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BACKGROUND: Keratinocyte growth factor-2 (KGF-2) also described as fibroblast growth factor-10 (FGF-10) is a newly identified member of the fibroblast growth factor family. KGF-2 is 96% identical to the recently identified rat FGF-10 and specifically stimulates growth of normal human epidermal keratinocytes. The present study was undertaken to examine the effects of topically applied KGF-2 in an incisional wound healing model. KGF-2 treatment resulted in an improvement in incisional wound healing as characterized by an increase in breaking strength, collagen content, and epidermal thickness. METHODS: KGF-2 was topically applied to linear incisions made in the dorsal skin of Sprague-Dawley rats. Biomechanical testing was done using an Instron tensiometer for breaking and tensile strength determinations. Wound collagen content was determined using the Sircol collagen assay. Epidermal thickness measurements were conducted using Masson's trichrome-stained sections of the wound. RESULTS: A single topical application of KGF-2 at the time of wounding resulted in an increase in wound breaking and tensile strength at Day 5 after wounding. Breaking strength of KGF-2-treated wounds was significantly higher compared with the buffer control (1 microgram, 222.1 +/- 13.5 g, P = 0.0007; 4 microgram, 248.7 +/- 15.4 g, P = 0.0001; 10 microgram, 247.2 +/- 21.9 g, P = 0.001; buffer, 141.0 +/- 9.7 g). Epidermal thickness and wound collagen content were significantly increased following treatment with KGF-2. CONCLUSIONS: Based on our findings, KGF-2 is a potent stimulator of wound healing as demonstrated by increased mechanical strength accompanied by an increase in wound collagen content. KGF-2 could be an important cellular mediator responsible for the initiation and acceleration of wound healing and may enhance the healing of surgical wounds. 相似文献
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A gene (AglyA) encoding serine hydroxymethyltransferase of Acinetobacter radioresistens CMC-1 was cloned and sequenced. Nucleotide sequence analysis of AglyA predicted a single open reading frame (ORF) of 1251 bp encoding a 417-amino acid polypeptide. Two putative MetR-like binding sites (5'-TGAAACATGAGCT) and (5'-TGAGCAAAGTTCA), centered at bp -123 and -95 relative to the +1 translation start site were found, which have six out of nine and eight out of nine nucleotides that match to the consensus sequence of Escherichia coli (5'-TGAANNT/ANNTTCA), respectively. The enzyme also showed a high level of homology to other sources of serine hydroxymethyltransferase proteins. 相似文献
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BACKGROUND AND OBJECTIVES: We describe a partnership between family practice residency clinics and a state public health virology laboratory that has produced comprehensive viral respiratory disease education and surveillance. Family practice residents have been provided with education on respiratory viruses and the results of ongoing viral surveillance. The preliminary effects of this program on antibiotic prescribing by senior residents are evaluated in this paper. METHODS: We used a questionnaire to assess the acceptance by family practice residents of the educational component and the utility of ongoing viral surveillance. We used chart review to evaluate rates of antibiotic prescribing and the number of patients diagnosed per year with acute upper respiratory infection and acute bronchitis by senior residents in 1992 (preexposure) and 1996 (postexposure). RESULTS: By the third year of training, most residents (79%) reported receiving adequate training regarding common viral respiratory diseases. Moreover, residents reported that they were less likely to prescribe antibiotics to patients presenting with respiratory infections when provided with specific information on circulating viral pathogens. Antibiotic prescribing in the postexposure group was 68% lower for upper respiratory infection (URI) and 45% lower for a composite of URI and bronchitis. CONCLUSIONS: Education and monitoring of circulating respiratory viruses can result in familiarity with common disorders in primary care and reduce unnecessary antibiotic use. 相似文献
16.
PA Field 《Canadian Metallurgical Quarterly》1994,31(2):201-215
In this survey research a comparison was made between symptoms used by mothers and nurses which led them to think the baby might be "colicky." Two questionnaires, one for mothers and one for nurses, were used to collect the data. The mothers most frequently selected passes gas rectally, clenches fists, draws-up legs, cries late afternoon and evening, holds body straight, and wants to be held. The nurses selected mother states baby is inconsolable, cries more than 4 hours in 24, draws up legs and wants to feed but won't. Parents believed the colic to be related to a variety of factors; these included baby's eating behaviour, maternal anxiety, baby's and mother's diets, and baby's stress. Ten parents reported pain and screaming as symptoms of colic. 相似文献
17.
