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The purpose of the study was to compare skin blood flow by laser Doppler flowmetry (LDF) and the 133-Xenon washout technique in UVB-inflamed human skin. Six healthy subjects participated in the study. Forearm skin blood flow was measured prior to irradiation and then 8, 24, 48 and 72 h after the exposure to twice the minimal erythema dose of UVB. Baseline blood flow as measured by the 133-Xenon washout method was 5.2 (range 3.0 to 10.4) ml/100g/min and LDF flux was 3.1 (range 2.7 to 5.7) arbitrary units. Following irradiation, maximum blood flow increase as evaluated by the 133-Xenon washout was 10.8 (95% confidence interval 3.7 to 11.3) times baseline blood flow, corresponding to an absolute blood flow of 47.5 (range 33.8 to 56.3) ml/100g/min. Maximum increase after induction of inflammation as assessed by LDF was 34.6 (95% confidence interval 24.6 to 56.5) times baseline flux. The two methods showed comparable time courses in all subjects. A significant correlation between the two methods was found, Spearman's rho = 0.54, p = 0.006. The relative LDF blood flow increase was 4.2-fold (95% confidence interval 2.7 to 5.0) greater than the increase measured by the 133-Xenon washout method. These results are at variance with previous comparative studies of the two methods. Some explanations are discussed.  相似文献   
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Background: Neuropathic pain in spinal cord injury is a common challenging therapeutic condition. The current study examines the analgesic effect of the sodium channel blocker lidocaine on neuropathic pain in patients with spinal cord injury and the predictive role of concomitant evoked pain on pain relief with lidocaine.

Methods: Twenty-four spinal cord injury patients with neuropathic pain at or below the level of injury were randomized and completed a double-blind crossover trial of 5 mg/kg lidocaine and placebo infused over 30 min. Twelve patients reported evoked pain, and 12 patients had no evoked pain. Spontaneous and evoked pains were assessed using a visual analog scale and quantitative sensory testing.

Results: Lidocaine significantly reduced spontaneous pain in all patients (P < 0.01) and in each of the two groups with (P < 0.01) and without (P = 0.048) evoked pain, with no difference in number of responders (pain reduction >= 33%) between the patients with (n = 6) and without (n = 5) evoked pain. Lidocaine significantly relieved both at-level and below-level neuropathic pain and decreased brush-evoked dysesthesia but not cold allodynia, pinprick hyperalgesia, or pain evoked by repetitive pinprick.  相似文献   

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de Vries Reilingh  TS  van Geldere  D  Langenhorst  BLAM  de Jong  D  van der Wilt  GJ  van Goor  H  Bleichrodt  RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique.  相似文献   
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BACKGROUND: Acute respiratory infections (ARIs) are an important cause of infant morbidity in both developing and developed countries, and they are the leading cause of death in poorer parts of the world. Respiratory viruses appear to be the most frequent microbiological pathogens, especially respiratory syncytial virus. It has been suggested that factors such as being male, overcrowding, poor access to medical care, low level of maternal education, and passive smoking are associated with contracting ARIs. DESIGN: A fixed birth cohort of 571 children was followed from birth to 1 year of age. The children were monitored for symptoms of ARIs during regular home visits. SETTING: An urban low-income setting in Soweto, a township outside Johannesburg with an estimated 1.2 million inhabitants, including an estimated 45,000 children under 2 years of age. SUBJECTS: A total of 571 children were observed for 118,650 days. OUTCOME MEASURES: The incidence rate of ARIs. The determinants birth weight, breastfeeding, gender, crowding, passive smoking, indoor pollution, and sanitary facilities were analysed. RESULTS: A total of 489 episodes of coughing or coughing and nasal discharge combined were recorded. Only the father's level of education and the number of people living in the household remained significant in the multivariate analyses. The incidence of severe ARIs was reduced among breastfed infants. CONCLUSIONS: Our study supports previous observations suggesting that crowding and communal living conditions are important determinants of ARIs. Breastfeeding seemed protective against severe ARI. The lack of association with well-described risk factors such as low level of maternal education, gender and passive smoking could be due to lack of statistical power in this rather uniform population.  相似文献   
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OBJECTIVE: To test whether healthcare workers' knowledge of and compliance with the basic principle of the Universal Precautions policy (i.e., that all patients should be treated equally regarding contact with body fluids) influenced the rate of contact with patient blood. DESIGN: Survey based on anonymous questionnaires. SETTING: A 380-bed secondary and tertiary care hospital receiving emergency and elective patients. PARTICIPANTS: All employees having any contact with patients. Nine hundred one of 1,308 (69%) of the questionnaires were returned. RESULTS: Twelve percent of the respondents (95% confidence interval [CI95] = 10.0%-14.4%) had experienced any contact with patient blood in the week preceding their answer. Physicians had the highest rate of contact with blood followed by nurses. In the five groups--physicians, nurses, laboratory technicians and phlebotomists, nursing aides, and student nurses--contact with blood was less frequent in the subgroup that did know and comply with the basic principle of the Universal Precautions policy, compared with the subgroup that did not. When adding the results for the 5 groups, contact with blood was experienced by 91 of 571 (15.9%, CI95 = 13%-19%) of the personnel who did not know and comply with Universal Precautions. The personnel who did know and comply with Universal Precautions had a significantly lower (9 of 111 [8.1%], p < .05, CI95 = 3.8%-15%) rate of contact with blood. CONCLUSIONS: The healthcare workers who knew and complied with Universal Precautions had a significant lower rate of contact with patient blood than those who did not.  相似文献   
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A case of a muscular hamartoma of the breast in a 47-year-old woman is presented. Tumors containing smooth muscle are rare in the breast. Radiologically it appears as a circumscribed tumor with homogeneous or varying density. Histologically these lesions are composed of ducts, lobules, stroma prominently adipose, and smooth muscle.  相似文献   
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During the last year we developed a disposable anal plug electrode for pelvic floor/external anal sphincter electromyography. The electrode consists of 2 disposable silver chloride surface electrodes mounted on a trochlear-shaped sponge. Testing of the new electrode with simultaneous registration of external anal sphincter electromyography using a coaxial needle electrode showed synchronous electromyographic patterns. In clinical urodynamic studies, including 48 cystometry studies with anal sphincter electromyography and 48 pressure-flow electromyographic studies, the electrode provided technically good and reliable electromyograms. The electrode design secures good contact to the recording surface and a safe fixation of the electrode during recording. The compressibility of the electrode might circumvent the problem of possible detrusor reflex inhibition induced by conventional hard anal plug electrodes. We recommend this technique for anal sphincter electromyography, since it is simple, reliable and without discomfort, and it does not require sterilization of the electrode.  相似文献   
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