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1.
SH Lee† CP Choi‡ HC Eun† OS Kwon† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):860-863
BACKGROUND: On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. OBJECTIVE: To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. METHODS: Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. RESULTS: The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. CONCLUSIONS: Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required. 相似文献
2.
Diane M. Burnard Quentin J. Pittman Brian A. MacVicar 《Journal of neuroendocrinology》1991,3(4):433-439
Intracellular recordings were obtained from pituicytes in the neural lobe of the isolated rat pituitary. Like other glia, pituicytes lacked action potentials in response to depolarizing current injection, but they tended to have more positive resting membrane potentials and higher input resistances than astrocytes in other preparations. Dye-coupling typical of astrocytes was also demonstrated amongst pituicytes, and their morphologies were similar to those of pituicytes stained for glial fibrillary acidic protein. Action potentials, anode-break spikes or barium spikes were not observed in pituicytes, even under conditions that maximized the elicitation of Ca2+-dependent responses. This suggests that pituicytes either have no or a very low density of Ca2+ channels or Ca2+ currents that are too small to generate action potentials. Dynorphin A (1–13), a kappa-opioid agonist, produced long-lasting increases in pituicyte input resistance with no significant changes in resting membrane potential. Dynorphin's action was concentration-dependent and was blocked by the opioid antagonist naloxone. This is consistent with previous reports demonstrating kappa-opioid receptors on pituicytes in the neurohypophysis. The β-adrenergic agonist isoproterenol (100 μM) reversed the increases in pituicyte input resistance produced by opioid application, with no significant changes in resting membrane potential. The fact that pituicytes responded to neurotransmitters suggests a functional link between pituicytes and neurosecretory nerve fibres. 相似文献
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Elevated serum sodium and potassium levels were recently observed when sampled through a heparin-bonded umbilical catheter and measured with certain ion-selective electrodes. The cationic surfactant, benzalkonium chloride (BZC), is known to falsely elevate those cations in serum. Inasmuch as most heparin-bonded umbilical catheters use BZC during the bonding process, an in vitro study was performed to estimate the quantity of BZC released and the duration of sodium and potassium elevations during pooled sera infusion. Three heparin-bonded umbilical catheters and 3 silastic umbilical catheters were first flushed with 0.3 mL of normal saline and then perfused with pooled sera (sodium, 142 mEq/L; potassium, 4.6 mEq/L) at 2.5 microL/h. Effluent samples were collected from 0 to 8 hours and analyzed by ion-selective electrodes. Elevated serum sodium concentrations from 160 to greater than or equal to 250 mEq/L and potassium concentrations from 6.0 to greater than or equal to 9.6 mEq/L were observed. The BZC concentration in the catheter effluent was measured by mass spectrometry, with peak values of 10 micrograms/mL detected by this method. When varying concentrations of BZC (1 to 100 micrograms/mL) were added directly to pooled serum, a dose-dependent increase in serum sodium was observed. These data demonstrate that BZC released from heparin-bonded umbilical catheters elevates serum electrolyte values measured with some ion-selective electrodes. The observed increase in sodium and potassium concentrations may lead to clinical errors in management. Benzalkonium chloride is associated with myriad of linical symptomatology. Whether this amount of BZC is toxic in the small premature neonate is presently unknown. 相似文献
6.
Neuropeptide Y action in the rat hippocampal slice: site and mechanism of presynaptic inhibition 总被引:10,自引:0,他引:10
Neuropeptide Y (NPY), the most abundant peptide in mammalian CNS, has been shown to inhibit excitatory neurotransmission presynaptically at the stratum radiatum-CA1 synapse in the in vitro rat hippocampal slice. We examined the site and mechanism of this inhibition in a series of in vitro intra- and extracellular recordings in areas CA1 and CA3, the source of much of the excitatory synaptic input to the CA1 neurons. NPY's inhibitory action at the stratum radiatum-CA1 synapse was unaffected by high concentrations of the antagonists bicuculline, theophylline, or atropine, suggesting that it does not act by stimulating the release of the known presynaptic inhibitory transmitters GABA, adenosine, or ACh, respectively. Bath application of 10(-6) NPY, a concentration that strongly inhibited the stratum radiatum-CA1 synapse had no effect on CA3 neuron resting potential, input resistance or action potential amplitude, threshold, or duration. NPY also does not alter the amplitude or duration of the prolonged CA3 action potentials evoked in the presence of TTX, tetraethyl-ammonium, and elevated external Ca2+ or those evoked in the presence of TTX and Ba2+ ions. NPY therefore does not alter the passive or active properties of the somata of the presynaptic CA3 neurons. Neither the afferent fiber volley of the Schaffer collaterals in stratum radiatum of area CA1 nor the excitability of the CA3 terminals in CA1 was affected by NPY application. However, application of the transient K+ current blocker, 4-aminopyridine (4-AP) at concentrations of 10 and 50 microM, completely abolished the action of 10(-6) M NPY on the stratum radiatum-CA1 excitatory synaptic potentials. This action of 4-AP could be reversed by reducing extracellular Ca2+ concentrations from a control level of 1.5 to 0.7 mM (in 10 microM 4-AP) and to 0.5 mM (in 50 microM 4-AP). The evidence suggests that NPY inhibits excitatory synaptic transmission at the Schaffer collateral-CA1 synapse by acting directly at the terminal to reduce a Ca2+ influx. 相似文献
7.
Previous studies reviewing the morbidity and mortality of infant inguinal hernia surgery have all been done in university hospital settings. From our community-based tertiary hospital, 100 consecutive cases on infants less than six months of age, undergoing inguinal hernia repair, were reviewed. No infants were excluded. Sixty-eight were full term and 32 were premature. A number of different variables were analyzed and none appeared to affect outcome. Infants were followed for three to five years. There were no true complications in any infant in this series, although six infants developed wound erythema that resolved spontaneously. Parents were given a questionnaire to subjectively evaluate the infant before and after surgery with 78% showing improvement. 相似文献
8.
Joyce Pittman 《Journal of wound, ostomy, and continence nursing》2007,34(4):412-5; quiz 416-7
The population is aging, and advanced age is commonly identified as a risk factor for delayed wound healing. Therefore, it is important for WOC nurses to be knowledgeable about how aging affects the wound healing and repair process, and strategies they can use to promote healing in the elderly population. Impaired wound healing in the aged is due partly to comorbidities common among the elderly, but evidence also suggests that inherent differences in cellular structure and function may impair tissue repair and regeneration as well. This article will address the effect of aging on wound healing, with a particular focus on processes of cellular senescence and related factors hypothesized to result in slowed or impaired wound healing in the elderly. 相似文献
9.
Jeffrey H. Ware Angela J. Dibenedetto Randall N. Pittman 《Brain research bulletin》1995,37(3):275-281
The distribution of tissue plasminogen activator (tPA) messenger RNA in rat brain was studied using in situ hybridization with 35S UTP-labeled RNA probes derived from a fulllength tPA cDNA. Sense strand controls produced low, even backgrounds, with small elevations in the hippocampus. Full-length antisense probes produced strong signals over cerebral ventricular ependyma (including ependyma of the subcommissural organ), meninges, blood vessels, and Purkinje cell layer of the cerebellum, as well as strong signals over scattered cells throughout the brain. Some of these scattered labeled cells were large with lightly stained nuclei, while others were small with darkly stained nuclei. The large labeled cells, which were probably neurons, constituted 8% and 8% of cells in the brain stem and neocortex, respectively, and 100% of Purkinje cells. The small cells, which were present in all areas of the brain, constituted 3–11 % of cells in individual brain areas. 相似文献
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