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11.
Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury.  相似文献   
12.
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction.  相似文献   
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Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation.  相似文献   
14.
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction.  相似文献   
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Efficacies of three alternate methods of postoperative analgesia were studied in 156 patients who had total knee arthroplasty (TKA). Forty-two of these patients received parenteral meperidine hydrochloride or morphine (Group 1), 58 patients received periodic epidural injections of morphine (Group 2), and 56 patients received continuous epidural infusions of bupivacaine hydrochloride and Duramorph (Group 3). The postoperative course of all patients was documented in terms of the incidence and severity of pain, range of joint motion, duration of hospitalization, and occurrence of complications. Although epidural analgesia increased the cost and duration of the operation, good-to-excellent pain relief was attained in 86% (Group 2) and 88% (Group 3) of cases with epidural analgesia compared with 61% of patients (Group 1) receiving conventional analgesia. Moreover, 67% of patients in Group 1 experienced frequent episodes of moderate-to-severe postoperative pain in contrast to 40% of patients in Group 2 and only 10% of patients in Group 3. As a result of diminished pain, greater joint motion was obtained within the first 72 hours in Groups 2 and 3. They also had shorter hospitalization (9.6 days versus 11.2 days for Group 1 and 10.8 days for Group 2). However, the use of epidural analgesia did not reduce the incidence of complications, including nausea. Continuous infusion of epidural bupivacaine and Duramorph provided good-to-excellent control of postoperative pain after TKA. However, better analgesics are needed to reduce the high incidence of side effects associated with various treatment methods.  相似文献   
20.
For almost three decades, many have regarded general hospital psychiatric units as the most appropriate setting for acute treatment of persons with serious mental illness who were once treated mostly in state hospitals. The extent to which this transfer has taken place and the differences between public and private general hospitals have been unclear. Using data from the 1988 National Mental Health Facilities Study and published data from the 1970s, the authors found that nearly half of all general hospitals providing psychiatric services treat persons with serious mental illness. Significant differences in case and payer mix were observed between public and private general hospitals, although these differences were smaller than in the 1970s. The findings suggest increased involvement by private general hospitals in treating patients reimbursed by public payers, but the findings also indicate that persons with serious mental illness and those using Medicaid are still more prevalent in public general hospitals than in private ones.  相似文献   
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