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991.
Our study attempted to assess the possible induction and persistence of an adaptive response in lymphocytes of thyroidectomized thyroid cancer patients treated with 131I (2,590 MBq, corresponding to whole body doses in the range of 200-300 mGy), to a testing dose of mitomycin C (MMC) in vitro. The cytogenetic endpoint studied was the induction of micronuclei in cytokinesis-blocked peripheral blood lymphocytes, immediately before treatment and 1, 6 and 24 months after therapy. One month after therapy, induction of micronucleated cytokinesis-blocked lymphocytes ( per thousand ) by MMC was lower (34.6 +/- 7.7) than before therapy (52.1 +/- 5.0). In 7 of 11 patients this reduction was significant. However, at 6 months, induction of micronuclei was markedly higher (133.1 +/- 13.6). This significant increase was observed regardless of the decrease at 1 month. At 24 months, the frequency of micronucleated cells decreased (84.8 +/- 5.5), but remained higher than before treatment. The results obtained 1 month after therapy could reflect adaptation due to radiation, or a higher rate of early apoptosis or cell death, with bone marrow suppression, visible as a lower response in vitro towards MMC. At 6 months, recovery of the lymphocyte population may occur, and higher responses to MMC in vitro could reflect higher chromosomal instability in the previously irradiated stem cells with a concomitant disappearance of adaptation, whereas at 24 months the results show a tendency to return to pretherapy values.  相似文献   
992.
AIMS AND BACKGROUND: Carcinoembryonic antigen (CEA) belongs to a family of cell surface glycoproteins. Its level in serum has a significant value for the follow-up and treatment of patients with malignancies. The aim of this study was to correlate the concentration of tumor cytosol CEA (cCEA) with tumor size, patient age and sex, clinical stage, lymph node metastases, and overall survival rate in primary non-small cell lung carcinoma (NSCLC). METHODS AND STUDY DESIGN: The cCEA levels were determined in 76 NSCLC patients by luminescence assay (LIA) and radioimmunoassay (RIA). RESULTS: A strong correlation between LIA and RIA assay results was found (r = 0.992). No correlation was observed between serum CEA and cCEA levels. Tumors smaller than 3 cm had significantly higher cCEA levels than larger tumors, but when a logistic modeling process was applied this difference was not significant (P = 0.038). Histologically well-differentiated tumors also showed a significantly higher expression of cCEA (P <0.05). In addition, patients without lymph node involvement had higher cCEA levels than patients with tumor-positive lymph nodes (P < 0.05). Univariate statistical analysis revealed that the risk of lymph node metastases was 1.8-fold higher in patients with low cCEA levels than in patients with higher levels, taking the median value as cutoff (P = 0.04, Kruskal-Wallis test). CONCLUSIONS: According to the results of our study, patients with overexpression of cCEA may have a better prognosis than those with low cCEA expression. cCEA might therefore be considered a good prognostic parameter as well as a prognostic factor independent of the traditional parameters for lymph node metastases.  相似文献   
993.
Fusion proteins created by chromosomal abnormalities are key components of mesenchymal cancer development. The most common chromosomal translocation in liposarcomas, t(12;16)(q13;p11), creates the FUS-CHOP fusion gene. In the past, we generated FUS-CHOP and CHOP transgenic mice and have shown that while FUS-CHOP transgenic develop liposarcomas, mice expressing CHOP, which lacks the FUS domain, display essentially normal white adipose tissue (WAT) development, suggesting that the FUS domain of FUS-CHOP plays a specific and critical role in the pathogenesis of liposarcoma. To test the significance of FUS and CHOP domain interactions within a living mouse, we generated mice expressing the FUS domain and crossed them with CHOP-transgenic mice to generate double-transgenic FUSxCHOP animals. Here we report that expression of the FUS domain restores liposarcoma development in CHOP-transgenic mice. Our results provide genetic evidence that FUS and CHOP domains function in trans for the mutual restoration of liposarcoma. These results identify a new mechanism of tumor-associated fusion genes and might have impact beyond myxoid liposarcoma.  相似文献   
994.
