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51.
《Médecine Nucléaire》2014,38(6):398-407
AimEvaluate 18-FDG PET/CT diagnostic and prognostic value before HIPEC.Materials and methodsThis retrospective monocentric study included 38 patients with recurrent (n = 27) or primary (n = 11) ovarian cancer who were blinded reviewed for the presence of peritoneal lesions on PET/CT before HIPEC treatment. The results were compared to surgical and histopathological findings, and to survival curves.ResultsThirty-two patients had peritoneal carcinomatosis based on surgical and histopathological findings, and 19 based on PET. There was no suspicious site of abnormal FGD uptake in the supradiaphragmatic regions. The sensitivity and specificity were respectively 56.2 and 100%. Among the 14 false negative patients, 11 had infracentimetric peritoneal implants, and most of them (n = 13) had chemotherapy before HIPEC. There was significantly more patients treated by chemotherapy in the negative PET group (P = 0.02). Even if the event rate observed was higher in the positive PET group for both event free and overall survival (respectively 68% vs. 64% and 26.3% vs. 17.6%), no significant difference was observed using the survival curves (respectively P = 0.62 and 0.59).ConclusionFDG PET/CT before HIPEC showed excellent specificity and lower sensitivity, due to small peritoneal implants and probably to chemotherapy before HIPEC. No significant prognostic value of FDG PET was observed in our study. FDG PET could be considered as a useful tool for detecting distant metastasis with an impact on therapeutic management.  相似文献   
52.
目的:采用N-三甲基壳聚糖包裹喜树碱(CPT-TMC)以增加其水溶性,并检测其抑制卵巢癌细胞淋巴结转移的效应。方法:体外实验,PI染色检测CPT-TMC促肿瘤细胞凋亡作用,体内实验,荷瘤裸鼠随机分为4组(5只/组):NS组、TMC组、CPT组及CPT-TMC组,通过尾静脉给药,每周2次,持续3周,Evan's Blue Dye染色,显影腹腔肿大转移的淋巴结。结果:PI染色提示CPT-TMC显著促进肿瘤细胞凋亡(P0.05);Evan's Blue Dye显影显示CPT-TMC显著抑制肿瘤细胞淋巴结转移(P0.05)。结论:CPT-TMC具有明显抑制卵巢癌细胞淋巴结转移效应,它可能成为一种新的有效的卵巢癌治疗药物。  相似文献   
53.
54.
《Cancer epidemiology》2014,38(4):455-459
Physical activity (PA) is related to colorectal cancer (CRC) mortality, with approximately 15% of CRC deaths worldwide attributable to physical inactivity. Moreover, higher levels of PA in CRC survivors have been associated with a reduced risk of the disease recurring. Despite the recognised nexus between PA and the risk of CRC, the physiological mechanisms underlying the inverse relationship between PA and mortality following CRC diagnosis are less apparent, with evidence primarily drawn from epidemiological studies. The insulin-like growth factor (IGF) axis plays a central role in cellular growth, proliferation regulation, differentiation and apoptosis. Specifically, high levels of insulin-like growth factor 1 (IGF-1) have been consistently linked to the severity of CRC tumours. Further, insulin-like growth factor binding protein 3 (IGFBP-3) regulates the bioavailability of IGF-I and therefore plays a central role in CRC prognosis. Decreasing levels of IGF-1 and increasing levels of IGFBP-3 may thus be a plausible mechanism underlying the inverse association between PA and CRC survival.  相似文献   
55.
目的:探讨卵巢高级别浆液性癌和低级别浆液性癌的差异表达蛋白,为阐明卵巢癌发生机制及寻找诊断和预后标志物的提供线索。方法:收集卵巢癌新鲜组织标本冻存于液氮中,经病理学确诊为高级别浆液性癌和低级别浆液性癌,两种类型各收集15例。应用i TRAQ定量蛋白质组学技术筛选及鉴定高/低级别浆液性癌的差异表达蛋白,并进行生物信息学分析。结果:卵巢高级别和低级别浆液性癌组织的定量蛋白质组学比较研究鉴定出差异表达蛋白314个,其中与低级别浆液性癌组比较,高级别浆液性癌组上调蛋白有97种,下调蛋白有217种。GO分析显示这些差异蛋白在分子功能、生物学功能、细胞成分方面均具有一定分布特点。KEGG分析显示这些差异蛋白涉及复杂的信号通路。结论:高/低级别浆液性癌之间存在差异表达蛋白,这些蛋白涉及复杂的功能和信号通路可能在两型卵巢癌发生机制及肿瘤生物学行为差异中具有重要意义。  相似文献   
56.
ObjectiveIn order to explore the predictive model for analyzing clinical pregnancy outcomes based on IVF-ET (in vitro fertilization and embryo transfer) and ICSI (Intracytoplasmic sperm injection) assisted reproductive technology (ART). Methods: this study selected the embryo transfer (fresh) patients who received IVF-ET or ICSI treatment in the First Affiliated Hospital of Guangxi Medical University as the subjects. Moreover, the controlled ovarian stimulation (COS) and follow-up were conducted to collect relevant data for analysis, and finally a prediction model was established. Results: The results showed that the patients were divided into different ovarian response groups at first. The age, bFSH and bFSH/bLH were the highest in the poor ovarian response group (POR), followed by the normal ovarian response group (NOR) and the lowest in the high ovarian response group (HOR). The area under the ROC curve was 0.669 according to the predictive model of pregnancy-related factors. The confidence interval of 94% was 0.629–0.697, with statistical significance (P = 0.000, P < 0.01). Conclusion: it can be concluded that in clinical pregnancy, for many related factors, regression equation can be used to establish a prediction model to diagnose the success rate of pregnancy. In conclusion, a prediction model can be built based on the relevant experimental results, to provide experimental reference ideas for increasing the success rate of ART in late clinical pregnancy, which is of great research significance.  相似文献   
57.
