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11.
The transdermal and oral administration of estrogens for one year were compared with respect to the effects on lipid metabolism. Eighty-one postmenopausal women (1.5-3 years after menopause) were randomly divided into three groups. The first two groups received sequential estrogen treatment with either transdermal estradiol (Estraderm TTS, Ciba Geigy; 50 μg/day; 24 women) or 0.625 mg/day conjugated estrogens (Premarin, Wyeth; 20 subjects), respectively. In both groups medroxyprogesterone (10 mg/day per os) was added for 12 days of each cycle. Thirty-five subjects served as control group without therapy. No significant changes in the lipid profile was observed in control subjects after 1 year of follow-up. Serum triglycerides decreased significantly (-10.9 ± 26% S.D.; P < 0.05) in transdermal treated women, whereas it slightly rose in oral estrogen group. Comparable significant decreases in total and low density lipoprotein (LDL) cholesterol (mean range -6.5/-18.0%) were observed in women on estrogen replacement therapy. High density lipoprotein (HDL) cholesterol significantly diminished in transdermal estradiol group, but it rose slightly in the oral estrogen group. Thus the fraction of HDL cholesterol over LDL cholesterol did not change in the transdermal group whereas it significantly rose in subjects treated with oral estrogens. It remains to be established to what extent these differences on lipid metabolism are relevant for the prevention of cardiovascular diseases.  相似文献   
12.
Immunoreactivity for the tumour suppressor gene product p53 is commonly found in many different human malignancies and few premalignant lesions. Data on cervical neoplasms, however, are still lacking. We retrospectively investigated p53 immunoreactivity in 92 lesions of the uterine cervix, including 44 cases of chronic cervicitis, 29 squamous intraepithelial lesions (SILs), and 19 invasive carcinomas. p53 immunoreactivity confined to the basal cell layer, was detected in 74 per cent of cases showing chronic cervicitis and in all cases with low-grade SILs. Conversely, suprabasal and/or diffuse p53 immunoreactivity was exclusively demonstrated in 25 per cent of high-grade SILs and in 74 per cent of invasive carcinomas. The results of this investigation document a high prevalence of p53-immunoreactive malignant tumours of the uterine cervix. In high-grade SILs, p53-immunoreactive cells paralleled the height of involvement by dysplastic changes within the squamous epithelium. A prolonged half-life of the protein is the most likely explanation for the occurrence of p53 immunoreactivity in neoplastic cells. The unexpected finding of p53-immunoreactive cells in inflammatory lesions, though possibly related to an increased proliferation rate of the basal cell compartment, requires further study and underlines the need for a careful approach to p53 immunocytochemistry.  相似文献   
13.
Surgical treatment of portal hypertension in schistosomiasis   总被引:3,自引:0,他引:3  
Patients with mansonic schistosomiasis and portal hypertension are usually young, with good liver functional reserve, huge splenomegaly, and hypersplenism detectable only by alterations seen in laboratory tests. Patients who are not operated on do not develop portosystemic encephalopathy (PSE). Angiographic alterations are characteristic and totally different from those observed in patients with liver atrophy or cirrhosis. Digestive tract hemorrhage is the most severe complication. The patient with schistosomiasis is, therefore, a good model for the study of the consequences caused by the surgical treatment of portal hypertension. The evaluation, however, of results published in the literature regarding schistosomiasis is practically impossible. In a review of 130 publications referring to 4,516 surgically treated patients, the absence of prospective or retrospective studies with adequate controls was observed, and only 3.2% of the patients were followed for 5 years. According to available data, a total of 29 different surgical techniques has been employed, 81.6% of which are represented by simple splenectomy, esophagogastric devascularization (EGDS), and splenorenal shunt (SRS). Splenectomy was the surgical procedure showing the highest rate of recurrent hemorrhage (54.3%), and the portocaval shunt had the highest PSE incidence (60%). Portosystemic encephalopathy incidence after SRS was 29%. Thus, in view of a lack of objective information, in 1977 our group started a prospective, randomized study comparing the results of the surgical procedures most widely used in our country: selective portal decompression (SPD), EGDS, and SRS. The randomization was interrupted after 94 patients had been operated on (32 SRS, 30 SPD, and 32 EGDS) because of a highly significant PSE incidence in the SRS group. Preliminary results as of January, 1984, refer to an average follow-up period of 53 months (minimum 29, maximum 77 months). In the SRS group, the late mortality rate was 18.7%, and the incidence of PSE was 31.2%. Among the patients included in this group, 18.7% had arterial hypertension. In the SPD group, late mortality occurred in 10% of the cases, and PSE in 13.3%, while a mild hyperbilirubinemia was seen in 43.3% of patients. Recurrent hemorrhage and ascites had an approximately similar incidence in the 3 groups.