Objective: We examined prospectively intakes of vitamins A, C, and E, folate, and specific carotenoids in relation to the risk of basal cell carcinoma of the skin (BCC) in women. Methods: Dietary intake was assessed by food-frequency questionnaires every two–four years and the first diagnosis of BCC was ascertained by self-report every two years. We used logistic regression to model the association between dietary intake and the risk of BCC adjusting for various health, sun exposure, and sun sensitivity factors. Results: During 12 years of follow-up we recorded 5392 cases. We did not find any significant inverse associations between these dietary factors and BCC. On the contrary, weak positive trends were seen with vitamins A, C, and E, and folate. The multivariate relative risks (RRs) comparing the top to bottom quintile were 1.20 (95% CI = 1.10–1.31) for folate, 1.16 (95% CI = 1.06–1.26) for vitamin A, 1.13 (95% CI = 1.03–1.23) for vitamin C, and 1.15 (95% CI = 1.06–1.26) for vitamin E. Exploration of latency periods did not suggest different associations with a particular duration. Conclusions: We did not find evidence that vitamins A, C, and E, and folate, or specific carotenoids play an important protective role against the incidence of BCC.  相似文献   
995.
Interleukin-6 (IL-6) plays a pathogenetic role in B-cell malignancies and is a growth factor for multiple myeloma (MM) cells. Elevated serum IL-6 levels and a higher proliferative activity of bone marrow plasma cells are poor prognostic factors in MM patients. In addition to clinical trials with anti-IL-6 monoclonal antibodies, an alternative therapeutic approach based on the use of IL-6 receptor (R) super-antagonists (Sants) has been proposed. Sants are variants of the native cytokine characterized by a wild type affinity for the ligand-specific receptor chain IL-6R alpha and by a reduced ability to bind and/or dimerize the signaling chain gp-130. We report the in vitro effects of four different Sants on cell kinetic modulation and induction of apoptosis of primary cells from MM patients. Ten MM samples were cultured in the presence of four different Sants and heterogeneous effects in terms of reduction of proliferation and induction of apoptosis could be observed. A decrease of the S phase cells (> or = 25%) coupled with the induction of apoptosis was obtained in 4/10 samples: three of these samples had a diploid DNA stem line and an inferior initial percentage of S phase cells. Serum IL-6 concentrations did not correlate with the anti-proliferative activities of the Sants. Cell growth inhibition was observed especially in samples with soluble IL-6R serum concentrations > 200 ng/ml. We conclude that Sants can exert antiproliferative effects on selected MM samples. Such effects may depend on the availability of large amounts of soluble IL-6R. Further studies should aim at defining the conditions necessary for optimal antiproliferative activity.  相似文献   
996.
Evidence is accumulating for physical activity as an effective, well-tolerated, highly rewarding complementary behavioral intervention for enhancing quality of life (QOL) as well as fitness among individuals with chronic and even terminal illnesses. However, relatively few studies have examined the feasibility and potential health benefits of supervised, structured exercise programs for sedentary women with primary breast cancer. Forty women over the age of 45 with primary breast cancer participated in a course of group exercise training (GET) delivered in a structured format three times per week for 16 weeks. GET emphasizes physical activities that promote aerobic fitness, strength, and flexibility. Assessments of fitness/vigor and QOL were conducted prior to, during, and upon completion of the program. Results demonstrated that GET was feasible, safe, and well-tolerated. Moreover, the participants experienced significant health benefits over the course of the intervention in multiple dimensions of fitness/vigor (aerobic capacity, strength, flexibility) as well as QOL (increased positive affect, decreased distress, enhanced well-being, and improved functioning). Discussion highlights the need for inclusion of physical activity programs in comprehensive, complementary treatment regimes for breast cancer patients.  相似文献   
997.
