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991.
1-Methyl-4-phenylpyridinium ion (MPP+) has been shown to selectively inhibit mitochondrial function and induce a parkinsonism-like syndrome. MPP+ stimulates the production of reactive oxygen species (ROS) and induces cell death in vitro. In this study, we investigated the protective effects of okadaic acid on MPP+-induced cell death in SH-SY5Y neuroblastoma cells. We found that MPP+-induced apoptosis and -ROS generation were blocked by okadaic acid. MPP+-mediated activation of AKT was also inhibited by okadaic acid. Taken together, these results demonstrate that okadaic acid protects against MPP+-induced apoptosis by blocking ROS stimulation and ROS-mediated signaling pathways in SH-SY5Y cells. These data indicated that okadaic acid could provide a therapeutic strategy for the treatment of neurodegenerative diseases including Parkinson's disease.  相似文献   
992.
Introduction  Massive intracranial hemorrhage is a very rare initial presentation of cerebellar pilocytic astrocytomas. There are no reports in the medical literature on a cerebellar pilocytic astrocytoma presenting with intratumor bleeding (ITB), subarachnoid hemorrhage (SAH), and subdural hematoma (SDH). Case report  A 15-month-old boy presented with lethargy and nausea to our hospital. Magnetic resonance imaging showed a mass with ITB at the left cerebellar hemisphere in addition to SDH in the posterior fossa and SAH at the interpeduncular cistern. The patient underwent emergency surgery. On incising the dura, we found SDH, the tumor was visible at the cerebellar cortex, and near total removal followed. Microscopic examination of tissue sections revealed a pilocytic astrocytoma. Discussion  The authors’ case is the first report with a presentation including ITB, SAH, and SDH. The presumed mechanism of the SAH and SDH was leaking of the ITB into subarachnoid and subdural spaces.  相似文献   
993.
Bee venom (BV) treatment is the therapeutic application of honeybee venom (HBV) for treating various diseases in Oriental medicine. In the present work, the authors investigated the functional specificity of BV as an angiogenesis inhibitor using in vitro models and in vivo mouse angiogenesis and lung metastasis models. BV significantly inhibited the viability of Lewis lung carcinoma (LLC) cells but did not affect peripheral blood mononuclear lymphocytes (PBML) cells. BV also inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration and capillary-like tube formation of human umbilical vein endothelial cells (HUVECs). Western blotting analysis showed that BV inhibited AKT and MAPK phosphorylation in LLC cells and HUVECs and down regulated expression of VEGF and VEGFR-2 of LLC cells and HUVECs. Also, BV effectively disrupted VEGF-induced neovascularization in Matrigel plugs in our in vivo angiogenesis assay. When given subcutaneously, BV also significantly suppressed tumor angiogenesis through inhibition of VEGF and VEGFR-2 in LLC model. Mice bearing subcutaneous LLC tumors were treated with 1 μg/ml or 10 μg/ml of BV. They showed reductions ranging between 49% and 62% in primary tumor volume and reduction of spontaneous pulmonary metastasis occurrences. Furthermore, BV treatment in the spontaneous lung metastases model after primary tumor excision prolonged their median survival time from 27 to 58 days. These results suggest that the tumor-specific anti-angiogenic activity of BV takes effect during different stages of tumor progression by blocking the tyrosine phosphorylation of VEGFR-2, and validate the application of BV in lung cancer treatment.  相似文献   
994.
Anastomotic leakage (AL) is one of the most serious complications of colorectal surgery. It can affect long-term oncologic outcomes, but the impact on long-term survival remains uncertain. The aim of this study is to evaluate the operative characteristics of leakage and no leakage groups and to analyze long-term oncologic outcomes.We prospectively enrolled 10,477 patients from 2000 to 2011 and retrospectively reviewed the data.Male sex (odds ratio [OR], 3.90; P < 0.001), intraoperative transfusion (OR, 2.31; P = 0.042), and operative time (OR, 1.73; P = 0.032) were independent risk factors of AL in the colon. In the rectum, male sex (OR, 2.37; P < 0.001), neoadjuvant chemoradiotherapy (OR, 2.26; P < 0.001), and regional lymph node metastasis (OR, 1.43; P = 0.012) were independent risk factors of AL, and diverting stoma (OR, 0.24; P < 0.001) was associated with a deceased risk of AL. AL in the rectum without a diverting stoma was associated with disease-free survival (DFS, OR, 1.47; P = 0.037). Colonic leakage was not associated with 5-year DFS (leakage group vs nonleakage group, 72.4% vs 80.9%, P = 0.084); however, in patients undergoing rectal resection, there was a significant difference in 5-year DFS (67.0% vs 76.6%, P = 0.005, respectively).AL in the rectum is associated with worse long-term DFS and overall survival. A diverting stoma was shown to protect against this effect and was associated with long-term survival in rectal surgery. Therefore, creating a diverting stoma should be considered in high-risk patients undergoing rectal surgery.  相似文献   
995.
Radiotherapy is commonly offered to patients with pancreatic malignancies although its ultimate utility is compromised since the pancreas is surrounded by exquisitely radiosensitive normal tissues, such as the duodenum, stomach, jejunum, liver, and kidneys. Proton radiotherapy can be used to create dose distributions that conform to tumor targets with significant normal tissue sparing. Because of this, protons appear to represent a superior modality for radiotherapy delivery to patients with unresectable tumors and those receiving postoperative radiotherapy. A particularly exciting opportunity for protons also exists for patients with resectable and marginally resectable disease. In this paper, we review the current literature on proton therapy for pancreatic cancer and discuss scenarios wherein the improvement in the therapeutic index with protons may have the potential to change the management paradigm for this malignancy.  相似文献   
996.

