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991.
Purpose The purpose of this study was to examine the effects of nicardipine-induced hypotension on cerebrovascular CO2 reactivity in patients with diabetes mellitus under sevoflurane anesthesia.
Methods Nineteen diabetic patients, and 11 nondiabetic patients (serving as controls), undergoing elective orthopedic, cardiovascular,
or thoracic surgery were included in the study. The diabetic patients were divided into three groups according to the antidiabetic
therapy they were receiving, i.e., diet therapy (n = 6), oral antidiabetic drugs (n = 7), and insulin (n = 6). Anesthesia was maintained with 1.0 minimum alveolar concentration of sevoflurane. Absolute and relative cerebrovascular
CO2 reactivity was calculated using a 2.5-MHz pulsed transcranial Doppler (TCD) probe for the continuous measurement of mean
blood flow velocity in the middle cerebral artery (Vmca). The cerebrovascular CO2 reactivity was measured both at baseline and during hypotension by increasing the ventilatory frequency by 4 to 7 breaths·min−1. Nicardipine was used to induce hypotension.
Results We found that values for the Bispectral index (BSI), baseline mean blood pressure, endtidal CO2 (PetCO
2), and Vmca were essentially identical in all patients, irrespective of the type of antidiabetic treatment being taken. Values
for absolute and relative CO2 reactivity in insulin-dependent patients, at both baseline blood pressure and during hypotension, were lower than those in
patients in the antidiabetic drug, diet, and control groups (during hypotension, absolute CO2 reactivity: diet group: 3.2 ± 0.9; oral antidiabetic drug group: 3.2 ± 0.7; insulin group: 1.5 ± 0.6; control group: 3.4
± 0.8 cm·s−1·mmHg−1, [P < 0.05 insulin group vs the other groups]; relative CO2 reactivity: diet group, 6.3 ± 1.0; oral antidiabetic drug group, 6.5 ± 0.8; insulin group, 3.5 ± 0.8; control group, 6.5
± 0.7%·mmHg−1, [P < 0.05 insulin group vs the other groups].
Conclusion We concluded that cerebrovascular CO2 reactivity in insulin-dependent patients is impaired during nicardipine-induced hypotension under sevoflurane anesthesia. 相似文献
992.
Kimura N Yamaguchi A Noguchi K Adachi K Adachi H Ino T 《General thoracic and cardiovascular surgery》2007,55(5):212-216
A 59-year-old man with a long history of hypertension and diabetes was admitted to our hospital with acute type B aortic dissection
14 days after the sudden onset of back pain. The dissecting descending thoracic aorta was enlarged to 5.2 cm in diameter,
and laboratory tests showed an elevated white blood cell count (15 530/mm3) and an increased C-reactive protein level (19.2 mg/dl). Computed tomography performed 2 days after admission revealed rapid
growth of the aortic dissection. Blood cultures obtained upon admission were positive for Salmonella. Impending rupture of the aortic dissection complicated by Salmonella infection was strongly suspected, and the patient underwent emergency surgery consisting of debridement and prosthetic graft
placement covered by an omental flap. In this case, it is believed that insidious Salmonella aortitis caused acute type B aortic dissection. 相似文献
993.
Dislodged percutaneous endoscopic gastrostomy (PEG) tubes occur commonly and may require urgent surgical intervention in a
susceptible patient population. Natural orifice translumenal endoscopic surgery (NOTES) may facilitate PEG rescue and avoid
the morbidity associated with contemporary surgical techniques. We report a case of a dislodged PEG tube in the early post-operative
period with evidence of incomplete gastrocutaneous tract formation and intra-abdominal leakage. Bedside transgastric NOTES
exploration facilitated peritoneoscopy, evacuation of intra-abdominal fluid, and re-establishment of the PEG tube through
the original gastrotomy tract. Tube feeds were resumed and postoperative contrast fluoroscopy demonstrated no intra-abdominal
leakage from the replaced PEG tube. No postoperative complications related to the NOTES procedure were noted at 30 days of
follow-up. PEG rescue represents a unique, practical, and empowering application of the burgeoning experience of NOTES.
Electronic Supplementary Material The online version of this article (doi: ) contains supplementary material, which is available to authorized users 相似文献
994.
H. K. Genant P. D. Delmas P. Chen Y. Jiang E. F. Eriksen G. P. Dalsky R. Marcus J. San Martin 《Osteoporosis international》2007,18(1):69-76
Introduction Bone microarchitecture, a component of bone strength, is generally measured on transiliac bone biopsy samples. The objective
of this study was to determine whether assessment of four grades of vertebral fracture severity could serve as a noninvasive
surrogate marker for trabecular bone volume and microarchitecture.
