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排序方式: 共有4012条查询结果,搜索用时 31 毫秒
921.
922.
923.
The impact of ischemia time during open nephron sparing surgery on solitary kidneys: a multi-institutional study 总被引:4,自引:0,他引:4
Thompson RH Frank I Lohse CM Saad IR Fergany A Zincke H Leibovich BC Blute ML Novick AC 《The Journal of urology》2007,177(2):471-476
PURPOSE: The safe duration of ischemia during nephron sparing surgery remains controversial. We performed a multi-institutional study to evaluate the renal effects of vascular clamping in patients with solitary kidneys. MATERIALS AND METHODS: Using the Cleveland Clinic and Mayo Clinic databases, we identified 537 patients with solitary kidneys who underwent open nephron sparing surgery. Renal complications were compared among patients who did not require vascular clamping (85), and those who had warm ischemia (174) and cold ischemia (278). RESULTS: Median patient age (63, 65, 64 years) and preoperative creatinine (1.4, 1.3, 1.4 mg/dl) were similar among patients with no ischemia, warm ischemia and cold ischemia, respectively. Median tumor size was smaller in patients with no ischemia (2.5 cm), compared to patients with warm (3.5 cm) and cold (4.0 cm) ischemia (p <0.001). Warm and cold ischemia was associated with a significantly increased risk of urine leak (p = 0.006), acute (p <0.001) and chronic (p = 0.027) renal failure, and temporary dialysis (p = 0.028) compared to patients with no ischemia. Warm ischemia longer than 20 minutes and cold ischemia longer than 35 minutes were associated with a higher incidence of acute renal failure (p = 0.002 and p = 0.003, respectively). Additionally, warm ischemia more than 20 minutes was associated with an increased risk of chronic renal insufficiency (41% vs 19%, p = 0.008), increase in creatinine greater than 0.5 (42% vs 15%, p <0.001) and permanent dialysis (10% vs 4%, p = 0.145). CONCLUSIONS: Vascular clamping during open nephron sparing surgery is associated with a higher incidence of renal complications. Attempts to limit warm ischemia to 20 minutes and cold ischemia to 35 minutes should be used when vascular clamping is necessary. 相似文献
924.
Yurekli M Esrefoglu M Ilker Doğru M Doğru A Gul M Whidden M 《Environmental toxicology》2009,24(3):279-286
Adrenomedullin (AdM) is synthesized and secreted by a number of cells and tissue. AdM is a potent vasodilator but it is also considered a neuromodulator, an angiogenic factor, and a hormone regulator. AdM possess antiapoptotic, antioxidant, and antimicrobial properties. Heavy metals such as cadmium and lead are found widely in the environment and they have important biological functions. Lead (Pb) and cadmium (Cd) can accumulate in the lungs, liver, bone, and kidneys and cause serious organ damage. In the present study, we investigated the effect of AdM, Pb + AdM, and Cd + AdM treatments on superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities as well as the level of malondialdehyde (MDA) in the kidney. Heavy metal accumulation was determined in kidney with and without AdM infusion and kidney damage was evaluated by light and electron microscopy. Increased heavy metal accumulation was observed in the heavy metal and AdM treated groups. SOD, CAT, GSH-Px activities, and MDA levels were significantly different in the treatment groups when compared with the control group. Tubular degeneration, necrosis, cell swelling, mononuclear cell infiltration, and degenerated organelles were observed in the kidney following treatment. Therefore, AdM infusion has no beneficial and/or compensatory role in cadmium and lead toxicity in the kidney. We conclude that heavy metal accumulation in the kidney in conjunction with AdM infusion is cytotoxic despite the known beneficial effects of adrenomedullin. 相似文献
925.