Oncogenic activation of the RET receptor tyrosine kinase is common in different human cancers. We found that the pyrazolo-pyrimidine PP1 inhibited RET-derived oncoproteins with a half maximal inhibitor concentration of 80 nM. Furthermore, RET/PTC3-transformed cells treated with 5 microM of PP1 lost proliferative autonomy and showed morphological reversion. PP1 prevented the growth of two human papillary thyroid carcinoma cell lines that carry spontaneous RET/PTC1 rearrangements and blocked anchorage-independent growth and tumorigenicity in nude mice of NIH3T3 fibroblasts expressing the RET/PTC3 oncogene. These findings suggest targeting RET oncogenes with PP1 or related compounds as a novel treatment strategy for RET-associated neoplasms.  相似文献   
998.
BACKGROUND AND AIM: In vitro, methotrexate (MTX) is the best modulator for bolus 5-fluorouracil (5FU), whereas folinic acid (FA) is the best for continuous infusion. We evaluated the effect of 5FU modulated by both MTX (bolus administration) and FA (continuous infusion) as second-line treatment of patients with metastatic colorectal cancer. PATIENTS AND METHODS: Entry criteria were: at least one 5FU-based chemotherapy regimen as first-line treatment for metastatic disease, or progression within twelve months after 5FU-containing adjuvant therapy. Treatment schedule: MTX 200 mg/m2 i.v. days 1 and 15; 5FU 600 mg/m2 i.v. bolus, days 2 and 16; 5FU 200 mg/m2 i.v. continuous infusion for 21 days, starting on day 29; FA 20 mg/m2 i.v. bolus weekly during the three weeks of 5FU infusion. Cycles were repeated every 56 days. The primary end-point was tumour control rate, including partial responses and stabilizations. RESULTS: 34/35 patients enrolled were evaluable for response. Five (14.7%) had a partial response, 13 (38.2%) disease stabilization, and 16 (47.1%) progressed; tumour control rate was 52.9%. Median TTP was 5.8 months (95% CI 4.03-7.83); 29 patients had died. Median OAS was 15.9 months (95% CI 8.8-21.9). Toxicity was mild. CONCLUSIONS: The regimen constituted by 5FU modulated by MTX (bolus administration) and FA (continuous infusion) is active as second-line treatment of metastatic colorectal cancer.  相似文献   
999.
PURPOSE: We report the case of a male newborn with Ohtahara syndrome and right hemimegalencephaly who presented epileptic negative myoclonus in the first days of life. METHODS: Prolonged polygraphic studies were performed, as well as MRI and a full clinical examination. RESULTS: EEG showed a constant and nonreactive pattern of burst suppression. There were several kinds of electro-clinical seizures (generalized myoclonia, short atonias, typical spasm and tonic spasms) at the beginning of the EEG's burst. The periods of EMG silence, lasting less than 300 ms, were associated with stereotyped EEG transients. CONCLUSIONS: Epileptic negative myoclonus can be observed also in neonatal age. The short transient impairment of motor function observed in the newborn seems linked to the slow component of spike-wave discharge, but its mechanism is still not clear.  相似文献   
1000.
Twenty-four autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) probands were analyzed for the presence of V287L and V287M mutations in the CHRNB2 gene, which have been recently associated with the disease. In all patients, the involvement of the two additional loci reported as being associated with ADNFLE (CHRNA4 gene and chromosome 15q24 region) had been previously excluded. Mutational screening was performed by sequencing a polymerase chain reaction-amplified CHRNB2 DNA fragment, spanning the whole exon 5, which contains the V287L and V287M mutations and codes for approximately 65% of the mature protein. In none of the patients were mutations in the analyzed region of CHRNB2 found. These data, obtained in the largest ADNFLE cohort so far analyzed, demonstrate the rarity of the identified CHRNB2 mutations in ADNFLE patients.  相似文献   
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