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81.
Open abdominal procedures are associated with high levels of postoperative surgical stress that can impede recovery of physiological functions. Trauma resulting from aggressive manipulation of organs, and especially the intestine, can increase postoperative complications and result in delay in normal recovery. In an attempt to minimize complications and overall duration of hospital stay, fast track strategies, called “early recovery after surgery” (ERAS) protocols, have been adopted. Laparoscopic surgery has recently been identified as a major component of rapid recovery. One of the key differences between the open and the laparoscopic approach is the use of pneumoperitoneum for organ exposure during laparoscopy. Prolonged increase in abdominal pressure in addition to patient positioning can have a profound effect on hemodynamic parameters such as central venous pressure (CVP), cardiac output and intracranial pressure. Modifications in fluid administration, the choice of anesthetic agent and the depth of neuromuscular blockade are indicated to accommodate to the conditions imposed by pneumoperitoneum. Postoperatively, laparoscopic surgery is usually associated with less aggressive analgesia management. Based on ERAS protocols, patients are encouraged to initiate early oral feeding and to resume physical activity as soon as possible after abdominal surgery. While laparoscopic abdominal surgery is associated with reduced needs for pain medication, there appear to be no significant differences in early enteral feeding and mobilization between laparoscopic procedures and open surgery. When all factors are taken into consideration, however, laparoscopic colorectal surgery is associated with significant reduction in the duration of the total hospital stay, and is therefore recommended whenever feasible.  相似文献   
82.
The aim was to evaluate the presence of Staphylococcus spp., Enterobacteriaceae and Pseudomonadaceae in the oral cavities of HIV-positive patients. Forty-five individuals diagnosed as HIV-positive by ELISA and Western-blot, and under anti-retroviral therapy for at least 1 year, were included in the study. The control group constituted 45 systemically healthy individuals matched to the HIV patients to gender, age and oral conditions. Oral rinses were collected and isolates were identified by API system. Counts of microorganisms from HIV and control groups were compared statistically by a Mann–Whitney test (α = 5%). The percentages of individuals positive for staphylococci were similar between the groups (p = 0.764), whereas for Gram-negative rods, a higher percentage was observed amongst HIV-positive (p = 0.001).There was no difference in Staphylococcus counts between HIV and control groups (p = 0.1008). Counts were lower in the oral cavities of patients with low viral load (p = 0.021), and no difference was observed in relation to CD4 counts (p = 0.929). Staphylococcus aureus was the most frequently isolated species in HIV group, and Staphylococcus epidermidis was the prevalent species in the control group. Significantly higher numbers of enteric bacteria and pseudomonas were detected in the oral cavities of the HIV group than in the control (p = 0.0001). Enterobacter cloacae was the most frequently isolated species in both groups. Counts of enteric bacteria and pseudomonas were significantly lower in patients with low CD4 counts (p = 0.011); however, there was no difference relating to viral load. It may be concluded that HIV group showed greater species diversity and a higher prevalence of Enterobacteriaceae/Pseudomonadaceae.  相似文献   
83.
1 Introduction  ItisknownbyallthatpurifiedsampleDNAisnecessarytocarryoutthe polymerasechainreactionbecauseofitshighsensitivity .IntissuesaffectedbyHodgkinsdisease ,theneoplasticelements ,H/R Scells (usuallylessthan 1% )amidstamajorpopulationoflymphocytes ,pla…  相似文献   
84.
Background The pathogenesis of progressive macular hypomelanosis (PMH) is unknown. Recently, Westerhof et al. (Arch Dermatol 2004; 140: 210–214) hypothesized that Propionibacterium acnes produces a depigmenting factor that interferes with melanogenesis in the skin, resulting in hypopigmented spots. The purpose of the study is to gain an insight into the pathogenesis of PMH. Materials and methods We took a biopsy of 2‐mm diameter from normal and lesional skin in eight PMH patients. Using electron microscopy, we compared melanization of melanosomes, melanosome transfer and amount of epidermal melanin in normal and lesional skin. Result Compared to non‐lesional skin, we observed a decrease of epidermal melanin and less melanized melanosomes in lesional skin of all patients. When comparing normal and lesional skin of patients with skin type V and VI, we observed a difference in melanosome size and maturation and a switch of transferred melanosomes from single stage IV transferred melanosomes to aggregated stage I, II and III transferred melanosomes, as seen in healthy skin of skin type I to IV. Conclusion Hypopigmentation in PMH seems to be the result of an altered melanogenesis based on a decrease in melanin formation and a change in the distribution of melanosomes. In lesional skin of PMH patients with skin type V and VI less melanized, aggregated melanosomes in stead of single, mature melanosomes are transferred from melanocytes to keratinocytes. This results in a decrease of epidermal melanin. Further investigations are needed to determine the precise role of Propionibacterium acnes in this alteration of melanogenesis.  相似文献   
85.

