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1.
The BALB/3T3 mouse embryo cell line, noted for its marked postconfluence inhibition of proliferation, anchorage dependence, and high serum requirement, and frequently studied as a prototype nontumorigenic "fibroblast" line that is compared with tumorigenic sublines transformed with various agents, produced tumors within 2 to 3 months when an average of 3 X 10(4) cells were implanted s.c. attached to 1- X 5- X 10-mm polycarbonate platelets. Plastic platelets alone produced no tumors after 1 year of observation. The tumors, as well as others arising from implants of BALB/3T3 cells attached to 3-mm glass beads, were given the histological diagnosis of "vasoformative saroma" because the tumor cells frequently formed vascular channels. The vasoformative pattern and the results of specific staining for reticulin and collagen support the likelihood that BALB/3T3 cells originated from endothelial cells rather than from fibroblasts. That the tumors were derived from BALB/3T3 cells and not host cells was proved when tumors arising in BALB/c X C57BL/6 F1 hybrids were shown to be transplantable to BALB/c but not to C57BL/6 mice. The cultured tumor cells showed loss of both postconfluence inhibition of proliferation and anchorage dependence. Evidence of the induction of endogenous oncornaviruses was obtained in only one of four tumors tested. These tumors also exhibited tumor-unique transplantation rejection antigens. We conclude that BALB/3T3 cells are preneoplastic and give rise to different spontaneously transformed clones bearing unique tumor rejection antigens when implanted in vivo attached to a solid substrate.  相似文献   
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The objective of this observational study was to quantify the incidence of urinary tract infections (UTI) among diabetes patients and compare this risk to patients without diabetes. Type 2 diabetes patients and a matched sample of patients without diabetes were identified from GPRD. Patients were followed for 1-year from their study index date until the first record of a UTI or a censored event. The incidence of UTI was 46.9 per 1000 person-years (95% confidence interval (CI) 45.8–48.1) among diabetes patients and 29.9 (95% CI 28.9–30.8) for patients without diabetes. Compared to the non-diabetes patients, the risk of UTI was 1.53 (95% CI 1.46–1.59) for all diabetes patients; and 2.08 (95% CI 1.93–2.24) for patients with previously diagnosed diabetes. In general practice, across gender and age, the risk of developing a UTI is higher for patients with type 2 diabetes compared to patients without diabetes.  相似文献   
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Nutrition therapy is an essential aspect of patient care and an important determinant of outcomes in the ICU. Nutrition can impact respiratory function in a myriad of ways. Under- and overfeeding are two well-established ways by which nutrition impinges on respiratory function. Route of feeding, method of feeding, and carbohydrate composition of the diet are also other key factors regarding nutrition that influence outcomes in ICU patients. Recent studies are now elucidating the role of immune therapy in patients with acute respiratory distress syndrome. In the ICU, nutrition dogmas, such as the necessity of checking gastric residual volumes or utilizing full-calorie enteric feeds, as opposed to trophic feeds, are constantly being challenged by innovative clinical studies. Basic research brings the prospect of testing new approaches for ICU patients, such as the use of antioxidants to prevent diaphragm weakness in these patients. In this review article, we evaluate the recent observational and randomized control trials to critically appraise the evidence regarding nutrition in the ICU.  相似文献   
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As procedures such as epicardial ventricular ablation and left atrial appendage occlusion become more commonplace, the need grows for safer techniques to access the physiologic pericardial space. Because this space contains minimal fluid for lubrication, prevailing methods of pericardial access pose considerable periprocedural risk to cardiac structures. Therefore, we devised a novel method of pericardial access in which carbon dioxide (CO2) is insufflated through a right atrial puncture under fluoroscopic guidance, enabling clear visualization of the cardiac silhouette separating from the chest wall. We performed the procedure in 8 Landrace pigs, after which transthoracic percutaneous pericardial access was obtained by conventional means. All of the animals remained hemodynamically stable during the procedure, and none showed evidence of epicardial or coronary injury. The protective layer of CO2 in the pericardial space anterior to the heart facilitated percutaneous access in our porcine model, and the absence of complications supports the potential safety of this method.  相似文献   
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Using ex vivo human tooth, the authors demonstrated that dental pulp stromal cells that survive after placement of composite, mineral trioxide aggregate, and glass ionomer are weaker since they undergo synergistic cell death when exposed to 2-hydroxyethylmethacrylate. DPSCs extracted from teeth that were restored with the combination of composite or MTA or GI with N-acetyl cysteine were protectedfrom cell death. Therefore, application of NAC may protect the DPSCs from adverse effects after tooth restoration.  相似文献   
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Higher sympathetic activity predisposes to malignant ventricular arrhythmias in the context of myocardial infarction (MI). This is, in part, mediated by the electrical activity of the stellate ganglion (SG). The aim of this study is to examine the effects of ticagrelor pretreatment on the electrophysiological properties of SG neurons following MI in rabbits. MI was induced by isoproterenol (ISO) of 150 mg kg-1 d-1 (twice at an interval of 24 hours). Ticagrelor pretreatment was administered at low- (10 mg kg-1 d-1) or high-dose (20 mg kg-1 d-1). Protein and RNA expression were determined by immunohistochemical analysis and real-time PCR, respectively. The activity of sodium channel current (INa), delayed rectifier potassium current (IKDR), M-type potassium current (IKM) as well as action potentials (APs) from SG neurons were measured by whole-cell patch-clamp. Intracellular calcium concentrations were measured by confocal microscopy. Compared with the control group, the MI group exhibited a greater amplitude of INa, IKDR and IKM, significantly altered activation and inactivation characteristics of INa, no significant alterations in protein or mRNA expression of sodium and M-type potassium channels, along with higher AP amplitude and frequency and intracellular calcium concentrations. Most of these abnormalities were prevented by pretreatment with low- or high-dose ticagrelor. Our data suggest that ticagrelor exerts cardioprotective effects, potentially through modulating the activity of different ion channels in SG neurons.  相似文献   
10.
To evaluate the association between vascular risk factors and cognitive impairment among older African American (AA) adults in a primary care clinic. Participants included 96 AA adults aged 60 years or older who were evaluated for global and domain-specific cognition. Participants were interviewed using the Computerized Assessment of Memory and Cognitive Impairment (CAMCI). The relationship between CAMCI cognitive domain scores and vascular risk factors were examined using hierarchical regression models. Patients who smoked, those with higher SBP/DBP values had lower accuracy rates on CAMCI cognitive domains (attention, executive, memory).Those with higher BMI had better attention scores. Patients with higher HbA1C values had worse verbal memory. Patients with higher blood pressure were significantly faster in responding to tasks in the executive domain. Primary care providers working with older AA adults with these VRFs could implement cognitive screening earlier into their practice to reduce barriers of seeking treatment.  相似文献   
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