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991.
Breast cancer is the second most frequent cancer in Sub-Saharan African women with an incidence of 15-53 per 100,000 women. Using PubMed, we reviewed all the articles published on this topic between 1989 and 2009. Breast cancer is usually diagnosed in women younger than in developed countries (mean age: 42-53 years), with later stages (III or IV, i.e. with axillary nodes and distant metastases). Reported tumors are mostly invasive ductal carcinomas with aggressive characteristics: grade III histoprognosis, absence of hormonal receptors or HER2 expression. According to the new breast cancer classification, nearly half of these tumors should be classified as triple negative. However, studies are rare and require confirmation. In conclusion, data on epidemiology and biology of breast cancer in Sub-Saharan African women are still scarce and need more extensive studies. In these countries, the pattern of breast cancer will likely change in the future, according to the evolution of lifestyle namely urbanisation. There is a great need for commitment of research and clinical resources in Sub-Saharan Africa in order to develop specific strategies.  相似文献   
992.
Immune escape in cancer poses a substantial obstacle to successful cancer immunotherapy. Multiple defects in HLA class I antigen presentation exist in cancer that may contribute to immune escape, but less is known about roles for HLA class II antigen presentation. On class II(+) leukemic blasts, the presence of class II-associated invariant chain peptide (CLIP) is known to be correlated with poor survival in acute myeloid leukemia (AML). In this study, we evaluated the functional significance of CLIP expression on leukemic blasts of AML patients. CD4(+) T cells from patients were cocultured with autologous CLIP(-) and CLIP(+) primary leukemic blasts and analyzed for several functional parameters by flow cytometry. Increased HLA-DR and IFN-γ expression was observed for CD4(+) T cells stimulated with CLIP(-) leukemic blasts, in contrast to CLIP(+) leukemic blasts, which indicated an activation and polarization of the CD4(+) T cells toward T-helper 1 cells. In addition, CLIP(-) leukemic blasts induced greater outgrowth of effector memory CD4(+) T cells (with HLA-DR-restricted T-cell receptor Vβ repertoires) that were associated with better leukemia-specific reactivity than with CLIP(+) leukemic blasts. Our findings offer a clinical rationale to downmodulate CLIP on leukemic blasts as a strategy to degrade immune escape and improve leukemia-specific T-cell immunity in AML patients.  相似文献   
993.
Cervical cancer is a public health concern as it represents the second cause of cancer death in women worldwide. High-risk human papillomaviruses (HPV) are the etiologic agents, and HPV E6 and/or E7 oncogene-specific therapeutic vaccines are under development to treat HPV-related lesions in women. Whether the use of mucosal routes of immunization may be preferable for inducing cell-mediated immune responses able to eradicate genital tumors is still debated because of the uniqueness of the female genital mucosa (GM) and the limited experimentation. Here, we compared the protective activity resulting from immunization of mice via intranasal (i.n.), intravaginal (IVAG) or subcutaneous (s.c.) routes with an adjuvanted HPV type 16 E7 polypeptide vaccine. Our data show that s.c. and i.n. immunizations elicited similar frequencies and avidity of TetE71CD81 and E7-specific Interferon-gamma-secreting cells in the GM, whereas slightly lower immune responses were induced by IVAG immunization. In a novel orthotopic murine model, both s.c. and i.n. immunizations allowed for complete long-term protection against genital E7-expressing tumor challenge. However, only s.c. immunization induced complete regression of already established genital tumors. This suggests that the higher E7-specific systemic response observed after s.c. immunization may contribute to the regression of growing genital tumors, whereas local immune responses may be sufficient to impede genital challenges. Thus, our data show that for an efficiently adjuvanted protein-based vaccine, parenteral vaccination route is superior to mucosal vaccination route for inducing regression of established genital tumors in a murine model of HPV-associated genital cancer.  相似文献   
994.
995.
Chromosome 17q21.31 microdeletion was one of the first genomic disorders identified by chromosome microarrays. We report here the clinical and molecular characterization of a new series of 14 French patients with this microdeletion syndrome. The most frequent clinical features were hypotonia, developmental delay and facial dysmorphism, but scaphocephaly, prenatal ischemic infarction and perception deafness were also described. Genotyping of the parents showed that the parent from which the abnormality was inherited carried the H2 inversion polymorphism, confirming that the H2 allele is necessary, but not sufficient to generate the 17q21.31 microdeletion. Previously reported molecular analyses of patients with 17q21.31 microdeletion syndrome defined a 493 kb genomic fragment that was deleted in most patients after taking into account frequent copy number variations in normal controls, but the deleted interval was significantly smaller (205 kb) in one of our patients, encompassing only the MAPT, STH and KIAA1267 genes. As this patient presents the classical phenotype of 17q21.31 syndrome, these data make it possible to define a new minimal critical region of 160.8 kb, strengthening the evidence for involvement of the MAPT gene in this syndrome.  相似文献   
996.
To continue to improve life expectancy and quality of life, the discovery of innovative therapies should be among the prime goals of the life sciences. The large majority of the drugs that are discovered and successfully developed to the point of being used by patients come from the drug industry, but publications from this sector are rare among life sciences research publications. Publications in the field of pharmaceutical drug discovery should take into account the confidentiality inherent to the protection of the intellectual property rights of a discovery, but they are fundamentally important because they can enhance scientific knowledge, improve the care and safety of patients, provide information for prescribers, and educate the public about the pharmaceutical industry.  相似文献   
997.
The bradykinin (BK) B1 receptor is an attractive target for the treatment of chronic pain and inflammation. Starting from a dual B1 and B2 antagonist, novel antagonists were designed that display low-nanomolar affinity for human B1 receptor and selectivity over B2. Initially, potent imidazoline derivatives were studied, but these compounds suffered from low bioavailability. This issue could be overcome by the use of less basic amino derivatives leading to orally active compounds.  相似文献   
998.

