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991.
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Background

The potential effects of laparoscopic surgery on intra- and postoperative intraocular pressure (IOP) are not completely understood. Although prior studies have reported that pneumoperitoneum may increase IOP, it is not clear whether this increase is related to the effects of pneumoperitoneum or to the patient’s position, such as the Trendelenburg position. This study aimed to evaluate the potential fluctuations of IOP during colorectal laparoscopic surgery in two groups of patients: those with and those without Trendelenburg positioning.

Methods

For this prospective study 45- to 85-year-old patients undergoing laparoscopic colorectal surgery were enrolled after a thorough ophthalmologic assessment. The study protocol included measurement of IOP at eight different time points (before, during, and after surgery) using a contact tonometer in both eyes.

Results

The study enrolled 29 patients: 17 (58.6 %) with Trendelenburg position placement during surgery and 12 (41.4 %) without Trendelenburg positioning. The two groups did not differ in terms of gender, age, body mass index (BMI), American Society of Anesthesiology (ASA) class, or operative time. In all the patients, pneumoperitoneum induction led to a mild rise in IOP, averaging 4.1 mmHg. The patients with Trendelenburg positioning showed a greater increase than the patients without it (5.05 vs 4.23 mmHg at 45 min; p = 0.179), but IOP evaluation 48 h after surgery showed no substantial differences between the two groups. Among the 29 patients, 17 (58.6 %) showed an increase in IOP of 5 mmHg or more during surgery. A greater percentage of the patients who underwent Trendelenburg positioning showed an IOP increase of 5 mmHg or more (76.5 vs 33.3 %; p = 0.020). At the multivariate analysis, no potential predictors of increased IOP during surgery was identified.

