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71.
The short-term distribution kinetics of exogenous surfactant distribution after intratracheal instillation was investigated in surfactant-deficient neonatal piglets during assisted conventional mechanical ventilation and by high-frequency jet ventilation using exogenous calf lung surfactant extract (CLSE) labeled with 99mTc. Surfactant deficiency was induced by repeated bronchoalveolar lavage in piglets (1.2 +/- 0.4 kg, 1.4 +/- 0.7 d of age), and the short-term distribution kinetics of instilled, labeled CLSE were followed by gamma radioscintigraphy. Animals ventilated by either conventional mechanical ventilation or high-frequency jet ventilation showed similar improvement in arterial/alveolar oxygen ratios after surfactant replacement therapy (0.47 +/- 0.03 prelavage, 0.09 +/- 0.01 postlavage, 0.36 +/- 0.06 postsurfactant). This correlated directly with dynamic radioscintigraphic results showing that instilled CLSE began to distribute to the lungs within 5 s, and was present in substantial amounts in standardized symmetrical lung fields (central, right, and left; upper and lower) within 20 s of tracheal instillation. Subsequent measurements over 30 min showed continued presence of radiolabeled CLSE in all five areas of the lung, with no significant difference between conventional mechanical ventilation and high-frequency jet ventilation animals. Static (5-min) analyses at the end of this period showed that surfactant had distributed relatively symmetrically with 30% of the CLSE located in central regions, 40% in the upper lobes, and 30% in the lower lobes. In contrast, piglets receiving 99mTc in saline showed nonuniform distribution with multiple filling defects noted throughout the lungs. The rapid kinetics and ventilation independence of CLSE distribution suggest that surfactant spreading phenomena after tracheal instillation may facilitate the delivery of exogenous surfactant into aerated lungs in therapeutic applications.  相似文献   
72.
The ability to maintain effective tidal volume and minute ventilation during resistive loaded breathing depends on both adequate central neural respiratory output response and respiratory system mechanical properties such as respiratory muscle strength and chest wall stability. We hypothesized that chest wall instability limits the ability of the preterm (PT) infant to respond to inspiratory resistive loading (IRL) compared with full-term (FT) infants. To test this hypothesis, we subjected eight FT and 10 PT infants to IRL with loads of 1.3, 2, and 6 times intrinsic lung resistance and measured steady state tidal volume (VT), minute ventilation (VE), and chest wall motion. Thoracoabdominal asynchrony was measured by respiratory inductive plethysmography and quantitated by measuring the phase angle, theta, between rib cage and abdominal motion (0 degrees = synchronous motion, 180 degrees = paradoxic motion). At baseline, VT/kg (mL/kg, mean +/- SEM) was similar between PT (7.0 +/- 0.7) and FT (7.5 +/- 0.5) infants. VE/kg (mL/min/kg) was greater in PT (545 +/- 50) than in FT (385 +/- 33) infants (p < 0.05) as a result of increased respiratory frequency in the former. PT infants demonstrated significantly greater chest wall asynchrony (theta = 38 +/- 9 degrees) than FT infants (theta = 9 +/- 3 degrees) (p < 0.01). With the highest resistive loads, VT decreased significantly in the PT but not the FT infants. Furthermore, during IRL, VE decreased to 417 +/- 50 mL/min/kg (p < 0.05) and theta increased to 56 +/- 7 (p < 0.05) in the PT infants, whereas no significant change in either value was observed in the FT group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
73.
74.
In 1978, the Centers for Disease Control initiated a multicenter prospective study to assess the safety of the various female sterilizing operations and the ways in which they could be made safer. During the first 31 months, 3500 women who underwent interval laparoscopic tubal sterilization by electrocoagulation or Silastic banding without other concurrent operations were enrolled in the study. When a standard definition of complications was used, the overall rate of an intraoperative or postoperative complication was 1.7 per 100 women. Several patients factors increased the risk of complications twofold or more: diabetes mellitus, previous abdominal or pelvic surgery, lung disease, a history of pelvic inflammatory disease, and obesity. There was a fivefold difference in complication rates between procedures performed under general anesthesia and those done under local anesthesia.  相似文献   
75.
