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71.
R J Sevick A J Barkovich M S Edwards T Koch B Berg T Lempert 《AJR. American journal of roentgenology》1992,159(1):171-175
To characterize further the evolution of white matter lesions in neurofibromatosis type 1, we reviewed 68 MR images in 43 patients (age, 1-31 years), including 25 follow-up studies (mean interval, 27 months). Lesion number, location, morphology, signal characteristics, and contrast enhancement were assessed. Lesion characteristics and changes thereof were correlated with the patients' ages. Thirty-four patients (79%) had white matter lesions. These lesions were hyperintense on T2-weighted images, were isointense on T1-weighted images, and showed no mass effect or contrast enhancement in 31 patients; in three patients, T1-prolongation was observed (one with significant mass effect). None of the lesions evolved into a glioma. The most common locations were the cerebellum (49%), brainstem (22%), and internal capsule (19%). Nineteen patients had white matter lesions and follow-up studies. Lesions decreased in size or number in seven patients (average age, 13 years), showed no change in three (average age, 12 years), increased in size or number in four (average age, 5 years), and showed a mixed pattern (increased/decreased size/number) in four (average age, 7 years). White matter lesions in neurofibromatosis type 1 frequently increase in size or number early in childhood; this did not indicate neoplasia in our study. The lesions tend to resolve with increasing age. Lesion progression in a child more than 10 years old warrants close follow-up to rule out a neoplasm. 相似文献
72.
Role of alginate in infection with mucoid Pseudomonas aeruginosa in cystic fibrosis. 总被引:11,自引:2,他引:9
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BACKGROUND: Chronic bronchopulmonary infection with mucoid, alginate producing Pseudomonas aeruginosa occurs characteristically in patients with cystic fibrosis. Alginate may be a virulence factor for P aeruginosa infection in such patients. METHODS: Forced vital capacity (FVC), nutritional state and the antibody response to P aeruginosa were determined at regular intervals from three years before chronic P aeruginosa infection to 10 years afterwards in 73 patients with cystic fibrosis. All patients were treated intensively with antipseudomonal chemotherapy during the study period. RESULTS: FVC was reduced in all patients who subsequently developed P aeruginosa infection before they acquired the infection, indicating significant pre-existing lung damage when compared with patients who remained free of P aeruginosa. Lung function and nutritional state remained unchanged after 10 years of infection, except in the patients who died of P aeruginosa lung infection. The FVC and height and weight of patients infected with nonmucoid strains of P aeruginosa were similar to those of uninfected patients. Patients infected with mucoid strains had poorer lung function and nutritional state for the first five years after infection compared with patients with nonmucoid strains. Such infection was also associated with greater IgG and IgA antibody responses to P aeruginosa standard antigen compared with nonmucoid infection. Concentrations of antibody to alginate were similar in patients with non-mucoid and mucoid infection. Noticeably increased concentrations of IgA antibodies to P aeruginosa standard antigen were observed early after the onset of infection in patients who subsequently died. CONCLUSION: Alginate producing P aeruginosa infection is associated with a hyperimmune response and poor clinical condition, suggesting that alginate production is a virulence factor in such infections in patients with cystic fibrosis. 相似文献
73.
The Workup for Bariatric Surgery Does Not Require a Routine Upper Gastrointestinal Series 总被引:1,自引:0,他引:1
Andrew J Ghassemian Kenneth G MacDonald MD Paul G Cunningham MD Melvin Swanson PhD Brenda M Brown MRA Patricia G Morris BSN Walter J Pories MD 《Obesity surgery》1997,7(1):16-18
Background: Morbid obesity is a serious disease that afflicts over five million Americans, threatening their health with such
co-morbidities as diabetes, arthritis, pulmonary failure and stroke. Surgery is the only effective therapy, providing long-term
control of weight, diabetes, pulmonary failure, and hypertension for as long as 14 years. Because the operation presents a
major expense, this study examined whether X-ray examination of the gut could be omitted safely as a cost-saving measure.
Methods: The records of 814 consecutive morbidly obese patients who underwent gastric bypass were reviewed to determine: (1)
whether these individuals had undergone an upper gastro-intestinal (GI) series, and (2) if these studies influenced therapy
or caused cancellation or postponement of surgery. Results: Of the 814 patients, 657 (80.7%) underwent a preoperative GI radiography.
