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991.
N Pasetto V Petrozza C Ticconi A Zicari F Carpino E Piccione M Melis 《Canadian Metallurgical Quarterly》1993,35(2):99-102
Ten patients with biopsy verified chronic hepatitis C virus (HCV) infection were treated with oral ribavirin at a dose of 1,000-1,200 mg per day in two divided doses for 12 weeks. Serum alanine aminotransferase (ALT) levels and hepatitis C viral ribonucleic acid (RNA) levels in serum were followed prior to, during, and 12 weeks posttreatment. ALT levels decreased significantly in all patients during therapy from a mean level of 3.21 mukat/l (range 1.22 to 7.79) before, to 1.25 mukat/l (range 0.78 to 2.04) at the end of treatment (P < 0.005). Hereafter, relapse to pretreatment levels was seen within 12 weeks after treatment stop. The hepatitis C viral RNA levels decreased from a mean 10 log titer of 4.1 (range 1-6) before treatment to 3.4 (range 1-5) at treatment stop. Five patients did not change their HCV RNA titers during treatment. Twelve weeks posttreatment only 3 patients had lower titers than prior to treatment. We conclude that oral ribavirin seems to reduce the viral load, at least temporarily, in some patients with chronic viremic HCV infection. Further studies are needed to evaluate fully the effect of oral ribavirin on chronic HCV infection. 相似文献
992.
The conclusions clinicians have drawn about Holocaust survivors over the last 50 yrs differ sharply from researchers' findings. It is important to evaluate these discrepancies since different perceptions of survivors affect treatment approaches. The researchers' view, stressing the survivor's resilience and resourcefulness, contrasts with clinical impressions centering on a survivor syndrome involving deep emotional disturbances as residues of the Holocaust experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
SF Breniere MF Bosseno C Barnabe S Urdaneta-Morales M Tibayrenc 《Canadian Metallurgical Quarterly》1993,88(1):163-165
Detection of a nondistended pyriform sinus on cross-sectional imaging studies represents a diagnostic dilemma. The finding may be an inconstant physiologic phenomenon without clinical significance, or it may be due to tissue thickening and lack of pliability related to neoplasia or inflammation. Rescanning during respiratory maneuvers may clarify the anatomy, but full patient cooperation is needed. We demonstrate a method (turning the patient's head away from the side of the nondistended sinus) that induces distention of the pyriform sinus but does not require active patient participation. 相似文献
994.
Evaluation of hydroxylapatite/poly(l-lactide) composites: physico-chemical properties 总被引:7,自引:0,他引:7
C. C. P. M. Verheyen C. P. A. T. Klein J. M. A. De Blieck-Hogervorst J. G. C. Wolke C. A. Van Blitterswijn K. De Groot 《Journal of materials science. Materials in medicine》1993,4(1):58-65
The aim of this in vitro study was to examine the physico-chemical behaviour of hydroxylapatite/poly(l-lactide) (HA/PLLA) composites in solution tests. The polymer PLLA, the composites 30 wt% HA/PLLA (C30) and 50 wt% HA/PLLA (C50) and a one-side HA-coated PLLA (HAcP) were evaluated. Rectangular specimens were incubated in various acellular aqueous buffer solutions [citrate, Gomori's and phosphate-buffered saline (PBS)] up to 24 weeks. Data for cumulative release of calcium, phosphate and l-lactate release in solutions containing C30 or C50 showed linear patterns. Release data for solutions containing HAcP combined with scanning micrographs, X-ray microanalysis and X-ray diffraction patterns of the specimens in time showed that the plasma-sprayed HA coating on PLLA dissolves significantly, progressively in the first weeks and almost completely within the tested period of 24 weeks in vitro. A precipitate of scaly crystallites (calcium phosphates) was observed at the HA coating-PBS interface. After 24 weeks incubation all materials were still above their initial weight, indicating that swelling still exceeded dissolution. Application of C30, C50 and HAcP as implant materials seems interesting where initial stabilization through bone bonding is needed or where the linear release of constituents is a requirement. HAcP has the advantage that the HA coating acts as a hydrolysis barrier and consequently delays the degradation of PLLA in vitro. 相似文献
995.
996.
