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21.
Ohrvall U Eriksson B Juhlin C Karacagil S Rastad J Hellman P Akerström G 《World journal of surgery》2000,24(11):1402-1408
With adequate medical management the midgut carcinoid tumor generally is an indolent malignancy associated with substantial
life expectancy and appreciable life quality, even in the presence of liver metastases and significant tumor burden. Abdominal
complications may occur in this entity of carcinoids owing to entrapment of intestines and encasement of mesenteric vessels
by mesenteric metastases and associated marked mesenteric fibrosis. This may be the cause of abdominal pain, disabling diarrhea,
weight loss to the extent of malnutrition, and eventually the risk of death with acute or chronic intestinal obstruction or
intestinal gangrene. Operative removal of the mesentericointestinal lesion is often indicated to prevent or treat these complications
but may be technically difficult when mesenteric metastases extend in the vicinity of major vessels in the mesenteric root.
At laparotomy 56 patients with advanced midgut carcinoids underwent removal of the mesenteric tumor with a method for preserving
the mesenteric vessels. This was feasible by mobilizing and releasing the right colon and mesenteric root from posterior adhesions,
identifying the mesenteric artery below the pancreas, and free-dissecting this artery on the tumor capsule in the mobilized
mesentery. Dissection was successful even with tumors initially judged inoperable unless tumor growth completely surrounded
the mesenteric vessels or extended retroperitoneally. One patient was subjected to distal intestinal artery bypass. Symptom
relief was been substantial and often of long duration after mesenteric tumor removal in patients who prior to surgery often
had threatening intestinal ischemia. Patients with advanced midgut carcinoids may benefit markedly from dissectional removal
of mesenteric tumors, which (conceivably better than conventional wedge resection) preserves the length of the remaining intestine. 相似文献
22.
STUDY DESIGN: An in vitro biomechanical analysis of the segmental motion behavior of the same segments in polysegmental (five segments), bisegmental, and monosegmental specimens using sheep lumbosacral spines. OBJECTIVES: To investigate the effect of specimen length on monosegmental motion behavior. These data may be helpful in planning in vitro tests and in comparing results of studies using specimens of different lengths. SUMMARY OF BACKGROUND DATA: The length of spinal specimens used for in vitro stability tests varies greatly, depending on the purpose of the study. Some investigators prefer testing specimens with one adjacent segment on either end of the region of interest. Others favor specimens as short as possible. METHODS: In a first step, seven sheep spine specimens, L3-S1 (note that sheep spines normally have seven lumbar vertebrae), each were tested without preload in a spine-loading apparatus. Alternating sequences of pure lateral bending, flexion/extension, and axial rotation moments (+/-3.75 Nm) were applied continuously. The motion in each single segment was measured simultaneously. Then, these polysegmental specimens were cut into two bisegmental specimens, L3-L5 and L6-S1, and tested in the same way. Finally, another vertebra was removed to obtain two monosegmental specimens, L3-L4 and L7-S1, and to test them as described. RESULTS: In general, the range of motion at L3-L4 and L7-S1 was smaller when tested in polysegmental than in monosegmental specimens. In polysegmental specimens (five segments), the range of motion at L3-L4 and L7-S1 was approximately 80% (range, 70.6-92.5%) and in bisegmental specimens approximately 95% (range, 66.7-100%) of their range of motion measured in monosegmental specimens. Neutral zone and coupled motions showed the inverse behavior. Significant differences were found. However, they were not consistent with either the loading direction or with the specimen length. CONCLUSIONS: For comparison of results, the specimen length should be kept constant within one experiment. Segmental motion behavior of specimens with different lengths should be compared only qualitatively. 相似文献
23.
The cell activity of human bone derived cell cultures was studied after mechanical stimulation by cyclic strain at a magnitude occurring in physiologically loaded bone tissue. Monolayers of subconfluently grown human bone derived cells were stretched in rectangular silicone dishes with cyclic uniaxial movement along their longitudinal axes. Strain was applied over two days for 30 min per day with a frequency of 1 Hz and a strain magnitude of 1000 mustrain. Cyclic stretching of the cells resulted in an increased proliferation (10-48%) and carboxyterminal collagen type I propeptide release (7-49%) of human cancellous bone derived osteoblasts while alkaline phosphatase activity and osteocalcin release were significantly reduced by 9-25% and 5-32% respectively. These results demonstrate that cyclic strain at physiologic magnitude leads to an increase of osteoblast activities related to matrix production while those activities which are characteristic for the differentiated osteoblast and relevant for matrix mineralization are decreased. 相似文献
24.
W. Greiner C. Claes J. J. V. Busschbach J.-M. Graf von der Schulenburg 《The European journal of health economics》2005,6(2):124-130
The aim of this survey study was to derive the societal values of the general public for the EuroQol EQ-5D. Using the same protocol as previously used in the United Kingdom, we compared the German values with the British. In face-to-face interviews a sample of 339 individuals in northern Germany valued 15 different health states from a sample of 36 states. Values were derived using the York MVH protocol for time trade-off (TTO) and a visual analogue scale (VAS). Values for all 243 health states of the EQ-5D were estimated by a regression model. The VAS values revealed close a resemblance to the British VAS results. German TTO values were higher than the British. This was especially the case for the worse health states. The results suggest that the TTO values are more related to national variables than values derived by VAS. The use of the TTO values of this investigation makes it possible to anticipate these cultural differences in studies carried out in Germany. 相似文献
25.
26.