Of these examinations, 393 (59.8%) were normal, with the following abnormalities in the remaining 264: hiatal hernia, 164;
esophageal reflux, 39; Schatzki's ring, 18; small bowel diverticula, four; renal stones, four; malrotation, three; gall stones,
two; pyloric ulcer, one; possible pelvic mass, one; calcified leiomyoma, one; and dysphagial lusoria, one. None of these findings
resulted in cancellation or a delay in surgery. Conclusions: The upper GI series can be safely omitted from the routine preoperative
evaluation of patients undergoing gastric bypass. At a cost of $741.00 per examination, this change represents significant
potential savings. Similar evaluations of other routine preoperative tests may well provide a better basis for the evaluation
of these complex patients. 相似文献
74.
A 2?year-old boy had the onset of pain and swelling of his penis during the past 3 days. The swelling and pain increased significantly within the past 24 hours. The child's penis is shown in the Figure. DENOUEMENT AND DISCUSSION PARAPHIMOSIS Paraphimosis is an urologic emergency that results when the foreskin is retracted away from the glans penis and cannot be reduced to its former position. The opening in the prepuce, when forcibly retracted beyond the coronal sulcus, becomes a constricting ring that cannot be reduced. The constricting ring created causes a tension greater than the lymphatic pressure and results in edema of the prepuce, the penile shaft, and the glans penis distal to the incarcerated foreskin.1,2As lymphatic drainage is impaired and tissue swelling increases, reduction of the foreskin becomes more difficult. Pain occurs as a result of swelling, and, eventually, as a result of vascular compromise. If. 相似文献
75.
Zusammenfassung
Operationsziel Schmerzfrei belastungsf?hige Fü?e.
Indikationen Gehen und Stehen schmerzhaft.
Unbefriedigende Einlagen- und Schuhversorgung.
Unbefriedigende ?sthetik.
Kontraindikationen Schlechte Hautverh?ltnisse.
Operationstechnik Dorsaler Zugang beiderseits.
Resektion von intermetatarsalen Knochenbrücken.
Korrekturosteotomien fehlstehender Mittelfu?knochen.
Beseitigung des Hallux varus durch Reposition der Gro?zehe im Grundgelenk und tempor?re Kirschner-Drahtfixation des Gro?zehenstrahls
und der Mittelfu?fragmente.
Ergebnisse Zw?lf Jahre nach den Eingriffen an beiden Fü?en lag ein ?sthetisch und funktionell sehr gutes Resultat vor. Die Patientin
trug normale Kaufschuhe und belastete beide Fü?e tadellos. Die Fü?e konnten allerdings wegen ausgedehnter angeborener Synostosen
der Fu?wurzel- und Tarsometatarsalgelenke nicht befriedigend abgerollt werden. 相似文献
76.
Francisco M. Averhoff Walter W. Williams Stephen C. Hadler 《The Journal of school health》1997,67(7):298-303
SUMMARY: This report concerning the immunization of adolescents (ie, persons 11–21 years of age, as defined by the American Medical Association [AMA] and the American Academy of Pediatrics [AAP]) is a supplement to previous publications (ie, MMWR 1994;43[No. RR-1] 1–38; the AAP 1994 Red Book: Report of the Committee on Infectious Diseases; Summary of Policy Recommendations for Periodic Health Examination, August 1996 from the American Academy of Family Physicians [AAFP]; and AMA Guidelines for Adolescent Preventive Services [GAPS]: Recommendations and Rationale). This report presents a new strategy to improve the delivery of vaccination services to adolescents and to integrate recommendations for vaccination with other preventive services provided to adolescents. This new strategy emphasizes vaccination of adolescents 11–12 years of age by establishing a routine visit to their health-care providers. Specifically, the purposes of this visit are to a) vaccinate adolescents who have not been previously vaccinated with varicella virus vaccine, hepatitis B vaccine, or the second dose of the measles, mumps, and rubella (MMR) vaccine; b) provide a booster dose of tetanus and diphtheria toxoids; c) administer other vaccines that may be recommended for certain adolescents; and d) provide other recommended preventive services. The recommendations for vaccination of adolescents are based on new or current information for each vaccine. The most recent recommendations from AC1P, AAP, AAFP, and AMA concerning specific vaccines and delivery of preventive services should be consulted for details. 相似文献
77.
