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991.
Purpose Gradually progressing contraction of airway smooth muscle is suggested to be due to the Rho-kinase signaling pathway. In our
preliminary study in rat tracheas, landiolol, a β1-adrenoceptor antagonist, at high doses caused gradually progressing contraction, and this contraction reached a plateau after
20 min. Therefore, this study was carried out to clarify whether landiolol could stimulate the Rho-kinase pathway or the phosphatidylinositol
(PI) response in the rat trachea.
Methods Seventy-eight male Wistar rats weighing 250–350 g were used for the experiments. Their tracheas were cut into 3-mm-wide ring
segments or 1-mm-wide slices. Measurements of isometric tension and [3H] inositol monophosphate (IP1) production were conducted, using these tracheal rings or slices. Data values are expressed as means ± SD, and statistical
significance (P < 0.05) was determined using analysis of variance (ANOVA).
Results Landiolol (700 μM)-induced contraction was completely inhibited by fasudil at 30 μM, while the landiolol-induced contraction
was not inhibited by 4-diphenylacetoxy-N-methyl-piperidine methobromide (4-DAMP), ketanserin, or nicardipine. Landiolol did
not stimulate IP1 production.
Conclusion These results suggest that high concentrations of landiolol could cause airway smooth muscle contraction through the Rho-kinase
pathway, but not through the PI response coupled with muscarinic M3 receptors, 5-HT receptors or the activation of L-type Ca2+ channels. 相似文献
992.
Based on a review of recently published articles, we evaluated the current status of high-intensity focused ultrasound (HIFU)
as a primary treatment option for localized prostate cancer and as a salvage therapy when radiation has failed. With mid-and
long-term progression-free survival rates around 70%, negative postoperative prostate biopsies almost 90%, and an excellent
morbidity profile, primary HIFU appears to be a valid alternative to active surveillance protocols in low-risk patients and
standard therapies in patients with life expectancies of 10 or fewer years. Moreover, HIFU has a considerable potential for
local-only recurrence after radiation failure. HIFU is a recent technology, and many improvements will undoubtedly expand
its future indications and use for the management of prostate cancer. 相似文献
993.
Marker DR Seyler TM Ulrich SD Srivastava S Mont MA 《Clinical orthopaedics and related research》2008,466(5):1093-1103
Core decompression procedures have been used in osteonecrosis of the femoral head to attempt to delay the joint destruction that may necessitate hip arthroplasty. The efficacy of core decompressions has been variable with many variations of technique described. To determine whether the efficacy of this procedure has improved during the last 15 years using modern techniques, we compared recently reported radiographic and clinical success rates to results of surgeries performed before 1992. Additionally, we evaluated the outcomes of our cohort of 52 patients (79 hips) who were treated with multiple small-diameter drillings. There was a decrease in the proportion of patients undergoing additional surgeries and an increase in radiographic success when comparing pre-1992 results to patients treated in the last 15 years. However, there were fewer Stage III hips in the more recent reports, suggesting that patient selection was an important reason for this improvement. The results of the small-diameter drilling cohort were similar to other recent reports. Patients who had small lesions and were Ficat Stage I had the best results with 79% showing no radiographic progression. Our study confirms core decompression is a safe and effective procedure for treating early stage femoral head osteonecrosis. 相似文献
994.
Fausto Catena Monica Di Battista Pietro Fusaroli Luca Ansaloni Valerio Di Scioscio Donatella Santini Maria Pantaleo Guido Biasco Giancarlo Caletti Antonio Pinna 《Journal of gastrointestinal surgery》2008,12(3):561-568
Background Although the feasibility of laparoscopic resection of gastric gastrointestinal stromal tumors (GISTs) has been established,
various aspects are debated. This paper describes the problems of minimally invasive resection of gastric GISTs and compares
this experience with an extensive literature review.
Study Design Between August 2001 and December 2006, 21 consecutive patients undergoing laparoscopic resection of gastric GISTs were enrolled
in a prospective study. A literature review of laparoscopic treatment was performed on Pubmed using keywords GIST and surgery.
A comparison with authors’ experience with open wedge-segmental resection of GISTs (25 cases from November 1995 to December
2000) was also carried out. Statistical analysis was based on chi-squared test and t Student evaluation.
Results Twenty-one patients, mean age 50.1 years (range, 34–68 years), were submitted to laparoscopic wedge- segmental gastric resections.
Mean tumor size was 4.5 cm (range, 2.0–8.5 cm). Mean operative time was 151 min (range, 52–310 min), the mean blood loss was
101 mL (range, 10–250 mL), and the mean hospital stay was 4.8 days (range 3–7 days). There were no major operative complications
or mortalities. All lesions had negative resection margins. At a mean follow-up of 35 months, all patients were disease-free.
Morbidity, mortality, length of stay, and oncologic outcomes were comparable to the open surgery retrospective evaluation
(p = not significant).
Conclusions As found also in the literature review, the laparoscopic resection is safe and effective in treating gastric GISTs. Given
these findings as well as the advantages afforded by laparoscopic surgery, a minimally invasive approach should be the preferred
surgical treatment in patients with small- and medium-sized gastric GISTs. 相似文献
995.
