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31.
32.
33.
First experience with gamma probe guided sentinel lymph node surgery in penile cancer 总被引:3,自引:0,他引:3
Wawroschek F Vogt H Bachter D Weckermann D Hamm M Harzmann R 《Urological research》2000,28(4):246-249
Because of the curative approach, the detection of lymph node metastases in squamous cell carcinoma (SCC) of the penis is
of significant clinical relevance. Sentinel lymph node (SLN) identification by means of lymphangiography has been proven to
be insufficiently safe. However, the high morbidity of inguinal lymphadenectomy and the considerable individual variability
regarding the location of lymph node metastases justify the necessity of a technique that enables the identification of SLNs.
Since 1998, SLNs have been intraoperatively identified and selectively dissected, after peritumoral injection of technetium-99m
nanocolloid and using lymphoscintigraphy, in three patients (one with malignant melanoma and two with SCC). At least one SLN
could be detected in each patient. The maximum surgical time was 30 min. There were no severe complications. Lymph node metastases
did not occur in any patient. Upon a mean follow-up of 10 months, all patients are currently free of tumor. Owing to the long-term
results of sentinel lymphadenectomy in malignant melanoma of other locations and our preliminary results with respect to penile
carcinoma, we consider the current method appropriate as the only primary operation for lymph node staging in early stages
and, in combination with modified inguinal lymphadenectomy, in locally advanced stages.
Received: 24 November 1999 / Accepted: 21 April 2000 相似文献
34.
Immune deficiencies in chronic intestinal pseudo-obstruction 总被引:1,自引:0,他引:1
ML Forchielli MC Young AF Flores D. Richardson CW Lo 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(10):1077-1081
Aim: Chronic intestinal pseudo-obstruction has been associated with urinary disorders, myopathy, and ophthalmoplegia in adults and cholelithiasis in children. We observed a high percentage of total-parenteral-nutrition-dependent patients with pseudo-obstruction and recurrent infections requiring gammaglobulin infusions. Methods: AH records for 23 children with chronic intestinal pseudo-obstruction (10 females and 13 males, mean age 9.8 y ± 4.9 y, range 4–24 y) referred for a nutritional evaluation from 1992 to 1995 were reviewed. Chronic intestinal pseudo-obstruction was diagnosed by clinical, radiographic findings and antroduodenal manometry. Intestinal full-thickness biopsies were performed in seven children. Results: Hypogammaglobulinemia was diagnosed in 18 patients (78%): 16 patients had various immunoglobulin deficiencies and 2 had selective antibody deficiency. Intravenous gammaglobulin was administered in 14 patients. Other medical conditions affecting the children are summarized as follows: autonomic dysfunction in 10 patients (43%), recurrent hypoglycemia in 9 (39%), asthma in 9 (39%), cholecystitis in 7 (30%), low serum carnitine level in 6 (26%), urinary dysfunction in 6 (26%), pancreatitis in 5 (22%), behavioral problems in 5 (22%), myopathy in 2 (9%), idiopathic thrombocytopenia in 2 (8%), velopharyngeal insufficiency in 1 (4%), oculocutaneous albinism in 1 (4%), Pierre-Robin syndrome in 1 (4%), and protein C deficiency in 1 (4%). Munchausen syndrome was suspected in two patients. Conclusions: Chronic intestinal pseudo-obstruction appears to be associated with immune deficiencies. It is unclear if the immune deficiencies, intestinal pseudo-obstruction, and the other medical conditions have a common underlying etiology. Repeated infections may be due to impaired immune function in children with chronic intestinal pseudo-obstruction. We recommend screening for immune deficiencies in children with chronic intestinal pseudo-obstruction. 相似文献
35.
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
36.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
37.
