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1.
1. Alveolar macrophages (AM phi) exhibit arginase activity and may, in addition, express an inducible form of nitric oxide (NO) synthase (iNOS). Both pathways may compete for the substrate. L-arginine. The present study tested whether two recently described potent inhibitors of liver arginase (N omega-hydroxy-D,L-indospicine and 4-hydroxyamidino-D,L-phenylalanine) might also inhibit arginase in AM phi and whether inhibition of arginase might affect L-arginine utilization by iNOS. 2. AM phi obtained by broncho-alveolar lavage of rat and rabbit isolated lungs were disseminated (2.5 or 3 x 10(6) cells per well) and allowed to adhere for 2 h. Thereafter, they were either used to study [3H]-L-arginine uptake (37 kBq, 0.1 microM, 2 min) or cultured for 20 h in the absence or presence of bacterial lipopolysaccharide (LPS). Cultured AM phi were incubated for 1 h with [3H]-L-arginine (37 kBq, 0.1 microM) and the accumulation of [3H]-L-citrulline (NOS activity) and [3H]-L-ornithine (arginase activity) was determined. 3. During 1 h incubation of rabbit AM phi with [3H]-L-arginine, no [3H]-L-citrulline, but significant amounts of [3H]-L-ornithine (150 d.p.m x 1000) were formed. N omega-hydroxy-D,L-indospicine and 4-hydroxyamidino-D,L-phenylalanine, present during incubation, concentration-dependently reduced [3H]-L-ornithine formation (IC50: 2 and 45 microM, respectively). 4. N omega-hydroxy-D,L-indospicine (up to 100 microM) had no effect on [3H]-L-arginine uptake into rabbit AM phi, whereas 4-hydroxyamidino-D,L-phenylalanine caused a concentration-dependent inhibition (IC50: 300 microM). 5. Rat AM phi, cultured in the absence of LPS, formed significant amounts of [3H]-L-citrulline and [3H]-L-ornithine (133 and 212 d.p.m x 1000, respectively) when incubated for 1 h with [3H]-L-arginine. When AM phi had been cultured in the presence of 0.1 or 1 microgram ml-1 LPS, the formation of [3H]-L-citrulline was enhanced by 37 +/- 8.3 and 99 +/- 12% and that of [3H]-L-ornithine reduced by 21 +/- 8.7 and 70 +/- 2.5%, respectively. 6. In rat AM phi, cultured in the absence or presence of LPS, N omega-hydroxy-D,L-indospicine (10 and 30 microM) greatly reduced formation of [3H]-L-ornithine (by 80-95%) and this was accompanied by increased formation of [3H]-L-citrulline. However, only 20-30% of the [3H]-L-arginine not metabolized to [3H]-L-ornithine after inhibition of arginase was metabolized to [3H]-L-citrulline, when the AM phi had been cultured in the absence of LPS (i.e. low level of iNOS). On the other hand, when the AM phi had been cultured in the presence of LPS (i.e. high level of iNOS), all the [3H]-L-arginine not metabolized by the inhibited arginase was metabolized to [3H]-L-citrulline. 7. In conclusion, N omega-hydroxy-D,L-indospicine is a potent and specific inhibitor of arginase in AM phi. In cells in which, in addition to arginase, iNOS is expressed, inhibition of arginase can cause a shift of L-arginine metabolism to the NOS pathway. However, the extent of this shift appears to depend in a complex manner on the level of iNOS.  相似文献   

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Diaphragmatic dysfunction is a common postoperative complication of cardiac surgery in children, with important effects on respiratory morbidity. Its early diagnosis, followed by prompt surgical intervention, has been shown to reduce morbidity. However, the commonest method of diagnosis, based on hemi-diaphragmatic elevation on the chest radiograph, may be less accurate than direct techniques for assessing phrenic nerve function. We have compared electrophysiological and radiological diagnoses of diaphragmatic abnormality in 100 children (aged 3 days to 17.5 yrs) undergoing cardiac surgery, looking at respiratory morbidity as assessed by the duration of ventilation, the time spent on the cardiac intensive care unit (CICU), and the requirement for reintubation. Despite showing good reproducibility, radiological diagnosis was neither sensitive nor specific in identifying patients with electrophysiological phrenic nerve damage. Analysis of the measures of outcome supported the electrophysiological technique. Patients with electrophysiological evidence of damage had a longer duration of ventilation, spent longer on the CICU, and had a greater incidence of reintubation than either radiologically abnormal or "normal" patients. Chest X-rays are not a good method for diagnosing phrenic nerve damage in the early postoperative period in children. If early diagnosis is needed, then direct assessment of phrenic nerve function, such as the measurement of phrenic latency, may be a better technique.  相似文献   

