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1.
Endoscopic biopsies obtained from 275 patients (180 from the upper gastrointestinal tract and 95 from the lower gastrointestinal tract) were studied to compare the accuracy of biopsy imprint cytology and histology in the diagnosis of gastrointestinal lesions, and also to establish the degree of reliability of imprint cytology alone for an early diagnosis of malignancy. Biopsy histology results were found to be correct in 100% cases. Imprint cytology had an overall accuracy of 100%, 96.7%, 95.8% and 95.8% for the diagnosis of malignancies of the oesophagus, stomach, duodenum and colorectum respectively. False negative results were obtained with lymphomas. Regenerative cellular atypia was an important cause for false positive results. It was concluded that imprint cytology can serve as a useful and simple tool for an immediate diagnosis of malignancy. This should be subsequently correlated with histopathology which facilitates exact tumour typing and assessment of tumour invasion.  相似文献   
2.
An epiphrenic oesophageal diverticulum is most commonly a pulsion diverticulum which develops consequent to protrusion of mucosa through the muscular wall of the distal oesophagus. Most of them are associated with underlying oesophageal motility disorders. The predominant symptoms are dysphagia with regurgitation, and sometimes retrosternal pain, if accompanied by spasm of the oesophagus. Surgical management is recommended for symptomatic patients. Traditional procedures include thoracotomy or laparotomy with excision of the diverticula, but these are associated with high morbidity. Laparoscopic approach is a safe treatment option associated with lesser morbidity. Here, we present a case of epiphrenic diverticulum which was treated by the robotic approach without any complication. There was also no associated motility abnormality in our case so fundoplication was not done. Robotic surgery is a useful tool while operating near the hiatus and gastro-oesophageal junction. We consider transhiatal robotic approach as a safe and easy approach for surgery of epiphrenic diverticulum.  相似文献   
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Pelvic fractures carry a considerable risk for morbidity and mortality. Half or more of the early deaths in these patients have been attributed directly to haemorrhage. The transfusional requirements are four times higher for open pelvic fractures compared with a similar group of closed pelvic fractures. The loss of the tamponade effect by disruption of the pelvic soft tissues and the energy imparted play a central role in this potentially life threatening situation. We reported a case of open pelvic fracture in which persistent haemorrhage was stopped by giving recombinant activated coagulation factor VIIa as our last resort.  相似文献   
5.
BiVO4 is a promising photoanode material for the photoelectrochemical (PEC) oxidation of water; however, its poor charge transfer, transport, and slow surface catalytic activity limit the expected theoretical efficiency. Herein, we have investigated the effect of Mo doping on SnO2 buffer layer coated BiVO4 for PEC water splitting. SnO2 and Mo doped BiVO4 layers are coated with layer by layer deposition through a precursor solution based spin coating technique followed by annealing. At 5% doping of Mo, the sample (SBM5) shows a maximum current density of 1.65 mA cm−2 at 1.64 V vs. RHEl in 0.1 M phosphate buffer solution under AM 1.5 G solar simulator, which is about 154% improvement over the sample without Mo (SBM0). The significant improvement in the photocurrent upon Mo doping is due to the improvement of various bulk and interfacial properties in the materials as measured by UV-vis spectroscopy, electrochemical impedance spectroscopy (EIS), Mott–Schottky analysis, and open-circuit photovoltage (OCPV). The charge transfer kinetics at the BiVO4/electrolyte interface are investigated to simulate the oxygen evolution process in photoelectrochemical water oxidation in the feedback mode of scanning electrochemical microscopy (SECM) using 2 mM [Fe(CN)6]3− as the redox couple. SECM investigation reveals a significant improvement in effective hole transfer rate constant from 2.18 cm s−1 to 7.56 cm s−1 for the hole transfer reaction from the valence band of BiVO4 to [Fe(CN)6]4− to oxidize into [Fe(CN)6]3− with the Mo doping in BiVO4. Results suggest that Mo6+ doping facilitates the hole transfer and suppresses the back reaction. The synergistic effect of fast forward and backward conversion of Mo6+ to Mo5+ expected to facilitate the V5+ to V4+ which has an important step to improve the photocurrent.

BiVO4 is a promising photoanode material for the photoelectrochemical (PEC) oxidation of water; however, its poor charge transfer, transport, and slow surface catalytic activity limit the expected theoretical efficiency.  相似文献   
6.
The role of commensal bacterial microbiota in the pathogenesis of human malignancies has been a research field of incomparable progress in recent years. Although breast tissue is commonly assumed to be sterile, recent studies suggest that human breast tissue may contain a bacterial microbiota. In this study, we used an immune‐competent orthotopic breast cancer mouse model to explore the existence of a unique and independent bacterial microbiota in breast tumors. We observed some similarities in breast cancer microbiota with skin; however, breast tumor microbiota was mainly enriched with Gram‐negative bacteria, serving as a primary source of lipopolysaccharide (LPS). In addition, dextran sulfate sodium (DSS) treatment in late‐stage tumor lesions increased LPS levels in the breast tissue environment. We also discovered an increased expression of S100A7 and low level of TLR4 in late‐stage tumors with or without DSS as compared to early‐stage tumor lesions. The treatment of breast cancer cells with LPS increased the expression of S100A7 in breast cancer cells in vitro. Furthermore, S100A7 overexpression downregulated TLR4 and upregulated RAGE expression in breast cancer cells. Analysis of human breast cancer samples also highlighted the inverse correlation between S100A7 and TLR4 expression. Overall, these findings suggest that the commensal microbiota of breast tissue may enhance breast tumor burden through a novel LPS/S100A7/TLR4/RAGE signaling axis.  相似文献   
7.
