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71.
Som  PM; Krespi  YP 《Radiology》1979,133(2):341
  相似文献   
72.
Relapsing polychondritis studied by computed tomography   总被引:1,自引:0,他引:1  
Mendelson  DS; Som  PM; Crane  R; Cohen  BA; Spiera  H 《Radiology》1985,157(2):489-490
Computed tomographic findings in a patient with relapsing polychondritis are described. Collapse of the cartilage of the nose and calcification in cartilages of the ears were clearly demonstrated. CT scanning was also helpful in evaluating the tracheobronchial tree for airway compromise, which could prove fatal in this condition.  相似文献   
73.
74.
BACKGROUND: Food allergy can lead to severe, potentially life-threatening anaphylactic reactions. To generate efficient strategies aimed at an active cure, a better understanding of the pathogenic mechanisms is strongly needed. OBJECTIVE: To investigate T-cell-related mechanisms of food allergy and tolerance to beta-lactoglobulin (BLG) in gut-associated lymphoid structures. METHODS: Beta-lactoglobulin-specific IgG1, IgG2a, and IgE in serum from mice anaphylactic to BLG were analyzed by ELISA and compared with those obtained in mice actively tolerized to BLG. The number of Ab-secreting cells in the spleen and in Peyer patches was determined by ELISPOT. The numbers of cytokine-producing cells after antigen-specific activation were measured by the same method. Furthermore, mesenteric lymph node cells and Peyer patches cells were transferred to naive mice, and Ab production as well as Ab-secreting cells were measured. RESULTS: Serum IgG1 and IgE Ab titers as well as IL-4-producing cell numbers were strongly increased in anaphylactic mice. IL-10 was found in Peyer patch cells from tolerant mice after BLG activation but not in anaphylactic mice. Peyer patch cells, in contrast to mesenteric lymph node cells, proliferated weakly in anaphylactic mice after antigen activation, and activation of Peyer patches was partially inhibited by tolerization. CONCLUSIONS: Our data suggest a specific role for lymphocytes in Peyer patches in tolerance to BLG. Low IL-10 production in Peyer patches may favor symptoms of food allergy.  相似文献   
75.
Background Lung cancer is the most common cause of cancer-related death in Ireland. There are few complete data sets available as to the stage and cell type of lung cancers at time of presentation in Ireland. Aim To audit the lung cancers presenting to a large Dublin teaching hospital over a 12-month period. Method Prospective evaluation of all lung tumours presenting to our institution over a consecutive 12-month period. Results One hundred and ninety-eight lung cancers presented over the study period. There were 34 cases of small cell carcinoma and 150 cases of non-small cell carcinoma (NSCC). Fourteen patients were too ill or compromised at time of presentation for tissue confirmation. The most common cell type was squamous carcinoma. Eighty-four per cent of the NSCCs were either stage 3 or 4 at presentation. Conclusion Most lung cancers present late in the time course of the disease. Distribution of cell type and location are similar in Ireland and other developed countries.  相似文献   
76.
Nerve growth factor and its receptors in asthma and inflammation   总被引:7,自引:0,他引:7  
Nerve growth factor (NGF) is a high molecular weight peptide that belongs to the neurotrophin family. It is synthesized by various structural and inflammatory cells and activates two types of receptors, the TrkA (tropomyosin-receptor kinase A) receptor and the p75NTR receptor, in the death receptor family. NGF was first studied for its essential role in neuronal growth and survival. Recent reports indicate that it may also help mediate inflammation, especially in the airways. Several studies in animals have reported that NGF may induce bronchial hyperresponsiveness, an important feature of asthma, by increasing sensory innervation. It may also induce migration and activation of inflammatory cells, which infiltrate the bronchial mucosa, and of structural cells, including epithelial, smooth muscle cells and pulmonary fibroblasts. Increased NGF expression and release is observed in asthma patients after bronchial provocation with allergen. Taken together, the data from the literature suggest that NGF may play a role in inflammation, bronchial hyperresponsiveness and airway remodelling in asthma and may help us to understand the neuro-immune cross-talk involved in chronic inflammatory airway diseases.  相似文献   
77.
We investigated the distribution of the broad-spectrum antibiotic fosfomycin in infected soft tissue of patients with uncomplicated cellulitis of the lower extremities or diabetic foot infection using in vivo microdialysis. Our findings suggest that fosfomycin exhibits good and similar penetration into the fluid in the interstitial space in inflamed and noninflamed soft tissue in patients.  相似文献   
78.
