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81.
Penile shortening following radical prostatectomy and straightening procedures for Peyronie’s disease can be a devastating and unwelcome side effect of these operations. The majority of men undergoing radical prostatectomy for prostate cancer have a measured loss of penile length, which also can occur in men with Peyronie’s disease and may be exacerbated by surgery. Recent studies have investigated the mechanisms resulting in penile shortening, and various treatments have emerged to prevent and treat postoperative penile shortening. This article reviews the recent literature on penile length loss after radical prostatectomy and following correction of penile deformity for Peyronie’s disease.  相似文献   
82.
Learning processes have been implicated in the development and course of posttraumatic stress disorder (PTSD); however, little is currently known about punishment‐based learning in PTSD. The current study investigated impairments in punishment‐based learning in U.S. veterans. We expected that veterans with PTSD would demonstrate greater punishment‐based learning compared to a non‐PTSD control group. We compared a PTSD group with and without co‐occurring depression (n = 27) to a control group (with and without trauma exposure) without PTSD or depression (n = 29). Participants completed a computerized probabilistic punishment‐based learning task. Compared to the non‐PTSD control group, veterans with PTSD showed significantly greater punishment‐based learning. Specifically, there was a significant Block × Group interaction, F(1, 54) = 4.12, p = .047, η2 = .07. Veterans with PTSD demonstrated greater change in response bias for responding toward a less frequently punished stimulus across blocks. The observed hypersensitivity to punishment in individuals with PTSD may contribute to avoidant responses that are not specific to trauma cues.  相似文献   
83.
Jaffer A. Ajani, MD; Kathryn A. Winter, MS; Leonard L. Gunderson, MD; John Pedersen, MD; Al B. Benson III, MD; Charles R. Thomas Jr, MD; Robert J. Mayer, MD; Michael G. Haddock, MD; Tyvin A. Rich, MD; Christopher Willett, MD

JAMA. 2008;299(16):1914-1921.

Context  Chemoradiation as definitive therapy is the preferred primary therapy for patients with anal canal carcinoma; however, the 5-year disease-free survival rate from concurrent fluorouracil/mitomycin and radiation is only approximately 65%.

Objective  To compare the efficacy of cisplatin-based (experimental) therapy vs mitomycin-based (standard) therapy in treatment of anal canal carcinoma.

Design, Setting, and Participants  US Gastrointestinal Intergroup trial RTOG 98-11, a multicenter, phase 3, randomized controlled trial comparing treatment with fluorouracil plus mitomycin and radiotherapy vs treatment with fluorouracil plus cisplatin and radiotherapy in 682 patients with anal canal carcinoma enrolled between October 31, 1998, and June 27, 2005. Stratifications included sex, clinical nodal status, and tumor diameter.

Intervention  Participants were randomly assigned to 1 of 2 intervention groups: (1) the mitomycin-based group (n = 341), who received fluorouracil (1000 mg/m2 on days 1-4 and 29-32) plus mitomycin (10 mg/m2 on days 1 and 29) and radiotherapy (45-59 Gy) or (2) the cisplatin-based group (n = 341), who received fluorouracil (1000 mg/m2 on days 1-4, 29-32, 57-60, and 85-88) plus cisplatin (75 mg/m2 on days 1, 29, 57, and 85) and radiotherapy (45-59 Gy; start day = day 57).

Main Outcome Measures  The primary end point was 5-year disease-free survival; secondary end points were overall survival and time to relapse.

Results  A total of 644 patients were assessable. The median follow-up for all patients was 2.51 years. Median age was 55 years, 69% were women, 27% had a tumor diameter greater than 5 cm, and 26% had clinically positive nodes. The 5-year disease-free survival rate was 60% (95% confidence interval [CI], 53%-67%) in the mitomycin-based group and 54% (95% CI, 46%-60%) in the cisplatin-based group (P = .17). The 5-year overall survival rate was 75% (95% CI, 67%-81%) in the mitomycin-based group and 70% (95% CI, 63%-76%) in the cisplatin-based group (P = .10). The 5-year local-regional recurrence and distant metastasis rates were 25% (95% CI, 20%-30%) and 15% (95% CI, 10%-20%), respectively, for mitomycin-based treatment and 33% (95% CI, 27%-40%) and 19% (95% CI, 14%-24%), respectively, for cisplatin-based treatment. The cumulative rate of colostomy was significantly better for mitomycin-based than cisplatin-based treatment (10% vs 19%; P = .02). Severe hematologic toxicity was worse with mitomycin-based treatment (P < .001).

