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ObjectiveConsidering the difficulty in detecting primary breast cancers using whole-body positron emission tomography (WBPET) owing to its limited spatial resolution, we aimed to evaluate the detectability of breast cancer by ring-type dedicated breast PET (DbPET) on the World Health Organization (WHO) histological classification in comparison with WBPET.MethodsA total of 938 patients with breast cancer underwent WBPET and ring-type DbPET, and 1021 lesions were histologically assessed based on the WHO classification of tumors of the breast. The findings of WBPET and DbPET were retrospectively evaluated and compared.ResultsThe size-related sensitivity of DbPET was superior to that of WBPET for subcentimetric tumors (81.9% vs. 52.4%, P < 0.001). The histological distribution was as follows: 11 lobular carcinoma in situ, 158 ductal carcinoma in situ, 738 infiltrating duct carcinoma not otherwise specified (NOS), 12 lobular carcinoma NOS, 40 mucinous adenocarcinoma, 13 tubular carcinoma, 36 invasive breast carcinoma others, and 13 papillary neoplasms. WBPET had low sensitivity for lobular carcinoma in situ, ductal carcinoma in situ, lobular carcinoma NOS, mucinous adenocarcinoma, and tubular carcinoma. DbPET showed improved sensitivity for all the above except lobular and tubular carcinoma. The maximum standardized uptake values (SUVmax) of DbPET were significantly higher than those of WBPET for histological types, excluding lobular carcinoma in situ. The SUVmax of papillary neoplasms was high regardless of low-grade histology and Ki-67 labeling index.ConclusionsDBPET was found to have high sensitivity and SUVmax values for all histologic types that showed low sensitivity of detection on WBPET, except lobular carcinoma in situ.  相似文献   
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BackgroundBecause primary squamous cell carcinoma (SCC) of the breast is a rare disease, the standard therapy has not been established. We examined the clinical outcomes of postoperative adjuvant radiotherapy for breast SCC.Material and methodsWe conducted a multicenter retrospective cohort study. Patients diagnosed with primary breast SCC who received adjuvant radiotherapy as part of their primary definitive treatment were included. Overall survival (OS), breast cancer-specific survival (BCSS), and recurrence-free interval (RFi) were evaluated.ResultsBetween January 2002 and December 2017, 25 breast SCC patients received adjuvant radiotherapy as a primary treatment were included. Median follow-up time was 43.5 months. Three (12%), fifteen (60%) and seven (28%) patients had clinical stage I, II and III disease, respectively. Fourteen patients underwent breast-conserving surgery and subsequent adjuvant radiotherapy. Eleven patients underwent mastectomy and post-mastectomy radiotherapy. Ten patients received regional lymph node irradiation. Nine (36%) patients had disease recurrence. The first site of recurrence was locoregional in five, but distant metastasis arose in one. Concurrent local and distant metastasis were seen in two. Six cases of local recurrence occurred within the irradiated site. Seven patients died, and six of the deaths were due to breast cancer. Five-year OS, BCSS, and Rfi were 69%, 70%, and 63%, respectively. In multivariate analysis, age and lymphatic invasion were associated with increased risk of recurrence.ConclusionBreast SCC has a high incidence of locoregional recurrence and poor prognosis. Age and lymphatic invasion are significant risk factors for recurrence.  相似文献   
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目的基于癌症和肿瘤基因图谱(TCGA)和Kaplan-Meier Plotter数据库探讨G蛋白偶联雌激素受体(GPER)mRNA在乳腺癌组织中的表达及其与预后的关系。 方法本回顾性研究利用基因表达谱交互分析(GEPIA)工具下载含有乳腺癌患者GPER mRNA二代测序数据及临床病理资料的TCGA数据集,GPER mRNA表达为偏态分布数据,用[M(P25 ~P75 )]表示,采用Wilcoxon W检验分析1 085例乳腺癌组织样本和291例正常乳腺组织样本GPER mRNA表达的差异,同时用Kruskal-Wallis H检验分析乳腺癌组织中GPER mRNA表达与其临床病理特征的关系,两两比较用Bonferroni-Dunn检验。利用Kaplan-Meier Plotter数据库收集共3 951例乳腺癌患者的GPER mRNA表达情况,根据GPER mRNA表达的上下四分位数确定最佳截点值(103),从而将其分为GPER高、低表达2组,进而绘制无复发生存曲线,使用log-rank检验比较GPER高表达与低表达组的无复发生存率差异。 结果正常乳腺组织中GPER mRNA表达为6.247 9(6.022 4~6.554 6),乳腺癌组织中为5.700 4(5.357 6~6.022 0),差异有统计学意义(Z=-7.338,P<0.001)。不同T分期、N分期的乳腺癌组织中GPER mRNA表达比较,差异无统计学意义(χ2=3.343、6.084,P=0.488、0.193)。GPER mRNA在basal-like型、HER-2型、luminal型中的表达分别为-0.239 3(-0.250 7~-0.126 1)、-0.263 9(-0.275 9~-0.225 7)、-0.188 3(-0.239 7~-0.101 9),差异有统计学意义(χ2=106.187, P<0.001)。两两比较发现,HER-2型与basal-like型、HER-2型与luminal型、basal-like型与luminal型相比,GPER mRNA表达的差异均有统计学意义(P=0.019,P均<0.001)。GPER mRNA低表达患者的无复发生存率明显低于高表达患者(HR=0.67,95%CI:0.59~0.75,P<0.001)。 结论GPER mRNA低表达患者预后更差,提示GPER可能成为乳腺癌患者预后的独立预测因子。  相似文献   
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PurposePrevious studies have reported different methods of estrogen administration during endometrial preparation for frozen‐thawed embryo transfer (FET). This study aimed to investigate a beneficial regimen of transdermal estrogen administration for FET.MethodsWe investigated the reproductive and obstetric outcomes of FET by comparing the increasing dose (ID) group that mimics changes in serum estradiol during the menstrual cycle and the constant dose (CD) group. Transdermal patches were used for estrogen administration in both groups. In our hospital, we targeted 315 cycles of the ID group in which FET was performed in 2017 and 324 cycles of the CD group in which FET was performed in 2018. In all cases, single embryo transfer was performed.ResultsAll were singleton pregnancies. There was no difference in clinical pregnancy rate (28.9% vs 28.2%, P =.837) and live birth rate (17.3% vs 21.4%, P =.201) between the ID and CD groups. Spontaneous abortion rate was significantly lower in the CD group than in the ID group (37.2% vs 23.0%, P =.041). There was no difference in obstetrical outcomes.ConclusionsIt was considered that the simple CD regimen may be more beneficial than the complicated ID regimen.  相似文献   
