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991.
Parathyroid cysts are a very rare disease entity. Hormone activity is uncommon and they usually present without any clinical symptoms. The differential diagnosis of cystic neck masses should nevertheless include parathyroid cysts as surgical therapy can be very effective. We report the case of a 57-year-old patient presenting to our department with a hormone inactive parathyroid cyst. Final diagnosis was achieved eventually after histological examination of the resected specimen, which is the reason for evaluating the current data for preoperative management of this disease entity in this case report. 相似文献
992.
OBJECTIVE: In patients with prostate cancer, extended pelvic lymph node dissection (ePLND) yields a higher number of lymph node metastases (LNM) than standard pelvic lymph node dissection (PLND) of the obturator fossa only. We describe our laparoscopic technique of extended lymph node dissection and provide the number and locations of positive lymph nodes from our experience. METHODS: In a total of 35 selected patients with clinically localized prostate cancer, laparoscopic ePLND was performed prior to laparoscopic radical prostatectomy. The template included the genitofemoral nerve up to the bifurcation of the common iliac artery and down to the epigastric artery. In the "split and roll" technique the internal and external iliac arteries including the bifurcation and the external iliac vein were completely mobilized. After freeing the obturator nerve, the entire lymph node package was released from the pelvic side wall. RESULTS: Mean operative time was 90min/patient. The complications were two temporary and reversible neurapraxias (ischiatic nerve and obturator nerve), one deep vein thrombosis, and two lymphoceles. One lymphocele healed conservatively; the second was marsupialized laparoscopically. Eleven (31.4%) patients had lymph node metastases; their mean prostate-specific antigen (PSA) level was 20.3+/-7.0 ng/ml (range: 5.2-39.7 ng/ml) and their median Gleason sum in biopsy was 7 (range: 6-8). Mean size of the LNM was 3.1+/-1.0 mm (range: 0.2-8). In 5 of the 11 patients with LNM these were detected exclusively outside the obturator fossa. LNM were in the obturator fossa only in two (one bilateral), around the external iliac artery only in two, around the internal iliac artery only in two, and around the external iliac artery and internal iliac only in one patient. CONCLUSIONS: Laparoscopic ePLND can be combined with laparoscopic radical prostatectomy. Standardization of the technique facilitates surgery to a great extent. e-PLND detects LNM in a significant number of patients. The majority of LNM are outside the obturator fossa. The transperitoneal approach allows a wide exposure and is the most important factor to enable successful ePLND. 相似文献
993.
Staying safe: simple tools for safe surgery 总被引:4,自引:0,他引:4
Karl RC 《Bulletin of the American College of Surgeons》2007,92(4):16-22
994.
Celsior versus custodiol: early postischemic recovery after cardioplegia and ischemia at 5 degrees C
BACKGROUND: The aim of this experimental study was to compare the protective efficacy of the cardioplegic solutions Celsior and Custodiol. Canine hearts were examined with regard to energy metabolism and early postischemic recovery after 8 or 12 hours of ischemia at 5 degrees C. METHODS: Canine hearts were preserved with Celsior or Custodiol (each n = 19). Five hearts of each group were used to determine myocardial content of energy-rich phosphates immediately after preservation and after 8 and 12 hours of ischemia at 5 degrees C; the remainder were reperfused after 8 and 12 hours of ischemia. Control variables during reperfusion were myocardial content of energy-rich phosphates, myocardial K+ uptake, left ventricular dP/dtmax and dP/dtmin, and incidence of arrhythmias in percentage of heart rate. RESULTS: Custodiol-preserved hearts contained more ATP than Celsior-preserved hearts after 8 and 12 hours of ischemia (8 hours p = ns, 12 hours, p < 0.05). During reperfusion after 8 hours of ischemia, dP/dtmax and dP/dtmin showed the same values for both solutions, after 12 hours values were significantly higher in Custodiol-preserved hearts (p < 0.005). The incidence of reperfusion arrhythmias was higher in hearts of the Celsior group (8 hours p < 0.01, 12 hours p = ns). Myocardial K+ uptake during reperfusion after 8 and 12 hours of ischemia was about twice as high in Celsior-preserved compared to Custodiol-preserved hearts (p < 0.005). CONCLUSIONS: In the Langendorff model of the canine heart, cardioplegia with Celsior showed no advantage over cardioplegia with Custodiol. Differences were observed, however, which may be clinically important, especially in the case of long cold-storage times. 相似文献
995.
