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11.
S. Örn P. L. Andersson L. Förlin M. Tysklind L. Norrgren 《Archives of environmental contamination and toxicology》1998,35(1):52-57
Zebrafish (Danio rerio) were orally exposed to a mixture of 20 PCBs in three different dose levels (0.008, 0.08, and 0.4 μg of each congener per
gram of freeze-dried chironomids). Generally, the PCBs accumulated in a dose-related manner. After 13 weeks of exposure body,
liver, and ovary weights, as well as the liver and ovary somatic index, were significantly lower in exposed groups. In addition,
the PCB mixture was an effective inducer of hepatic EROD activity. The reproduction study performed with exposed females and
unexposed males after 9 weeks revealed that median survival time for larvae was only 7.7 days in the high-dose group as compared
with 14 days in controls. Furthermore, egg production was reduced in all three groups exposed. No differences in hatching
frequency or median hatching time were recorded. Histologically, females in both the intermediate and high-dose groups contained
a reduced number of mature oocytes. The present study demonstrates that the potency of the mixture of selected PCBs induces
hepatic EROD activity and has a clearly negative effect on zebrafish reproduction.
Received: 7 May 1997/Accepted: 29 November 1997 相似文献
12.
Gülin Vural Mustafa Ünlü Tamer Atasever Izlem Özur Ayşegül Özdemir Nahide Gökçora 《European journal of nuclear medicine and molecular imaging》1997,24(3):312-315
Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series. 相似文献
13.
HERMAN TOURNAYE RONNY JANSSENS PAUL DEVROEY RK VAN STEIRTEGHEM 《International journal of andrology》1994,17(1):1-8
In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment. 相似文献
14.
S. Palaoglu A. Sungur A. Atasever S. Ruacan S. Akalin T. Özgen A. Erbengi 《Acta neurochirurgica》1994,128(1-4):1-7
Summary The effects of pineal gland, an endocrine organ known to affect the physiology of various organs and systems including the hypothalamo-hypophyseal axis, on the morphological characteristics of target organs were investigated in rats after pinealectomy and foetal pineal gland transplantation to a subpial cortical area close to the pinealectomized region.It was demonstrated that weight gain was significantly slower in pinealectomized male rats (p<0.01); pituitary gland weight was lower in the pinealectomized group (p<0.01) and transplantation had no effect on the weight of this organ; weight of adrenal gland and testis were lower after pinealectomy (p<0.01) but restored back to control levels after transplantation; the mitotic activity in seminiferous tubules increased with pinealectomy and returned back to control indexes after transplantation.Research on hypothalamic catecholaminergic content revealed a diminished histofluorescence in pinealectomized rats which showed a potentiated restoration after transplantation.The innervation of the pineal gland was studied by anterograde and retrograde injections of Wheat Germ Agglutinin Horse Radish Peroxidase from superior cervical ganglion and pineal gland, respectively. It was demonstrated that cell bodies were traced both at the transplanted tissue and hypothalamus.In view of these data, the multifunctional and a probable high level homeostatic harmony regulator essence of pineal gland is discussed.The paper has been awarded the 1993 Upjohn prize for Neurosurgical Research of the European Association of Neurosurgical Societies. 相似文献
15.
Danuta Wasserman Christer HellstrÖm Jerzy Wasserman Olof Beck Eva Andersson Marie Åsberg 《Archives of Suicide Research》1997,3(3):153-169
The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function. 相似文献
16.
Acute subdural hematoma: Outcome and outcome prediction 总被引:3,自引:0,他引:3
R. Kemal Koç M.D. Hidayet Akdemir I. Suat Öktem Mehmet Meral Ahmet Menkü 《Neurosurgical review》1997,20(4):239-244
Patients with traumatic acute subdural hematoma were studied to determine the factors influencing outcome.Between January 1986 and August 1995, we collected 113 patients who underwent craniotomy for traumatic acute subdural hematoma. The relationship between initial clinical signs and the outcome 3 months after admission was studied retrospectively.Functional recovery was achieved in 38% of patients and the mortality was 60%. 91% of patients with a high Glasgow Coma Scale (GCS) score (9–15) and 23% of patients with a low GCS score (3–8) achieved functional recovery. All of 14 patients with a GCS score of 3 died. The mortality of patients with GCS scores of 4 and 5 was 95% to 75%, respectively. Patients over 61 years old had a mortality of 73% compared to 64% mortality for those aged 21–40 years. 97% of patients with bilateral unreactive pupil and 81% of patients with unilateral unreactive pupil died. The mortality rates of associated intracranial lesions were 91% in intracerebral hematoma, 87% in subarachnoid hemorrhage, 75% in contusion.Time from injury to surgical evacuation and type of surgical intervention did not affect mortality. Age and associated intracranial lesions were related to outcome. Severity of injury and pupillary response were the most important factors for predicting outcome. 相似文献
17.
Fatoş Yalçınkaya Necmiye Tümer Nilgün Çakar Nuray Özkaya 《Pediatric nephrology (Berlin, Germany)》1997,11(3):350-352
Hypertension is one of the most important complications of erythropoietin (rHuEPO) therapy in dialysis patients. In this
study, the effect of two different dosage regiments of subcutaneous rHuEPO on blood pressure [BP] was evaluated in 20 anemic
children on continuous ambulatory peritoneal dialysis (CAPD). Patients were randomized to receive rHuEPO 50 U/kg, either once
a week (group 1, 50 U/kg per week) or three times a week (group 2, 150 U/kg per week). At the beginning of the study, 8 patients
in group 1 and 8 patients in group 2 were on antihypertensive therapy. In group 1, the hematocrit increased gradually and
significantly from 18.98%±1.79% to 30.1%±1.62% after 6 months, while in group 2 it rapidly increased from 19.53%±1.86% to
32.4%±1.11% after 3 months. A significant increase in the mean arterial BP was observed in group 2. Antihypertensive therapy
had to be increased in all of the 8 previously hypertensive patients and had to be initiated in 1 of the 2 originally normotensive
patients in the same group. None of the patients in group 1 required a change in antihypertensive medication. We conclude
that during treatment with rHuEPO pre-existing hypertension and the dose of rHuEPO are the most important risk factors for
the development or worsening of hypertension in children on CAPD, and gradual elevation of hematocrit by low-dose rHuEPO avoids
the development of severe hypertension.
Received December 11, 1995; received in revised form September 16, 1996; accepted September 19, 1996 相似文献
18.
Bülent Gül Sezer Kulaçoglnu Dr. Muammer Yükse Handan Dogan Ali Ihsan Ökten 《Neurosurgical review》1997,20(1):59-61
Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from olfactory mucosa, often with intracranial extension.A case report of the youngest victim in the literature (2-year-old boy) is presented. 相似文献
19.
20.
V. JNSSON H. D. SCHRDER W. TROJABORG T. STAEHELIN JENSEN E. HIPPE M. MRK HANSEN 《Journal of internal medicine》1992,232(2):185-191
A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens. 相似文献