Conclusions  In this population of patients with anal canal carcinoma, cisplatin-based therapy failed to improve disease-free-survival compared with mitomycin-based therapy, but cisplatin-based therapy resulted in a significantly worse colostomy rate. These findings do not support the use of cisplatin in place of mitomycin in combination with fluorouracil and radiotherapy in the treatment of anal canal carcinoma.

Trial Registration  clinicaltrials.gov Identifier: NCT00003596

  相似文献   

84.
Minced tumor fragments were xenografted into subcutaneous tissue of the lateral thoracic regions of young adult, virgin female nude mice to study the effects of somatostatin analog SMS 201-995 on growth of estrogen-dependent (MCF-7) and estrogen-independent (BT-20) human breast carcinomas. When tumors became palpable (6 to 10 days), mice were assigned randomly to receive either SMS (4 to 50 micrograms) or acetate buffer (0.2 ml) subcutaneously twice a day. For MCF-7, mean tumor volume was significantly lower on day 20 and days 30 through 50 in SMS-treated mice than in controls (p less than 0.05), and tumor doubling time was increased from 13.2 to 19.0 days. Calculated growth increment was significantly lower with SMS than with buffer treatment (1.1 +/- 0.1 vs 1.9 +/- 0.2) (p less than 0.001). For BT-20, mean tumor volume of SMS-treated mice was slightly, but not significantly, lower than that of controls; however, calculated growth increment was significantly lower for SMS treatment (3.2 +/- 0.3 vs 3.9 +/- 0.4) (p +/- 0.001), and tumor doubling time was increased from 4.0 to 5.8 days. For MCF-7, flow cytometric DNA analysis of tumor biopsy samples demonstrated a reduced G2 + M phase with SMS treatment. We conclude that SMS slows the growth of both MCF-7 and BT-20 human breast cancer xenografts in nude mice and that SMS may be clinically useful in the management of patients with breast carcinoma.  相似文献   
85.
Anaesthetic and sedation techniques, complications and outcomes were reviewed in 176 children undergoing 184 interventional cardiologic procedures. Techniques included sedation only, and ketamine, inhalational or narcotic anaesthesia. Ketamine infusion was the technique most frequently used. Ketamine was associated with a higher incidence of respiratory complications (P < 0.05) than the other techniques. The higher incidence of hypercarbia (15.6 per cent), which did not affect outcome, may be attributable to the use of supplemental sedatives. The incidence of upper airway obstruction (7.8 per cent) was similar to that of previous studies. Vascular compromise resulted from the procedure in 33 patients, necessitating surgical correction in 16. Cardiac perforation occurred in four cases, causing one death. Pulmonary valve stenosis was most amenable to balloon dilatation and aortic valve stenosis least amenable. Ketamine was the anaesthetic agent preferred by cardiologists for use in the catheterisation suite when general anaesthesia was required. Vigilant monitoring by anaesthetic staff is necessary during the procedure, and avoidance of concomitant narcotics is recommended if a ketamine technique with spontaneous ventilation is used. Les techniques anesthésiques et de sédation ainsi que les complications et les issues ont été revues chez 176 enfants subissant 184 procedures cardiaques. Les techniques ont inctu soil la sédation seulement, soit l’anesthésie à la kétamine, aux agents d’inhalation ou aux narcotiques. La perfusion de kétamine était la technique la plus fréquemment utilisée. La ketamine était associée à une plus grande incidence de complication respiratoire (P < 0.05) comparativement aux autres techniques. La plus grande incidence d’hypercarbie (15.6 pour cent), n’ayant pas affecté l’issue, pourrait être attribuée à l’utilisation additionnelle de sédatifs. L’incidence d’obstruction des voies aériennes supérieures (7.8 pour cent) était similaire aux études préalables. Un problème vasculaire suite à la procédure fut observé chez 33 patients dont 16 ont requis une correction chirurgicale. Une perforation cardiaque est survenue dans quatre cas provoquant le décès d’un seul patient. La sténose de la valve pulmonaire était la procédure la plus susceptible d’être dilatée et la sténose de la valve aortique la moins susceptible. La kétamine était l’agent anesthésique préféré par les cardiologistes lors des cathétérisations quand une anesthésie générate était requise. Une surveillance vigilante par une équipe anesthésique fut nécessaire durant la procedure. Il faut aussi éviter l’administration de narcotiques si la kétamine est administrée en respiration spontanée.
Presented in part at the Canadian Anaesthetists’ Society annual meeting in Halifax, June 1988.  相似文献   
86.
BACKGROUND--We describe a patient with a subepidermal bullous skin disease associated with autoantibodies recognizing separate epitopes in 1 mol/L sodium chloride (NaCl) split skin. OBSERVATIONS--Direct immunofluorescence microscopy showed deposits of immunoglobulins and C3 in a continuous pattern in the patient's epidermal basement membrane zone. Direct immunoelectron microscopy demonstrated thick deposits of IgG overlying the lamina lucida and the lamina densa in a unique pattern. The patient had circulating IgG anti-basement membrane zone antibodies that bound both sides of 1 mol/L NaCl split skin, exhibited at least a fourfold-higher titer against the dermal side of this test substrate, and bound basal keratinocyte hemidesmosomes as well as focal sites along the superior portion of the lamina densa on indirect immunoelectron microscopy. Affinity purification of anti-basement membrane zone antibodies against epidermal or dermal strips of 1 mol/L NaCl split skin yielded IgG that only bound the side of split skin from which it was eluted. The patient's serum contained IgG that immunoprecipitated and immunoblotted the 230- and 170-kd bullous pemphigoid antigens. Affinity purification of patient antibody against bullous pemphigoid antigen immobilized on nitrocellulose paper yielded IgG that bound only the epidermal side of 1 mol/L NaCl split skin. The patient showed no evidence of reactivity against type VII collagen by direct immunoelectron microscopy, indirect immunoelectron microscopy, or immunoblot. CONCLUSIONS--This patient's bullous skin disease is associated with IgG anti-basement membrane zone antibodies with two specificities: one recognizing the bullous pemphigoid antigen in the epidermal side of 1 mol/L NaCl split skin, and another binding a distinct, yet presently unidentified, epitope in the superior aspect of the lamina densa.  相似文献   
