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51.
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The University of Oklahoma Medical Center has a comprehensive program of pediatric training, research and patient care. Establishment of the Oklahoma Health Center and its Children's Medical Center on the University campus will provide expanded opportunities for training and research in cooperation with other organizations concerned with child health and development.  相似文献   
53.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
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PURPOSE: The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined. MATERIALS AND METHODS: A prospective randomized, multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm. or less. RESULTS: Of 128 patients enrolled in the study 60 with a mean stone size of 14.43 mm. were randomized to percutaneous stone removal (58 treated, 2 awaiting treatment) and 68 with a mean stone size of 14.03 mm. were randomized to shock wave lithotripsy (64 treated, 4 awaiting treatment). Followup at 3 months was available for 88% of treated patients. The 3-month postoperative stone-free rates overall were 95% for percutaneous removal versus 37% lithotripsy (p <0.001). Shock wave lithotripsy results varied inversely with stone burden while percutaneous stone-free rates were independent of stone burden. Stone clearance from the lower pole following shock wave lithotripsy was particularly problematic for calculi greater than 10 mm. in diameter with only 7 of 33 (21%) patients becoming stone-free. Re-treatment was necessary in 10 (16%) lithotripsy and 5 (9%) percutaneous cases. There were 9 treatment failures in the lithotripsy group and none in the percutaneous group. Ancillary treatment was necessary in 13% of lithotripsy and 2% percutaneous cases. Morbidity was low overall and did not differ significantly between the groups (percutaneous stone removal 22%, shock wave lithotripsy 11%, p =0.087). In the shock wave lithotripsy group there was no difference in lower pole anatomical measurements between kidneys in which complete stone clearance did or did not occur. CONCLUSIONS: Stone clearance from the lower pole following shock wave lithotripsy is poor, especially for stones greater than 10 mm. in diameter. Calculi greater than 10 mm. in diameter are better managed initially with percutaneous removal due to its high degree of efficacy and acceptably low morbidity.  相似文献   
56.

Background

In the United States, cholesterol stones account for 70% to 95% of adult gallstones and black pigment stones for most of the remainder. Calcium carbonate stones are exceptionally rare. A previous analysis of a small number of pediatric gallstones from the north of England showed a remarkably high prevalence of calcium carbonate stones. The aims of this study were to analyze a much larger series of pediatric gallstones from our region and to compare their chemical composition with a series of adult gallstones from the same geographic area.

Methods

A consecutive series of gallbladder stones from 63 children and 50 adults from the north of England were analyzed in detail using Fourier transform infrared microspectroscopy. Demographic and clinical data were collected on all patients. The relative proportions of each major stone component were assessed: cholesterol, protein and calcium salts of bilirubin, fatty acids, calcium carbonate, and hydroxyapatite.

Results

Thirty-nine (78%) adults had typical cholesterol stones, 7 (14%) had black pigment bilirubinate stones, and only 2 (4%) had calcium carbonate stones. In contrast, 30 (48%) children had black pigment stones, 13 (21%) had cholesterol stones, 15 (24%) had calcium carbonate stones, 3 (5%) had protein dominant stones, and 2 (3%) had brown pigment stones. In children, cholesterol stones were more likely in overweight adolescent girls with a family history of gallstones, whereas black pigment stones were equally common in boys and girls and associated with hemolysis, parenteral nutrition, and neonatal abdominal surgery. Calcium carbonate stones were more common in boys, and almost half had undergone neonatal abdominal surgery and/or required neonatal intensive care.

Conclusion

The composition of pediatric gallstones differs significantly from that found in adults. In particular, one quarter of the children in this series had calcium carbonate stones, previously considered rare. Geographic differences are not the major reason for the high prevalence of calcium carbonate gallstones in children.  相似文献   
57.

Purpose

Continuous monitoring tools can be used to monitor surgical outcomes over time. We illustrate the use of CUmulative SUM (CUSUM) charts in monitoring outcomes of Kasai portoenterostomy for treatment of biliary atresia at a supraregional unit.

Methods

Data on 57 consecutive infants who underwent a Kasai portoenterostomy performed by a single surgeon between June 1994 and June 2006 were collected. A procedure was defined as successful if clearance of jaundice (plasma bilirubin level <20 μmol/l) was achieved within 6 months of surgery. We applied cumulative observed-minus-expected, sequential probability ratio test (SPRT), and zero-resetting SPRT CUSUM charts and compared the results with those of standard aggregate data analyses. An expected failure rate of 43.0%, based on the national average failure rate, was used.

Results

The failure rate observed after 57 operations was 29.8%. The zero-resetting SPRT chart indicated a lower-than-expected failure rate earlier than did the aggregate data analyses and any of the other continuous monitoring techniques.

Conclusions

The CUSUM chart method provides ongoing feedback that can be used for continuous monitoring of the outcome of a procedure to ensure that standards of care are maintained. Its use as a routine monitoring tool in pediatric surgery deserves wider recognition.  相似文献   
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OBJECTIVE: To describe the medical and rehabilitation service use of model systems by brain injured participants 1 to 3 months postdischarge from inpatient rehabilitation. DESIGN: Prospective follow-up study. SETTING: Georgia Model Brain Injury System (GAMBIS). PARTICIPANTS: Seventy-three GAMBIS subjects consenting to participate in the utilization substudy. MAIN OUTCOME MEASURES: Receipt of services and intensity of service use. ANALYSIS: Chi-square analysis of receipt of services by severity of injury. RESULTS: The likelihood of service use did not vary with severity of injury. Data suggest that intensity of service use was a function of injury severity. CONCLUSIONS: Subjects with mild and moderate injuries were as likely to use a range of medical and rehabilitation services during the 3-month postdischarge period as those with severe injuries. Traditional rehabilitation services, such as physical therapy, were far more likely to be used, than nontraditional services, such as psychological counseling, in spite of the high level of cognitive and social disability associated with traumatic brain injury.  相似文献   
60.
The aim of this study was to determine the prevalence of urinary incontinence in women with familial dysautonomia (FD). A telephone survey was conducted on 68 known surviving female FD patients over 13 years of age registered with the Dysautonomia Centers in the USA and Israel. The mean age of the surveyed group was 27.1+/-9.8 years and 99% of the patients were nulliparous. The overall reported prevalence of urinary incontinence was 82% (n=56). Of the patients with incontinence, 59% (n=33) reported stress incontinence, 11% (n=6) reported urge incontinence, and 30% (n=17) reported symptoms of both, or mixed incontinence. In most women urinary loss was both small and infrequent, but 36% of women (n=20) with incontinence experienced a loss sufficient to necessitate the use of protection (panty liners, pads or diapers); in 7% (n=4) such loss occurred daily. Twelve per cent of all women with FD surveyed experienced primary nocturnal enuresis and 26% experienced nocturia. The prevalence of urinary incontinence is high in young female patients with familial dysautonomia. Neurophysiologic testing in this population may provide a better understanding of the role of the autonomic nervous system in urinary incontinence.Abbreviations FD familial dysautonomia - MI mixed incontinence - MRI magnetic resonance imaging - SI stress incontinence - UI urge incontinence Editorial Comment: The authors report the prevalence of urinary incontinence in familial dysautonomia. This is fertile area for investigation, given the paucity of information currently available. The subtypes of incontinence bear further comparison to populations without dysautonomia. Additional investigators may wish to study this fascinating area further.  相似文献   
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