Resumen Los pacientes con esquistosomiasis mansónica e hipertensión portal generalmente son jóvenes con buena reserva funcional hepática, enorme esplenomegalia e hipersplenismo detectable solamente por las pruebas de laboratorio. Los pacientes nó operados no desarrollan encefalopatia portosistémica (EPS). Los cambios angiográficos son característicos y totalmente diferentes de los que se presentan en pacientes con cirrosis y atrofia hepática. La complicación más grave es la hemorragia digestiva. Por consiguiente, el paciente con esquistosomiasis es un buen modelo para el estudio de las consecuencias que se derivan del tratamiento quirúrgico de la hipertensión portal. Sinembargo, la evaluación de los resultados en la esquistosomiasis que han sido publicados en la literatura es prácticamente imposible. En una revisión de 130 publicaciones relativas a 4516 pacientes operados, se pudo comprobar ausencia de estudios prospectivos o retrospectivos con controles adecuados, y apenas el 3.2% de los casos fué seguido por 5 años. De acuerdo con los datos disponibles, se empleó un total de 29 técnicas quirúrgicas diferentes, 81.6% de los cuales estuvo representado por simple esplenectomía, devascularización esofagogástrica (DEG) y shunt espleno-renal (SER). La esplenectomía fué el procedimiento quirúrgico que tuvo la más alta incidencia de hemorragia recurrente (54.3%) y el shunt portacava la más alta incidencia de EPS (60%). La incidencia de EPS después de SER fué de 29%.Por consiguiente, en vista de la ausencia de información objetiva, nuestro grupo inición en 1977 un estudio prospectivo y aleatorizado para comparar los resultados de los procedimientos quirúrgicos mayormente utilizados en nuestro país: descompresión portal selectiva (DPS), DEG y SER. La aleatorización fué interrumpida después de haber operado los primeros 94 pacientes (32 SER, 30 DPS y 32 DEG) debido a una muy significativa incidencia de la EPS en el grupo con SER. Los resultados preliminares (enero de 1984) se refieren a un período promedio de seguimiento de 53 meses (mínimo 29, máximo 77 meses). En el grupo de SER la mortalidad tardía fué de 18.7% y la incidencia de EPS fué de 31.2%.El 18.7% de los pacientes incluidos en este grupo exhibió hipertensión arterial. En el grupo de DPS la mortalidad tardía fué de 10% y la incidencia de EPS de 13.3%; se observó hiperbilirrubinemia leve en 43.3% de los pacientes. La incidencia de hemorragia recurrente y de ascitis fué aproximadamente igual en los tres grupos.