4.
The main symptom of the congenital diaphragmatic hernia (CDH) is the respiratory distress due to the pulmonary hypoplasia and the persistence of foetal pulmonary circulation. Sometimes the CDH appears outside of the neonatal period with respiratory symptoms, abdominal pain and seldom with intestinal obstruction. A case of CDH presenting with intrathoracic volvulus is reported. This case shows that tendency of delayed repair until the newborn has been recovered, require more attention because the good condition of the patient can be changed not only by the pulmonary hypoplasia and the persistence of the foetal pulmonary circulation but also by the symptoms of the intrathoracic gut complications.  相似文献   

5.
The aim of this study was to compare our computer-aided report writing system to standard techniques. A computer-aided reporting system for reporting on chest X-rays was developed and linked with a UNIX-based radiology information system. The reporting system consists of different text modules which can be composed to a complete radiological report. The quality of the report, the system's efficiency, flexibility and availability at the radiology information system (RIS), as well as its acceptance by the users, were criteria we took as a basis of evaluation. Acceptance and flexibility of the system were tested by assessing necessary changes and additions performed to text modules and by subjective evaluation. The time spent on working with the reporting system was evaluated by performing a time-analysis study comparing the new system to the two conventional methods, the tape system and handwriting. On average, the readers needed 22.6 text modules for each report. For the users the most important advantages of the new system are that primarily fewer changes to or additions to the text are necessary, and when they cannot be avoided they can be performed more easily. In comparison with the tape system and handwritten reports, it took on average two and a half to three times longer to report on a chest X-ray. The printed report had left the department within 6.4 h using the tape system within 0.4 h when handwritten and within 1.4 h when recorded by the reporting system. The completeness of the set of modules and the logical order were positively assessed by the users. The demand of time for reporting increases, but the final report is available sooner.  相似文献   

6.
Bochdalek hernia is a posterolateral defect in the embryogenesis of the diaphragm. Abdominal contents enter the thorax during fetal development and result in pulmonary hypoplasia. A cause of respiratory distress in the newborn, the management of this disease has undergone dramatic changes. The defect requires surgical repair, but success depends more on preoperative and postoperative management of the associated physiologic derangements.  相似文献   

7.
Congenital diaphragmatic hernia carries a high mortality which is often the consequence of associated anomalies. A chromosomal abnormality of the long arm of chromosome 8 resulted in a fatal combination of anomalies associated with CDH.  相似文献   

8.
Examined resistance to extinction of a food-motivated response in a total of 78 male albino Wistar rats with sham operations or bilateral dorsal hippocampal, ventral hippocampal, or combined dorsal and ventral hippocampal lesions in 2 experiments. Surgery occurred either before or after acquisition of the to-be-extinguished response. Ss with combined hippocampal lesions showed greater resistance to extinction than controls if acquisition occurred preoperatively, but less resistance if acquisition occurred postoperatively. Ss with ventral hippocampal lesions were affected in a similar manner but to a lesser degree by differential prior experience. In contrast, dorsal hippocampal-lesioned Ss exhibited no change in approach latency during extinction, irrespective of the timing of surgery. It is suggested that both ventral and combined hippocampal lesions interfere with the changing of an established approach "set." (French summary) (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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We present a case of missed diaphragmatic rupture which was treated thoracoscopically. Rupture of the diaphragm is a serious complication of blunt trauma. The diaphragmatic injury can easily be overlooked. This report illustrates the diagnostic dilemma in a patient where the injury was missed at the time of initial presentation. The role of thoracoscopy both for diagnosis and therapy is discussed.  相似文献   

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Despite many advances in the management of congenital diaphragmatic hernia (CDH), the condition carries a mortality rate of 40-50% usually consequent to pulmonary hypoplasia and/or persistent pulmonary hypertension. Several centers have reported improved survival with preoperative stabilization and delayed surgery, which is now an accepted method of management. This is a retrospective analysis of all neonates with respiratory distress at birth due to CDH who were treated at our institution with neither extracorporeal membrane oxygenation nor nitric oxide being used. The medical records of all neonates with CDH and respiratory distress at birth who were treated at this institution from August 1, 1992 through March 1, 1997 were reviewed. There were 21 patients, 11 male and 10 female. There were 17 full-term and 4 premature infants; two premature infants at 30 and 34 weeks' gestation were not resuscitated because of severe associated congenital anomalies. Surgery was performed from 5 to 144 hr (mean 45 hr) in 18 infants. One infant died during preoperative stabilization from severe pulmonary hypoplasia and pulmonary hypertension and one infant died postoperatively from the same conditions. Seventeen of 19 infants (89.5%) survived and were discharged home. Three infants (17.6%) who failed to thrive due to severe gastroesophageal reflux (GER) required fundoplication. Eleven infants (64.7%) who had sepsis proven by blood culture responded satisfactorily to appropriate antibiotics. Preoperative stabilization and delayed surgery has been a satisfactory form of management in our series. The significant complication was sepsis, which must be addressed.  相似文献   

