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991.
This article presents a semi-automatic method for segmentation and reconstruction of freehand three-dimensional (3D) ultrasound data. The method incorporates a number of interesting features within the level-set framework: First, segmentation is carried out using region competition, requiring multiple distinct and competing regions to be encoded within the framework. This region competition uses a simple dot-product based similarity measure to compare intensities within each region. In addition, segmentation and surface reconstruction is performed within the 3D domain to take advantage of the additional spatial information available. This means that the method must interpolate the surface where there are gaps in the data, a feature common to freehand 3D ultrasound reconstruction. Finally, although the level-set method is restricted to a voxel grid, no assumption is made that the data being segmented will conform to this grid and may be segmented in its world-reference position. The volume reconstruction method is demonstrated in vivo for the volume measurement of ovarian follicles. The 3D reconstructions produce a lower error variance than the current clinical measurement based on a mean diameter estimated from two-dimensional (2D) images. However, both the clinical measurement and the semi-automatic method appear to underestimate the true follicular volume. 相似文献
992.
Ovarian hormones regulate prepulse inhibition (PPI) of the acoustic startle reflex. Results from studies in intact female rodents investigating sex, estrous cycle and ovarian hormone regulation of PPI are inconsistent. In experiment #1, we investigated whether PPI in female rats is influenced by the time of day of testing and the estrous cycle stage of the rat. PPI was examined across the day of proestrus (P) and diestrus 1 (D1) in female rats and compared to males. PPI in males and P females was significantly higher than in D1 females. PPI in males and D1 females was significantly affected by the time of day of testing with PPI being reduced in the afternoon and evening compared to morning. PPI in P females was not significantly affected by the time of day of testing. Previous studies have demonstrated estrous cycle regulation of central nervous system neurotensin (NT) neurons and peripherally administered NT receptor agonists regulate PPI in a manner similar to antipsychotic drugs. Experiment #2 of this study was designed to examine whether endogenous NT is involved in estrous cycle regulation of PPI. The NT receptor antagonist SR 142948A reduced the high levels of PPI during D1 and P. In contrast, when tested at a time of day in which PPI was low in D1 females, administration of both the typical antipsychotic drug haloperidol and the NT receptor antagonist significantly increased PPI. These data support an effect of time of day and estrous cycle stage on PPI in female rats. The estrous cycle variations in PPI are mediated in part by endogenous NT. 相似文献
993.
Kolla SB Seth A Singh MK Gupta NP Hemal AK Dogra PN Kumar R 《International urology and nephrology》2008,40(2):321-327
Introduction The aim of the study was to evaluate the status of Her2/neu protein expression in patients with muscle-invasive urothelial
carcinomas of the bladder treated with radical cystectomy and to determine its prognostic significance.
Material and methods We retrospectively analyzed the data of 90 patients who had undergone cystectomy for invasive transitional cell carcinoma
of the urinary bladder. Immunohistochemical analysis for Her2/neu was done on paraffin-fixed tissues with CB11 antibodies
(BioGenex, San Ramon, CA, USA). Sections with grade 2 and grade 3 staining were considered positive for Her2/neu.
Results Over a median follow-up period of 46 months (24–96 months) 46 patients are living without disease recurrence and six with
recurrent disease either at the local site or with distant metastases. The remaining 38 patients have died. The median overall
survival time was 50 months, and median disease-free survival time was 40 months. The Her2/neu status was significantly related
to the tumor stage (P = 0.001), lymph node involvement (77% in N+ vs 23% in N0; P = 0.001) and the grade of the disease (32% of grade 2 vs 71% of grade 3; P = 0.037). Kaplan–Meier curves showed a significantly worse disease-related survival period (log rank P = 0.011) for patients with Her2 overexpressing tumors than for those without overexpression. In addition to tumor stage [P = 0.001; relative risk (RR) = 2.62] and lymph node status (P = 0.0001; RR = 2.95), Her2 status (P = 0.020; RR = 2.22) was identified as an independent predictor for disease-related survival in a multivariate analysis.
Conclusion These results suggest that Her2 expression might provide additional prognostic information for patients with muscle-invasive
bladder cancer. Future studies on Her2 expression with chemosensitivity and the efficacy of Her2-targeted therapies in urothelial
carcinomas are warranted. 相似文献
994.
OBJECTIVES: We compared long-term outcome in patients with initial pT1G3 bladder cancer (BC) treated with early versus deferred cystectomy (CX) for recurrent pT1G3 or muscle-invasive BC after an initial bladder-sparing approach. The aim of this study was to compare survival rates and to analyse the influence of the recognised risk factors multifocality, tumour size, and carcinoma in situ (CIS) in initial transurethral resection of the bladder. METHODS: Between 1995 and 2005, a total of 105 patients were diagnosed with initial pT1G3 BC featuring>or=2 risk factors. Forty-five percent had multiple tumours, 73% tumours>3 cm in size, and 46% CIS. All patients were offered early CX. Fifty-one percent of patients opted for early and 49% underwent deferred CX for recurring BC. Risk factors were distributed evenly between the groups. RESULTS: Upstaging in the CX specimen was found in 30% of cases. No risk factor was related to upstaging. The 10-yr cancer-specific survival rate was 78% in early CX and 51% in deferred CX (p<0.01). No risk factor predicted cancer-related death in early CX. In survival analysis, CIS was related to a lower cancer-specific survival rate in deferred CX (p<0.001). CONCLUSIONS: Early as opposed to deferred CX seems to prolong the cancer-specific survival rate in high-risk pT1G3 BC. Patients with CIS should be considered for early CX owing to reduced cancer-specific survival in case of deferred CX. 相似文献
995.
