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61.
Expression of the fibroblast growth factor 4 (FGF-4) gene is tightly regulated during mammalian development. Dysregulation of FGF-4 gene expression results in cell transformation and tumorigenesis. It is therefore pertinent to investigate the regulatory mechanisms which control expression of FGF-4. In an initial attempt to identify exogenous factors other than retinoic acid which might control FGF-4 expression, we have investigated the response of endogenous FGF-4 to serum in a number of embryonal carcinoma and embryonic stem cell lines. We have identified a human embryonal carcinoma cell line (Tera-2) in which the FGF-4 gene can be induced by serum. In Tera-2 cells made quiescent by serum deprivation, expression of the FGF-4 gene is repressed. Subsequent addition of serum reactivates FGF-LC expression and further addition of cycloheximide results in superinduction of mRNA suggesting that FGF-4 may be classified as an early response gene. It is suggested that this observation may be explained, at least in part, by the stage of differentiation of the Tera-2 cells.  相似文献   
62.
Laparoscopy was used to evaluate 60 patients with a variety of known or suspected gynecologic neoplasms. Diagnostic laparoscopy was performed on 18 patients to confirm benign or malignant pelvic masses or to confirm peritoneal carcinomatosis. Ten of these 18 patients (56%) were found to have unresectable carcinomatosis or benign disease which did not require further surgery. Staging laparoscopy was performed on 13 patients of which 3 had clinically unsuspected intraperitoneal spread of their disease. Surveillance laparoscopy was performed on 29 patients to determine the remission, regression, or progression of their disease following treatment; 8 (27%) had progressive or unresectable persistent disease. Despite the fact that the study comprised a high-risk group of previously operated on or irradiated patients, there was only one major complication. There was, however, a 10% incidence of laparoscopic failure from inadequate visualization. Twenty-one of the study patients (35%) were spared a laparotomy by the use of laparoscopy. The findings of this investigation help to identify those gynecologic oncology patients who should benefit most from the use of laparoscopy as an adjunct to the diagnosis, staging, or surveillance of intraabdominal malignant tumors.  相似文献   
63.
The information sources consumers use and consumers' perceptions of the quality of services they receive are examined in the context of breast augmentation surgery. Consumers who received breast implants for reconstructive purposes (i.e., after a mastectomy) were compared with those who received them solely for cosmetic purposes. Implications for health care marketers at a time of federal scrutiny are discussed.  相似文献   
64.
65.
One hundred and four preterm infants were studied during the first few months of life in the Special Care Baby Unit of Addenbrooke's Hospital, Cambridge, United Kingdom. Previously, it had been the daily practice within the Unit to give a 1 mg oral supplement of folate (in the form of pteroylglutamic acid), once the infants had commenced full enteral feeding. At least one blood sample was obtained from 70 infants before oral folate supplementation was started. In these, the plasma folate levels fell progressively from a median value of 45 g/l to a median of 12 g/l, by the 2nd–3rd week of life. Once started on the oral supplement, 83 of the infants provided at least one blood sample. The plasma folate level of these infants rose immediately to a median value of 300 g/l and a maximum of 1000 g/l. Within individuals, these plasma folate levels decreased progressively following the introduction of the supplement, despite continuing daily supplementation. In a typical baby this decrease appeared to be explained by an increase in body-size, i.e. dilution of the folate into a larger pool. The implications of this level of supplementation are discussed, and in the light of our observations we suggest that daily supplementation in the range, 0.05–0.2 mg folate may be preferable for well preterm infants.  相似文献   
66.
Thirteen hands in 11 patients with previous carpal tunnel releases were treated by microscopic internal neurolysis and palmaris brevis "turnover" flaps. All patients in the series had positive electrodiagnostic testing, dysesthetic wrist pain, and numbness in the median nerve distribution before operation. Average age was 41.9 years (range, 27 to 62 years). Ten were male and 3 were female. Range of follow-up after the procedure was from 1 to 1 1/2 years. All hands with abnormal preoperative two-point discriminations or Semmes-Weinstein measurements showed numerical improvement in their sensory parameters. Thenar strength and bulk improved at least one grade in all six cases of thenar atrophy. Mean grip strength was 15.2% greater than before operation. Key pinch increased 5.5% and pulp pinch 31.9%. Subjective assessment of improvement ranged from 25% to 100%. All patients returned to their former jobs or to vocational retaining except the oldest patient who is semiretired.  相似文献   
67.
The authors describe a family, of which 13 members had peripheral neuropathy manifesting as episodes of paralysies usually provoked by minor compression of nerve trunks. Nerve and muscle biopsies in two patients, demonstrated many thickenings of the myelin sheath ("tomacula"). Electron microscopy investigations are used as a basis for discussing the origin and place of this affection among other hereditary neuropathies.  相似文献   
68.
69.
Primary closure with "minimal tension" of an inadequately debrided massive abdominal wall defect invariably results in further necrosis and dehiscence. Rotation flaps and prosthetic materials are potentially hazardous in severely traumatized and contaminated wounds. An alternate technique, utilizing an abdominal wall pack and porcine skin graft has been used in two patients with close-range shotgun blasts and one patient with postoperative necrotizing fascitis. The combination of a biological dressing and an abdominal wall pack, stinted by strategically placed retention sutures, controls infection, promotes healthy granulation tissue, and prevents bowel erosion with fistula formation.  相似文献   
70.
Subacute combined degeneration (SCD) of the spinal cord is known to present histopathologically degenerative lesions in the spinal cord, but few studies on the neuroradiological findings have so far been reported. We present the interest of initial and follow-up MR findings in three cases of SCD. In the three cases, a causal event precipitated the onset of neurological symptoms: general anesthesia for the first and the third one and folic acid treatment for the second one. Clinical evolution was favorable after specific treatment with nearly total recovery. The initial MR study disclosed lesions predominantly involving the posterior columns of the spinal cord: high intensity on T2 weighted image was seen in the initial MR study and disappeared three months after treatment in correlation with good recovery, but with a delay. The recognition of this MR pattern suggests that MRI may be used in conjunction with clinical assessment to confirm the diagnosis and to monitor the efficacity of treatment in SCD.  相似文献   
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