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21.
BASIS: Fractures of the talus or calcaneus with accompanying soft tissue damage require precisely planned treatment to prevent infection of the wound over time, especially in severely injured patients. MATERIAL AND METHODS: Seven patients with fractures of the talus or calcaneus and accompanying 2nd and 3rd degree open or 3rd degree closed soft tissue injuries were followed up retrospectively. These patients were operated on between January 1999 and January 2006 with free fasciocutaneous scapular or parascapular flaps. The average age was 34 (range 16-54). Follow-up was at 6-36 months. RESULTS: Osteosynthesis was primarily in six cases, post-primarily in one, and in four cases exterior fixation was used additively. Temporary vacuum therapy was performed for a mean of 28 days (6-42). Parascapular, scapular, and Latissimus dorsi flap coverage was performed six, one, and one times, respectively. Six flaps healed without complication. One necrosis of a parascapular flap occurred and made a Latissimus dorsi flap necessary. In one case of donor-site wound dehiscense, a local rotation flap became necessary. There was no joint infection or osteomyelitis. Bony consolidation was achieved within all fractures. CONCLUSION: Traumatic soft tissue damage must be taken into account when primary or secondary internal fixation is performed and should influence the choice of implant. Free fasciocutaneous parascapular or scapular flaps are a powerful tool for preventing infection if local flaps are not sufficient to achieve stable soft tissue coverage.  相似文献   
22.
OBJECTIVE--To describe the human immunodeficiency virus (HIV) epidemic among socially and educationally disadvantaged young persons in the United States. DESIGN.-We analyzed demographic and geographic findings from the screening of Job Corps students for antibody to HIV. SETTING--The Job Corps is a federal training program for disadvantaged, out-of-school youth. POPULATION SCREENED--Residential students aged 16 to 21 years who entered the Job Corps from October 1987 through February 1990. MAIN OUTCOME MEASURE--Rates of observed HIV infection in entering students, stratified by demographic and geographic features. RESULTS--Of 137,209 Job Corps students screened, 488 were HIV seropositive (3.6 per 1000), a seroprevalence rate higher than that among military applicants of the same age. Overall seroprevalence was slightly higher in male (3.7 per 1000) than in female (3.2 per 1000) Job Corps students, but among those students aged 16 and 17 years, seroprevalence was higher among females (2.3 per 1000) than among males (1.5 per 1000) (P less than .05). For students aged 16 to 21 years, seroprevalence increased with year of age: 1.8 per 1000 per year for males and 0.7 per 1000 per year for females. Among those aged 21 years, HIV prevalence was 8.9 per 1000. For black and Hispanic students from large Northeastern cities, seroprevalence increased by 4.3 per 1000 per year of age and reached 24.8 per 1000 (one of 40) in students aged 21 years. However, among students from rural areas and small towns, HIV seroprevalence was disproportionately high in the Southeast. Compared with recently described US patients with the acquired immunodeficiency syndrome, HIV-infected students who entered the Job Corps were much more likely to be female. CONCLUSIONS--These findings show that disadvantaged, out-of-school adolescents are at high risk for HIV infection. The screening results identified surprisingly high seroprevalence in the southeastern United States and demonstrated a marked shift in the HIV epidemic to young women. Controlling the HIV epidemic among teenagers must include interventions that will reach adolescents early and outside of the formal educational system.  相似文献   
23.
Information on the relative incidence of Crohn's disease and ulcerative colitis was obtained by a prospective investigation at six Melbourne teaching hospitals. One hundred and eleven patients who presented with chronic inflammatory bowel diseases between 1980-1981 were admitted to the study. Forty (36%) patients were diagnosed as having Crohn's disease and 63 (57%) patients as having ulcerative colitis. The type of chronic inflammatory bowel disease could not be determined in eight (7%) patients. These findings suggest that the relative frequency of Crohn's disease and ulcerative colitis in Melbourne hospitals is within the range that is reported for northern Europe and the United States.  相似文献   
24.
Auditory P300 and eye tracking dysfunction in schizophrenic pedigrees   总被引:4,自引:0,他引:4  
Several psychophysiological abnormalities associated with schizophrenia have been proposed as genetic trait markers of vulnerability to the disorder. Smooth pursuit eye tracking dysfunction and abnormal long latency event-related potentials are the most promising candidates. Both are independent of the effects of psychotropic medication or mental state at the time of testing, and twin studies demonstrate that each has a high level of heritability. Having recorded smooth pursuit eye tracking and event-related potentials in 20 high-density schizophrenic families, we find abnormalities in one or both measures in most of the families studied. The abnormalities, when present, occur in the family members with schizophrenia and other forms of functional psychosis, and they have a bimodal distribution with approximately half the nonschizophrenic relatives also showing eye tracking dysfunction and/or abnormal event-related potentials. Some of these relatives had psychiatric symptoms; others were normal. Our results suggest that psychophysiological examination can help to clarify the boundaries of schizophrenia spectrum disorder. By helping to decide the phenotypic status of nonschizophrenic family members, this should increase the power of DNA linkage studies.  相似文献   
25.