SD Boden PA Moskovitz MA Morone Y Toribitake 《Canadian Metallurgical Quarterly》1996,21(22):2689-2697
STUDY DESIGN: Cadaveric anatomic and in vivo survival animal studies were performed to develop a new arthrodesis technique for the lumbar spine. OBJECTIVES: To examine the feasibility, efficacy, and safety of a minimally invasive lumbar intertransverse process arthrodesis technique using an osteoinductive growth factor (rhBMP-2) delivered in a collagen sponge carrier. The technique was first developed using a rabbit model and modified for the nonhuman primate (rhesus monkey), a larger animal with the most similar bone biology to humans. SUMMARY OF BACKGROUND DATA: The morbidity of conventional posterolateral lumbar intertransverse process arthrodesis includes graft donor site morbidity; paraspinal muscle devascularization, denervation, and scarring and nonunion in up to 36% of patients. Minimally invasive anterior lumbar interbody arthrodesis techniques have been developed, but these often require a metal implant and carry risks to major vessels and development of retrograde ejaculation. A minimally invasive technique for posterolateral intertransverse process arthrodesis has not been described previously. METHODS: In Part 1, we examined seven New Zealand white rabbits and five rhesus monkeys at necropsy and during nonsurvival surgeries to determine the best access routes and to develop special instruments for video-assisted lateral intertransverse process arthrodesis. In Part 2, 38 New Zealand white rabbits underwent L4-L5 intertransverse process arthrodesis: the "OPEN" group (n = 16) underwent a standard open muscle-splitting approach using rhBMP-2 (bone morphogenetic protein) and collagen as a bone graft substitute; the "video-assisted control" group (n = 6) underwent video-assisted lateral intertransverse process arthrodesis with the collagen implant only (no growth factor); and the "video-assisted-BMP" group (n = 16) underwent video-assisted lateral intertransverse process arthrodesis with rhBMP-2 and collagen as the graft material. In Part 3, rhesus monkeys (n = 4) underwent video-assisted lateral intertransverse process arthrodesis using rhBMP-2 and collagen after laminectomy of L4-L5. RESULTS: In Part 1, we identified expedient, minimally invasive routes to the intertransverse process interval appropriate for each species: an intermuscular approach for the rabbit and a lateral, extramuscular approach for the rhesus monkey. In Part 2, all rabbits in the OPEN and video-assisted-BMP groups achieved solid intertransverse process lumbar fusions when assessed at 10 weeks. There were no neurologic impairments nor any difference between the two groups in the frequency of postoperative infection or other complications. None of the animals in the video-assisted control group showed evidence of fusion. In Part 3, exposure, decortication and grafting with rh-BMP-2 and collagen was accomplished successfully in all four monkeys through the video-assisted minimally invasive approach without complications. CONCLUSION: Video-assisted lateral intertransverse process arthrodesis is a feasible, effective, and safe method of lumbar spinal fusion in the rabbit and rhesus monkey. Use of this arthrodesis procedure will minimize the morbidity of paraspinal muscle denervation and devascularization seen with open intertransverse process fusion techniques, and the use of an osteoinductive growth factor will eliminate the problem of graft donor site morbidity and possibly increase the chances for successful fusion. 相似文献
18.
Sarcomatoid carcinomas (SC) of the lung are the most common pulmonary neoplasms that exhibit a composition by spindled or pleomorphic tumor cells. As such, many of them may be confused easily with true sarcomas diagnostically unless special immunohistological or ultrastructural analyses are performed. Reactivity is expected for keratin, epithelial membrane antigen, or collagen type IV in the sarcomalike elements in SC, although it may be focal. Electron microscopy often shows the presence of junctional complexes between tumor cells, with or without pericellular basal lamina and cytoplasmic skeins of intermediate filaments. Current terminological preferences are such that several formerly used terms--including "spindle-cell carcinoma," "pulmonary blastoma," "squamous cell carcinoma with pseudosarcomatous stroma," "pseudosarcoma," and "carcinosarcoma"--are now encompassed by the more generic designation of "sarcomatoid carcinoma." The clinical course of patients with this neoplasm is aggressive, with an overall 5-year survival rate approximating 20%. 相似文献
19.
JR Passweg PA Rowlings KA Atkinson AJ Barrett RP Gale A Gratwohl N Jacobsen JP Klein P Ljungman JA Russell UW Schaefer KA Sobocinski JM Vossen MJ Zhang MM Horowitz 《Canadian Metallurgical Quarterly》1998,21(12):1231-1238
Most of the previously published surgical series of suprasellar meningiomas have two disadvantages: (1) patients involved were treated within a relatively long time period, making analysis more difficult, (2) radiographic long term follow-up examinations with either CT- or MRI-scans were not performed. Both disadvantages were overcome in our retrospective clinical study, consisting of 50 consecutive patients with suprasellar meningiomas treated between 1982 and 1991. Radiological, ophthalmological, and neurological investigations were performed preoperatively, postoperatively and at long term follow-up (mean: 5.7 years). A radiologically confirmed radical tumour removal could be achieved in 84% of patients. Both, the peri-operative mortality (2%) and serious operative morbidity (6%) were low. However, 12% of patients developed late onset epilepsy. At long term follow-up, visual function was improved in 67%, unchanged in 9% and worsened in 24%. In more than 50% of patients the vision showed recovery over a longer time period than the first 10 days after operation. Radiographic control examinations revealed tumour recurrences in 2 patients (both asymptomatic) and progress of residual tumour in 5 patients (2 symptomatic, 3 asymptomatic). Since introduction of modern neurosurgery, a clear improvement in the surgical treatment of suprasellar meningiomas can be observed. However, the still long delay in diagnosing these tumours correctly prevents a further improvement of the ophthalmological results at long-term follow-up. Due to a relatively high rate of late onset epilepsy, anticonvulsive prophylaxis for 6 months seems to be justified. Regarding present preoperative diagnostic measures, ia-DSA seems only be indicated in patients with CT/MRI-scans, suspicious for tumourous narrowing or invasion of major cerebral arteries. In addition, we recommend radiographic control examinations at regular time intervals to confirm radical tumour removal and to detect the "ideal" point of time for renewed treatment. 相似文献
20.
PA Ringstrom 《Canadian Metallurgical Quarterly》1998,62(3):314-325
The sheer ferocity of competition over needs rarely exhibits itself more than in the consulting room of the conjoint therapist. While cognitive and behavioral therapies may short-circuit this process by negotiating each partner's "fair share" of wishes and responses, such approaches circumvent the examination of the source of such dire competitiveness. Furthermore, they leave the participants with little depth of understanding of what each so vehemently has at stake. In this realm, the psychoanalytic perspective lends a unique vantage point by helping us understand the depth of unconscious need provoked among marital couples or otherwise committed partnerships. 相似文献