Résumé Les malades qui accusent une hypertension portale d'origine bilharzienne sont généralement jeunes. Leurs fonctions hépatiques sont bonnes mais ils présentent une splénomégalie très importante et une hypersplénisme qui se manifeste seulement par des altérations des tests biologiques. Lorsqu'ils ne sont pas opérés ils ne présentent pas de manifestations d'encéphalopathie. Les caractères angiographiques sont très particuliers et totalement différents de ceux qui sont observés chez les sujets dont le foie est atrophié ou cirrhotique. L'hémorragie digestive représente la complication la plus sévère. Le malade atteint de bilharziose hépatique est par conséquent un bon modèle d'étude des conséquences provoquées par le traitement chirurgical de l'hypertension portale. Cependant les résultats du traitement publiés dans la littérature sont ininterprétables. Dans une revue de 130 publications concernant 4516 opérations, l'absence d'études prospectives ou rétrospectives bénéficiant d'un contrôle de qualité a été constatée, 3,2% seulement des malades ayant été suivis pendant 5 ans. En tenant compte des données disponibles 29 techniques chirurgicales ont été employées, 81,6% desquelles sont repésentées par les opérations suivantes: splénectomie, devascularisation et anastomose spléno-rénale. La splénectomie a été suivie du taux le plus élevé de récidive hémorragique (54,3%) et l'anastomose portocave du taux le plus important d'encéphalopathie (60%), l'anastomose spléno-rénale n'étant suivie d'encéphalopathie que dans 29% des cas. En raison du défaut d'information objective notre équipe a entrepris en 1977 une étude prospective faite selon la méthode du choix au hasard des 3 techniques chirurgicales les plus employées au Brésil: l'anastomose spléno-rénale, la décompression portale sélective et la dévascularisation. L'étude fut interrompue alors que 94 malades avaient été opérés (32 anastomose spléno-rénales, 30 décompressions portales sélectives et 32 dévascularisations oesophagogastriques) en raison du taux particulièrement élevé de l'encéphalopathie postopératoire. Les résultats de cette étude menée jusqu'en janvier 1984 répondent à une période postopératoire moyenne de 53 mois (minimum 29, maximum 77 mois). Dans le groupe traité par anastomose spléno-rénale le taux de la mortalité tardive fut de 18,7% et celui de l'encéphalopathie de 31,2%. Parmi les malades de ce groupe, 18,7% présentaient une hypertension artérielle. Dans le groupe traité par décompression portale selective le taux de la mortalité tardive fut de 10%, celui de l'encéphalopathie de 13,3%, cependant qu'une hyperbilirubinémie fut constatée chez 43,3% de ces opères. La récidive hémorragique et l'ascite atteignent un taux très voisin pour les trois opérations.
  相似文献   
14.
In peritoneal dialysis (PD), a cloudy dialysate is an alarming finding. Bacterial peritonitis is the most common cause, however, atypical infections and non‐infectious causes must be considered. A 46‐year‐old man presented with asthenia, paraesthesia, foamy urine and hypertension. Laboratory testing revealed severe azotaemia, anaemia, hyperkalaemia and nephrotic‐range proteinuria. Haemodialysis was started through a central venous catheter. Later, due to patient preference, a Tenckhoff catheter was inserted. Conversion to PD occurred 3 weeks later, during hospitalization for a presumed central line infection. A month later, the patient was hospitalized for neutropenic fever. He was diagnosed an acute parvovirus infection and was discharged under isoniazid for latent tuberculosis. Four months later, the patient presented with fever and a cloudy effluent. Peritoneal fluid (PF) cytology was suggestive of infectious peritonitis, but the symptoms persisted despite antibiotic therapy. Bacterial and mycological cultures were negative. No neoplastic cells were detected. Mycobacterium tuberculosis eventually grew in PF cultures, despite previous negative molecular tests. Directed therapy was then initiated with excellent response. Thus, facing a cloudy effluent, one must consider multiple aetiologies. Diagnosis of peritoneal tuberculosis is hampered by the lack of highly sensitive and specific exams. Here, diagnosis was only possible due to positive mycobacterial cultures.  相似文献   
15.
