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81.
The aim of this study is to understand the value of specific sites in extended peripheral and transition zone biopsy schemes in order to define the optimal systematic biopsy regimen correlated with the percentage of positivity of each single bioptic site. A total of 165 consecutive patients underwent transrectal ultrasonography examination to detect prostate cancer followed by a lesion-directed and systematic 14-step biopsy scheme. The detection rate was examined for the lesion-directed and for each zone region biopsy. The frequency of positive biopsies in the various prostate regions was determined to evaluate the diagnostic yield of each biopsy site. Analysis was stratified for prostate-specific antigen (PSA), free-to-total PSA ratio, age, prostate size and digital rectal examination. The biopsy protocol detected 40% of patients (66/165) as positive and 55.1% (91/165) as negative for cancer. Standard sextant biopsy was expected to detect only 51 cancer on 66, lateral peripheral (PZ), transition (TZ) and central zone (CZ) biopsies only 56 cancer on 66, while the combination of sextant, PZ, TZ and CZ biopsies, for a total of 14 zone biopsies, detected 64 on 66 patients with cancer (97%) at recruitment. Sampling only the eight prostate regions with higher frequency of positive cancer biopsy was expected to detect 61 cancer patients against the 64 found with the 14-step scheme. This eight-biopsy regimen outperforms the conventional sextant regimen in cancer detection rate (93 vs 77%) and has an overall detection rate lower by only 3.1% (36.9 vs 40%) compared to the 14-biopsy regimen. This difference in detection rate is even smaller in patients with PSA values <10 ng/ml, age <70 y and prostate size <50 ml. This eight-biopsy scheme, including sampling in PZ and TZ toward the base, should be considered in an initial biopsy scheme to maintain a similar detection rate of an extensive biopsy scheme reducing the number of biopsies.  相似文献   
82.
Bello L  Lucini V  Giussani C  Carrabba G  Pluderi M  Scaglione F  Tomei G  Villani R  Black PM  Bikfalvi A  Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo.  相似文献   
83.
The aim of imaging in a child with urinary tract infection (UTI) is to detect abnormalities that require appropriate treatment or findings that can be acted on to prevent development of complications (hypertension, chronic renal failure or pregnancy-related complications). Imaging protocols in pediatric urinary tract infections are evolving. From strategies based on extensive investigations in all children younger than 7 years of age, we are slowly moving to imaging strategies focused on children at risk of developing renal damage and possibly long-term complications. The article provides an overview on urinary tract infections, their complications and the use of imaging in their management. The different imaging strategies in children with UTIs (including the recommendation of excluding from imaging certain groups of patients) still needs full evaluation. It is interesting to note, however, a slow move from wide use of cystography in all children with UTI, which has been standard practice for many years but was probably not based on solid scientific evidence, toward a more focused use of cystograms in specific groups of children.  相似文献   
84.
Attenuation correction (AC) for myocardial perfusion SPECT (MPS) had not been evaluated separately in women despite specific considerations in this group because of breast photon attenuation. We aimed to evaluate the performance of AC in women by using automated quantitative analysis of MPS to avoid any bias. METHODS: Consecutive female patients--134 with a low likelihood (LLk) of coronary artery disease (CAD) and 114 with coronary angiography performed within less than 3 mo of MPS--who were referred for rest-stress electrocardiography-gated 99mTc-sestamibi MPS with AC were considered. Imaging data were evaluated for contour quality control. An additional 50 LLk studies in women were used to create equivalent normal limits for studies with AC and with no correction (NC). An experienced technologist unaware of the angiography and other results performed the contour quality control. All other processing was performed in a fully automated manner. Quantitative analysis was performed with the Cedars-Sinai myocardial perfusion analysis package. All automated segmental analyses were performed with the 17-segment, 5-point American Heart Association model. Summed stress scores (SSS) of > or =3 were considered abnormal. RESULTS: CAD (> or =70% stenosis) was present in 69 of 114 patients (60%). The normalcy rates were 93% for both NC and AC studies. The SSS for patients with CAD and without CAD for NC versus AC were 10.0 +/- 9.0 (mean +/- SD) versus 10.2 +/- 8.5 and 1.6 +/- 2.3 versus 1.8 +/- 2.5, respectively; P was not significant (NS) for all comparisons of NC versus AC. The SSS for LLk patients for NC versus AC were 0.51 +/- 1.0 versus 0.6 +/- 1.1, respectively; P was NS. The specificity for both NC and AC was 73%. The sensitivities for NC and AC were 80% and 81%, respectively, and the accuracies for NC and AC were 77% and 78%, respectively; P was NS for both comparisons. CONCLUSION: There are no significant diagnostic differences between automated quantitative MPS analyses performed in studies processed with and without AC in women.  相似文献   
85.