13.
This report describing the radiology of transsphenoidal hypophysectomy based on a review of 100 consecutive surgical procedures. Preoperative laminographic evaluation of the sphenoid sinus is an important aid in planning the most direct surgical approach to the pituitary. It is also useful in defining the many anatomic structures that may be injured inadvertently at the time of surgery. Intraoperative radiography or fluoroscopy is helpful in identifying the sella floor and as an aid in preventing loss of orientation within a capacious sinus. Various changes occur within the sphenoid sinus following surgery, some transient and others persistent. The surgical defect is usually difficult to identify on routine roentgenograms but is clearly visible on lateral laminography. A persistent soft tissue mass within the sinus is usually a manifestation of fascia and fat placed as a seal within the sinus.  相似文献   

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The aim of the study was to assess the efficacy of the preoperative sodium Naproxen administration to reduce analgesic requirements in the postoperative period. 75 patients (ASA I-II), 50 male and 25 female, aged between 25 and 70 years and weighed between 50 and 90 kg, undergoing lumbar laminectomy were subjected to the same anesthetic technique. Patients were allocated randomly to one of three groups. Group I received intravenous sodium naproxen (550 mg) immediately after induction of anesthesia. Group II received intravenous sodium Naproxen (550 mg) at the end of surgery. Group III received intravenous normal saline immediately after induction of anesthesia. Postoperative every patient was given by request intramuscular Buprenorphine (0.3 mg) for pain relief (at 6 h intervals). Buprenorphine requirements in the group I were significantly lower than in either of the other groups (p < 0.01 and p < 0.0001 respectively), while significant differences were not observed between group II and III. Moreover the 54% of patients in the group I did not require analgesic drugs in the postoperative period in opposition to the 20% of pts. in the group II and the 12% of pts. in the group III (p < 0.05 and p < 0.01 respectively). We conclude that NSAIDs when given before tissue damage may prevent nociceptor sensitisation and probably reduce hyperexcitability of the spinal cord. Preoperative administration of NSAIDs provides better protection against peripheral nerve sensitisation than postoperative administration.  相似文献   

16.
BACKGROUND AND AIMS OF THE STUDY: Between January 1990 and July 1995, 108 patients underwent the Ross operation at our hospital. Most patients (90%) had severe aortic regurgitation (AR) in the setting of rheumatic heart disease. Although there have been no perioperative or late cardiac deaths, 12 patients (11%) developed severe AR requiring reoperation. MATERIAL AND METHODS: We performed an extensive and mostly retrospective analysis of echocardiographic data on all patients. Preoperative data were analyzed for age, sex, body surface area (BSA), size and comparison of the left and right ventricular outflow tracts (LVOT, RVOT), left ventricular (LV) size and function, and the presence of pulmonary regurgitation (PR) and concomitant mitral regurgitation (MR). Follow up data were analyzed for the presence, time of onset, evolution and severity of AR, characteristics of the AR jet, anatomic and functional aspects of the aortic root and valve, and evolution of LVOT diameter and LV size and function. RESULTS: Patients with autograft failure were younger with smaller BSA, larger indexed size of LVOT, RVOT and LV, and significantly more had concomitant severe MR. Postoperatively they had larger and increasing LVOT size. Trivial or mild AR was common and seen in almost all patients, as was a minimal degree of preoperative PR. Severe AR developed mostly after the first year of follow up, and reoperation was performed within three years in 11/12 patients. In nine patients cusp dilatation and prolapse (most frequently of the posterior cusp) was the cause of the AR, and rheumatic activity in three. Reoperation was not associated with mortality. CONCLUSION: In our population autograft failure seems to be related to age, BSA and (indexed) LVOT, RVOT and LV size, but only the presence of significant concomitant mitral regurgitation before surgery was identified as a predictor for reoperation. Prolapse of one or more cusps were the cause of the AR in most patients. The graft is sensitive for recurrent rheumatic activity.  相似文献   

17.
Congenital microgastria is an uncommon result of impairment of normal foregut development. To date, only 39 cases have been described in the literature. We report a boy born with microgastria and bilateral hypoplastic kidneys who had feeding problems, resulting in failure to thrive and growth retardation. After a short period of conservative management, he was operated upon at the age of 11 months. A Hunt-Lawrence pouch was created, leading to toleration of increasing amounts of oral feeding. Although his feeding problems have decreased, his height and weight are below normal (<10th percentile). The embryology, clinical presentation, diagnostic procedures, associated anomalies, and management are discussed.  相似文献   