Background: Recent evidence indicates that an index of binocular activity may be found in some properties of steady-state visual evoked potentials (VEPs), such as amplitude facilitation and phase shortening. We evaluated binocular interactions with steady-state VEPs in normal subjects as well as in patients with concomitant strabismus and defective binocular vision. Methods: Steady-state (8-Hz) VEPs to counterphased sinusoidal gratings (1.2 c/deg spatial frequency) of low contrast (3.2%) were recorded in 19 esotropic patients and in 18 age-matched controls. Patients had either anomalous retinal correspondence (ARC, n =10) or suppression (n=9) in casual seeing conditions (striated glasses). In all subjects, both binocular and monocular VEPs displayed a major component at twice the stimulation frequency (second harmonic), whose amplitude and phase were measured. A binocular interaction index was obtained by comparing binocular VEPs (BVEPs) with the sum (vectorial) of the two monocular VEPs (SMVEPs). Results: In normal subjects, BVEPs were larger in amplitude than SMVEPs (facilitation), and shortened in latency (phase). On average, both ARC and suppression patients displayed loss in amplitude facilitation and absence of phase shortening. However, 50% of ARC patients showed clear VEP facilitation. In both ARC and suppression patients, the amplitude ratio BVEP/SMVEP was negatively correlated with the amount of the angle of deviation. Conclusion: These results suggest that losses in amplitude facilitation and phase shortening of binocular steady-state VEPs reflect abnormal binocular interactions associated with different forms of sensorial adaptation in concomitant strabismus.  相似文献   
16.
Osteoporosis is a common finding in Turner's syndrome. To test the hypothesis that calcitonin deficiency may contribute to bone mineral loss in Turner's syndrome, we studied basal and calcium-stimulated (2 mg/kg body weight in 5 min) levels of total calcitonin, extractable calcitonin and katacalcin in 15 girls with Turner's syndrome and osteoporosis. Fifteen age-matched healthy girls were studied as controls. Both basal calcitonin (total and extractable) and katacalcin values were not significantly different in patients with Turner's syndrome in comparison with those of the controls. The calcium stimulation test showed a similar "C" cell secretory reserve in both groups. The calculation of delta CT/delta iCa of total and extractable calcitonin and delta KC/delta iCa, which accounts for individual variations in serum ionized calcium increases, did not show any significant difference between girls with Turner's syndrome and controls. We conclude that calcitonin deficiency is not a causative factor of osteoporosis in girls with Turner's syndrome and that in this syndrome long-life estrogen deficiency does not impair "C" cell secretory activity.  相似文献   
17.
We measured parathyroid hormone levels in pregnant and nonpregnant women and at 1, 2 and 5 days of life in healthy term neonates and in hypocalcemic preterm infants using a new immunoradiometric assay which measures only biologically active intact parathyroid hormone and by a mid-molecule parathyroid hormone radioimmunoassay. During pregnancy intact and mid-molecule parathyroid hormone levels did not show any modification and were not different from parathyroid hormone levels of nonpregnant age-matched controls. Serum calcium and phosphorus levels did not vary during each trimester of pregnancy. In cord serum intact and mid-molecule parathyroid hormone values were low in both term and preterm infants. In term neonates intact and mid-molecule parathyroid hormone levels peaked on day 1; in preterm infants intact parathyroid hormone levels peaked on day 1 while mid-molecule parathyroid hormone values peaked on day 2. Intact parathyroid hormone levels showed a more marked increase in preterm (19-fold) than in term neonates (7.5-fold) on day 1. Our data do not confirm the previously reported "physiologic" hyperparathyroidism in pregnancy. Moreover we found a normal parathyroid gland responsiveness to decreasing serum calcium levels in the first days of life in term and preterm infants. Our results suggest that measurement of intact parathyroid hormone 1-84 by immunoradiometric assay in the first days of life is a more sensitive index of parathyroid gland secretory function than the measurement of middle or carboxyl-terminal parathyroid hormone fragments allowing the detection of the dynamic changes of parathyroid hormone which occur in hypocalcemic preterm infants.  相似文献   
18.