Expression of cytochromes P450 (CYP) and glutathione S-transferases in the lung may be affected by inhaled pollutants. We have investigated the effect of sulfur mustard on the expression of CYP 1A1, 2B1, 2E1 and 3A1, as well as of alpha-, micro- and pi-glutathione S-transferases in rat lung. Sulfur mustard (0.025, 0.05 or 0.1 mg/kg) or its vehicle was administered to anaesthetized animals by intratracheal injection. Expression of CYP and glutathione S-transferases was analysed 24 hr after administration of the vesicant warfare using western blotting. Preservation of airway epithelium integrity after animal exposure to sulfur mustard was confirmed by histological examination of tracheal and lung tissues from control and treated animals. Constitutive levels of CYP 2B1 and 3A1 proteins were found in lung tissue from control rats, whereas CYP 1A1 and 2E1 proteins were not detected. Animal exposure to sulfur mustard enhanced CYP 3A1 protein levels by 80 to 103%. In contrast, exposure to sulfur mustard neither modified CYP 2B1 expression, nor led to detectable expression of CYP 1A1 or 2E1. Constitutive levels of alpha-, micro- and pi-glutathione S-transferase proteins were found in lung tissue from control rats. Exposure to sulfur mustard had no effect on expression of either of the glutathione S-transferases. Our results show that intratracheal exposure to sulfur mustard selectively increases CYP 3A1 expression in rat lung. Taking into account the major role of CYP of the 3A family in the metabolism of drugs, up-regulation of CYP 3A1 by sulfur mustard might have important therapeutic consequences.  相似文献   
79.
Ren  S; Wong  BY; Li  J; Luo  XN; Wong  PM; Atweh  GF 《Blood》1996,87(6):2518-2524
The ability to generate stable high-titer vectors that give rise to high levels of expression of transduced globin genes in erythroid cells is a prerequisite for effective retroviral-mediated globin gene therapy. The human beta-globin gene with its immediate flanking sequences does not contain all the regulatory elements necessary for regulated high-level and position-independent expression in erythroid cells. The regulatory element known as the beta-globin locus control region (BetaLCR) can provide a linked Beta-globin gene with these properties. However, addition of BetaLCR sequences to a retrovirus carrying a beta-globin gene increases its genetic instability. We have developed a new generation of retroviral vectors in which a human gamma- globin gene is placed under the control of the alphaLCR, the major regulatory element of the alpha-globin gene cluster. We demonstrate that these retroviruses are genetically stable in producer cell lines and can be produced at high titers that exceed 5 x 10(6) colony-forming units (CFU)/mL. In addition, we show that the transduced gamma-globin gene can be expressed in the adult erythroid environment of mouse erythroleukemia (MEL) cells at a level comparable to that of a single endogenous Betamaj-globin gene. These retroviruses can also transduce primary murine bone marrow progenitor cells as efficiently as retroviruses that carry the neomycin resistance (neor) gene. This new generation of globin retroviral vectors may prove useful for gene therapy of human beta-globin gene disorders such as sickle cell disease and beta-thalassemia.  相似文献   
80.
Autoimmune pancreatitis (AIP) is a type of immune-mediated pancreatitis subdivided into two subtypes, type 1 and type 2 AIP. Furthermore, type 1 AIP is considered to be the pancreatic manifestation of the immunoglobulin G4 (IgG4)-related disease. Nowadays, AIP is increasingly researched and recognized, although its diagnosis represents a challenge for several reasons: False positive ultrasound-guided cytological samples for a neoplastic process, difficult to interpret levels of IgG4, the absence of biological markers to diagnose type 2 AIP, and the challenging clinical identification of atypical forms. Furthermore, 60% and 78% of type 1 and type 2 AIP, respectively, are retrospectively diagnosed on surgical specimens of resected pancreas for suspected cancer. As distinguishing AIP from pancreatic ductal adenocarcinoma can be challenging, obtaining a definitive diagnosis can therefore prove difficult, since endoscopic ultrasound fine-needle aspiration or biopsy of the pancreas are suboptimal. This paper focuses on recent innovations in the management of AIP with regard to the use of artificial intelligence, new serum markers, and new therapeutic approaches, while it also outlines the current management recommendations. A better knowledge of AIP can reduce the recourse to surgery and avoid its overuse, although such an approach requires close collaboration between gastroenterologists, surgeons and radiologists. Better knowledge on AIP and IgG4-related disease remains necessary to diagnose and manage patients.  相似文献   
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