Proper femoral and tibial component rotational positioning in TKA is critical for outcomes. Several rotational landmarks are frequently used with different advantages and limitations. We wondered whether coronal axes in the tibia and femur based on the transepicondylar axis in the femur would correlate with anteroposterior deformity. We obtained computed tomography scans of 100 patients with arthritis before they underwent TKA. We measured the posterior condylar angle on the femoral side and the angle between Akagi’s line and perpendicular to the projection of the femoral transepicondylar axis on the tibial side. On the femoral side, we found a linear relationship between the posterior condylar angle and coronal deformity with valgus knees having a larger angle than varus knees, ie, gradual external rotation increased with increased coronal deformity from varus to valgus. On the tibial side, the angle between Akagi’s line and the perpendicular line to the femoral transepicondylar axis was on average approximately 0°, but we observed substantial interindividual variability without any relationship to gender or deformity. A preoperative computed tomography scan was a useful, simple, and relatively inexpensive tool to identify relevant anatomy and to adjust rotational positioning. We do not, however, recommend routine use because on the femoral side, we found a relationship between rotational landmarks and coronal deformity. Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his or her institution has approved the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.  相似文献   
86.
Background  Liver surgery is the gold-standard treatment of colorectal liver metastases. Five-year survival rates may be inadequate to evaluate surgical outcomes because some patients are alive with recurrence and late recurrences are possible. The aim of this study was to analyze 10-year survival outcome in terms of late recurrence rate and prognostic factors of survival. Methods  One hundred twenty-five patients underwent liver resection for colorectal liver metastases between 1985 and 1996. Four patients who experienced postoperative mortality were excluded. The analysis was performed on 121 patients. Results  Five- and 10-year survival rates were 23.1% and 15.7%, respectively. Nineteen patients were alive 10 years after liver resection and 17 were disease-free (5 after re-resection). Five- and 10-year disease-free survival rates were 17.4% and 14.8%, respectively. In patients with recurrence, re-resection significantly improved survival (P < 0.001); 98% of recurrences occurred within the first 5 years, but 15% of patients disease-free at 5 years developed later recurrence. Multivariate analysis evidenced five independent negative prognostic factors of survival: male sex (P = 0.029), synchronous metastases (P = 0.011), >3 metastases (P < 0.001), metastatic infiltration of nearby structures (P < 0.001), and postoperative morbidity (P < 0.001). In 17 patients without negative prognostic factors the 10-year survival rate was 35.3%. Conclusion  Liver resection for colorectal liver metastases may be curative in more than one-third of patients without negative prognostic factors. Postoperative morbidity significantly worsens long-term outcomes. The risk of recurrence after liver resection is high even after 5 years of follow-up, but re-resection can improve the outcome.  相似文献   
87.