The forces to produce fractures of the os calcis are combined compression and shear under a cranio-caudal impulse of 10-40 kN and a short time of stroke about 10-40 ms. The main patterns in biomechanics of calcaneal fractures are the time of stroke and the geometrical position of the foot in the moment of impact. Furthermore individual structural changes of the calcaneal cancellous bone, age, diseases as Diabetes mellitus and vascular obliterations are to be respected. Operative treatment of these fractures needs an understanding of the pathomechanism of the intracalcaneal shear-tension-forces. With plantarflexion of the foot combined with vertical forces within 40 ms to the anterior talocalcanear facette impact-fractures of the anterior part can be expected. These forces develop a posterior directed shear tension parallel to the axis of the os calcis, dividing the bone horizontally in two parts (Typ A, 44-56%), well-known as tongue-type fracture. Compression of the posterior talo-calcaneal joint leads to an impact of this structure producing the joint depression type within about 30 ms in dorsoflexion of the foot (Type B, 42%) together with sagittal shear fractures. High-energy forces are supposed to produce the so-called primary fractures of the sustentacular process in about 10 ms in a supinated position of the foot (Type C, 2-10%); these fractures represent in cases of dislocation an indication for open reduction and internal fixation. In our own experience with 45 cases in 35 patients using the lateral or/and medial approach no infection happened. Palmer's lateral approach was preferred. 相似文献
78.
79.
Background: diabetic patients with end-stage renal
failure (ESRD) have a high cardiovascular morbidity and mortality. The
underlying mechanisms are not completely elucidated. The aim of our study
was to define predictors of death in diabetic patients with end-stage renal
disease. Patients and methods: We preformed a
prospective study in 35 dialysis centres in Germany between 1985 and 1994.
To evaluate predictors and risk factors in this population we examined 412
diabetic patients at the time of admission to dialysis treatment
(peritoneal dialysis (PD) or haemodialysis (HD)). Classification of the
type of diabetes was done according the criteria of the National Diabetes
Data Group [1,2]. Items assessed at the time of admission were coronary
artery disease (CAD), peripheral occlusive disease (POD), and stroke. CAD
was defined as a history of myocardial infarction with the corresponding
changes in the ECG or luminal narrowing by more than 50% in at least one
coronary artery upon coronarangiography; POD was defined as claudication
and/or brachial-tibial ratio (BTR) less than 0.9 or a history of
amputation. Assessment of the nutritional state comprised body mass index,
skinfold thickness of the upper arm and lateral thorax area, and urea
concentration. Cholesterol, HDL, LDL, apolipoprotein A (ApoA-I) and B
(ApoB), triglycerides, lipoprotein (a) (Lp(a)), and fibrinogen were
measured. As an index of disturbed cardiac innervation beat-to-beat
variation was measured. Outcome measurements were causes of death (i.e.
cardiac and non-cardiac) and time of survival.
Results: One hundred and eighty of 412 (44%) patients
died during the observation period Patients who died were older
(61±12 versus 53±15 years P
lt;0.0001), had lower skin fold thickness (13.1±6.0
versus 15.1±7.2 mm P <0.04), lower
ApoA-I (100±35 versus 111±32
mg/dl P <0.005) and higher fibrinogen (515±156
versus 451±155 mg/dl P <0.02). Type
II diabetic patients had a lower mean survival time than type I (34
versus 66 months P <0.0006). The mode of renal
replacement therapy (PD or HD) had no adverse effect on survival time.
Survivors less frequently had a history of CAD, POD and stroke than
non-survivors. In multivariate analysis ApoA-I, fibrinogen ,age and stroke
were independent predictors of cardiac and non-cardiac death in diabetic
patients with end-stage renal failure. Lipid values and nutritional state
did not independently predict the overall and cardiovascular mortality.
Conclusion: This study in dialysed diabetic patients
identified several predictors of death, some of which are susceptible to
intervention. 相似文献
80.
E. Wallenböck G. Koch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(5):257-265
The intramedullary tibial nail with a proximal angle according to Herzog was developed in order to facilitate implantation. However, the modified technique of unreamed nailing also required a shift of the point of insertion; as a consequence the proximal angle required a considerable increase in the force necessary to introduce the nail. In a study using four cadaver bones and five commercially available unreamed femoral and tibial nails, the authors demonstrate this considerable increase in insertion force and the development of pressure in the medullary cavity. The measurements made with our experimental setup clearly show that the proximal angle of the unreamed tibial nails available for our series does not have a favourable influence on insertion behaviour. As it appears, it results in an increase in the force required for insertion of the nail, thus also causing a greater strain on the bone and an increase in pressure in the medullary cavity. In contrast, the continuous bend of the nail results in a much smoother course of pressure development in the medullary cavity, which does not reach the same high values as with the unreamed tibial nails, despite the fact that less time is required for insertion of the nail. In our opinion, modification of the axial shape of the nail would result both in better implantability and easier removal. We therefore advocate such a modification of the axial shape of intramedullary tibia nails. 相似文献