Rationale

JNJ-37822681 is a highly selective, fast dissociating dopamine D2-receptor antagonist being developed for the treatment of schizophrenia. A single dose [11C]raclopride positron emission tomography (PET) imaging study had yielded an estimated clinical dose range. Receptor occupancy at steady state was explored to test the validity of the single-dose estimates during chronic treatment.

Objectives

The aims of this study are to characterize single and multiple dose pharmacokinetics and obtain striatal D2-receptor occupancies to predict doses for efficacy studies and assess the safety and tolerability of JNJ-37822681.

Methods

An open-label single- and multiple-dose study with 10?mg JNJ-37822681 (twice daily for 13 doses) was performed in 12 healthy men. Twenty [11C]raclopride PET scans (up to 60?h after the last dose) from 11 subjects were used to estimate D2-receptor occupancy. A direct effect O max model was applied to explore the relationship between JNJ-37822681 plasma concentration and striatal D2-receptor occupancy.

Results

Steady state was reached after 4?C5?days of twice daily dosing. JNJ-37822681 plasma concentrations of 3.17 to 63.0?ng/mL resulted in D2 occupancies of 0?% to 62?%. The concentration leading to 50?% occupancy was 18.5?ng/mL (coefficient of variation 3.9?%) after single dose and 26.0?ng/mL (8.2?%) at steady state. JNJ-37822681 was well tolerated.

Conclusions

Receptor occupancy after single dose and at steady state differed for JNJ-37822681 and the robustness of the estimates at steady state will be tested in phase 2 studies. Dose predictions indicated that 10, 20, and 30?mg JNJ-37822681 twice daily could be suitable for these studies.  相似文献   
999.
1000.
Among the 1700 mutations reported in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, a missense mutation, p.Ser1235Arg, is a relatively frequent finding. To clarify its clinical significance, we collected data from 104 subjects heterozygous for the mutation p.Ser1235Arg from the French CF network, addressed for various indications including classical CF, atypical phenotypes or carrier screening in subjects with or without a family history. Among them, 26 patients (5 having CF, 10 CBAVD (congenital bilateral absence of the vas deferens) and 11 with CF-like symptoms) and 14 healthy subjects were compound heterozygous for a second CFTR mutation. An exhaustive CFTR gene analysis identified a second mutation in cis of p.Ser1235Arg in all CF patients and in 81.8% CBAVD patients. Moreover, epidemiological data from >2100 individuals found a higher frequency of p.Ser1235Arg in the general population than in CF or CBAVD patients. These data, added to the fact that in silico analysis and functional assays suggest a benign nature of this substitution, give several lines of evidence against an association of p.Ser1235Arg with CF or CBAVD.  相似文献   
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