Conclusions

Standard pneumoperitoneum (≤14 mmHg) led to mild and reversible IOP increases. A trend was observed toward a greater IOP increase in patients with Trendelenburg positioning. Thus, the patient’s position during surgery may represent a stronger risk factor for IOP increase than pneumoperitoneum-related intraabdominal pressure.  相似文献   
994.
Summary The transfer of cytokine genes into cancer cells, resulting in cytokine release directly at the site of tumor growth, has proven effective in inhibiting tumor growth in the absence of any toxic effect. Some cytokines induce tumor suppression even in T-cell-deficient mice, suggesting their potential therapeutic effect in poorly immunogenic tumors; other cytokines induce memory T cells that protect mice from subsequent tumor injection. The effects of cytokine genes transferred into tumor cells are summarized and implications discussed.  相似文献   
995.
The FIM instrument in the United States and Italy: a comparative study   总被引:1,自引:0,他引:1  
OBJECTIVE: To compare FIM instrument ratings between Italy and the United States. DESIGN: This study utilized 169,835 United States and 4,536 Italian FIM instrument records for stroke with the left side of the body affected, stroke with the right side of the body affected, and orthopedic conditions. RESULTS: Case-mix, patient age, and admission and discharge FIM instrument scores were similar. The delays between onset of disability and admission to rehabilitation and lengths of stay in rehabilitation were 2-4 times longer in Italy. In Italy, some 88-95% of the subjects were discharged to the community vs. 74-88% in the United States. Hierarchies of FIM instrument ratings across the motor and cognitive items were similar, but there were interesting differences. The hierarchical patterns showed that dressing, bathing, perineal hygiene, and tub or shower transfer were relatively more difficult in Italy compared with the Unites States, whereas walking was easier in Italy compared to the United States. CONCLUSION: The Italian health care payment system offers less incentive for early discharges from acute care and rehabilitation. In Italy, nursing homes are less accessible, whereas family support is more available. Apparently less intensive treatment is applied in Italy, where a minimum time per day for rehabilitation services is not mandatory for payment. Occupational therapy is not used in Italy and the focus is more on physical therapy.  相似文献   
996.
997.
Objective To measure the impact of changes in the fraction of inspired oxygen (FiO2) on systemic and cerebral oxygen supply in gas and liquid ventilated healthy animals.Design Interventional prospective animal study.Setting University research laboratory.Participants Ten healthy, new-born piglets.Interventions Variations in FiO2 during conventional mechanical ventilation (CMV) followed by partial liquid ventilation (PLV) with two different filling volumes of PF 5080 (10 vs. 30 ml/kg).Measurements and results Arterial blood gases were obtained 15 min after changing FiO2 and concentrations of cerebral oxygenated and total hemoglobin were determined with near infrared spectroscopy. During CMV an increase in FiO2 1.0 was associated with a constant rise in PaO2 but only a small increase in the cerebral concentration of oxygenated Hb. Initiation of PLV (at FiO2 of 1.0) caused a rapid drop in PaO2 towards values that were similar to CMV at FiO2 of 0.5. At FiO2 of 0.5 a reduction in oxygenated Hb was found in the 30 ml/kg filling group. Complete filling of the lungs with PFC caused a significant drop in total cerebral Hb concentration.Conclusions According to our data, PLV in healthy lungs should be performed with a FiO2 of 1.0 and a small filling volume to avoid deterioration in cerebral oxygen supply.Financial support: The study was supported by a grant of German Ministry of Education and Research (BMBF Perinatale Lunge-01ZZ9511). NIRO 300 was kindly supplied by Hamamatsu Germany.  相似文献   
998.
BACKGROUND: External quality assurance (EQA) programs for diagnostic tests based on nucleic acid amplification have not been widely implemented in clinical laboratories and remain limited to few tests. Development of specific EQA programs based on application-based proficiency testing for any diagnostic molecular target is challenging. Development of EQA trials based on methodologic proficiency testing and directed to the evaluation of analytical aspects common to the majority of PCR-based tests may be valuable. METHODS: We developed an EQA program for evaluation of DNA extraction and amplification and analysis of products after PCR. Participants received a package containing primers and reference materials to evaluate three specific controls for, respectively, DNA extraction (quality and quantity), PCR performance (specificity and efficiency), and interpretation of results after electrophoresis. Each participant was asked to return to the organizers a form with their numerical results and an aliquot of all amplified samples for joint evaluation. RESULTS: Results varied in all phases of the experimental procedure: preamplification, amplification, and post-PCR interpretation. To give a general estimation on the quality of performances for each laboratory, we designed a score scheme in which the results of any specific action were evaluated on the basis of the distribution around the median consensus values. The maximum possible score was 84. On the basis of total score obtained by each laboratory, we created a qualitative ranking list that provided the final interpretation of results as excellent (>63 points; n = 4 laboratories), good (53-63 points; n = 13), sufficient (42-52 points; n = 15), poor (31-41 points; n = 3), and not acceptable (<31 points; n = 4). CONCLUSIONS: This survey demonstrates the importance of EQA trials based on methodologic proficiency testing directed to evaluation of analytical aspects common to the majority of PCR-based tests.  相似文献   
999.
False-positive troponin I attributed to a macrocomplex   总被引:4,自引:0,他引:4  
  相似文献   
1000.
For several years it has been possible to routinely detect numerous mutations in the human genome by different methods. The most common technique is a standard PCR, but real time fluorescence PCR is increasingly being used. The purpose of this paper is to compare these two different techniques from the point of view of reliability, time consumption, and cost. More than 600 DNA samples of prevalence studies and from cancer patients were used to determine mutations in the genes of coagulation factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase using standard PCR. A subset of 132 samples from the same pool was also tested by LightCycler PCR for the same coagulation gene mutations. Originally LightCycler techniques were applied for quantitative PCR by real time fluorescence measuring. Adding a melting curve analysis allows mutation detection. The results were perfectly concordant. The cost for the reagents is nearly the same for both methods but the time consumption for standard PCR is much higher than for the LightCycler method, resulting in higher laboratory personnel costs.  相似文献   
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