26.
Alterations in thyroid hormone status and the administration of radiographic contrast agents can markedly influence iodothyronine metabolism and, in particular, the activity of type I 5'-deiodinase (5'DI). In the present studies, the mechanisms responsible for these effects have been reassessed. As previously reported, the addition of iopanoic acid (IOP) to broken cell preparations resulted in a competitive pattern of 5'DI inhibition. However, the in vivo administration to rats of IOP or 3,3',5'-triiodothyronine (rT3) resulted in a noncompetitive pattern of inhibition of 5'DI in the liver, kidney, and thyroid gland, whereby marked decreases in maximal enzyme velocity (V max) were noted, with no change in the value of the Michaelis-Menten constant. In rats rendered hyperthyroid by the injection of 3,5,3'-triiodothyronine (T3), 5'DI activity was significantly increased in the liver and the kidney. The administration of IOP to these thyrotoxic animals resulted in a rapid loss of enzyme activity characterized by an approximate 80% decrease in 5'DI V max values in both tissues. Furthermore, this inhibitory effect persisted for longer than 60 h after a single IOP injection. IOP administration also decreased 5'DI V max levels in the thyroid gland by 52%. In other experiments, treatment of intact Reuber FAO hepatoma cells with IOP or rT3 induced a rapid decrease in 5'DI V max levels. In cells treated with cycloheximide, these agents enhanced the rate of disappearance of enzyme activity by greater than 12-fold, indicating a predominant effect on accelerating the rate of enzyme inactivation and/or degradation. These studies demonstrate that iodothyronines and other iodinated compounds have complex regulatory effects on 5'DI that entail alterations in the rates of both enzyme activation and inactivation. The previously accepted concept that rT3 and IOP impair thyroxine (T4) to T3 conversion in vivo by acting as competitive inhibitors is an oversimplification. Rather, the clinically beneficial effects of administering these agents to patients with hyperthyroidism may result primarily from the rapid and prolonged inactivation of 5'DI which occurs in the thyroid gland and peripheral tissues.  相似文献   
27.
Pediatric liver transplant recipients constitute a population characterized by a particularly unpredictable and poor bioavailability of cyclosporin (CyA). Even though several adult studies show that the new oral formulation of CyA, Neoral (NEO), produces better bioavailability and blood level predictability, few data describe its pharmacokinetics in children. We performed a complete analysis of the pharmacokinetics of NEO in ten small children after primary liver transplantation. Three pharmacokinetic profiles were set up with data obtained from tests taken during i. v. administration of CyA, after the first oral NEO dose, and after the last NEO dose before discharge from the hospital. The mean half-lives obtained were 8.1, 7.7, and 6.9 h, respectively, and the bioavailabilities were 22 % and 21 % for the first and last NEO doses. A large interpatient variability was observed. This was due, in part, to episodes of diarrhea that interfered with the pharmacokinetic evaluation and, in part, to the variability of post-transplant hepatic function. There was a good correlation between CyA trough levels and their related AUCs for both NEO profiles (r = 0.93 and r = 0.74, respectively). We conclude that, even though the pediatric OLT population remains more unpredictable than that of adults, NEO has a relatively rapid half-life and a remarkably improved bioavailability. Received: 29 November 1996 Received after revision: 10 April 1997 Accepted: 15 May 1997  相似文献   
28.
Cytokines are extracellular mediators which co-ordinate the immune system and which are essential for several differentiation processes e.g.hematopoiesis.Cytokines bind to specific receptors on the surface of target cells thereby initiating an intracellular signalling cascade leading to cytokine- and cell-specific reactions.The cytokine network is characterised by diverse regulation mechanisms and by the close interaction of different cytokine systems.Interaction and regulation takes place at the level of cytokines, its receptors and at the level of intracellular signal transduction molecules.The resulting network allows the co-ordinated response of different cell types and tissues to environmental changes.A detailed knowledge of this “language of the immunsystem” may reveal many new therapeutical strategies for the treatment of inflammation, autoimmune disease or neoplasia.  相似文献   
29.
30.
Sixteen dogs had one tibia filled with acrylic PMMA bone cement and the opposite, control tibia filled with inert bone wax. After 1, 4, and 12 weeks, the blood perfusion in diaphyses was measured with Sc-46 labeled microspheres. The blood flow rates increased from 1 to 4 weeks and dropped to about the 1-week level after 12 weeks on both sides, with the acrylic side lower than the control side. On both sides, Disulphine Blue staining of the bones showed severe endosteal avascularity after 1 and 4 weeks and massive periosteal apposition after 4 and 12 weeks. The initial increase in blood flow is considered due to periosteal apposition, and the differences in blood flow rates are attributed to avascularity caused by the polymerization heat and toxicity of the acrylic cement.  相似文献   
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