Additional prognostic and therapeutic biomarkers effective across different histological types of sarcoma are needed. Herein we evaluate expression of TAZ and YAP, the p53-MDM2 axis, and RABL6A, a novel oncoprotein with potential ties to both pathways, in sarcomas of different histological types. Immunohistochemical staining of a tissue microarray including 163 sarcomas and correlation with clinical data showed that elevated YAP and TAZ independently predict worse overall and progression-free survival, respectively. In the absence of p53 expression, combined TAZ and YAP expression adversely affect overall, progression free, and metastasis free survival more than TAZ or YAP activation alone. RABL6A independently predicted shorter time to metastasis and was positively correlated with p53, MDM2 and YAP expression, supporting a possible functional relationship between the biomarkers. Network analysis further showed that TAZ is positively correlated with MDM2 expression. The data implicate all five proteins as clinically relevant downstream players in the Hippo pathway. Finally, a novel inhibitor of MDM2 (MA242), effectively suppressed the survival of sarcoma cell lines from different histological types regardless of p53 status. These findings suggest both independent and cooperative roles for all five biomarkers across different histological types of sarcoma in predicting patient outcomes and potentially guiding future therapeutic approaches.  相似文献   
8.
Time resolved particle image velocimetry was used to measure wall shear stress (WSS) and oscillatory shear index (OSI) within a 3.0 mm diameter compliant vessel model implanted with an Abbott Vascular XIENCE V® stent in five configurations: baseline, over-expanded, increased vessel diameter, two overlapped stents, and increased stent length. Flow through unstented vessels was also tested for comparison. Flow conditions featured a realistic coronary pressure-flow offset and reversal at average flow rates corresponding to resting (Re = 160, f = 70 bpm) and exercise conditions (Re = 300, f = 120 bpm). Comparisons revealed that the WSS was similar for all cases behind the first strut and downstream of the device, indicating that changes in configuration have little effect downstream. However, there were notable differences within each stent revealing reduced WSS values for all cases due to the stent-imposed expansion of the vessel wall (0.20–9.29 dynes/cm2 for Re = 160 and d = 3.0 mm). Over-expanding the stent with a second balloon affected the alignment of the stent geometry, and led to higher WSS at the inlet and lower values at mid-stent. The overlapped stents showed disturbed flow and a WSS deficit region downstream of the overlapped region. Analysis of the longer stent showed that the WSS within the vessel recovers with distance. An overall correlation was noted between decreased WSS values and elevated OSI. Results of this study are important because decreased WSS has been implicated in endothelial cell changes and increased restenosis, and clinical research has shown that a link exists between deployment configurations and negative patient outcomes.  相似文献   
9.
Dental caries is a bacterial infectious disease characterized by demineralization of the tooth enamel. Treatment of this disease with conventional antibiotics is largely ineffective as the cariogenic bacteria form tenacious biofilms that are resistant to such treatments. The main etiological agent for dental caries is the bacterium Streptococcus mutans. S. mutans readily forms biofilms on the tooth surface and rapidly produces lactic acid from dietary sucrose. Glucosyl transferases (Gtfs) secreted by S. mutans are mainly responsible for the production of exopolysaccharides that are crucial for the biofilm architecture. Thus, inhibiting S. mutans’ Gtfs is an effective approach to develop selective biofilm inhibitors that do not affect the growth of oral commensals. Herein, we report a library of 90 analogs of the previously identified lead compound, G43, and exploration of its structure activity relationships (SAR). All compounds were evaluated for the inhibition of S. mutans biofilms and bacterial growth. Selected compounds from this library were further evaluated for enzyme inhibition against Gtfs using a zymogram assay and for growth inhibition against oral commensal bacterial species such as Streptococcus gordonii and Streptococcus sanguinis. This study has led to the discovery of several new biofilm inhibitors with enhanced potency and selectivity. One of the leads, IIIF1, showed marked reduction in buccal, sulcal, and proximal caries scores in a rat model of dental caries.  相似文献   
10.
ObjectiveTo evaluate antidiabetic activity of chloroform extracts of Acacia arabica bark, Benincasa hispida fruit, Tinispora cordifolia stem, Ocimum sanctum areal parts and Jatropha curcus leaves.MethodsThe chloroform extracts of Acacia arabica bark, Benincasa hispida fruit, Tinospora cordifolia stem, aerial part of Ocimum sanctum and Jatropha curcus leaves were evaluated at different doses (250 and 500 mg/kg body weight.) for antidiabetic potentials in alloxan induced diabetic albino rats. The extracts were administered for two weeks in different groups whereas tolbutamide (80 mg/kg body weight) was used as reference standard throughout study.ResultsThe result of present study showed test compounds significantly decreases elevated level of serum glucose and also caused to reverse the cholesterol, triglyceride, HDL and LDL values when compared to untreated diabetic rats.ConclusionsOur finding indicates that different test extracts were able to ameliorate the derangements in lipid metabolism caused by diabetes mellitus in alloxan induced diabetic rats towards normal level.  相似文献   
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