Maurice Balke Jonas Mueller-Huebenthal Sven Shafizadeh Dennis Liem Juergen Hoeher 《Journal of orthopaedic surgery and research》2010,5(1):11
Aplasia of both cruciate ligaments is a rare congenital disorder. A 28-year-old male presented with pain and the feeling of
instability of his right knee after trauma. The provided MRI and previous arthroscopy reports did not indicate any abnormalities
except cruciate ligament tears. He was referred to us for reconstruction of both cruciate ligaments. The patient again underwent
arthroscopy which revealed a hypoplasia of the medial trochlea and an extremely narrow intercondylar notch. The tibia revealed
a missing anterior cruciate ligament (ACL) footprint and a single bump with a complete coverage with articular cartilage.
There was no room for an ACL graft. A posterior cruciate ligament could not be identified. The procedure was ended since a
ligament reconstruction did not appear reasonable. A significant notch plasty if not a partial resection of the condyles would
have been necessary to implant a ligament graft. It is most likely that this would not lead to good knee stability. If the
surgeon would have retrieved the contralateral hamstrings at the beginning of the planned ligament reconstruction a significant
damage would have occurred to the patient. Even in seemingly clear diagnostic findings the arthroscopic surgeon should take
this rare abdnormality into consideration and be familiar with the respective radiological findings. We refer the abnormal
finding of only one tibial spine to as the "dromedar-sign" as opposed to the two (medial and a lateral) tibial spines in a
normal knee. This may be used as a hint for aplasia of the cruciate ligaments. 相似文献
996.
Potassium Bicarbonate Supplementation Lowers Bone Turnover and Calcium Excretion in Older Men and Women: A Randomized Dose‐Finding Trial 下载免费PDF全文
Bess Dawson‐Hughes Susan S Harris Nancy J Palermo Cheryl H Gilhooly M Kyla Shea Roger A Fielding Lisa Ceglia 《Journal of bone and mineral research》2015,30(11):2103-2111
The acid load accompanying modern diets may have adverse effects on bone and muscle metabolism. Treatment with alkaline salts of potassium can neutralize the acid load, but the optimal amount of alkali is not established. Our objective was to determine the effectiveness of two doses of potassium bicarbonate (KHCO3) compared with placebo on biochemical markers of bone turnover, and calcium and nitrogen (N) excretion. In this double‐blind, randomized, placebo‐controlled study, 244 men and women age 50 years and older were randomized to placebo or 1 mmol/kg or 1.5 mmol/kg of KHCO3 daily for 3 months; 233 completed the study. The primary outcomes were changes in 24‐hour urinary N‐telopeptide (NTX) and N; changes in these measures were compared across the treatment groups. Exploratory outcomes included 24‐hour urinary calcium excretion, serum amino‐terminal propeptide of type I procollagen (P1NP), and muscle strength and function assessments. The median administered doses in the low‐dose and high‐dose groups were 81 mmol/day and 122 mmol/day, respectively. When compared with placebo, urinary NTX declined significantly in the low‐dose group (p = 0.012, after adjustment for baseline NTX, gender, and change in urine creatinine) and serum P1NP declined significantly in the low‐dose group (p = 0.004, adjusted for baseline P1NP and gender). Urinary calcium declined significantly in both KHCO3 groups versus placebo (p < 0.001, adjusted for baseline urinary calcium, gender, and changes in urine creatinine and calcium intake). There was no significant effect of either dose of KHCO3 on urinary N excretion or on the physical strength and function measures. KHCO3 has favorable effects on bone turnover and calcium excretion and the lower dose appears to be the more effective dose. Long‐term trials to assess the effect of alkali on bone mass and fracture risk are needed. © 2015 American Society for Bone and Mineral Research. 相似文献
997.
998.