BACKGROUND: The purpose of this study was to determine the health status and psychological distress of gunshot injury victims 8 months after hospital discharge. METHODS: Sixty patients admitted to a Level I trauma center for firearm-related injuries were interviewed during their hospitalization and again 8 months postdischarge. Health status was measured using the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36). Symptoms of posttraumatic stress (avoidance and intrusion) were assessed using the Impact of Event Scale. RESULTS: Subjects were predominantly young (mean age, 30 years), male (92%), and African-American (95%). Mean SF-36 scores at follow-up were significantly worse than preinjury scores for all subscales (p < 0.05). Symptoms of posttraumatic stress were common; 39% of respondents reported severe intrusive thoughts and 42% reported severe avoidance behaviors. Admission Injury Severity Scores did not predict poor health status 8 months postdischarge, but intrusion symptoms were strongly associated with lower SF-36 scores. CONCLUSION: Many hospitalized survivors of gunshot injuries report significant long-term declines in physical and/or mental health. Injury severity at hospital admission may not be predictive of long-term health status.  相似文献   
76.
Diana Baumrind's typology of parenting is based on a two-factor model of “control” and “warmth”. Her recommended discipline style, labeled “authoritative parenting”, was constructed by taking high scores on these two factors. A problem with authoritative parenting is that it does not allow for flexible and differentiated responses to discipline situations. It is argued that a simpler, and more adequate, approach would be to switch to a model of discipline with a third factor, labeled “tolerance”. Parents of the most socially competent children are adept at knowing when they have a problem and when they do not. An example of the latter would be when a child expresses negative affect while complying fully with a request. Baumrind's notion of authoritative parenting was a useful “dialectic”, demonstrating that control and warmth are independent and equally necessary behaviors, but it did not go far enough. Baumrind's category of harmonious parenting (high warmth, moderate control, high tolerance), which she sees as an anomaly, should be substituted for authoritative parenting as the preferred discipline pattern.  相似文献   
77.
Positron emission tomography/CT is an established imaging method in the diagnosis and staging of cancers. 18F‐fluoro‐2‐deoxy‐d ‐glucose (FDG) is the most commonly used radiotracer in positron emission tomography/CT. It is a tumour viability agent and usually its uptake within a lesion reflects the presence of a viable tumour tissue. However, false‐positive FDG uptake is known to occur in benign processes of either inflammatory or infectious aetiology. We describe FDG uptake at the site of laparoscopic scar that mimicked Sister Mary Joseph’s nodule in a patient with gastric adenocarcinoma. Here, the knowledge of the patient’s history and subtle imaging findings helped in accurate staging of the patient. In this case report, we emphasize the value of the knowledge of the patient history and awareness of different pitfalls of FDG to achieve a correct diagnosis on positron emission tomography/CT.  相似文献   
78.
Background: Although patients with differentiated thyroid cancer (DTC) of follicular cell origin usually have an excellent prognosis, some patients die from progressive tumor. Numerous postoperative criteria have been used to predict prognosis in patients with DTC. The purpose of this investigation was to determine whether the TNM and metastases, age, completeness of resection, invasion, size (MACIS) classifications predicted survival time and why patients died from DTC. The extent of initial treatment and causes of death were also evaluated in these patients who died from thyroid cancer.

Study Design: Between 1965 and 1995, 102 of 1,224 patients with DTC treated at the University of California at San Francisco (UCSF) and UCSF/Mount Zion Medical Centers died from DTC. Risk factors including age at diagnosis, gender, histologic characteristics, TNM and MACIS classifications, the intervals among initial treatment, recurrence, and death, and the initial and subsequent treatments were documented in these 102 patients.

