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T Koperna S Vogl U Satzinger F Schulz 《Canadian Metallurgical Quarterly》1997,21(8):850-4; discussion 854-5
Nonparasitic cysts of the liver (NPHC) are highly variable in respect to appearance and therapeutic approach. The treatment of these cysts varies according to the nature and appearance of the disease. Based on the variable nature of disease and the various therapeutic options, all of which were attempted in our patients, the most suitable mode of treatment for different forms of NPHC are discussed. Ninety-one patients with NPHC who had been treated surgically from 1977 through 1995 were examined retrospectively. Asymptomatic peripheral cysts measuring up to 10 cm do not require further treatment. Computed tomography (CT)-guided aspiration (n = 9) should be regarded as a palliative measure. Within a short period, CT-guided aspiration led to recurrence of symptoms in seven of our patients. Standard treatment of NPHC is fenestration with widest possible excision of the cystic wall, which can be performed laparoscopically (n = 10) or by the conventional surgical mode (n = 54). One patient was initially operated by the laparoscopic technique but developed bleeding, which necessitated conversion to the open mode. Three patients underwent synchronous laparoscopic cholecystectomy. Recurrence rates were similar: 11% in the laparoscopically treated group and 13% in the group that underwent conventional open surgery. Conventional surgical treatment was always successful in cases of solitary cysts. However, in cases of multiple cysts measuring more than 5 cm, conventional surgery was followed by recurrence of symptoms in 26% of patients (7/27), who then had to undergo a second operation. Partial resection of the liver (n = 9) was successfully performed in cases of polycystic disease (n = 5) with concomitant enlargement of the organ as well as in cases of large solitary cysts of the left lobe of the liver (n = 4). In patients in whom we found that the cysts communicated with the ductal system (n = 3), we performed a cystojejunostomy to drain the bile. The complication rate was low. In addition to frequent postoperative ascites, which necessitated no further intervention, we observed infectious complications in four patients. Twenty patients (22%) expired during a mean follow-up period of 6.2 years. Interestingly, deaths were frequently associated with malignancy (11/20). After fenestration of multiple cysts measuring > 5 cm, the patients are at high risk for recurrence. Hence partial resection of the liver is an excellent therapeutic alternative in selected patients with polycystic disease and massive enlargement of the organ in whom the disease could not be controlled by simple fenestration. The results of this study show that laparoscopic fenestration should replace the conventional surgical technique as the gold standard in cases of NPHC because the laparoscopic technique is less stressful for the patient and is associated with a rate of success similar to that of the conventional technique. 相似文献
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We have studied the function of partial orthotopic liver transplantation in the rat by evaluating prothrombin time (PT), liver blood flow, basal and glucose-stimulated insulin secretion and glucose tolerance, and the reticuloendothelial function (RES) in hepatectomized rats subjected to partial liver transplantation. A graft corresponding to 68% of a normal liver was transplanted to totally hepatectomized rats. Comparison was made between control rats and rats subjected to 32% liver resection. PT was not significantly different in the transplanted group compared with liver-resected and control rats. Laser Doppler flowmetry showed that at 28 days after surgery, blood flow had increased in the transplanted livers. Furthermore, on the third day after transplantation, basal plasma insulin was increased and the plasma insulin response to glucose was exaggerated, suggesting reduced insulin action and impaired insulin degradation. Finally, uptake of radioactive-labeled E. coli bacteria, as a measure of RES function, was not compromised in transplanted animals. Based on these results, we conclude that reduced-size liver transplant in out-bred rats results in fast normalization of liver function after surgery although, immediately after surgery, glucose intolerance is seen. 相似文献
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OBJECTIVE: To examine the association between sexual abuse in childhood and adult depression in women. DESIGN: Two stage, case detection and case identification design, using the 30-item general health questionnaire and the Beck depression inventory for screening and the affective items relating to current functioning on the schizophrenia and affective disorders schedule to identify depressed cases. Details of sexual abuse in childhood were elicited retrospectively by semistructured interview, and social problems by the social problems questionnaire. SETTING: Three general practices, in middle class suburban, deprived inner city, and rural areas. SUBJECTS: 1189 women were screened and 237 subsequently interviewed; 132 were depressed. RESULTS: 49 (37%) of the depressed interviews and 24 (23%) of the non-depressed interviews reported experience of sexual abuse when they were aged under 16 years. A positive association existed between the more severe abuse and depression--all those who had experienced penetration were depressed as adults. A relation was also found between sexual abuse in childhood and sexual problems, housing problems, and problems with their children at school. CONCLUSION: A positive association between child sexual abuse and depression was confirmed, but this was confined to more severe abuse (penetration or attempted penetration). 相似文献