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Bisphenol A (BPA), 4‐nonylphenol (NP) and butyl benzyl phthalate (BBP), termed endocrine‐disrupting chemicals, are known to mimic estrogen activity. The effects of these chemicals on 17β‐estradiol (E2) metabolism in vivo in rats were examined. Male and female rats were given NP (250 mg kg–1 day–1), BPA (250 μg kg–1 day–1) or BBP (500 mg kg–1 day–1) by gavage for 14 days, followed by a single intraperitoneal injection of E2 (5 mg kg–1) on the final day. The urinary excretion over 72 hours of 2‐hydroxyestrone 1‐N‐acetylcysteine thioether, 2‐hydroxyestrone 4‐N‐acetylcysteine thioether, 4‐hydroxyestrone 2‐N‐acetylcysteine thioether, 2‐hydroxy‐17β‐estradiol (2‐OHE2), 2‐hydroxyestrone (2‐OHE1), 4‐hydroxy‐17β‐estradiol, 4‐hydroxyestrone, 15α‐hydroxyestriol (E4), 15α‐hydroxy‐17β‐estradiol and 15α‐hydroxyestrone was measured. Increases in urinary excretion of 2‐OHE1 and decreases in E4 were observed in males treated with NP or BBP. Decreases in urinary excretion of 2‐OHE2 and E4 were observed in males treated with BPA. Decreases in urinary excretion of 2‐OHE1 and 2‐OHE2 were observed in females treated with BBP. Normalized liver and weights were increased in both sexes treated with NP or BBP. Histologic observations revealed marked changes in the distal tubules and collecting ducts in the kidneys of rats exposed to NP and BBP, and hypertrophy in the hepatocytes of the centrilobular zone of the liver. No BPA‐related effects on organ weight and on liver or kidney histopathology were found. These results suggest that the 14 day oral dosing of NP and BBP disrupted E2 metabolism, resulting from marked morphological and functional alterations in the liver and kidneys. In addition, BPA could induce metabolic and endocrine disruption.  相似文献   
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Field surveys of the impact of environmental estrogen (EE) pollution in aquatic wildlife have been conducted using vitellogenin (VTG) as a biomarker to evaluate the influence of EE. However, a standard baseline of VTG level that can be used to evaluate EE pollution has not been fully determined. To the best of our knowledge, the present study is the first to determine the standard baseline VTG level for evaluating the biological effects of EE pollution using the Japanese common goby (Acanthogobius flavimanus) as the target model fish. Plasma VTG and estradiol‐17β (E2) levels associated with the reproductive cycle of wild goby inhabiting an unpolluted environment were measured. Mean plasma VTG and E2 levels exhibited similar changes, increasing in the yolk vesicle stage and peaking in the tertiary yolk stage in females. However, plasma VTG and E2 levels showed no significant changes in males, remaining at low levels throughout the reproductive cycle. The highest VTG levels in females and males were 1.6 mg ml–1 and 124.87 ng ml–1, respectively. These results indicate that the baseline level (normal level) in males was approximately 130 ng ml–1 at most. We concluded that the threshold between normal and abnormal levels with a 10% risk rate was 150 ng ml–1 in the wild male goby. Plasma VTG levels in males captured from Nagasaki Harbor were higher than the threshold in each reproductive developmental stage, indicating the possibility of EE pollution at this site. The biological standard baseline for VTG established in this study is useful for assessing EE pollution in natural waters.  相似文献   
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The SLC22A18 gene, which encodes an orphan transporter, is located at the 11p15.5 imprinted region, an important tumor suppressor gene region. However, the role of SLC22A18 in tumor suppression remains unclear. Here, we investigated the involvement of SLC22A18 in cell growth, invasion, and drug resistance of MCF7 human breast cancer cell line. Western blot analysis indicated that SLC22A18 is predominantly expressed at intracellular organelle membranes. Quantitative proteomics showed that knockdown of SLC22A18 significantly altered the expression of 578 (31.0%) of 1867 proteins identified, including proteins related to malignancy and poor prognosis of breast cancer. SLC22A18 knockdown (1) increased MCF7 cell growth concomitantly with a >7-fold increase of annexin A8 (involved in cell growth and migration; a predictor of poor prognosis), (2) induced spherical morphology of MCF7 cells concomitantly with a nearly 3-fold increase of CD44 (involved in regulation of malignant phenotypes), and (3) increased chemosensitivity to vinca alkaloids concomitantly with a >80% reduction of doublecortin-like kinase 1 (involved in regulation of microtubule polymerization). Our results suggest that SLC22A18 may act as a tumor suppressor by regulating the expression levels of cell growth–related proteins, and vinca alkaloids might show therapeutic efficacy against low-SLC22A18–expressing breast cancer.  相似文献   
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