Klauenberg S Maier C Assion HJ Hoffmann A Krumova EK Magerl W Scherens A Treede RD Juckel G 《Pain》2008,140(2):332-343
Although patients with a depressive disorder report often of pain, their sensitivity to experimental pain is controversial, probably due to differences in sensory testing methods and to the lack of normal values. Therefore, we used a standardized and validated comprehensive sensory testing paradigm to assess the peripheral and central nervous system performance in depressive patients compared to healthy controls and chronic pain patients with fibromyalgia syndrome (FMS), in which depression is a common comorbidity. Twenty-five depressive psychiatric inpatients (pain-free: n=20), 35 FMS outpatients and 25 healthy controls underwent quantitative sensory testing (QST), including thermal and mechanical detection and pain thresholds, pain sensitivity and responsiveness to repetitive noxious mechanical stimuli (wind-up). In depressive disorder (to a lesser extent also in FMS), significantly decreased cold pain thresholds and an increased wind-up were found, although the mechanical pain thresholds and pain sensitivity were comparable to those of the healthy controls. All the detection thresholds were within the normal range in all the groups. In depressive disorder, there were no significant side differences in the detection and pain thresholds. The results contradict the former assumption of a general insensitivity to experimental pain in depressive disorder. In the mostly pain-free patients signs of an enhanced central hyperexcitability are even more pronounced than usually found in chronic pain patients (e.g. FMS), indicating common mechanisms in depressive disorder and chronic pain in accordance with the assumption of non-pain associated mechanisms in depressive disorder for central hyperexcitability, e.g. by inhibited serotonergic function. Furthermore, this trial demonstrates the feasibility of QST in depressive patients. 相似文献
926.
测定苍耳子中重金属含量,并比较提取前后重金属含量变化。用乙醇提取苍耳子油,将提取物和原药材消化后,用火焰原子吸收分光光度法测定中药材提取前后重金属Cu、Pb、Cd、Mn的含量。结果表明苍耳子原药材中含有有害重金属Cu、Pb、Cd等,但提取后苍耳子油中重金属含量都有所降低,其中Cu含量下降最明显。提取后得到的苍耳子油在临床应用和作为食用油均比较安全。 相似文献
927.
Chemical Contamination of Green Turtle (Chelonia mydas) Eggs in Peninsular Malaysia: Implications for Conservation and Public Health
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Jason P. van de Merwe Mary Hodge Henry A. Olszowy Joan M. Whittier Kamarruddin Ibrahim Shing Y. Lee 《Environmental health perspectives》2009,117(9):1397-1401
Background
Persistent organic pollutants (POPs)—such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)—and heavy metals have been reported in sea turtles at various stages of their life cycle. These chemicals can disrupt development and function of wildlife. Furthermore, in areas such as Peninsular Malaysia, where the human consumption of sea turtle eggs is prevalent, egg contamination may also have public health implications.Objective
In the present study we investigated conservation and human health risks associated with the chemical contamination of green turtle (Chelonia mydas) eggs in Peninsular Malaysia.Methods
Fifty-five C. mydas eggs were collected from markets in Peninsular Malaysia and analyzed for POPs and heavy metals. We conducted screening risk assessments (SRAs) and calculated the percent of acceptable daily intake (ADI) for POPs and metals to assess conservation and human health risks associated with egg contamination.Results
C. mydas eggs were available in 9 of the 33 markets visited. These eggs came from seven nesting areas from as far away as Borneo Malaysia. SRAs indicated a significant risk to embryonic development associated with the observed arsenic concentrations. Furthermore, the concentrations of coplanar PCBs represented 3 300 times the ADI values set by the World Health Organization.Conclusions
The concentrations of POPs and heavy metals reported in C. mydas eggs from markets in Peninsular Malaysia pose considerable risks to sea turtle conservation and human health. 相似文献928.