87.
A patient with an anomaly of hair pattern development is described. Scalp hair follicles generally grow at a downward inclination to the scalp surface. Normal whorled patterns appear in the posteroparietal area. The patient described was noted to have a whorled hair pattern located over the right temporoparietal region, growing in a clockwise direction. The remainder of the scalp adopted the upward follicular growth pattern of the posterior portion of the whorl, directed toward the apical anatomic axis. A ridge of hair over the nape of the neck reversed direction, similar to hair growth on the Rhodesian Ridgeback dog, growing in a downward manner. The relationship of this new hair pattern to current theories of scalp hair pattern development is reviewed.  相似文献   
88.
BACKGROUND: To evaluate the use of high-density silicone oil (HDSO) as a tamponade agent for retinal detachment secondary to myopic macular hole. METHODS: 12 eyes of 12 patients with macular hole retinal detachment underwent pars plana vitrectomy, internal limiting membrane peeling and HDSO tamponade. No posturing was required postoperatively and HDSO was removed 3-4 months later. Outcome measures included macular hole closure and retinal attachment rates, best-corrected visual acuity (BCVA), and intraoperative and postoperative complications. RESULTS: The mean age of the patients was 67.8 years and the mean spherical equivalent refractive error was -13.4 diopters. After the removal of HDSO, 10 (83%) eyes had macular hole closure with retinal reattachment without any tamponade. One eye had retinal reattachment after re-operation and the other refused further surgery. At the last follow-up, the median BCVA improved from 20/800 to 20/600 (p = 0.046). A transient increase in intraocular pressure was observed in 5 (42%) eyes and one eye each developed mild oil emulsification and transient peripheral choroidal detachment. None of the eyes was found to have severe intraocular inflammation postoperatively. CONCLUSIONS: HDSO seemed to be an effective tamponade agent for myopic macular hole retinal detachment. Further prospective controlled studies seem warranted.  相似文献   
89.
In vitro experiments have indicated that in primary hyperparathyroidism (HPT) the hyperfunctioning glands have a set point error, i.e., they are not autonomous but regulate serum calcium around a hypercalcémie value. In contrast, parathyroid function is suppressed in patients with hypercalcemia of causes other than HPT (e.g., malignancy or sarcoidosis). The basal measurements of serum parathyroid hormone (PTH) levels, however, cannot, alone, separate with precision HPT from other causes of hypercalcemia.Lowering of calcium, in order to stimulate secretion of PTH, was, therefore, achieved by either infusion of Na2 EDTA (24 mg/kg per hr) for 1 hour, or intramuscular injection of 100 IU salmon calcitonin. All 35 patients with primary HPT displayed a significant increase of serum PTH concentrations, evaluated by a midregion/intact hormone assay, during the EDTA infusion, which lowered plasma ionized calcium by an average of 0.16 mmol/l. The injection with calcitonin reduced the calcium concentrations by 0.10 mmol/l after 8 hours and caused a rise in PTH in 80% of HPT patients. With both tests, the secretory response by PTH to the reduction of plasma calcium was generally evident while the patients were still hypercalcemic. In 32 patients with other causes for hypercalcemia, primarily malignancy and sarcoidosis, similar reductions of plasma ionized calcium were obtained. In contrast to the HPT patients, none of them raised their serum PTH values during the test. Thus, stimulation of PTH secretion by a moderate reduction of serum calcium considerably improves the differential diagnosis of hypercalcemia since a significant secretory response appears to be exclusive for HPT.
Resumen Experimentos in vitro han señalado que en el hiperparatiroidismo primario (HPT) las glándulas hiperfuncionantes tienen un error en su set point, o sea que no son autónomas sino que regulan el calcio sérico alrededor de un valor hipercalcémico. Por el contrario, la función paratiroidea es suprimida en pacientes con hipercalcemia de causa diferente de HPT (e.g., neoplasias malignas o sarcoidosis). Las mediciones basales de los nivelés séricos de hormona paratiroidea (PTH) de por sí no son capaces de diferenciar con precision entre el HPT y la hipercalcemia de otras causas.La disminución del nivel de calcio sérico, con el objeto de estimular secreciones de PTH, fue lograda con la infusión de Na2 EDTA (24 mg/Kg por hora) por 1 hora o la inyección i.m. de 100 UI de calcitonina de salmón.Todos los 35 pacientes con HPT primario exhibieron un aumento significativo de las concentraciones séricas de PTH, determinadas mediante la medición de la fraction media/intacta de PTH en el curso de la infusion de EDTA, la cual redujo el nivel plasmático de calcio ionizado en un promedio de 0.16 mmol/l. La inyección de calcitonina redujo las concentraciones de sérico en 0.10 mmol/l a las 8 horas y resultó en un aumento de la PTH en 80% de los pacientes con HPT. Con ambas pruebas la respuesta secretoria de PTH a la reducción del calcio plasmático generalmente apareció evidente aún mientras los pacientes se hallaban hipercalcémicos.En 32 pacientes con hipercalcemia de causa diferente, se lograron reducciones similares de la concentration plasmática del calcio ionizado. Por el contrario de lo observado en los patientes con HPT, ninguno demostró elevatión de sus niveles séricos de PTH en el curso de la prueba. Por consiguiente, el estímulo de la secretión de PTH mediante la reductión moderada de calcio sérico incrementa considerablemente la (ie501-01)acidad de establecer el diagnóstico diferencial de la hipercalcemia, puesto que una significativa respuesta secretoria parece ser caracteristíca exclusiva del HPT.