Purpose

Methylenetetrahydrofolate reductase (MTHFR) is the main regulatory enzyme for homocysteine metabolism. In the present study, we evaluated whether the MTHFR 677C>T and 1298A>C gene polymorphisms are associated with SBI and plasma homocysteine concentration in a Korean population.

Materials and Methods

We enrolled 264 patients with SBI and 234 healthy controls in South Korea. Fasting plasma total homocysteine (tHcy) concentrations were measured, and genotype analysis of the MTHFR gene was carried out.

Results

The plasma tHcy levels were significantly higher in patients with SBI than in healthy controls. Despite a significant association between the MTHFR 677TT genotype and hyperhomocysteinemia, the MTHFR 677C>T genotypes did not appear to influence susceptibility to SBI. However, odds ratios of the 1298AC and 1298AC + CC genotypes for the 1298AA genotype were significantly different between SBI patients and normal controls. The frequencies of 677C-1298A and 677C-1298C haplotypes were significantly higher in the SBI group than in the control group.

Conclusion

This study demonstrates that the MTHFR 1298A>C polymorphism is a risk factor for SBI in a Korean population. The genotypes of 677C>T and 1298A>C polymorphisms interact additively, and increase the risk of SBI in Korean subjects.  相似文献   
997.
Translocation (10;17)(p13-15;q12-21) in acute leukemia is rarely reported in the literature. Here, we present both a novel t(10;17) case study and a review of relevant literature on t(10;17) in acute leukemia (10 cases). In summary, we came to the following preliminary conclusions: t(10;17) is associated with poorly differentiated acute leukemia subtype [90%; eight cases of acute myeloid leukemia (AML M0, M1) and one case of acute undifferentiated leukemia], phagocytic activity by blasts occurs (30%), and the survival time was short in three of the seven t(10;17) cases for whom follow-up data were available (median, 8 months). More clinical studies concerning the prognosis, treatment response, and survival of patients with t(10;17) are necessary.  相似文献   
998.
Deletion of the long arm of chromosome 20 is a common abnormality associated with myeloid malignancies. We characterized abnormalities of chromosome 20 as defined by metaphase cytogenetics (MC) in patients with myeloid neoplasms to define commonly deleted regions (CDR) and commonly retained regions (CRR) using genome‐wide, high resolution single nucleotide polymorphism array (SNP‐A) analysis. We reviewed the MC results of a cohort of 1,162 patients with myeloid malignancies, including myelodysplastic syndromes (MDS), MDS/myeloproliferative neoplasia (MDS/MPN), and acute myeloid leukemia (AML). We further analyzed a subcohort of 532 patients by SNP‐A using the Affymetrix Genome‐Wide Human SNP Array 6.0 and GeneChip Human Mapping 250K Nsp arrays. By MC, 5% (54/1,162) harbored a deletion of 20q; in 30% (16/54), del(20q) was the sole cytogenetic abnormality. By SNP‐A analysis, we identified del(20q) in 23 patients, 3 not detected by MC. In four cases, monosomy 20 with a marker chromosome by MC was proven to be an interstitial deletion of 20q by SNP‐A. We defined 2 CDR and 2 CRR on chromosome arm 20q: CDR1 spanned 2.5 Mb between bands 20q11.23 and 20q12, while CDR2 encompassed 1.8 Mb within 20q13.12. CRR1 spanned 1.9 Mb within 20q11.21 and CRR2 encompassed 2.5 Mb within 20q13.33. In contrast to other chromosomes frequently affected by deletions, no somatic copy neutral loss of heterozygosity (CN‐LOH) was detected. Our data suggest that SNP‐A is useful for the detection of cryptic aberrations of chromosome 20q and allows for a more precise characterization of complex karyotypes. Furthermore, SNP‐A allowed definition of a CDR on 20q. © 2010 Wiley‐Liss, Inc.  相似文献   
