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The antihepatotoxic activity of elaterium (dried juice of the fruits of Ecballium elaterium, Cucurbitaceae) and cucurbitacin B (isolated from the juice) was studied against CCl4-induced hepatotoxicity. Pre- and posttreatment with elaterium and cucurbitacin B reduced CCl4-hepatotoxicity, as shown reduction in the anormally increased sGPT levels. Posttreatment caused a significant reduction in the degree of steatosis observed inthe control group, treated only with CCl4. In conclusion, elaterium and cucurbitacin B had preventive and curative effects against CCl4-induced hepatotoxicity.  相似文献   
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Bashir K  Cai CY  Moore TA  Whitaker JN  Hadley MN 《Neurosurgery》2000,47(3):637-42; discussion 642-3
OBJECTIVE: The goal of this study was to investigate the clinical and paraclinical features, treatment, and outcomes of patients with multiple sclerosis (MS) and coexisting spinal cord compression secondary to either cervical spondylosis or cervical disc disease. Patients with MS commonly experience neurological disabilities that present as myelopathy associated with bladder dysfunction. For some patients with MS, however, this neurological deterioration may result from coexisting spinal cord compression attributable to either spondylosis or a herniated disc. Overlapping symptoms of the two conditions do not allow clear clinical determination of the underlying cause of worsening. METHODS: Patients with MS who underwent cervical decompression surgery were selected. Medical records were retrospectively reviewed, to collect data on their pre- and postoperative clinical courses. RESULTS: Nine women and five men with definite MS were selected for cervical decompression surgery to treat neurological deterioration considered to be at least partially attributable to spinal cord compression. The most common symptoms were progressive myelopathy (n = 13), neck pain (n = 11), and cervical radiculopathy (n = 10). Bladder dysfunction was notably absent among these patients with MS with moderate disabilities. Surgical intervention was frequently delayed because the neurological deterioration was initially thought to be attributable to MS. The majority of patients experienced either improvement or stabilization of their preoperative symptoms in the immediate postoperative period; three subjects (21%) maintained this improvement after a mean follow-up period of 3.8 years. No MS relapses, permanent neurological worsening, or serious complications resulting from surgery or general anesthesia were noted. CONCLUSION: Carefully selected patients with MS and cervical spinal cord compression secondary to either spondylosis or disc disease may benefit from surgical decompression, with minimal associated morbidity. Clinical features (especially neck pain and cervical radiculopathy) and magnetic resonance imaging may assist clinicians in differentiating between the two conditions and may guide appropriate treatment without undue delay.  相似文献   
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Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1–20?mg/kg), on the early acute (4–24?h post-exposure) and late phase response (96?h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2?mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24?h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24?h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP.  相似文献   
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Conductive polymeric hydrogels (CPHs) exhibit remarkable properties such as high toughness, self-recoverability, electrical conductivity, transparency, freezing resistance, stimulus responsiveness, stretch ability, self-healing, and strain sensitivity. Due to their exceptional physicochemical and physio-mechanical properties, among the widely studied CPHs, polyaniline (PANI) has been the subject of immense interest due to its stability, tunable electrical conductivity, low cost, and good biocompatibility. The current state of research on PANI hydrogel is discussed in this short review, along with the properties, preparation methods, and common characterization techniques as well as their applications in a variety of fields such as sensor and actuator manufacturing, biomedicine, and soft electronics. Furthermore, the future development and applications of PANI hydrogels are also mentioned.

Conductive polymeric hydrogels (CPHs) exhibit remarkable properties for advance technological applications.  相似文献   
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ObjectiveTo describe the use of the Internet by primary care patients to seek health related information, understand how they are influenced by this information, and evaluate its impact on the doctor-patient relationship.DesignCross sectional study, through self-administered survey.SettingOne urban health center in Madrid.ParticipantsA total of 323 questionnaires were collected from patients between 14 and 75 years old who attended a physician's office for any reason, excluding illiterate patients and those with neurological or psychiatric problems preventing them from completing the survey.MeasurementsInternet usage, ability of the internet to clarify doubts regarding health issues, patient lifestyle changes, socio-demographic variables, and physician's receptivity to the use of internet by patients.Results61% (CI 95%: 56%-67%) of patients used the Internet as a source of health information: Internet queries were able to address health doubts in 92.4% of users, 53.5% reported that the Internet changed their thinking about their health in at least one instance, 30% made behavioral changes (of which 60.1% discussed these changes with their physician), 44.3% had more questions at the physician's office, and 80.8% believe that the doctor would be willing to talk about the information found on the internet.ConclusionsUsing the Internet to find information about health is very common, with positive influence on physician-patient relationship. This may be useful for achieving behavioral changes in patients and can be used as a tool in medical practice.  相似文献   
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