The present study was designed to investigate the role of nitric oxide (NO) on the acquisition of a recognition memory task in the rat. For this purpose, the effects on memory exerted by pre-training administration of the NO synthase inhibitor L-NAME (N(omega)-nitro-L-arginine methyl ester) and the NO donor molsidomine (N-[ethoxycarbonyl]-3-[4-morpholinosydnomine]) were assessed by using the object recognition task, a working memory paradigm based on the differential exploration of a new and familiar object. In a first dose-response study, it was found that L-NAME (10, 30, and 60 mg kg(-1), i.p.) at 30 but not at 10 mg kg(-1) disrupted animals performance, whereas the dose of 60 mg kg(-1) induced side effects. Molsidomine (2 and 4 mg kg(-1), i.p.) at 4 but not at 2 mg kg(-1), antagonized the L-NAME-induced performance deficits. These results indicate that NO is involved in the acquisition of a recognition memory task.  相似文献   
19.
20.
To evaluate the effect of central precocious puberty (CPP) and its treatment with gonadotropin-releasing hormone (GnRH) analogues on final height and peak bone mass (PBM), we measured lumbar bone mineral density (BMD) in 23 girls at final height. Patients were distributed in two groups. Group 1: 14 patients with progressive CPP were treated with GnRH analogues; seven patients received buserelin (1600 μg/daily), subsequently switched to depot triptorelin (60 μg/kg/26–28 days); seven patients were treated with depot triptorelin (60 μg/kg/26–28 days); mean age of treatment was 6.2 years (range 2.7–7.8 years); the treatment was discontinued at the mean age of 10.1 years (range 8.7–11.3 years); final height was reached at the mean age 13.4 years (range 12.0–14.9 years). Group 2: 9 patients (mean age 6.5 years, range 4.8–7.7 years) with a slowly progressing variant of CPP were followed without treatment; final height was reached at the mean␣age␣13.6 years (range 12.5–14.8 years). Lumbar BMD (L2-L4 by dual energy X-ray␣absorptiometry) was measured in all patients at final height. In group 1, final height␣(158.9 ± 5.4 cm) was significantly greater than the pre-treatment predicted height (153.5 ± 7.2 cm, P < 0.001), but significantly lower than mid-parental height (163.2 ± 6.2 cm, P < 0.005). Subdividing the girls of group 1 according to the bone age at discontinuation of therapy (i.e. ≤11.5 years, n = 5, or ≥12.0 years, n = 9), the former patients had a final height significantly higher than the latter (163.7 ± 3.9 cm vs 156.5 ± 4.6 cm, P < 0.02). In group 2, final height (161.8 ± 4.6 cm) was similar to the pre-treatment predicted height (163.1 ± 6.2 cm, P = NS) and was not significantly different from mid-parental height (161.0 ± 5.9 cm). BMD values (group 1: 1.11 ± 0.14 g/cm2, group 2: 1.22 ± 0.08 g/cm2) were not significantly different from those of a control group (1.18 ± 0.10 g/cm2; n = 20, age 16.3–20.5 years) and the patients' mothers (group 1: 1.16 ± 0.07 g/cm2, n = 11, age 32.9–45.1 years; group 2: 1.20 ± 0.08 g/cm2, n = 7, age 33.5–46.5 years). In group 1, the girls who stopped therapy at a bone age ≤11.5 years had significantly higher BMD (1.22 ± 0.10 g/cm2) compared to those who discontinued therapy at a bone age ≥12.0 years (1.04 ± 0.12 g/cm2, P < 0.05). Conclusion In girls with progressive CPP, long-term treatment with GnRH analogues improves final height. A subset of patients with CPP does not require treatment because good statural outcome (slowly progressing variant). In CPP, the abnormal onset of puberty and the long-term GnRH analogue treatment do not impair the achievement of PBM. In GnRH treated patients, the discontinuation of therapy at an appropriate bone age for pubertal onset may improve both final height and PBM. Received: 5 June 1997 / Accepted in revised form 21 November 1997  相似文献   
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