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961.
Vascular cell adhesion molecule-1 (VCAM-1, CD106) is important in leukocyte trafficking and its increased expression is associated with a number of chronic inflammatory diseases, including rheumatoid arthritis (RA). A soluble form of VCAM-1 (sVCAM-1) is generated by shedding of the membrane-bound molecule. The concentration of sVCAM-1 is increased in the sera of RA patients, but its pathological role has not been elucidated. The effect of sVCAM-1 relative to protection or aggravation of disease on the development of spontaneous arthritis was examined in an animal model of RA, namely MRL-Fas(lpr) mice (which display a disease resembling human RA), by generation of sVCAM-1 transgenic MRL-Fas(lpr) mice. Transgenic MRL-Fas(lpr) mice that expressed sVCAM-1 had higher incidence and increased severity of arthritis associated with higher levels of serum IgG rheumatoid factor compared with non-transgenic MRL-Fas(lpr) mice. These results suggest that sVCAM-1 plays an arthritogenic role in the development of inflammatory arthritis in MRL-Fas(lpr) mice and may present an important target for therapeutic strategy of RA.  相似文献   
962.
An 80-year-old woman with a pleomorphic carcinoma (PC) producing hCG was admitted to Nippon Steel Hirohata Hospital because of an abnormal shadow on CT seen during a follow-up examination after surgery for breast cancer. A right upper lobectomy was performed due to rapid growth of the shadow 3 months later. Macroscopically the tumor was a 4.8 x 4.0 cm well-circumscribed grayish-white mass. On histology the tumor consisted mostly of intermingled spindle and polygonal cells, while evidence of poorly differentiated adenocarcinoma was seen in a few areas. A diagnosis of PC was made due to hCG expression in approximately 20% of the spindle and polygonal cells on immunohistology. Six months after the operation metastasis to the liver and adrenal gland was seen on CT. The patient died due to metastases 1 year after the operation, even though the patient had been at stage 1B at the time of the operation and appropriate chemotherapy had been given. PC patients with immunohistochemical hCG expression have elevated risk of local recurrence and metastasis.  相似文献   
963.
Mutations in p53 gene exons 5-9 were studied in 44 non-Hodgkin's lymphomas (NHL) consisting of 35 B-NHL and 9 T-NHL. Missense mutations were found in two diffuse large B-cell lymphomas (DLBL) and one peripheral T-cell lymphoma (unspecified). Double transversion missense and nonsense mutations were detected in one DLBL and one adult T-cell leukemia/lymphoma. Silent mutations were found in two DLBL. Detailed histomorphological study showed that cases harboring p53 missense mutation with/without nonsense mutation tended to have larger nuclei with much more prominent nucleoli. Cytomorphometric analysis was therefore conducted by measuring the gross area of 100 lymphoma cell nuclei in 44 cases and the results were compared between lymphomas harboring p53 missense mutation with/without nonsense mutation and lymphomas harboring p53 silent mutation or lacking mutation. It was found that the lymphomas harboring p53 missense mutation with/without nonsense mutation had a highly significantly larger nuclear gross area than lymphomas with silent p53 mutation or lacking mutation (two-sample t-test, P < 0.00001; Exact Wilcoxon rank-sum test, P < 0.00001). This result suggests that p53 mutation might induce enlargement of neoplastic cell nuclei by some molecular mechanism.  相似文献   
964.
Current methods including the use of various biological and synthetic sealants are ineffective in the closure of intraoperative air leaks that often occur during cardiothoracic surgeries, resulting in a decreased quality of life for patients. We present the development of a novel lung air leak sealant using tissue engineered cell sheets. In contrast to previous materials such as fibrin glue, these bioengineered cell sheets immediately and permanently seal air leaks in a dynamic fashion that allows for the extensive tissue contraction and expansion involved in respiration, without any postoperative recurrences. Additionally, we demonstrate that mesothelial cells migrate to cover the transplanted cells sheets, thereby confirming excellent biocompatibility and integration with the host tissues. Finally, we present the use of skin fibroblasts as an effective and readily available autologous cell source that can be easily applied. This study shows for the first time, the development of an immediate and permanent lung air leak sealant, suitable for future clinical applications.  相似文献   
965.
Hepatitis B virus (HBV) subgenotypes Cs (C1) and Ce (C2) are common in East Asia. To investigate the genomic difference of HBV genotype C between two separated regions, 50 subgenotype Cs-infected Vietnamese and 70 subgenotype Ce-infected Japanese patients were enrolled for analysis. The patients were categorized to either a hepatocellular carcinoma group (HCC) or a non-HCC group including liver cirrhosis, chronic hepatitis, and asymptomatic carriers. HBV serology, HBV-DNA level, and variations in core promoter/pre-core region were examined. Phylogenetic analysis based on the full genome sequences and nucleotide sequences partly in the S gene and in the P gene revealed that all Japanese strains (70/70) were subgenotype Ce, and nearly all of the Vietnamese strains (50/51) were subgenotype Cs, excluding one subgenotype C5. C1858 and G1775 were common in the Vietnamese (64% and 40%) but not in the Japanese (0%). The prevalence of C/A1753 in Vietnamese was higher than that in the Japanese (32% vs. 17.1%), however the frequency of A1896 in the Japanese was significantly higher (32.9% vs. 12%, P < 0.05). Most of the Vietnamese patients with HCC had a high level of HBV-DNA, the Japanese HCC had a relatively low level. In the Vietnamese, C/A1753 and C1858 were associated closely with T1762A1764, higher HBV-DNA levels and higher HCC incidence. The multivariate analysis revealed that male, T1653 and C/A1753 were independent risk factors for HCC. The subgenotypes and unique mutations of HBV genotype C in the Vietnamese and Japanese differed, and C/A1753 and C1858 variants might play a role in the pathogenesis of liver disease in Vietnamese patients.  相似文献   
966.
Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) causes SARS. The pathogenic mechanisms of SARS-CoV remain poorly understood. Six cynomolgus monkeys were inoculated with the HKU39849 isolate of SARS-CoV via four routes. After intranasal inoculation, the virus was isolated from respiratory swabs on days 2-7 postinoculation (p.i.) and virus genome was detected in intestinal tissues on day 7 p.i. Virus was not detected after intragastric inoculation. After intravenous inoculation, infectious virus was isolated from rectal swabs, and virus antigen was detected in intestinal cells on day 14 p.i. After intratracheal (i.t.) inoculation, virus antigen-positive alveolar cells and macrophages were found in lung and infectious virus was detected in lymphoid and intestinal tissues. The peribronchial lymph nodes showed evidence of an immune response. Lung tissue and/or fluid and/or the peribronchial lymph node of the intratracheally inoculated animals had high TNF-alpha, IL-8 and IL-12 levels. SARS lung lesions are only generated in monkeys by i.t. inoculation. The virus appears to spread into and perhaps via the intestinal and lymphatic systems. It has been suggested previously that viraemia may cause intestinal infections in SARS patients.  相似文献   
967.
Breast Cancer Research and Treatment - To investigate clinical usefulness of eribulin-based neoadjuvant chemotherapy in triple-negative breast cancer (TNBC) patients. Patients in group A...  相似文献   
968.
Journal of Neuro-Oncology - Lower grade gliomas with 1p/19q codeletion are often responsive to chemotherapy, and several of these have been treated using upfront chemotherapy and subsequent...  相似文献   
969.
970.
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