Evaluation of the accuracy of gadobenate dimeglumine-enhanced MR imaging in the detection and characterization of focal liver lesions 总被引:8,自引:0,他引:8
Pirovano G Vanzulli A Marti-Bonmati L Grazioli L Manfredi R Greco A Holzknecht N Daldrup-Link HE Rummeny E Hamm B Arneson V Imperatori L Kirchin MA Spinazzi A 《AJR. American journal of roentgenology》2000,175(4):1111-1120
OBJECTIVE. We evaluated the extent to which hepatic lesion characterization and detection is improved by using gadobenate dimeglumine for enhancement of MR images. MATERIALS AND METHODS. Eighty-six patients were imaged before gadobenate dimeglumine administration, immediately after the 2 mL/sec bolus administration of a 0.05 mmol/kg dose (dynamic imaging), and at 60-120 min after the IV infusion at 10 mL/min of a further 0.05 nmol/kg dose (delayed imaging). The accuracy for lesion characterization was assessed for a total of 107 lesions. Sensitivity for lesion detection was assessed for a total of 149 lesions detected on either intra-operative sonography, iodized oil CT, CT during arterial portography, or follow-up contrast-enhanced CT as the gold standard. RESULTS. The accuracy in differentiating benign from malignant liver lesions increased from 75% and 82% (the findings of two observers) on unenhanced images alone, to 89% and 80% on dynamic images alone (p<0.001, p = 0.8), and to 90.7% when combining the unenhanced and dynamic image sets (p<0.001, p = 0.023). Delayed images did not further improve accuracy (90% and 91%; p = 0.002, p< 0.05). A similar trend was apparent in terms of accuracy for specific diagnosis: values ranged from 49% and 62% on unenhanced images alone, to 76% and 70% on combined unenhanced and dynamic images (p<0.001, p = 0.06), and to 75% and 70% on inclusion of delayed images (p<0.001, p = 0.12). The sensitivity for lesion detection increased from 77% and 81% on unenhanced images alone, to 87% and 85% on combined unenhanced and dynamic images (p = 0.001, p = 0.267), and to 92% and 89% when all images were considered (p<0.001, p = 0.01). CONCLUSION. Contrast-enhanced dynamic MR imaging with gadobenate dimeglumine significantly increases sensitivity and accuracy over unenhanced imaging for the characterization of focal hepatic lesions, and delayed MR imaging contributes to the improved detection of lesions. 相似文献
38.
Multifocal nodular fatty infiltration of the liver mimicking metastatic disease on CT: imaging findings and diagnosis using MR imaging 总被引:1,自引:0,他引:1
Kröncke TJ Taupitz M Kivelitz D Scheer I Daberkow U Rudolph B Hamm B 《European radiology》2000,10(7):1095-1100
The aim of this study was to describe the MR appearance of multifocal nodular fatty infiltration of the liver (MNFIL) using
T1-weighted in-phase (IP) and opposed-phase (OP) gradient-echo as well as T2-weighted turbo-spin-echo sequences with fat suppression
(FSTSE) and without (HASTE). Magnetic resonance imaging examinations at 1.5 T using T1-weighted IP and OP-GRE with fast low
angle shot (FLASH) technique, and T2-weighted FSTSE, T2-weighted HASTE of 137 patients undergoing evaluation for focal liver
lesions were reviewed. Five patients were identified in whom CT indicated metastatic disease; however, no liver malignancy
was finally proven. Diagnosis was confirmed by biopsy (n = 3), additional wedge resection (n = 1) or follow-up MRI 6–12 months later (n = 5). Regarding the identified five patients, the number of focal liver lesions was 2 (n = 2) and more than 20 (n = 3). The MR imaging characteristics were as follows: OP-image: markedly hypointense (n = 5); IP image: isointense (n = 2) or slightly hyperintense (n = 3); T2-weighted FSTSE-image: isointense (n = 5); T2-weighted HASTE image isointense (n = 1); slightly hyperintense (n = 4). On OP images all lesions were sharply demarcated and of almost spherical configuration (n = 5). Further evaluation by histology or follow-up MR imaging did not give evidence of malignancy in any case. Histology
revealed fatty infiltration of the liver parenchyma in three patients. Magnetic resonance follow-up showed complete resolution
in two patients and no change in three patients. Multifocal nodular fatty infiltration can simulate metastatic disease on
both CT and MR imaging. The combination of in-phase (IP) and opposed-phase (OP) gradient-echo imaging can reliably differentiate
MNFIL from metastatic disease.
Received: 15 September 1999 Revised: 3 February 2000; Accepted: 7 February 2000 相似文献
39.