Methods Baseline vertebral fracture severity was determined by semiquantitative assessment of spine radiographs from 190 postmenopausal
women with osteoporosis. Bone-structure indices were obtained by 2D histomorphometry and 3D microcomputed tomography (CT)
analyses. Significance of differences was determined after adjusting for age, height, and lumbar spine bone mineral density.
Results There were significant (P < 0.05) trends in decreasing bone volume, trabecular number, and connectivity, and increasing trabecular
separation with greater vertebral fracture severity. Histomorphometric bone volume was 25 and 36% lower (P < 0.05) in women
with moderate and severe fractures than in women with no fractures, respectively. Compared with women without fractures, women
with mild, moderate, and severe fractures had lower (P < 0.05) microCT bone volume (23, 30, and 51%, respectively).
Conclusions Microarchitectural deterioration was progressively worse in women with increasing severity of vertebral fractures. We conclude
that assessment of vertebral fracture severity is an important clinical tool to evaluate the severity of postmenopausal osteoporosis. 相似文献
995.
Effect of early and late antibiotic treatment in experimental acute pancreatitis in rats 总被引:1,自引:0,他引:1
Michael Schwarz Bertram Poch Rainer Isenmann Dietrich Kriese Eva Rozdzinski Hans G. Beger Frank Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(3):365-370
Background The clinical course in acute necrotizing pancreatitis is mainly determined by bacterial infection of pancreatic and peripancreatic
necrosis. The effect of two antibiotic regimens for early and late treatment was investigated in the taurocholate model of
necrotizing pancreatitis in the rat.
Materials and methods Seventy male Wistar rats were divided into five pancreatitis groups (12 animals each) and a sham-operated group (10 animals).
Pancreatitis was induced by intraductal infusion of 3% taurocholate under sterile conditions. Animals received two different
antibiotic regimes (20 mg/kg imipenem or 20 mg/kg ciprofloxacin plus 20 mg/kg metronidazole) early at 2, 12, 20, and 28 h
after induction of pancreatitis or late at 16 and 24 h after induction of pancreatitis or no antibiotics (control). Animals
were examined after 30 h for pancreatic and extrapancreatic infection.
Results Early and late antibiotic treatment with both regimes could significantly reduce pancreatic infection from 58 to 8–25%. However,
extrapancreatic infection was only reduced by early antibiotic therapy. While quinolones also reduced bacterial counts in
small and large bowel, imipenem did not.
Conclusions In our animal model of necrotizing pancreatitis, early and late treatment with ciprofloxacin/metronidazole and imipenem reduce
bacterial infection of the pancreas. Extrapancreatic infection, however, is reduced significantly only by early antibiotic
treatment. The effectivity of early antibiotic treatment in the clinical setting should be subject to further investigation
with improved study design and sufficient patient numbers. 相似文献
996.
Repair of an Abdominal Aortic Aneurysm with a Remarkably Dilated Meandering Artery: Report of a Case
Sakamoto S Yamauchi S Yamashita H Imura H Maruyama Y Ochi M Shimizu K 《Surgery today》2007,37(2):133-136
A 73-year-old man on dialysis for chronic renal dysfunction was referred to our hospital for surgical treatment of an abdominal
aortic aneurysm (AAA). Preoperative angiography showed a remarkably developed meandering artery branching from the inferior
mesenteric artery (IMA). The superior mesenteric and celiac arteries were occluded at the origin, and all blood flow to the
abdominal organs was apparently supplied by collateral circulation from the IMA. Considering the risk of mesenteric ischemia
after aortic clamping in conjunction during surgery, we used a perfusion catheter with a 12-F balloon to create a shunt to
the IMA from the subclavian artery. The operation was successful and the patient recovered uneventfully. We describe this
surgical procedure for its effectiveness in preventing postoperative mesenteric ischemia in a rare case of an AAA with complex
branching lesions. 相似文献
997.