Résumé L'expérimentation in vitro a démontré que dans l'hyperparathyroïdisme (HPT), les glandes hyperactives ont un point mort erroné, c'est-à-dire qu'elles ne sont pas autonomes mais règlent la calcémie autour d'une valeur de référence déjà hypercalcémique. En revanche, la fonction parathyroîde est déprimée chez le patient dont l'hypercalcémie est due à une cause autre que l'HPT (cancer ou sarcoïdose par exemple). La mesure des niveaux de base de la parathormone (PTH), cependant, ne permet pas de distinguer l'hypercalcémie de l'HPT des autres causes d'hypercalcémie avec précision.Dans le but de stimuler la sécrétion de PTH, la calcémie était abaissée soit en perfusant les patients avec une solution de Na2 EDTA (24 mg/Kg) pendant une heure, soit par une injection intramusculaire de 100 U de calcitonine de saumon.Trente-cinq patients ayant un HPT primitif présentaient une augmentation significative des concentrations en PTH sérique, évaluée par l'étude immunologique de la portion moyenne intacte, pendant la perfusion d'EDTA. La portion de calcium plasmatique ionisée a été abaissée en moyenne de 0.16 mmol/l. L'injection de calcitonine a réduit la concentration en calcium par 0.10 mmol/l après huit heures et a provoqué une augmentation en PTH chez 80% des patients à HPT. Quel que soit le test, la réponse de PTH à la réduction de calcium plasmatique était généralement évidente alors que le patient était toujours hypercalcémique.Chez 32 autres patients ayant pour cause d'hypercalcémie cancer ou sarcoïdose, des réductions similaires en calcium plasmatique ionisé ont été obtenues. Aucun malade, contrairement aux patients HPT, n'a vu son niveau de PTH monter pendant le test. Ainsi, la stimulation de sécrétion de PTH par une réduction modérée de calcium sérique améliore considérablement le diagnostic différentiel des hypercalcémies puisque la réponse sécrétoire significative paraît être le fait exclusif des HPT.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.

Supported by the Swedish Medical Research Council.  相似文献   
90.
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