18.
BACKGROUND: Repair of congenital diaphragmatic hernia (CDH) has changed from an emergent procedure to a delayed procedure in the last decade. Many other aspects of management have also evolved since the first successful repair. However, most reports are from single institutions. The lack of a large multicenter database has hampered progress in the management of congenital diaphragmatic hernia (CDH) and makes determination of the current standard difficult. METHODS: The CDH study group was formed in 1995 to collect data from multiple institutions in North America, Europe, and Australia. Participating centers completed a registry form on all live-born infants with CDH during 1995 and 1996. Demographic information, data about surgical management, and outcome were collected for all patients. RESULTS: Sixty-two centers participated, with 461 patients entered. Overall survival was 280 of 442 patients (63%) where survival was recorded. The defect was left-sided in 78%, right-sided in 21%, and bilateral in 1%. A subcostal approach was used in 91% of patients, with pleural drainage used in 76%. A patch of some kind was used in just over half (51%) of the patients, with polytetrafluoroethylene being the most commonly used material (81%) in those patients with a patch. The mean surgical time was 102 minutes, with an average blood loss of 14 mL (range, 0 to 500 mL). The overwhelming majority of patients underwent repair between 6:00 AM and 6:00 PM (289 of 329, 88%). Nineteen percent of patients had surgical repair on extracorporeal membrane oxygenation (ECMO) at a mean time of 170 hours into the ECMO course (range, 10 to 593 hours). The mean age at surgery in patients not treated with ECMO was 73 hours (range, 1 to 445 hours). CONCLUSIONS: The multicenter nature of this report makes it a snapshot of current management. The data would indicate that prosthetic patching of the defect has become common, that after-hours repair is infrequent, and that delayed surgical repair has become the preferred approach in many centers. Furthermore, the mean survival rate of 63% indicates that despite decades of individual effort, the CDH problem is far from solved. This highlights the need for a centralized database and cooperative multicenter studies in the future.  相似文献   

19.
BACKGROUND: Preclinical studies in experimental animals suggest that preemptive analgesia may improve postoperative pain management. The beneficial effects of preemptive analgesia appear less remarkable clinically. The purpose of this study is to examine the effect of pre- and post-incision administration of intrathecal bupivacaine and intrathecal morphine in a rat model for postoperative pain. METHODS: Rats with intrathecal catheters were anesthetized with halothane, and the surgical field was prepared. A saline vehicle or the test drug was administered 15 min before an incision was made in the plantar aspect of the hindpaw or after the incision was completed. After recovery, mechanical hyperalgesia to punctate and nonpunctate stimuli was measured. Rats were tested on the day of surgery for the first 5 h and each day for 6 days. RESULTS: In saline vehicle-treated rats, the median withdrawal threshold decreased from 522 mN to 54 mN or less, and the response frequency to pressure from application of the plastic disc increased from 0 +/- 0% to 96 +/- 12% or greater after incision. Hyperalgesia was persistent through 2 days after surgery and then gradually returned toward preincision values over the next 4 days. Pre- or postincision administration of either intrathecal morphine or intrathecal bupivacaine reduced hyperalgesia on the day of surgery; at all subsequent times, there were no differences between the saline vehicle groups and the drug treatment groups. There were never any significant differences between pre- and postincision treatments. CONCLUSIONS: Early reduction in pain behaviors either by pre- or postincision management had no impact on subsequent measures of hyperalgesia in this model. These results agree with a number of clinical studies and suggest that incisional pain may be initiated and maintained differently than pain in other models.  相似文献   

20.
This study compared the efficacy and tolerability of nisoldipine coat core (CC) 10-40 mg o.d. and hydrochlorothiazide (HCTZ) 25-50 mg o.d. Patients with mild-to-moderate essential hypertension received either nisoldipine CC 10 mg o.d. or HCTZ 25 mg o.d. Treatment was titrated at two-weekly intervals as necessary. The primary efficacy endpoint was a defined reduction in diastolic blood pressure (DBP). Response rates were similar for both the nisoldipine CC- and HCTZ-treated groups (74% and 70%, respectively). Secondary efficacy endpoints were reductions in both diastolic and systolic blood pressures (SBP). At treatment endpoint, the change from baseline in SBP was 16.2 mmHg for the nisoldipine CC group and 14.9 mmHg for the HCTZ group. Both drugs were well tolerated, and adverse events were generally minor and typical of these antihypertensive agents. Drug-related adverse events were greater in the nisoldipine CC- than the HCTZ-treated patients (50% and 37%, respectively). Nisoldipine CC was shown to demonstrate antihypertensive efficacy similar to HCTZ in the treatment of mild-to-moderate hypertension.  相似文献   

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