Objectives A possibility that aging affects (a) expression of the α1D-adrenergic receptor (AR1D), (b) AR1D-mediated contractions and
(c) sympathetic innervation in the urinary bladder in rats was studied.
Materials and methods Contraction produced by phenylephrine and inhibition of these contractions by a non-selective α1-adrenergic antagonist prazosin
and a selective AR1D antagonist BMY7378 were compared between 6- and 24-month-old Fisher rats. Expressions of VMAT and AR1D
in the bladder were assessed by immunofluorescence and Western blot.
Results Phenylephrine-induced contractions were larger and inhibition of these contractions by BMY7378 was significantly greater in
24-month-old rats. Aging increased expression of AR1D in the bladder. Density of VMAT-immunoreactive neurites was decreased
in smooth muscle but elevated in the suburothelial region of 24-month-old rats.
Conclusions The results suggest that influence of adrenergic activity on bladder contractility increases with aging is due to overexpression
of the AR1D. Influence of adrenergic activity on the urothelial function may also be enhanced with aging. 相似文献
996.
We studied the safety and feasibility of laparoscopic radical cystectomy (LRC) in patients with loco-regionally advanced bladder
cancer and report the short-term oncological outcome. This study comprised a total of 13 patients (10 males, 3 females), who
presented with myriad of symptoms and on imaging they were found to have radiologically evident advanced disease (6 pelvic
lymphadenopathies, 10 extravesical tumor extensions, three prostate/seminal vesical invasions). In view of recalcitrant symptoms
(hematuria, frequency and irritative voiding) all patients underwent LRC and bilateral modified pelvic lymphadenectomy with
ileal conduit urinary diversion. Mean age of the patients was 56.3 years. Mean operative time was 310 min with an average
blood loss of 556 ml. No major intra-operative complications were noted. One patient died in the post-operative period due
to sepsis. Histopathology report revealed pT3b N0 in two patients; pT3b N1 in four; pT3b N2 in three; pT4a N0 in one, and
pT4aN1 in three patients. Adjuvant chemotherapy was administered in nine patients. At mean follow up of 18 months (range 6–28),
seven patients are alive and cancer-free, while two patients are alive with metastases. LRC provides an alternative approach
for treatment of patients with loco-regionally advanced bladder cancer, who suffer from recurrent hematuria and severe irritative
voiding symptoms, in whom open surgery was the standard approach hitherto. However, it should be considered experimental and
should be attempted only by surgeons who have significant experience of laparoscopic pelvic surgery and advanced skills, and
after discussing the potential risks and benefits with the patient. 相似文献
997.
Ovarian sex cord stromal tumor (OSCST), sclerosing type, is an extremely rare ovarian tumor. Sex hormone production by OSCST can result in isosexual or heterosexual precocious puberty in younger patients. We present a case of a 7-month-old female infant found to have a sclerosing-type OSCST that presented with vaginal bleeding and very prominent vellus hair at the mons pubis. This represents the youngest patient reported in the literature with this subset of OSCST. 相似文献
998.
999.
1000.
Winter DC Walsh R Lee G Kiely D O'Riordain MG O'Sullivan GC 《Annals of surgical oncology》2007,14(2):441-446
Background Colorectal cancers that adhere to the urinary bladder require en bloc partial or total cystectomy to achieve negative tumor
margins.
Methods This prospective study evaluated the outcome of combined bladder resection for carcinoma of the colon or rectum at a unit
specializing in gastrointestinal cancer.
Results Patients (n = 63) with colorectal tumors adherent to the bladder at operation and without distal metastases were followed.
Fifty-eight patients (92%) had tumors of the sigmoid colon or upper rectum. Operative morbidity and mortality rates were 18%
and 1.5%, respectively. Histological staging demonstrated bladder adherence in 46% (29/63) and invasion in 54% (34/63). Overall
disease-specific survival was 54%, with a mean follow-up of 7.6 (range 5–12) years. Five-year survival for margin negative
patients was 72% (26/36) and 27% (4/15) for node negative and positive tumors, respectively. The bladder was closed primarily
in 48 patients and reconstructed by enterocystoplasty in five, with ten patients requiring urinary diversion.
Conclusions En bloc bladder resection for adherent or invading tumors of the colon and rectum achieves good local control, but an infiltrative
extravesical margin denotes poor prognosis. The potential for cure in completely excised node negative tumors is good. Bladder
reconstruction is achievable in most patients. 相似文献