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11.
Among 33 patients with endocrine pancreatic tumors due to multiple endocrine neoplasia type 1 (MEN-1), 19 (58%) patients had hypergastrinemia, 7 (21%) patients had hyperinsulinism, and 7 (21%) patients had clinically non-functioning lesions. At least one gross tumor was found in all patients undergoing pancreatic surgery, including those with negative localization studies prior to operation. The patients also had additional macroscopic tumors as well as numerous microadenomas, and the lesions frequently were positive for immunostaining with multiple hormones, mainly pancreatic polypeptide, insulin, glucagon, and somatostatin. Duodenal endocrine lesions were found in 4 of 5 investigated patients and stained with gastrin and somatostatin antibodies. Distal, mainly subtotal pancreatic resection, was performed in 18 patients, eventually combined with caput tumor enucleation or duodenotomy, while a few patients underwent only tumor enucleation or a Whipple procedure. The long-erm outcome of operation was most favorable in patients with hyperinsulinism; only 1 patient had clinical recurrence. Patients with hypergastrinemia experienced only transitory lowering of serum gastrin values after pancreatic surgery and 47% of them had or developed metastases. Such tumor spread was seen in 57% of the patients with non-functioning lesions. Nine patients died from progressive tumor disease during follow-up. Consistent with previous studies, we found that surgery is indicated in MEN-1 patients with hyperinsulinism even if a lesion is not visualized by radiology. In addition, these indications should be extended to also include patients with only biochemical markers of disease, including elevations of gastrin, as these indicate the presence of gross tumors. This strategy should be applied especially in patients with aggressive family histories to possibly reduce the risk of malignant tumor progression.
Resumen Entre 33 individuos con tumores pancréaticos endocrinos como componente del síndrome de neoplasia endocrina múltiple tipo 1 (NEM-1), 19 pacientes (58%) tenían hipergastrinemia, 7 (21%) hiperinsulinismo y 7 (21%) lesiones clínicas no funcionantes. En la totalidad de los pacientes sometidos a cirugía pancreática fue hallado por lo menos un tumor, incluso en aquellos con examenes de localización negativos anteriores a la operación. Estos pacientes también albergaban tumores macroscópicos, así como numerosos microadenomas; con frecuencia las lesiones demostraron inmunocoloración con diferentes hormonas, principalmente polipéptido, insulina, glucagón y somatostatina. Se encontraron lesiones endocrinas duodenales en 4 de cada 5 pacientes investigados, las cuales colorearon con gastrina y anticuerpos a la somatostatina. Se practicó resección pancreática distal (principalmente resección subtotal) en 18 pacientes, eventualmente combinada con enucleación del tumor (cuando éste se hallaba ubicado en la cabeza del páncreas) o duodenectomía; solamente unos pocos pacientes fueron sometidos a simple enucleación del tumor o al procedimiento de Whipple. El resultado a largo plazo fue más favorable en los pacientes con hiperinsulinismo, puesto que sólo uno presentó recurrencia clínica. Los pacientes con hipergastrinemia exhibieron apenas una disminución transitoria de los valores de gastrina sérica luego de la cirugía pancreática. Cuarenta y siete por ciento del conjunto tuvo o desarrolló metástasis, en tanto que la extensión local del tumor se presentó en 57% de los casos con lesiones no funcionantes. Nueve pacientes murieron por progresión de la neoplasia en el curso del seguimiento. En acuerdo con sugerencias previas, se considero quo la cirugía está indicada en pacientes con NEM-1 e hiperinsulinismo, aún en los casos en que no se visualiza radiológicamente la lesión, pero que la indicación puede ser ampliada para incluir también pacientes con sólo marcadores bioquímicos, tales como niveles elevados de gastrina, indicativos de la presencia de tumores macroscópicos. Esta estrategia debe ser aplicada principalmente en aquellos pacientes con historia familiar agresiva, con lo cual tal vez se reduce el riesgo de progesión maligna del tumor.