Background

Unplanned hospital readmissions are indicators of the quality and performance of a health care system, but data on early readmission after primary total knee arthroplasty (TKA) in the Asian population are limited. The purpose of this study was to determine the causes, risk factors, and rate of unplanned readmission after primary TKA at a single institution in Korea.

Methods

We analyzed all primary TKAs from 2004 to 2013 using the data from our institutional electronic database. A total of 4596 TKAs were performed on 3049 patients. All unplanned readmissions within 30 and 90 days of discharge were identified, categorized into arthroplasty-related, medical, and other orthopedic causes.

Results

The overall unplanned readmission rate was 1.9% (n = 59) within 30 days and 3.3% (n = 101) within 90 days, and both the 30 and 90 day readmission rates remained stable over the entire study period. The majority of readmissions involved arthroplasty-related causes; the most common cause being wound problems, accounting for 22% (13/59) within 30 days and 24% (24/101) within 90 days. Age (P = 0.029) and hypertension (P = 0.021) were identified as risk factors for unplanned readmissions after TKA.

Conclusion

This study demonstrates that unplanned readmissions after TKA are not infrequent in Korean patients and has identified wound complication as the most frequent cause of unplanned readmissions. Optimized care systems should be established to minimize unplanned readmissions, particularly for patients with high risk factors.  相似文献   
86.

Background

Neural circuits can spontaneously generate complex spatiotemporal firing patterns during development. This spontaneous activity is thought to help guide development of the nervous system. In this study, we had two aims. First, to characterise the changes in spontaneous activity in cultures of developing networks of either hippocampal or cortical neurons dissociated from mouse. Second, to assess whether there are any functional differences in the patterns of activity in hippocampal and cortical networks.

Results

We used multielectrode arrays to record the development of spontaneous activity in cultured networks of either hippocampal or cortical neurons every 2 or 3 days for the first month after plating. Within a few days of culturing, networks exhibited spontaneous activity. This activity strengthened and then stabilised typically around 21 days in vitro. We quantified the activity patterns in hippocampal and cortical networks using 11 features. Three out of 11 features showed striking differences in activity between hippocampal and cortical networks: (1) interburst intervals are less variable in spike trains from hippocampal cultures; (2) hippocampal networks have higher correlations and (3) hippocampal networks generate more robust theta-bursting patterns. Machine-learning techniques confirmed that these differences in patterning are sufficient to classify recordings reliably at any given age as either hippocampal or cortical networks.