In patients with colorectal cancers synchronous neoplastic lesions are an increasingly frequent finding at preoperative staging; 3% of the cases are other cancers while 33-35% of the synchronous lesions are villous adenomas. The treatment of most colorectal adenomas can be performed by endoscopic poplypectomy. In 5% of cases there are synchronous colorectal lesions also requiring surgical treatment. From January 1995 to June 2007 we treated 5 patients with rectal lesions by transanal endoscopic microsurgery (TEM) together with a laparoscopic colectomy for the presence of synchronous lesions at the "Clinica Chirurgica Generale e d'Urgenza" of the University of Perugia,. Surgical timing involved performing a sequential exeresis characterised by a cancer resection, followed by resection of the voluminous adenoma: TEM for rectal cancer followed by a laparoscopic right hemicolectomy with an extracorporeal anastomosis for a voluminous villous adenoma (1 patient) and laparoscopic right hemicolectomy with an extracorporeal anastomosis for cancer followed by TEM for a voluminous villous adenoma (2 patients). One patient with left colon cancer associated with a voluminous villous rectal adenoma first underwent TEM for the rectal adenoma and then a left laparoscopic hemicolectomy with an extracorporeal anastomosis in order to ease the transit of the circular mechanical stapler. Another patient with rectal and right colon adenomas first underwent TEM for a voluminous rectal sessile adenoma and later a right hemicolectomy. The use of this minimally invasive approach allowed rectum preservation and less invasive surgery.  相似文献   
88.
Bile leak after hepatectomy: predictive factors of spontaneous healing   总被引:1,自引:0,他引:1  
BACKGROUND: Bile leakage after hepatectomy usually has spontaneous healing, but some patients require interventional procedures. To identify early predictive factors of conservative management failure. METHODS: This study focused on patients with bile leak after hepatectomy without extrahepatic biliary resection from 1996 through 2006. RESULTS: Bile leakage occurred in 34 of 593 patients (5.7%). Conservative management was successful in 26 patients (76.5%). At univariate analysis overall associated resections, vascular associated resections, and drainage output on days 1, 3, and 10 from leak onset were significant negative predictors of spontaneous healing. At multivariate analysis drainage output greater than 100 mL on day 10 was the only independent prognostic factor of conservative management failure (relative risk, 55.985; P = .008) with 80% sensitivity, 93.3% specificity, and 90% accuracy. CONCLUSIONS: Wait-and-see treatment is successful in most cases. Patients with drainage output greater than 100 mL 10 days after bile leakage diagnosis should be scheduled for interventional treatments.  相似文献   
89.
Duplication of the male urethra is an uncommon congenital malformation. The majority of cases are diagnosed during infancy, and are detected by observing two urethral meatus, or by the appearance of some form of complication, normally of an obstructive nature. Micturitional cystourethrography is an essential test, both in confirming diagnosis of this pathology, and in determining the type of urethral duplication. Excretory urography is also recommended due to its association with other possible urological and extra-urological congenital disorders. Treatment is based on the patient's clinical symptoms, with a waiting period considered advisable for asymptomatic cases. Here we present a case of incomplete urethral duplication, diagnosed from a bladder outlet obstruction, secondary to stenosis of the urethra, which was treated with an endoscopic urethrotomy and distal septotomy, obtaining excellent clinical results.  相似文献   
90.
From February 2002 to December 2005, 424 operations for thyroid disease were performed in our institute. Twenty-two patients were suffering from Basedow's disease, 14 female and 8 male, mean age 36 years (range: 23 to 53 years). In each patient the diagnosis of Basedow's disease was made according to common clinical and laboratory criteria, by evaluation of the thyroid hormones, TSH and TRAB. Before operation all patients were rendered euthyroid with antithyroid drug treatment. Fourteen total thyroidectomies (64%) and 8 near-total thyroidectomies (36%) were performed. Postoperative thyroid function status was evaluated before, 3-4 weeks after the operation and then 3, 6,12 and 24 months postoperatively. The patients were classified as euthyroid (FT3-FT4 and TSH normal), hypothyroid (FT3 and/or FT4 reduced and TSH increased), or hyperthyroid (FT3-FT4 increased). In expert hands, surgical treatment appears to be capable of curing the hyperthyroidism of Basedow's disease effectively, with a very low and largely acceptable risk of complications. Among the different types of surgery, total thyroidectomy and near-total thyroidectomy are equally appropriate to ensure there is no risk of recurrence of hyperthyroidism.  相似文献   
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