The rat model of combined central fluid percussion traumatic brain injury (TBI) and bilateral entorhinal cortical lesion (BEC) produces profound, persistent cognitive deficits, sequelae associated with human TBI. In contrast to percussive TBI alone, this combined injury induces maladaptive hippocampal plasticity. Recent reports suggest a potential role for dopamine in CNS plasticity after trauma. We have examined the effect of the dopamine enhancer l-deprenyl on cognitive function and neuroplasticity following TBI. Rats received fluid percussion TBI, BEC alone, or combined TBI + BEC lesion and were treated once daily for 7 days with l-deprenyl, beginning 24 h after TBI alone and 15 min after BEC or TBI + BEC. Postinjury motor assessment showed no effect of l-deprenyl treatment. Cognitive performance was assessed on days 11-15 postinjury and brains from the same cases examined for dopamine beta-hydroxylase immunoreactivity (DBH-IR) and acetylcholinesterase (AChE) histochemistry. Significant cognitive improvement relative to untreated injured cases was observed in both TBI groups following l-deprenyl treatment; however, no drug effects were seen with BEC alone. l-Deprenyl attenuated injury-induced loss in DBH-IR over CA1 and CA3 after TBI alone. However, after combined TBI + BEC, l-deprenyl was only effective in protecting CA1 DBH-IR. AChE histostaining in CA3 was significantly elevated with l-deprenyl in both injury models. After TBI + BEC, l-deprenyl also increased AChE in the dentate molecular layer relative to untreated injured cases. These results suggest that dopaminergic/noradrenergic enhancement facilitates cognitive recovery after brain injury and that noradrenergic fiber integrity is correlated with enhanced synaptic plasticity in the injured hippocampus. 相似文献
40.
Taupitz M Schnorr J Abramjuk C Wagner S Pilgrimm H Hünigen H Hamm B 《Journal of magnetic resonance imaging : JMRI》2000,12(6):905-911
The purpose of this study was to evaluate the signal enhancement characteristics of very small superparamagnetic iron oxide particles (VSOP)-C63, a new monomer-coated, iron oxide-based magnetic resonance (MR) blood pool contrast medium with a very small particle size and optimized physical properties. Equilibrium MR angiography (MRA) of rats (thoracic and abdominal vessels) was performed at 1.5 T with a three-dimensional gradient-recalled echo (3D GRE) technique (TR/TE 6.6/2.3 msec, flip angle 25 degrees ) before and after (every 3-5 minutes up to 50 minutes) i.v. injection of VSOP-C63 [dosages: 15, 30, 45, 60, 75, and 90 micromol Fe/kg; diameter: 8 nm; relaxivities at 0.47 T: R1 = 30 l/(mmol * s); R2 = 39 l/(mmol * s)]. First-pass MRA images (3D-GRE, TR/TE 4.5/1.7 msec, flip angle 25 degrees ) were obtained with 45 micromol Fe/kg VSOP-C63 in comparison with 0.2 mmol Gd/kg of gadolinium diethylene triamine pentaacetic acid (Gd DTPA; before and every 5 seconds p.i.). MRA (3D GRE, TR/TE 4.5/1.7 msec, flip angle 25 degrees) of coronary vessels in rabbits was performed after i.v. injection of 45 micromol Fe/kg of VSOP-C63. In rats maximal S/N ratio in thoracic and abdominal arteries directly after i.v. injection of VSOP-C63 was 25 +/- 1, 43 +/- 2, 49 +/- 4, 57 +/- 3, 64 +/- 3, and 63 +/- 3 for the different dosages. Blood half-life was dose dependent (15 +/- 2, 20 +/- 3, 29 +/- 6, 37 +/- 5, 61 +/- 16, and 86 +/- 21 minutes). At a dose of 30 micromol Fe/kg even small intrarenal arteries were sharply delineated. First-pass MRA showed no significant difference in the S/N ratio between Gd-DTPA (71.5 +/- 11.5) and VSOP-C63 (65.1 +/- 18. 3). The proximal segments of the coronary arteries in rabbits were clearly depicted at a dose of 45 micromol Fe/kg. The monomer-coated, iron oxide-based contrast medium VSOP-C63 exhibits favorable properties as a blood pool agent for both equilibrium and first-pass MRA. J. Magn. Reson. Imaging 2000;12:905-911. 相似文献