David Yu Greenblatt Max Cayo Li Ning Renata Jaskula-Sztul Megan Haymart Muthusamy Kunnimalaiyaan Herbert Chen 《Journal of gastrointestinal surgery》2007,11(11):1515-1520
Carcinoid cancers arise from the neuroendocrine cell system of the gastrointestinal tract, lungs, and other organs. Hepatic
metastases are common, and patients often suffer from endocrinopathies secondary to tumor secretion of various hormones and
peptides. As complete surgical resection is often not possible because of widespread disease, new therapeutic and palliative
treatments are needed. In this study, we characterized the effects of suberoyl bishydroxamic acid (SBHA), a histone deacetylase
inhibitor, on the growth and neuroendocrine phenotype of carcinoid cancer cells. SBHA treatment of human gastrointestinal
and pulmonary carcinoid cancer cells resulted in a dose-dependent inhibition of cell proliferation. Western blot analysis
showed a decrease in cyclin D1 and an increase in p21 and p27, indicating that the mechanism of this growth inhibition is
cell cycle arrest. Furthermore, SBHA treatment suppressed two neuroendocrine tumor markers, chromogranin A and achaete-scute
complex-like 1. These changes in the growth and neuroendocrine phenotype of carcinoid cells were associated with activation
of the Notch1 signaling cascade. We conclude that SBHA shows promise as a potential anticancer agent for the treatment of
patients with advanced carcinoid tumor disease.
This paper was presented at the 48th Annual Meeting of the Society for Surgery of the Alimentary Tract, May 19–23, 2007, Washington,
DC, USA. 相似文献
998.
Koji Watanabe Hiroyuki Tsuchiya Keisuke Sakurakichi Teruhisa Yamashiro Hidenori Matsubara Katsuro Tomita 《Journal of orthopaedic science》2007,12(5):471-475
Background In this study, we addressed two questions on the treatment for Ollier's disease: (1) how much callus formation occurs when
an osteotomy is performed intralesionally and (2) how is the stability of the wires and half-pins that are inserted intralesionally.
Methods Four children with Ollier's disease underwent treatment of 12 lower limb segments using distraction osteogenesis until completion
of their growth. All osteotomies were performed at the centers of the deformities, resulting in a total of seven osteotomies
performed intralesionally.
Results Full correction of the deformity and full restoration of length were achieved in all cases, but a residual limb-length discrepancy
of <10 mm remained. The mean external fixation index in the intralesional distraction osteogenesis group was 39.7 days/cm
versus 30.8 days/cm in the extralesional distraction osteogenesis group. Conversion from abnormal cartilage to normal regenerate
bone was seen in only one segment. Although approximately two-thirds of the wires and half-pins were inserted intralesionally,
in all but one case (in which an iatrogenic fracture occurred) the wires and half-pins were well stabilized throughout the
external fixation period.
Conclusions Although deformity and limb-length discrepancies due to Ollier's disease were successfully resolved by distraction osteogenesis,
enchondroma may arise in distracted calluses when osteotomized intralesionally. However, the stability of the external fixator
was sufficient to lengthen limbs and correct deformities even when wires and half-pins were inserted intralesionally. 相似文献
999.
Henry Ahn Payam Mousavi Lee Chin Sandra Roth Joel Finkelstein Alex Vitken Cari Whyne 《European spine journal》2007,16(8):1171-1178
A biomechanical study comparing simulated lytic vertebral metastases treated with laser-induced thermotherapy (LITT) and vertebroplasty
versus vertebroplasty alone. To investigate the effect of tumor ablation using LITT prior to vertebroplasty on biomechanical
stability and cement fill patterns in a standardized model of spinal metastatic disease. Vertebroplasty in the metastatic
spine is aimed at reducing pain, but is associated with risk of cement extravasation in up to 10%. Six pairs of fresh-frozen
cadaveric thoracolumbar spinal motion segments were tested in axial compression intact, with simulated metastases and following
percutaneous vertebroplasty with or without LITT. Canal narrowing under load, pattern of cement fill, load to failure, and
LITT temperature and pressure generation were collected. In all LITT specimens, cement filled the defect without extravasation.
The canal extravasation rate was 33% in specimens treated without LITT. LITT and vertebroplasty yielded a trend toward improved
posterior wall stability (P = 0.095) as compared to vertebroplasty alone. Moderate rises in temperature and minimal pressure generation was seen during
LITT. In this model, elimination of tumor by LITT, facilitates cement fill, enhances biomechanical stability and reduces the
risk of cement extravasation. 相似文献
1000.
Intussusception after open Roux-en-Y gastric bypass procedure (RYGBP) is a rare complication. We present a retrospective review
of three cases of antegrade intussusception occurring after laparoscopic RYGBP. To our knowledge, these are the first documented
cases of intussusception after laparoscopic RYGBP. We describe the clinical presentation and our management of these three
cases. Furthermore, we believe that the initial clinical presentation, radiographic findings, and management of these patients
may be different than those patients who have undergone an open RYGBP. With increasing popularity of laparoscopic RYGBP, we
are likely to see more of this entity. 相似文献