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The implementation of Medicare's prospective payment system in acute care has coincided with a steady increase in medically unstable admissions to our freestanding rehabilitation facility. We investigated the consequences of these admissions by collecting medical information regarding transfers beginning in 1983. Patients requiring transfer back to the acute setting within 1 day of admission were considered medically unstable and their charts were reviewed. The number of patients requiring transfer back within 1 day increased from 1.5% of all first admissions to 3.1% in 1988 (Mantel - Haenszel chi 2 = 8.03, (df = 1), p < .01), but the increase among Medicare patients alone was not significant. This progressive increase was most pronounced in the cerebrovascular accident and spinal cord injury populations. Beginning in 1988, an intensified preadmission evaluation program was implemented, resulting in a significant decline in unstable patient transfers from hospitals where our consultants were on staff. Physiatric consultations at referral institutions decreased the number of unstable patients at admission. 相似文献
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The purpose of this study was to identify family physicians' firearm safety counseling beliefs and behaviors. A survey was mailed to a random sample of 600 members of the American Academy of Family Physicians. A three wave mailing technique was used to maximize the response rate and yielded 271 usable surveys (55% response rate). Outcome measures included training experience in firearm safety counseling, the prevalence of firearm safety counseling by family physicians, and their perceptions regarding such counseling. The majority (78%) of family physicians lacked formal training on how to counsel patients about firearm safety and 49% believed more time should be spent in residency programs on firearm safety counseling. The majority (84%) of respondents never or rarely counseled patients on firearm safety and 50% believed firearm safety counseling should be a low priority in their delivery of primary care. The majority of respondents did not regularly counsel patients about firearm safety, did not believe firearm safety counseling should be a priority, and did not believe firearm safety counseling would be effective in reducing firearm-related trauma. 相似文献
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Cis-1,4-polybutadiene (PB) in a 0.5% solution of a solvent mixture of dichloromethane and 1,2-dibromoethane or tetrahydrofuran was quantitatively brominated with elemental bromine at 0°C under careful exclusion of oxygen to head-to-head poly(vinyl bromide). Partially brominated PB has a structure of random or block sequences of butadiene units in the polymer depending on the bromination solvent but shows no stereospecificity in the CHBrCHBr-dyads. Partially brominated PB with block structure showed a microphase-separated morphology over a wide range of composition. Microphase separation is less pronounced for the more random structure of butadiene units. I.r and 13C n.m.r. spectroscopy of the partially brominated PB was used to follow the progress of the bromination. 相似文献
10.
Many new speciality polymers have been developed in the last few years. In this paper polymeric stabilizers (antioxidants, flame retardants and ultraviolet stabilizers) will be discussed. Polymeric antioxidants of the hindered-phenol type, copolymers of 2,6-ditertiarybutyl-4-vinyl(or isopropenyl)phenol with styrene, methyl methacrylate, or more importantly butadiene or isoprene have been prepared; hydrogenation of the latter copolymers gave copolymers of the two polymerizable phenolic antioxidants with ethylene or ethylene/propylene. The polymeric antioxidants have been blended with diene polymers and selected polyolefins and have improved the long-term oxidative stability of these polymers. Polymeric flame retardants have been prepared by copolymerizing styrene and/or acrylonitrile with acrylates and methacrylates of aliphatic bromine-containing alcohols or bromine-containing phenols. Polymers with polymer-bound flame retardants have a higher limiting oxygen index compared with the original polymer. A new class of polymerizable ultraviolet stabilizers has also been developed; these stabilizers are styryl, α-methylstyryl, acryloyl and methacryloyl derivatives of 2(2-hydroxyphenyl)2H-benzotriazoles. These monomers have been copolymerized with styrene, acrylates and methacrylates. 2(2-Hydroxyphenyl)2H-benzotriazoles substituted in the 4 position of the benzotriazole ring with hydroxyl, acetoxy or carboxyl groups suitable for incorporation into polyesters, polycarbonates, polyamides and epoxy resins have also been synthesized. All 2(2-hydroxyphenyl)2H-benzotriazole ultraviolet absorbers and the polymers into which they are incorporated have high light absorbency with γmax between 330 and 350 nm and extinction coefficients in some cases as high as 4.5 × 104 1 mol?1 cm?1. 相似文献