Effects of trypsinization and mineralization on intrasynovial tendon allograft healing to bone 下载免费PDF全文
Jin Qu Nick A. van Alphen Andrew R. Thoreson Qingshan Chen Kai‐Nan An Peter C. Amadio Thomas M. Schmid Chunfeng Zhao 《Journal of orthopaedic research》2015,33(4):468-474
The purpose of the current study was to develop a novel technology to enhance tendon‐to‐bone interface healing by trypsinizing and mineralizing (TM) an intrasynovial tendon allograft in a rabbit bone tunnel model. Eight rabbit flexor digitorum profundus (FDP) tendons were used to optimize the trypsinization process. An additional 24 FDP tendons were stratified into control and TM groups; in each group, 4 tendons were used for in vitro evaluation of TM and 8 were transplanted into proximal tibial bone tunnels in rabbits. The samples were evaluated histologically and with mechanical testing at postoperative week 8. Maximum failure strength and linear stiffness were not significantly different between the control and TM tendons. A thin fibrous band of scar tissue formed at the graft‐to‐bone interface in the control group. However, only the TM group showed obvious new bone formation inside the tendon graft and a visible fibrocartilage layer at the bone tunnel entrance. This study is the first to explore effects of TM on the intrasynovial allograft healing to a bone tunnel. TM showed beneficial effects on chondrogenesis, osteogenesis, and integration of the intrasynovial tendon graft, but mechanical strength was the same as the control tendons in this short‐term in vivo study. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:468–474, 2015. 相似文献
999.
Alterations in intervertebral disc composition,matrix homeostasis and biomechanical behavior in the UCD‐T2DM rat model of type 2 diabetes 下载免费PDF全文
Aaron J. Fields Britta Berg‐Johansen Lionel N. Metz Stephanie Miller Brandan La Ellen C. Liebenberg Dezba G. Coughlin James L. Graham Kimber L. Stanhope Peter J. Havel Jeffrey C. Lotz 《Journal of orthopaedic research》2015,33(5):738-746
Type 2 diabetes (T2D) adversely affects many tissues, and the greater incidence of discogenic low back pain among diabetic patients suggests that the intervertebral disc is affected too. Using a rat model of polygenic obese T2D, we demonstrate that diabetes compromises several aspects of disc composition, matrix homeostasis, and biomechanical behavior. Coccygeal motion segments were harvested from 6‐month‐old lean Sprague‐Dawley rats, obese Sprague‐Dawley rats, and diabetic obese UCD‐T2DM rats (diabetic for 69 ± 7 days). Findings indicated that diabetes but not obesity reduced disc glycosaminoglycan and water contents, and these degenerative changes correlated with increased vertebral endplate thickness and decreased endplate porosity, and with higher levels of the advanced glycation end‐product (AGE) pentosidine. Consistent with their diminished glycosaminoglycan and water contents and their higher AGE levels, discs from diabetic rats were stiffer and exhibited less creep when compressed. At the matrix level, elevated expression of hypoxia‐inducible genes and catabolic markers in the discs from diabetic rats coincided with increased oxidative stress and greater interactions between AGEs and one of their receptors (RAGE). Taken together, these findings indicate that endplate sclerosis, increased oxidative stress, and AGE/RAGE‐mediated interactions could be important factors for explaining the greater incidence of disc pathology in T2D. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:738–746, 2015. 相似文献
1000.
Collagen gel contraction as a measure of fibroblast function in an animal model of subsynovial connective tissue fibrosis 下载免费PDF全文
Tai‐Hua Yang Andrew R. Thoreson Anne Gingery Dirk R. Larson Sandra M. Passe Kai‐Nan An Chunfeng Zhao Peter C. Amadio 《Journal of orthopaedic research》2015,33(5):668-674
Carpal tunnel syndrome (CTS) is a peripheral neuropathy characterized by non‐inflammatory fibrosis of the subsynovial connective tissues (SSCT). A rabbit model of CTS was developed to test the hypothesis that SSCT fibrosis causes the neuropathy. We used a cell‐seeded collagen‐gel contraction model to characterize the fibrosis in this model in terms of cellular mechanics, specifically to compare the ability of SSCT cells from the rabbit model and normal rabbits to contract the gel, and to assess the effect of transforming growth factor‐β1,which is upregulated in CTS, on these cells. SSCT fibrosis was induced in six retired breeder female rabbits which were sacrificed at 6 weeks (N = 3) and 12 weeks (n = 3). An additional two rabbits served as controls. SSCT was harvested according to a standard protocol. Gels seeded with SSCT cells from rabbits sacrificed at 6 weeks had significantly higher tensile strength (p < 0.001) and Young's modulus (p < 0.001) than gels seeded with cells from rabbits sacrificed at 12 weeks or control animals. TGF‐β1 significantly increased the decay time constant (p < 0.001), tensile strength (p < 0.001), and Young's modulus (p < 0.001) regardless of the cell source. This model may be useful in screening therapeutic agents that may block SSCT fibrosis, identifying possible candidates for CTS treatment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:668–674, 2015. 相似文献