Results: Among the 102 patients who died of DTC 50% were men and 50% were women. The mean age of patients with DTC at diagnosis was 58 years at recurrence, 62 and 65 years at death. Thirty percent of these patients initially had unilateral thyroid operations and 70% had a bilateral operation. Tumors at presentation ranged from 0.6 to 13.0 cm (mean 4.4 cm); 46% of patients presented with late-stage tumors (TNM stage III, IV; MACIS score > 8). At presentation 46% of the patients had locally recurrent disease or regional metastases and 18% had distant metastases. Patients with persistent disease had a significantly shorter survival time than those with recurrent disease (p < 0.001). Both TNM and MACIS classifications were good predictors of survival time. Reoperations were performed in 51% of papillary, 26% of follicular, and 67% of Hürthle cell thyroid cancer patients. Fifty percent of patients with papillary thyroid cancer, 50% of patients with Hürthle cell thyroid cancer, and 11% of patients with follicular cell thyroid cancer died of locally advanced disease.

Conclusions: As expected, patients with local or regional recurrence and those with TNM stage I or MACIS score < 6 survived longer than patients with distant metastasis and TNM stage III or IV, MACIS score > 6, but some patients thought to be at low risk (TNM stage I; MACIS < 6) also died from thyroid cancer.  相似文献   

79.
BACKGROUND: Gastroschisis is a rare abdominal wall defect. Although the pathogenesis of gastroschisis is unknown, there is some evidence of the genetic etiology of gastroschisis. Recently, a functionally null deletion of the mouse bone morphogenic protein-1 (BMP-1) gene resulted in a phenotype that resembled a human neonate with gastroschisis. BMP-1 thus became the first potential candidate gene for gastroschisis. METHODS: To explore this possibility the authors collected blood samples from 11 patients who had gastroschisis. Mutational analysis of exons 2 to 15 of the human BMP-1 gene was performed using genomic polymerase chain reaction, single-strand conformation polymorphism analysis and direct sequencing methods. RESULTS: No mutation of the human BMP-1 gene was observed in any of these patients. CONCLUSION: Although heterogeneous etiologies might be proposed for gastroschisis, our results provide further evidence of a nongenetic etiology for gastroschisis. J Pediatr Surg 36:885-887.  相似文献   
80.
Background:  Screening for celiac disease (CD) in children with diabetes is controversial because no studies have demonstrated metabolic complications in asymptomatic, seropositive subjects or beneficial effects of dietary intervention.
Objective:  We hypothesized that seropositivity to celiac antigens is associated with decreased growth and bone mineralization in asymptomatic diabetic children.
Design/Methods:  Asymptomatic diabetic children were screened for seropositivity to tissue transglutaminase. Villous atrophy was assessed by small bowel biopsy in a subset of seropositive subjects. We compared measures of growth and bone mineralization in 30 seropositive subjects, and 34 matched seronegative controls.
Results:  Relative to seronegative controls, the seropositive subjects had reductions in insulin-like growth factor (IGF) binding protein 3 z scores (p < 0.05) and bone mineral density (BMD) z scores (p = 0.05). Weight, body mass index, IGF-I, and bone mineral apparent density (BMAD) z scores were marginally lower, but height z scores were comparable. Seropositive patients with severe villous atrophy had lower weight (−0.91 SDs), height (−1.1 SDs), BMD (−2.0 SDs), and BMAD (−2.0 SDs) z scores and significant increases in parathyroid hormone (all p < 0.05). Four patients with severe villous atrophy maintained strict gluten restriction for at least 12 months. Gluten restriction increased BMD and BMAD z scores.
Conclusions:  High-titer seropositivity to celiac antigens is associated with reductions in weight and BMD in diabetic children, justifying screening of high-risk patients. Results suggest that biopsy is required to confirm the diagnosis and assess the severity of CD; those with severe villous atrophy are more likely to have growth failure and osteopenia. Gluten restriction may reverse these complications.  相似文献   
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