Conclusions

Although cultured networks of hippocampal and cortical networks both generate spontaneous activity that changes over time, at any given time we can reliably detect differences in the activity patterns. We anticipate that this quantitative framework could have applications in many areas, including neurotoxicity testing and for characterising the phenotype of different mutant mice. All code and data relating to this report are freely available for others to use.  相似文献   
87.
BACKGROUND: Hempseed is a novel functional food that contains several health-promoting polyunsaturated fatty acids (PUFAs). PUFAs, such as those found in flaxseed and fish, have been shown to protect the heart against arrhythmias following ischemia/reperfusion. OBJECTIVE: TO INVESTIGATE THE POTENTIAL OF DIETARY HEMPSEED AS A CARDIOPROTECTIVE AGENT AGAINST GLOBAL ISCHEMIA AND SUBSEQUENT REPERFUSION BY ASSESSING SEVERAL MEASUREMENTS OF CARDIAC PERFORMANCE: QT interval duration, left ventricular pressure, arrhythmia incidence and arrhythmia duration. METHODS: MALE NEW ZEALAND WHITE RABBITS WERE FED ONE OF SIX DIETS: a control diet; or one supplemented with 10% hempseed, 10% delipidated hempseed, 0.5% cholesterol, 0.5% cholesterol plus 10% hempseed or 5% coconut oil. After eight weeks on their respective diets, the hearts were excised and subjected to 30 min of global ischemia and 45 min of reperfusion. Electrocardiogram traces were recorded throughout the experiment and were subsequently analyzed for QT interval duration, left ventricular pressure, arrhythmia incidence and arrhythmia duration. Plasma and cardiac tissue were analyzed for fatty acid content and composition. RESULTS: Cholesterol-fed animals exhibited significantly higher PUFA levels in their plasma, but this did not directly translate into higher PUFA levels in their cardiac fractions. There were no significant differences among the groups in the incidence or duration of ischemia-derived arrhythmias. During reperfusion, there was a significant decrease in the incidence of fibrillation in the hearts obtained from cholesterol-fed and hempseed- plus cholesterol-fed rabbits compared with the hearts from delipidated hempseed-fed rabbits. CONCLUSIONS: Dietary hempseed induced limited beneficial effects on cardiac function during ischemia/reperfusion challenge. The present study does not support the use of dietary hempseed to protect the heart during ischemic insult in this experimental model.  相似文献   
88.
Hematopoietic depression and subsequent susceptibility to potentially lethal opportunistic infections are well-documented phenomena following radiotherapy. Methods to therapeutically mitigate radiation-induced myelosuppression could offer great clinical value. In vivo studies in our laboratory have demonstrated that interleukin-6 (IL-6) stimulates pluripotent hematopoietic stem cell (CFU-s), granulocyte-macrophage progenitor cell (GM-CFC), and erythroid progenitor cell (CFU-e) proliferation in normal mice. Based on these results, the ability of IL- 6 to stimulate hematopoietic regeneration following radiation-induced hematopoietic injury was also evaluated. C3H/HeN female mice were exposed to 6.5 Gy 60Co radiation and subcutaneously administered either saline or IL-6 (1,000 micrograms/kg) on days 1 through 3 or 1 through 6 postexposure. On days 7, 10, 14, 17, and 22, femoral and splenic CFU-s, GM-CFC, and CFU-e contents and peripheral blood white cell, red cell, and platelet counts were determined. Compared with saline treatment, both 3-day and 6-day IL-6 treatments accelerated hematopoietic recovery; 6-day treatment produced the greater effects. For example, compared with normal control values (N), femoral and splenic CFU-s numbers in IL-6-treated mice 17 days postirradiation were 27% N and 136% N versus 2% N and 10% N in saline-treated mice. At the same time, bone marrow and splenic GM-CFC values were 58% N and 473% N versus 6% N and 196% N in saline-treated mice; bone marrow and splenic CFU-e numbers were 91% N and 250% N versus 31% N and 130% N in saline-treated mice; and peripheral blood white cell, red cell, and platelet values were 210% N, 60% N, and 24% N versus 18% N, 39% N, and 7% N in saline- treated mice. These studies demonstrate that therapeutically administered IL-6 can effectively accelerate multilineage hematopoietic recovery following radiation-induced hematopoietic injury.  相似文献   
89.
Treating patients with systemic lupus erythematosus (SLE) with steroids and immunosuppressive drugs may interfere in the presence of potentially opportunistic microorganisms in the oral cavity. The aim of this study was to evaluate the presence of Candida spp., Staphylococcus spp., Enterobacteria and Pseudomonas spp. in the oral cavity of SLE patients, compared with healthy controls. A group of 40 patients who had received therapy for at least 60 days was selected (19-53 years). For the control group, 40 healthy individuals matched for age, gender and use of partial prosthesis were selected. Oral rinse samples were collected and plated on specific culture media. After incubation, the number of colony forming units (CFU) was obtained and the isolates were identified at species level. Microbial counts were compared between SLE and control by analysis of variance (ANOVA) and Mann-Whitney (p?相似文献   
90.
Objective:To evaluate functional outcome and complications of open reduction and internal fixation with proximal humeral internal locking system (PHILOS) plate for proximal humerus fractures.Methods:We reviewed 51 patients who underwent open reduction and internal fixation with PHILOS plate between the years 2007 to 2012.There were 35 men and 16 women with a mean age of 38 years (range 24-68).There were 41 patients in the age group of <60 years and 10 patients in the age group of >60 years.According to Neer classification system,8,15 and 23 patients had 2-part,3-part,and 4-part fractures,respectively and 5 patients had 4-part fracture dislocation.All surgeries were carried out at our tertiary care trauma centre.Functional evaluation of the shoulder at final follow-up was done using Constant-Murley score.Results:The mean follow-up period was 30 months (range 12-44 months).Two patients were lost to followup.Of the remaining 49 patients,all fractures were united clinically and radiologically.The mean time for radiological union was 12 weeks (range 8-20 weeks).At the final follow-up the mean Constant-Murley score was 79 (range 50-100).The results were excellent in 25 patients,good in 13 patients,fair in 6 patients and poor in 5 patients.During the follow-up,four cases of varus malunion,one case of subacromial impingement,one case of deep infection,one case of intraarticular screw penetration and one case of failure of fixation were noted.No cases of avascular necrosis,hardware failure,locking screw loosening or nonunion were noted.Conclusion:PHILOS provides stable fixation in proximal humerus fractures.To prevent potential complications like avascular necrosis,meticulous surgical dissection to preserve vascularity of humeral head is necessary.  相似文献   
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