OBJECTIVE: To evaluate what nursing home medical directors actually do, what they and other nursing home personnel believe would be desirable to do, and what problems and deficiencies are perceived. DESIGN: Mail survey with follow-up telephone interview when necessary. SETTING: Forty-five nursing facilities in upstate New York. PARTICIPANTS: The medical directors, administrators, and directors of nursing of the 45 facilities. MEASUREMENTS: Inventory of what medical directors reported as to their actual activities and time spent, and of what they, the administrators, and the directors of nursing felt should be their responsibilities and activities under ideal circumstances. RESULTS: For part-time medical directors, self-reported time spent on medical directorship activities averaged 12 hours per month; of all directors, 45% spent 8 hours or less per month. Proportion of time spent on various specific activities varied widely. There was general agreement that substantially more time should be spent, in particular, on evaluating and addressing problems of adequacy and quality of care, communicating with attending physicians about problems, and assisting with inservice training programs. CONCLUSIONS: To fill the role adequately, more time should be spent by many part-time medical directors, which will require greater financial commitment by facilities and reimbursement systems. Efforts need to made to better coordinate the expectations of medical directors and facility staff. 相似文献
997.
The purpose of this study was to determine whether retention of fetal lung liquid is more prevalent in polyalveolar congenital lobar emphysema than in conventional congenital lobar emphysema. Two patients with congenital lobar emphysema were prospectively identified in a 3-year period. Twenty-five such patients were identified in a retrospective study covering 39 years. Medical records were available for 22 patients who had 23 emphysematous lobes. Both babies from the prospective study and six subjects from the retrospective group had respiratory symptoms and underwent chest X-ray in the first day of life. Six of the eight babies with respiratory symptoms and chest imaging in the first day of life had retention of fetal lung liquid in an emphysematous lobe. All six of these lobes were polyalveolar. The lobe in one child was a polyalveolar lobe but without retained fetal lung liquid, and one child exhibited conventional lobar emphysema also without retained fetal lung liquid. One polyalveolar lobe caused no neonatal symptoms and was not imaged until the child was 3 months old. No baby with conventional lobar emphysema was shown to have retained fetal lung liquid. There seems to be a correlation between polyalveolar lobe and onset of respiratory symptoms in the first day of life. Retention of fetal lung liquid within the affected lobe was documented only in cases of polyalveolar lobe. 相似文献
998.
F Jónsson P Madsen LG J?rgensen M Lunding NH Secher 《Canadian Metallurgical Quarterly》1996,158(44):6256-6259
Indices of fluid balance were evaluated during and after aortic surgery in 16 consecutive patients. Thoracic electrical impedance (TI), heart rate (HR), central venous (CVP), pulmonary artery mean (PAMP), pulmonary wedge (PWP) and mean arterial (MAP) pressures as well as fourteen arterial and venous blood gas variables were followed. Consistent with a reduction of TI during the operation, fluid balance was in excess, and it remained elevated on the first postoperative morning. The HR, MAP and PWP remained stable, while CVP and PAMP decreased. Of the determined variables only TI revealed a meaningful correlation to fluid balance (rho = -0.41; p < 0.01). The results indicate that while central venous and pulmonary artery mean pressures gave the impression of a volume deficit, the positive fluid balance was mirrored by thoracic electrical impedance. 相似文献
999.
Good access to health facilities providing good first-level health care remains problematic in many developing countries. It is a hindrance to effective and efficient functioning of the hospital, as outpatient departments become overcrowded with patients from areas without health centres. In many cases the quality of care delivered to these patients is poor because within the district health system the hospital is not the best place for the supply of comprehensive, integrated and continuous care. Eventually, high hospital involvement in first-level care can jeopardize the delivery of adequate referral care for those patients who desperately need the hospital's technology and expertise. This paper provides an account of the way this problem was investigated and managed by the district health management team in the Murewa district in north-east Zimbabwe. The design of a comprehensive 'master plan' or 'coverage plan' is presented as well as the problems and difficulties encountered. The Murewa experience highlights the relevance of a coverage plan for rational and coherent health infrastructure planning at district level. The approach followed by the Murewa team illustrates the use of action research as an integral part of the management of district health systems. 相似文献
1000.