Résumé Parmi 33 patients ayant une tumeur pancréatique endocrine due à une néoplasie endocrine multiple de type 1 (MEN-1), 19 (58%) avaient une hypergastrinémie, 7 (21%) un hyperinsulinisme et 7 (21%) une lésion cliniquement muette. On a mis en évidence au minimum une grosse tumeur chez tous les patients, y compris chez ceux dont les examens préopératoires de dépistage tumoral étaient négatifs. Les patients étaient également porteurs de tumeurs macroscopiques et de nombreux microadénomes. Les lésions montraient souvent un immunomarquage positif pour de multiples hormones, principalement le polypeptide pancréatique, l'insuline, le glucagon et la somatostatine. Des lésions endocrines duodénales furent retrouvées chez 4 des 5 patients explorés; elles montraient un immunomarquage avec les anticorps angigastrine et anti-somatostatine. Une résection pancréatique distale, le plus souvent subtotale, a été réalisée chez 18 patients. Elle était éventuellement complétée par une énucléation tmorale de la tête ou par une duodénotomie. Peu de patients ont bénéficié d'une simple énucléation ou d'une intervention de Whipple. L'évolution postopératoire à long terme a été plus favorable en cas d'insulinome puisque seul un patient a eu une récidive clinique. Les patients atteints de gastrinome n'ont présenté que transitoirement une diminution des taux sériques de gastrine après la chirurgie pancréatique. Quarante sept pour cent de ces patients avaient ou ont développé des métastases contre 57% des patients porteurs de lésions sans traduction clinique. Neuf patients sont décédés en raison de l'extension tumorale au cours du suivi. Conformément à des suggestions antérieures, la chirurgie semble indiquée chez les patients atteints de MEN-1 avec hyperinsulinisme même si la radiologie ne visualise pas de lésion. Mais cette indication peut être élargie aux patients dont seuls les paramètres biologiques sont en faveur d'une grosse tumeur (dont l'hypergastrinémie). Cette stratégie pourrait convenir particulièrement aux patients ayant des antécédents familiaux importants; elle permettrait peut-être de réduire le risque d'extension tumorale.


Presented at the International Association of Endocrine Surgeons in Stockholm, Sweden, August, 1991.  相似文献   
12.
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.  相似文献   
13.

Background  

Some studies have found that lower parity and higher or lower social class (depending on the study) are associated with increased risks of childhood acute lymphoblastic leukaemia (ALL). Such findings have led to suggestions that infection could play a role in the causation of this disease. An earlier New Zealand study found a protective effect of parental marriage on the risk of childhood ALL, and studies elsewhere have reported increased risks in relation to older parental ages. This study aimed to assess whether lower parity, lower social class, unmarried status and older parental ages increase the risk of childhood ALL (primarily). These variables were also assessed in relation to the risks of childhood acute non-lymphoblastic leukaemia, non-Hodgkin's lymphomas and Hodgkin's disease.  相似文献   
14.
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers.  相似文献   
15.
16.
Surface-active phospholipid as the lubricating component of lubricin   总被引:5,自引:0,他引:5  
To resolve the apparent conflict between a lubricating glycoprotein, 'lubricin', as the active ingredient in synovial fluid (SF) and surface- active phospholipid (SAPL) present in SF (and adsorbed to articular cartilage) as the boundary lubricant reducing friction to such low physiological levels, lubricin was isolated from bovine SF following the original procedure of Swann et al. (Arthritis Rheum 1981;24:22-30). Analysis of the lipid extract by thin-layer chromatography and phosphorus determination demonstrated a phospholipid component of 11.1 +/- 1.7% (N = 5) which corresponds very closely to the 9.2-13.0% of lubricin which had hitherto remained unidentified and which has previously been shown to be transferable to the articular surface to impart lubrication. These results would appear to resolve any theoretical conflict in that lubricin is, indeed, an active ingredient within SF. Yet, as a large water-soluble molecule, it really functions as a carrier for the highly insoluble SAPL which it deposits on the articular surface as the oligolamellar layer visualized in previous studies. However, it is this deposited SAPL, rather than lubricin, which actually lubricates.   相似文献   
17.
