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21.
Chronic wounds create a formidable clinical problem resulting in considerable morbidity and healthcare expenditure. The etiology for wound healing impairment appears to be multifactorial; however, ischemia is a common factor in most types of chronic wounds. Ideal therapy for such wounds would be to correct deficiencies in growth factors and matrix components and provide cellular precursors required for timely wound closure. We hypothesized that stromal progenitor cell (SPC) therapy could correct the ischemic wound-healing defect through both direct and indirect mechanisms. To test this hypothesis, we used the ischemic rabbit ear model of chronic wound healing. We found that treatment of the wounds with SPCs was able to reverse the ischemic wound-healing impairment, with improved granulation tissue formation and reepithelialization compared with vehicle or bone marrow mononuclear cell controls. In vitro, SPCs were found to produce factors involved in angiogenesis and reepithelialization, and extracellular matrix components, providing evidence for both direct and indirect mechanisms for the observed correction of the healing impairment in these wounds. Treatment of ischemic wounds with SPCs can dramatically improve wound healing and provides a rationale for further studies focused on SPCs as a potential cellular therapy in impaired wound healing.  相似文献   
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Freiberg's infraction is an ostechondrosis of a lesser metatarsal head resulting in degeneration of the metatarsophalangeal joint. Several mechanisms have been suggested in its pathenogenesis. Freiberg first described the entity and believed single impact trauma was the underlying cause. Repetitive biomechanical microtrauma is the most widely accepted etiologic theory. Other factors contributing to its development include aseptic necrosis, ischemia, and a congenital predisposition. We present a case report of Freiberg's infraction occurring in identical twins involving multiple metatarsals in various stages of degeneration. One of the twins was affected unilaterally whereas the other twin was affected bilaterally. Both twins had involvement of the second metatarsal on the same side extremity. The occurrence of Freiberg's infraction in identical twins suggests that an underlying congenital predisposition to the condition may play more of a role than previously considered.  相似文献   
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Cerebrospinal fluid (CSF) from 7 patients with infantile spasms (mean age: 6.7 months) was collected before and after treatment with adrenocorticotropic hormone (ACTH). The concentration of neurotransmitter metabolites was analyzed using high-performance liquid chromatography and compared to the metabolite concentration in the CSF from 7 age-matched controls (mean age: 6.1 months). Pretreatment levels of CSF 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid, 3-methoxy-4-hydroxyphenyl glycol (MHPG), and kynurenine were significantly lower in infantile spasm patients compared to controls. Following treatment, marked increases in 5-HIAA and decreases in kynurenine levels were observed in the CSF of the 5 infants whose seizures were eliminated or reduced by ACTH. In the 2 nonresponders 5-HIAA levels decreased. The level of MHPG was reduced slightly in 5 infants, including the 2 nonresponders, and was increased in 2 responders. CSF homovanillic acid levels increased in 4 infantile spasm infants and decreased in 3 following ACTH. These data demonstrate that the presence of seizures in infantile spasms is associated with a significant decrease in serotonergic activity and that elimination of seizures by ACTH is accompanied by increased serotonin turnover. The simultaneous increase of 5-HIAA and decrease of kynurenine, an alternate metabolite of tryptophan, suggests an underlying disturbance of tryptophan metabolism in infantile spasms. The possibility that elimination of seizures by ACTH may be related to decreased production of certain kynurenine metabolites, particularly quinolinic acid, is discussed.  相似文献   
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A. S. C. Rice  MB  BS  Registrar  F. Reynolds  MD  FFARCS 《Anaesthesia》1987,42(12):1320-1323
Forty women who underwent gynaecological surgery were randomly allocated to receive trichloroethylene, enflurane, or enflurane plus fentanyl as adjuncts to nitrous oxide/relaxant anaesthesia with controlled ventilation. No serious cardiac dysrhythmias were seen in any group. Each patient was observed postoperatively for 4 hours by a nurse blind to the technique used, and questioned at 24 hours by a similarly blinded anaesthetist. Recovery after trichloroethylene was not significantly prolonged although postoperative analgesia by visual analogue was better, opiate analgesia was required less frequently and there was less nausea and vomiting than in either of the enflurane groups. We argue for the continued use of trichloroethylene by this technique, because it costs one hundred times less than enflurane and because of the potential morbidity of the postoperative opiate dosage required after enflurane.  相似文献   
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OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.)  相似文献   
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Patients'attitudes to rectal drug administration   总被引:2,自引:0,他引:2  
H.A.L. Vyvyan  MB  BS  FRCA  Z. Hanafiah  MB  BS  FFARCSI 《Anaesthesia》1995,50(11):983-984
One hundred adult patients attending for day case surgery were surveyed by anonymous questionnaire in order to determine their attitudes to rectal drug administration. Fifty four patients did not want an analgesic drug (diclofenac sodium) administered rectally whilst under anaesthesia, all preferring to take it orally if available. Ninety eight patients thought that drugs administered per rectum should always be discussed with them beforehand and a few had very strong feelings about this route of administration. We suggest that prescribers of rectal diclofenac should always discuss it with patients pre-operatively. Whilst many are happy to have suppositories, some young patients are sensitive about this and prefer to take such medication by mouth.  相似文献   
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