Roland Seiler Andreas Rickenbacher Sidney Shaw Simon Haefliger Bruno M. Balsiger 《Journal of gastrointestinal surgery》2008,12(6):1087-1093
Gut motility is modulated by adrenergic mechanisms. The aim of our study was to examine mechanisms of selective adrenergic
receptors in rat jejunum. Spontaneous contractile activity of longitudinal muscle strips from rat jejunum was measured in
5-ml tissue chambers. Dose–responses (six doses, 10−7–3 × 10−5M) to norepinephrine (NE, nonspecific), phenylephrine (PH, α1), clonidine (C, α2), prenalterol (PR, β1), ritodrine (RI, β2), and ZD7714 (ZD, β3) were evaluated with and without tetrodotoxin (TTX, nerve blocker). NE(3 × 10−5M) inhibited 74 ± 5% (mean ± SEM) of spontaneous activity. This was the maximum effect. The same dose of RI(β2), PH(α1), or ZD(β3) resulted in an inhibition of only 56 ± 5, 43 ± 4, 33 ± 6, respectively. The calculated concentration to induce 50% inhibition
(EC50) of ZD(β3) was similar to NE, whereas higher concentrations of PH(α1) or RI(β2) were required. C(α2) and PR(β1) had no effect. TTX changed exclusively the EC50 of RI from 4.4 ± 0.2 to 2.7 ± 0.8% (p < 0.04). Contractility was inhibited by NE (nonspecific). PH(α1), RI(β2), and ZD(β3) mimic the effect of NE. TTX reduced the inhibition by RI. Our results suggest that muscular α1, β2, and β3 receptor mechanisms mediate adrenergic inhibition of contractility in rat jejunum. β2 mechanisms seem to involve also neural pathways.
Part of this work was presented as a poster at the annual meeting of the Society for Surgery of the Alimentary Tract, Orlando,
FL, May 17–22, 2003, and published as an abstract in Gastroenterology 2003, 124(4):M1342. 相似文献
996.
Kevin E. Behrns Stan W. Ashley John G. Hunter David Carr-Locke 《Journal of gastrointestinal surgery》2008,12(4):629-633
The indications for early endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis are unclear, and
the examination is often requested or performed without substantial supporting evidence. Several trials have been performed
to determine the benefit of early ERCP in pancreatitis, yet the results of these studies are inconsistent. To more closely
analyze these studies, we performed an evidence-based review of the outcomes of early ERCP in gallstone pancreatitis. To obtain
the best available evidence, a PubMed search using the MeSH terms “gallstones” and “pancreatitis” was performed and further
refined to identify appropriate studies. We included five randomized trials, a meta-analysis, and a Cochrane Database Systematic
Review in our detailed examination of the pertinent literature. Collectively, these studies suggest that early ERCP does not
alter mortality in gallstone pancreatitis. In addition, few patients with mild pancreatitis benefit from the procedure, whereas
some studies indicate that patients with severe pancreatitis or documented biliary obstruction may experience fewer complications
if ERCP is performed. The data in the studies are confounding because of heterogeneity of the patient population and the inability
to confirm gallstones in up to one third of patients. In conclusion, ERCP is not indicated for patients with mild pancreatitis.
In select patients with severe disease or biliary obstruction, ERCP may be indicated. A multicenter trial designed to study
the effect of early ERCP in severe pancreatitis only may provide additional useful information in patients with documented
gallstones.
Presented at the Postgraduate Course of the 48th Annual Meeting of The Society for Surgery of the Alimentary Tract (Digestive
Disease Week 2007), Washington DC, USA, May 20, 2007. 相似文献
997.
Over the last 15 years, great improvements in genetic engineering and genetic manipulation strategies have led to significant
advances in the understanding of the genetics governing embryological limb development. This field of science continues to
develop, and the complex genetic interactions and signalling pathways are still not fully understood. In this review we will
discuss the roles of the principle genes involved in the three-dimensional patterning of the developing limb and will discuss
how errors in these signalling cascades correlate to congenital limb deformity in humans. This review is aimed at orthopaedic
surgeons wishing to understand the principles of congenital limb deformity related to genetic signalling errors. It is by
no means a comprehensive study of the molecular genetics governing the complex interactions involved in each step of limb
development. There are however many syndromes involving limb deformity for which the molecular causes are unknown. 相似文献
998.
Fady K. Balaa T. Clark Gamblin Allan Tsung J. Wallis Marsh David A. Geller 《Journal of gastrointestinal surgery》2008,12(2):338-343
Background Application of linear stapling devices for extrahepatic vascular control in liver surgery has been well-established. However,
the technique for use of stapling devices in hepatic parenchymal transection is not well defined.
Purpose To describe the safety and efficacy of our technique for use of vascular stapling devices in hepatic parenchymal transection
during open right hepatic lobectomy is the purpose of this study.
Methodology We reviewed our experience with 101 consecutive open right hepatic lobectomies performed by a single surgeon between January
2003 and July 2006, in which vascular staplers were utilized for the parenchymal transection phase.