Ylva Dahlin Redfors Sara Olaison Jan Karlsson Johan Hellgren Claes Möller 《International journal of audiology》2015,54(2):63-69
Objectives: The aims of the study were to assess health-related quality of life and hearing-related disability in subjects with otosclerosis 30 years after surgery. Design: An observational study was performed. Medical records were reviewed, a clinical examination as well as audiometric assessments were performed. Generic health-related quality of life was assessed by the SF-36v2 and hearing disability by a shortened version of SSQ (speech spatial and qualities of hearing scale). Study sample: Sixty-five individuals, who had undergone stapedectomy in 1977-79 at a tertiary referral center. Results: Generic health-related quality of life according to SF-36 subscale scores was comparable to that of an age- and sex-matched reference population. The SF-36 mental component summary score (MCS) was, however, significantly better than that of the reference population. The mental and physical summary component scores correlated significantly to hearing disability measured by the SSQ but not to hearing impairment. Hearing disability was displayed in all SSQ sub-scores, especially in more complex listening situations and in the localization of sounds. Conclusions: This study shows that individuals with otosclerosis, 30 years after surgery, have a good generic health-related quality of life, despite moderate to severe hearing loss and significant hearing disabilities. 相似文献
27.
Claes H. Dohlman 《Ophthalmology》1978,85(12):1277-1281
28.
G. Van Pottelbergh L. Hoste J. Degryse H. Pottel K. Claes N. Demoulin M. Jadoul B. Bammens P. Wallemacq 《Clinical biochemistry》2013,46(1-2):31-36
ObjectivesMeasuring the exact glomerular filtration rate (GFR) is difficult. Iohexol can be used instead of inulin or labeled EDTA or DTPA. In recent years, different studies have validated GFR-estimating equations in adults. Validation of these estimations in adolescents and elderly is lacking. With this study, we aim to develop a simplified (only 1–3 blood collections) iohexol protocol to measure the true GFR for patients of all ages and try to develop GFR-estimating equations for adolescents and the elderly.Design and settingParticipants of different ages will be recruited: 50 adolescent (14–18 years) and 30 adults (20–65 years), 60 elderly (65–80 years) and 60 very elderly (80 + years old) stratified based on their GFR. Biometric data, serum creatinine and cystatin C will be measured. After injecting 5 mL iohexol, 9 blood samples will be taken between 20 and 360 min. First, the GFR will be calculated by using the double exponential decay method and different GFRs based on 1–3 blood samples, which will be compared with the GFR of the abovementioned 9 samples. Second, the GFR will be calculated by using new and existing equations and compared to the true GFR.DiscussionThe availability of a reliable GFR measurement is important in situations such as screening patients for kidney donation or when taking potentially nephrotoxic treatments. This study will allow us to develop a simplified protocol for measuring the true GFR in all ages and will allow us to validate existing equations and develop new eGFR equations for adolescents and the elderly. 相似文献
29.
Stefan Recknagel Ronny Bindl Julian Kurz Tim Wehner Christian Ehrnthaller Markus Werner Knöferl Florian Gebhard Markus Huber‐Lang Lutz Claes Anita Ignatius 《Journal of orthopaedic research》2011,29(5):734-739
In poly‐traumatic patients a blunt chest trauma is an important trigger of the posttraumatic systemic inflammatory response. There is clinical evidence that fracture healing is delayed in such patients, however, experimental data are lacking. Therefore, we investigated the influence of a thoracic trauma on fracture healing in a rat model. Male Wistar rats received either a blunt chest trauma combined with a femur osteotomy or an isolated osteotomy. A more rigid or a more flexible external fixator was used for fracture stabilization to analyze whether the thoracic trauma influences regular healing and mechanically induced delayed bone healing differently. The blunt chest trauma induced a significant increase of IL‐6 serum levels after 6 and 24 h, suggesting the induction of a systemic inflammation, whereas the isolated fracture had no effect. Under a more rigid fixation the thoracic trauma considerably impaired fracture healing after 35 days, reflected by a significantly reduced flexural rigidity (three‐point‐bending test), as well as a significantly diminished callus volume, moment of inertia, and relative bone surface (µCT analysis). In confirming the clinical evidence, this study reports for the first time that a blunt chest trauma considerably impaired bone healing, possibly via the interaction of the induced systemic inflammation with local inflammatory processes. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:734–739, 2011 相似文献
30.
Nedim Selimovic Bert Andersson Claes‐Håkan Bergh Gunnar Mårtensson Folke Nilsson Odd Bech‐Hanssen Bengt Rundqvist 《Transplant international》2008,21(4):314-319
Lung transplantation (LTx) is a therapeutic option for patients with end-stage lung disease. However, the mortality rate of patients on the waiting list is high. The purpose of this study was to examine the prognostic value of cardio-pulmonary hemodynamics for death in patients awaiting LTx. Retrospectively, 177 patients with advanced lung disease accepted for LTx at Sahlgrenska University Hospital from January 1990 through December 2003 were studied. Patient demographics, pulmonary function tests, gas exchange and hemodynamic variables were included in the analysis. Death while awaiting LTx was the primary endpoint for all analyses. Mean age was 49 +/- 9 years. Main diagnoses were alpha 1 antitrypsin deficiency (n = 56), chronic obstructive pulmonary disease (n = 61), cystic fibrosis (n = 14) and interstitial lung disease (n = 46). Thirty patients died (17%). LTx was performed in 143 cases. By univariate analyses, forced vital capacity (FVC) % of predicted, pulmonary vascular resistance (PVR) and diagnosis were associated with risk for death. In multivariate analysis PVR (HR, 1.22; 95% CI, 1.06-1.41; P = 0.006) and FVC% of predicted (HR, 0.97; 95% CI, 0.94-0.99; P = 0.01) were independently associated with death. Patients with increased PVR and a lower FVC % of predicted awaiting LTx should be considered for a higher organ allocation priority. Assessment of pulmonary hemodynamics needs to be considered during evaluation for LTx. 相似文献