目的分析影响大学生饮酒模式的因素,针对饮酒教育及酒精政策提出建议。方法采用整群抽样方法,选择来自北京和郑州的530名大学生完成有效问卷调查。采用 Epidata 录入数据,SAS 12.0和 R 2.7.2进行数据描述和分析。结果74.5%的大学生在过去1年内饮过酒,啤酒是饮酒者的主要选择(85.9%),餐馆和家里是饮酒比较频繁的场所,饮用酒多来自同学/朋友及家庭成员提供,25.3%饮酒者并无特别原因饮酒,各有约1/5的饮酒者是出于社交目的或喜欢饮酒的感觉。认为“饮酒有助于社交暠或“饮酒促进交流暠者、父母及同学/朋友饮酒者、来自农村地区或小城镇者及吸烟者更容易发生饮酒行为(均 P 〈0.05),男生大学生、规律饮酒者更容易遭遇强迫劝酒场面、更易发生醉酒(均 P 〈0.05)。超过一半饮酒者出现酒后脸红、肌肉软弱无力等生理反应,饮酒对被调查大学生产生的社会心理影响依次是记忆丧失(23.9%)、宿醉(14.6%)、做了后悔的事(低于10%)等。结论目前大学生仍保持着一种低风险饮酒模式。大学生饮酒教育应提供关于饮酒利弊的科学信息,使其对饮酒保持一种现实的期望。应制定针对性酒精政策和教育鼓励和支持低风险且满足社交功能的饮酒模式,控制高风险饮酒模式。  相似文献   
18.
BACKGROUND: Type 1 gastric carcinoids are associated with hypergastrinaemia and chronic atrophic gastritis, type 2 occur in patients with multiple endocrine neoplasia type 1 combined with Zollinger-Ellison syndrome, and type 3 lack any relation to hypergastrinaemia. Type 1 tumours are usually benign whereas type 3 are highly malignant. AIMS: To identify possible tumour markers in patients with gastric carcinoids. PATIENTS/METHOD: Nine patients with type 1, one with type 2, and five with type 3 were evaluated with regard to symptoms, hormone profile, and prognosis. RESULTS: Plasma chromogranin A was increased in all patients but was higher (p < 0.01) in those with type 3 than those with type 1 carcinoids. All patients with type 3 carcinoids died from metastatic disease, but none of the type 1 patients died as a result of their tumours. One type 1 patient with a solitary liver metastasis received interferon alpha and octreotide treatment. Nine months later, the metastasis was no longer detectable. She is still alive eight years after diagnosis, without recurrent disease. This represents the only reported case of foregut carcinoid with an unresectable liver metastasis that seems to be have been cured by biotherapy. CONCLUSIONS: Plasma chromogranin A appears to be a valuable tumour marker for all types of gastric carcinoid. Combination therapy with interferon alpha and octreotide may be beneficial in patients with metastasising type 1 gastric carcinoids.  相似文献   
19.
The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases).  相似文献   
20.
We have evaluated survival and tumor-related symptoms in the presence of mesenteric lymph node and liver metastases in relation to surgical procedures in 314 patients (148 women, mean age at diagnosis 61 years; 249 with liver metastases) treated for midgut carcinoid tumors. Of the operated patients, 46% presented with severe abdominal pain and intestinal obstruction and were operated on before the diagnosis. Medical treatment (somatostatin analogs, interferon-a) was initiated in 67% and 86%, respectively. Surgical attempts included small intestine or ileocecal/right-sided colon resection with excision of mesenteric lymph node metastases. Most of the patients (n = 286) had mesenteric lymph node metastases; 33% of them had unresectable mesenteric lymph node metastases and underwent surgery without mesenteric dissection. Patients who underwent resection for the primary tumor had a longer survival than those with no resection (median survival 7.4 vs. 4.0 years; p <0.01). Patients who underwent successful excision of mesenteric metastases had a significantly longer survival than those with remaining lymph node metastases. Patients operated on for a primary tumor but with remaining lymph nodes but no liver metastases and who subsequently received interferon and somatostatin analog treatment had a median survival of 7.4 years. Resection of the primary tumor and the mesenteric lymph node metastases led to a significant reduction in tumor-related symptoms. Surgery to remove the primary intestinal tumor including mesenteric lymph node metastases is supported by the present results, even in the presence of liver metastases. Liver metastases and significant preoperative weight loss are identified as major negative prognostic factors for survival.  相似文献   
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