP activities through potential induction of CITED2. MMPs such as MMP-1 and MMP-13 are predominant collagenases in the pathology of osteoarthritis. Therefore, joint loading could offer an interventional regimen for maintenance of joint tissues.  相似文献   
139.
Measurements of autoantibodies are served for diagnosis of autoimmune diseases in routine. Results of UniCAP EliA (Phadia), based on fluorescence-enzyme immunoassay, were compared to those of the current ELISA method, MESACUP DNA-II test [ds] and MESACUP-2 test (MBL) with total of 404 sera. The full automated instrument of UniCAP 250 was used for measurement of UniCAP EliA. The CVs of within day reproducibility (n=10) were 3.0-9.6% by UniCAP EliA, meanwhile 1.7-11.7% by MESACUP. The CVs of between day reproducibility(5 days) were 1.0-11.8% by UniCAP EliA, meanwhile 1.0-19.9% by MESACUP. The concordance of U1RNP, SS-A/Ro, SS-B/La, Scl-70 and Jo-1 between UniCAP EliA and MESACUP were 89.5-100%, but the positive concordance in dsDNA, Sm andJo-1 showed lower concordance percentage (40.0-62.9%). UniCAP EliA had better reproducibility than MESACUP. Some sera showed discrepant results between UniCAP EliA and MESACUP. These discrepancies might be occurred by the purification of antigens or different measurement principle of kits. The antigens' purification of UniCAP EliA seemed enough for the routine tests, and the results from UniCAP EliA would give high clinical importance.  相似文献   
140.
Familial gastric cancer: overview and guidelines for management   总被引:22,自引:1,他引:22       下载免费PDF全文
Families with autosomal dominant inherited predisposition to gastric cancer have been described. More recently, germline E-cadherin/CDH1 mutations have been identified in hereditary diffuse gastric cancer kindred. The need to have protocols to manage and counsel these families in the clinic led a group of geneticists, gastroenterologists, surgeons, oncologists, pathologists, and molecular biologists to convene a workshop to produce consensus statements and guidelines for familial gastric cancer. Review of the available cancer pathology from people belonging to families with documented germline E-cadherin/CDH1 mutations confirmed that the gastric cancers were all of the diffuse type. Criteria to define the different types of familial gastric cancer syndromes were agreed. Foremost among these criteria was that review of histopathology should be part of the evaluation of any family with aggregation of gastric cancer cases. Guidelines for genetic testing and counselling in hereditary diffuse gastric cancer were produced. Finally, a proposed strategy for clinical management in families with high penetrance autosomal dominant predisposition to gastric cancer was defined.  相似文献   
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