BackgroundOvarian cysts represent a common condition among women. Epidemiologic studies are inconsistent in determining if women with cysts are more likely to develop endometrial cancer (EC) regardless of overweight/obesity. We investigated the combined role of cysts and body mass index (BMI) on EC risk.MethodsWe pooled data from three case-control studies conducted in Italy and Switzerland on 920 women with EC and 1700 controls. The prevalence of cysts was 5% among both cases and controls, with 63% of cases being overweight/obese. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression models, adjusting for potential confounders. We conducted stratified analyses according to BMI, and estimated the interaction between cysts and BMI; we carried out additional analyses according to age at diagnosis of cysts.ResultsOverall, history of cysts was not associated to EC (OR=1.27, 95% CI=0.82–1.97, P = 0.29). Normal weight women reporting cysts had an increased risk of EC (OR=2.49, 95% CI=1.31–4.74), while no such effect was found among overweight/obese women (OR=0.65, 95% CI=0.36–1.18; P for interaction=0.004). The association was limited to women below 65 years of age and was stronger in those who reported cysts at age 48 or older.ConclusionsCysts appeared to be a risk factor for EC in lean women but not in overweight/obese ones; these results are consistent with an effect of cysts and obesity on EC along common pathways.  相似文献   
58.
Groups of photosensitive, unstimulated or stimulated, male blackheaded buntings were subjected to photoregimes of 15 hr of green light of three intensities and 9 hr of dark per day. In some groups green light was interrupted with 90 min of bright fluorescent light at different times in the subjective day. While gonads did not develop or regressed in some groups, birds in others behaved as if exposed to long daylengths. The results besides suggesting the involvement of endogenous circadian rhythm during initiation and maintenance of gonadal growth indicate that the reproductive rhythms are entrained and induced by environmental photoperiod.  相似文献   
59.
Cullin-RING ubiquitin ligases (CRLs) are the largest family of E3 ligases and require cullin neddylation for their activation. The NEDD8-activating enzyme inhibitor MLN4924 reportedly blocked cullin neddylation and inactivated CRLs, which resulted in apoptosis induction and tumor suppression. However, CRL roles in ovarian cancer cell survival and the ovarian tumor repressing effects of MLN4924 are unknown. We show here that CRL4 components are highly expressed in human epithelial ovarian cancer tissues. MLN4924-induced DNA damage, cell cycle arrest, and apoptosis in ovarian cancer cells in a time- and dose-dependent manner. In addition, MLN4924 sensitized ovarian cancer cells to other chemotherapeutic drug treatments. Depletion of CRL4 components Roc1/2, Cul4a, and DDB1 had inhibitory effects on ovarian cancer cells similar to MLN4924 treatment, which suggested that CRL4 inhibition contributed to the chemotherapeutic effect of MLN4924 in ovarian cancers. We also investigated for key CRL4 substrate adaptors required for ovarian cancer cells. Depleting Vprbp/Dcaf1 did not significantly affect ovarian cancer cell growth, even though it was expressed by ovarian cancer tissues. However, depleting Cdt2/Dcaf2 mimicked the pharmacological effects of MLN4924 and caused the accumulation of its substrate, CDT1, both in vitro and in vivo. MLN4924-induced DNA damage and apoptosis were partially rescued by Cdt1 depletion, suggesting that CRL4CDT2 repression and CDT1 accumulation were key biochemical events contributing to the genotoxic effects of MLN4924 in ovarian cancer cells. Taken together, these results indicate that CRL4CDT2 is a potential drug target in ovarian cancers and that MLN4924 may be an effective anticancer agent for targeted ovarian cancer therapy.  相似文献   
60.
Epithelial ovarian cancer is the most common form of gynaecological malignancy. This lethal disease is thought to arise in ovarian surface epithelial (OSE) cells. The biology of these cells is not well understood, due to the limited amount of tissue that can be obtained from a single biopsy and their limited life span in culture. To overcome these problems, we have conditionally immortalised OSE cells with the catalytic subunit of telomerase (hTERT) and a temperature-sensitive form of SV40 Large T antigen (tsT). We have maintained these cells (designated OSE-C2) in culture for more than 100 population doublings after introduction of the immortalising genes. Early passage OSE-C2 cells have a near-tetraploid karyotype and exhibit a dual mesenchymal-epithelial phenotype, with consistent expression of vimentin and variable expression of cytokeratins and type III collagen, and absence of E cadherin expression. OSE-C2 cells proliferate steadily at the permissive temperature of 33 degrees C, but fail to increase in number at the nonpermissive temperature of 39 degrees C. Serum-deprived OSE-C2 cells are stimulated to grow at 33 degrees C by EGF, whereas they are growth inhibited at 33 degrees C by TGFbeta in the presence or the absence of serum. When temperature shifted to the nonpermissive temperature, OSE-C2 cells modulate to a more mesenchymal phenotype, and a proportion of the cells undergo senescence and/or apoptosis. Moreover, at the nonpermissive temperature, the levels of p53 and SV40 Large T antigen diminish, whilst the level of p21 increases, whereas the level of p16 and telomerase activity is unchanged. This experimental system shows that expression of telomerase alone only allows limited proliferative potential of OSE cells; expression of tsT is necessary to maintain these cells in culture for longer periods, perhaps by its ability to inactivate components of the p53/Rb pathway. OSE-C2 cells may be useful in studying the physiology and differentiation of human OSE cells and provide insight into the poorly understood earliest stages of epithelial ovarian cancer.  相似文献   
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