Results Of the 101 patients who underwent resection, 53 (52%) were female. The mean age was 58 years. Malignant disease was the indication
for resection in the majority of patients (88%). Of those with cancer, 78% (69 of 89) had metastatic colorectal cancer, 6%
(5 of 89) had metastatic neuroendocrine tumor, 4% (4 of 89) had hepatocellular carcinoma, 4% (4 of 89) had cholangiocarcinoma,
and the remaining 8% were other metastatic cancers. Twelve patients (12%) underwent resection for hepatic adenoma or symptomatic
benign disease (FNH or hemangioma). Forty-eight patients (48%) underwent a major ancillary procedure at the time of hepatic
resection. Thirty-nine patients (39%) had a nonanatomic wedge resection of a left lobe lesion, 27 patients (27%) had one or
more lesions treated with radiofrequency ablation (RFA), and 6 patients (6%) were treated with a synchronous bowel resection.
The median total operative time was 336 min (range 155–620 min). A Pringle maneuver for temporary vascular inflow occlusion
was utilized in all cases, with a median time of 9 min (range 4–17 min). Ten patients (10%) required blood transfusion during
surgery or in the postoperative period. The maximum transfusion was 2 U of packed red blood cells (PRBC) in seven patients
and 1 U of PRBC in three patients. The mean nadir postoperative hematocrit was 28.2. All patients with malignant disease had
tumor-free margins at the completion of the procedure. The average hospital length of stay was 6.0 days. One patient (1%)
developed a clinically significant bile leak requiring a postoperative endoscopic retrograde cholangiography (ERCP). No patient
required reoperation. The 30 and 60-day postoperative survival was 100%.
Conclusion These findings indicate that application of vascular stapling devices for parenchymal transection in major hepatic resection
is a safe technique, with low transfusion requirements and minimal postoperative bile leak. The technique allows for rapid
transection of the entire right hepatic lobe in under 10 min. Short video clips of the technique will be demonstrated.
Presented at the 2007 American Hepato–Pancreato–Biliary Association, Las Vegas, Nevada, April 19–22, 2007 (oral presentation/video
presentation). 相似文献
999.
The aim of this study was to evaluate the impact of enuresis nocturna on quality of life of the mothers. Mothers who have
a child with monosymptomatic nocturnal enuresis (n = 28) and mothers who have a child without any health problems (n = 38) were enrolled in the study. Groups were in balance for background variables (child’s age, gender, and number of siblings;
mother’s age, marital status, highest year of education completed, and occupation; presence of health insurance; and type
of residence). Short-Form Health Survey (SF-36) Questionnaire, the Beck Depression Inventory (BDI), and Spielberg’s State-Trait
Anxiety Inventory (STAI) were applied to all mothers. The mothers of children with enuresis had significantly lower quality-of-life
scores in the SF-36 for the bodily pain (p = 0.015) and role emotional (p = 0.014) subscales. We observed significant difference between groups according to BDI; mean score was higher in mothers
who have a child with enuresis nocturna (p = 0.017). There was no significant difference between groups according to the STAI. Significant differences according to
bodily pain and role emotional subscales of SF-36, and the BDI scores, show that the mothers were negatively affected by having
a child with monosymptomatic nocturnal enuresis. 相似文献
1000.
The aim of this study was to compare the operative results in regard to reducing anastomotic leakage and stricture formation
using a newly designed layered manual esophagogastric anastomosis versus a stapler esophagogastrostomy versus the conventional
hand-sewn whole-layer anastomosis after resection for esophageal or gastric cardiac carcinoma. From January 2004 to September
2006, a total of 1024 patients with esophageal or gastric cardia carcinoma underwent a layered esophagogastric anastomosis
with the assistance of a three-leaf clipper in a single university medical center. The mucosal layers of the esophagus and
stomach were sutured continuously with 4/0 Vicryl plus antibacterial suture (polyglyconate). From May 2002 to December 2003,
there were also 170 patients and 69 patients who underwent stapler and conventional whole-layer anastomosis, respectively;
they served as control groups. The results were analyzed retrospectively. The operative mortality rate was 0.7% in the layered
group compared to 5.9% and 7.2% for the stapler group and the whole-layer group (p < 0.01), The anastomotic leakage rates were 0%, 3.5%, and 5.8% for the layered group, stapler group, and whole-layer group,
respectively (p < 0.01). All patients were followed postoperatively. Six patients in the layered group (0.6%) developed mild stricture formation
compared to 16 patients in stapled group (9.9%) and 5 patients in the conventional whole-layer group (7.8%) (p < 0.01). The application of layered esophagogastric anastomosis could reduce the incidence of anastomotic leakage and stricture
after esophagectomy compared with the stapler and whole-layer manual anastomoses. It is easy to apply and could be used as
an alternative for esophagogastric anastomosis after resection for esophageal or cardiac carcinoma.
This abstract was accepted as a free paper and oral presentation at International Surgical Week 2007, Abstract 320, Montreal,
Canada, August 2007 相似文献