Smita Pattanaik Punit Dhamija Samir Malhotra Navneet Sharma & Promila Pandhi 《British journal of clinical pharmacology》2009,67(3):363-369
AIMSDrug related events (DREs) contribute significantly to hospital admissions. These are largely preventable events and require optimum use of the therapeutic agents. The study was conducted to analyze the cost of treatment of DREs.RESULTSOut of 1833 admissions, 92(5.01%) were due to DREs. Maximum cases were due to non compliance (66%) followed by ADR (28%) and drug overdose(6%). The common DREs leading to ED visits were cerebrovascular accident(19.44%), followed by accelerated hypertension(18.36%) and diabetic ketoacidosis(14.04%). Total cost of management of all the 92 DREs in our hospital was calculated to be INR17,37,339(€30,215). The direct cost was INR1,72,961(€3008) and the approximate indirect cost was INR15,64, 378(€27, 206). The projected cost of management of all the 92 DREs was estimated to be INR63,63,872(€1,01, 676) in a private sector hospital.CONCLUSIONThe study shows that ADEs leading to emergency department visits and hospitalizations constitute a significant economic burden. Training of the patients and the prescribers may lessen the economic burden on the patient as well as the health care system. 相似文献
929.
BACKGROUND: Recruitment and retention of dentists in the public sector and rural areas in Victoria has become increasingly difficult in recent years. There are little available data on the factors that influence the sector and location of practice of new dental graduates. The objective of this study was to investigate the factors considered by new graduates in determining the location and sector of employment after graduation, and influencing any early changes in career path. METHODS: Questionnaires were sent to dentists who Mgraduated from The Univrersity of Melbourne from graduated from The University of Melbourne from 2000-2003 who were currently practising in Victoria. There were 154 subjects to whom questionnaires were sent and 109 useable questionnaires were returned, a response rate of 74 per cent. RESULTS: Upon graduation, 53 per cent of the new graduates chose to work in the private sector only, compared to 15 per cent in public sector only and 33 per cent in both. At present, 71 per cent work in the private sector only, 17 per cent in the public sector only and 12 per cent in both. The most important factors for choosing to work in the private sector were receiving broad range of clinical experience, opportunities to familiarize with practice management and providing a continuity of care. The principal factors for practising in the public sector were clinical mentoring and advice, consolidating clinical skills and work environment. Initially, 48 per cent of the sample chose to work in metropolitan areas only, 39 per cent in rural areas only and 13 per cent in both. Factors that influenced the decision to work in rural areas were the broad range of clinical experience and remuneration, while the main factors for choosing to work in metropolitan areas were lifestyle and proximity to family and friends. CONCLUSIONS: This study found that a large proportion of new dental graduates initially chose to work in the public sector and rural areas on graduation primarily as a means of consolidating their clinical skills. However, retention of dentists in both these areas appears to be a problem, with less than 10 per cent of 2000-2001 graduates still than 10 per cent of 2000-2001 graduates still working in the public sector and only 20 per cent of 2000-2001 graduates still working in rural areas. 相似文献
930.
Yasuhisa Oida Junya Hamanaka Kana Hyakkoku Masamitsu Shimazawa Takashi Kudo Kazunori Imaizumi Tadashi Yasuda Hideaki Hara 《Neuroscience letters》2010
We previously reported the effect of a selective inducer of BiP (a BiP inducer X; BIX) after permanent middle cerebral artery occlusion (MCAO) in mice. However, in acute stroke, almost all drugs have been used clinically after the onset of events. We evaluated the effect of post-treatment of BIX after permanent MCAO in mice, and examined its neuroprotective properties in in vivo mechanism. BIX (intracerebroventricular injection at 20 μg) administered either at 5 min or 3 h after occlusion reduced both infarct volume and brain swelling, but at 6 h after occlusion there was no reduction. BIX protected against the decrease in a dose-dependent manner. Furthermore, BIX reduced the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive cells induced by the ischemia in ischemic penumbra. These findings indicate that post-treatment with BIX after ischemia has neuroprotective effects against acute ischemic neuronal damage in mice even when given up to 3 h after MCAO. BIX may therefore be a potential drug for stroke. 相似文献