999.
Carcinosarcoma of the ovary-a case series   总被引:2,自引:0,他引:2  
OBJECTIVE: To evaluate our experience with ovarian carcinosarcoma and identify prognostic factors. METHODS: Thirty-one cases of ovarian carcinosarcoma were identified over a 6-year time period through tumor registry and pathology records. Fisher exact test and log rank using Kaplan-Meier method (P < 0.05) were used to compare variables with outcome. RESULTS: All 31 patients underwent initial surgical treatment with an appropriate staging procedure. Stage distribution: 1 stage I, 6 stage II, 23 stage III, and 1 stage IV. The median follow-up was 28 months. The median survival for the entire group was 21 months. Early vs. advanced stage significantly influenced progression-free interval, P = 0.05. Nineteen patients were found to have stage IIIC disease and required debulking procedures. In patients with stage IIIC disease, presence of residual disease was associated with decreased overall survival, P = 0.03. 29 patients received adjuvant chemotherapy with 11 patients receiving ifosfamide/cisplatin and 16 patients receiving carboplatin/taxol. Progression-free interval was improved with the use of ifosfamide/cisplatin vs. carboplatin/taxol. The median PFI was 12 months in the carbo/taxol group and has not been reached in the ifos/cisplatin group (P = 0.005). The overall survival was also significantly improved with the use of ifosfamide/cisplatin, P = 0.03. In advanced stage patients, overall survival was not significantly influenced by type of adjuvant chemotherapy administered, P = 0.13. CONCLUSIONS: Ovarian carcinosarcoma has a poor overall prognosis with median survival rates reported in the literature ranging from 7-10 months. Our series, although limited by a small number of patients, exhibits a more encouraging median survival of 21 months for the overall group. Aggressive debulking to eliminate residual disease and the use of ifosfamide/cisplatin chemotherapy seem to be factors in this improved outcome.  相似文献   
1000.
OBJECTIVE: To prospectively evaluate in a blinded fashion the accuracy of frozen section in endometrial cancer. METHODS: Sixty patients with endometrial cancer or complex atypical hyperplasia were consecutively enrolled. Intraoperatively, a frozen section was obtained, processed, and stored for interpretation by blinded pathologists. Final pathologic diagnosis was conducted in the usual fashion with the pathologists blinded to frozen results. Histologic grade and myometrial invasion on frozen section was correlated with final pathology. RESULTS: Median age was 61 years (range, 39-82 years). Fifty-seven percent of patients were white, and mean body mass index was 40 mg/kg2. Depth of invasion on frozen correlated with final pathology in 67% (95% confidence interval [CI] 55-79%). Twenty-eight percent (95% CI 17-39%) of patients were upstaged from frozen to final. Patients with no invasion on frozen were upstaged in 46% (95% CI 28-64%). Histologic grade on frozen correlated with final pathology in 58% (95% CI 46-70%); 38% (95% CI 26-50%) of patients were upgraded by final grade. Patients with frozen grade 1 histology or less were upgraded in 61% (95% CI 45-77%). Clinically relevant upstaging occurred in 11 patients (18%) (95% CI 8-28%). CONCLUSION: Frozen section for histologic grade and depth of myometrial invasion in endometrial cancer correlates poorly with final pathology. Because a large number of patients are potentially understaged with the use of frozen section with a subsequent risk of over and under treatment, we recommend consideration of comprehensive surgical staging for all patients with endometrial cancer. LEVEL OF EVIDENCE: II-2.  相似文献   
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