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31.
The pharmacokinetic behaviour of the 131-iodine-labelled title compound 3 * and its metabolites in mice was investigated. A two phase, 1st order elimination profile was observed. The second phase is very slow leaving about 35% of radioactivity in the mice even 100h after i.v. injection, because of high affinity to liver and spleen, caused by strong binding of oligoamines to phospholipids of liver and blood cell membranes. The blood-brain-barrier is not passed. No deep compartments were observed. The doses necessary for antithrombotic effects in vivo were calculated from the blood levels to be 20.5–39.7 μmol/kg for a time interval of 1–6 h after administration.  相似文献   
32.
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to 116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied in patients with renal transplants. Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996  相似文献   
33.
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment.  相似文献   
34.
One hundred and sixty-four patients admitted to a psychogeriatric unit were given a combination of four different cognitive tests: the Mini Mental State Examination (MMSE), the Abbreviated Mental Test Score, The Felix Post Unit Score and the compilation of tests recommended by the MRC Alzheimer's Disease Workshop. The tests were compared with respect to their ability to sort accurately cases of dementia and depression, and the effects of age and education on test score and misclassification rate with diagnosis controlled for. The MMSE had a very high misclassification rate for the poorly educated and depressed group. The logistical discriminant functional analysis selected only eight items as the best discriminators between organic/ functional or dementia/depression groups. Only one of these eight was not either a memory or orientation test. The value of simply adding up tests of different aspects of cognitive function in dementia assessment or screening is questioned.  相似文献   
35.
36.
In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO‐blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100%(TiO‐blasted) vs 95.3%(machined), P =0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 tvues of implant after 2 years of loading, 0.04 (0.82) mm, P >0.30.  相似文献   
37.
Mechanism of the CuCl/O2-mediated Oxygenation of Naphtholes The mechanism of the oxygenation of 1- and 2-naphthole derivatives in the system $\left[ {\mathop {\rm C}\limits^{+} \mathop {\rm u}\limits^{1} {\rm L}_4 } \right]^{+} + {\rm O}_2 \rightleftharpoons \left[ {\mathop {\rm C}\limits^{+} \mathop {\rm u}\limits^2 {\rm L}_3 {\rm O}_2^{^.} } \right]^{+} + {\rm L}$ depending on solvent (L) and temp., is studied. It was possible to distinguish between reactions via the radical ion pair type (L = CH3CN) and hydrogen abstraction via free radicals (L = CH3OH). There is a marked difference between the oxygen transfer to the naphthole derivatives and the oxygenation of 2, 6-di-tert.-butylphenol ( 6 ), which does not depend characteristically on L and temp.  相似文献   
38.
In a recent study we described an increase of elastic tissue fibres in blood vessel walls of placental stem villi during pre-eclampsia when compared to uncomplicated pregnancies. Furthermore, the thickness of these blood vessel walls was enhanced in pre-eclampsia. Since it is known that elastic tissue fibres increase in systemic hypertension, it may be assumed that the enhancement of elastic tissue fibres in placental stem villi during pre-eclampsia may be induced by the hypertension. To get further insight into this assumption, we examined the amount of elastic tissue fibres in stem villus blood vessels of placentae of pregnancies complicated by intrauterine growth retardation (isolated IUGR, fourteen cases), a disease without hypertension of the mother and such with pre-eclampsia and concomitant IUGR (IUGR+PE, nine cases). Each study group was compared with uncomplicated pregnancies (twenty-six cases). Unfixed cryostat serial sections were processed for conventional orcein staining and for the demonstration of alpha-actin-immunoreactivity. The intensity of orcein staining of stem villus blood vessel walls was evaluated by a semiquantitative score method. Significant lower intensities of orcein staining were calculated for blood vessel walls of placentae of isolated IUGR (P=0.0007) and IUGR+PE (P=0.0039) when compared to uncomplicated pregnancies each. Additionally, the blood vessel wall thickness of stem villi of isolated IUGR (P=0.0081) and IUGR+PE (P=0.0007) was significantly reduced. In comparison to the above mentioned investigation, our results show that, in contrast to isolated pre-eclampsia, elastic tissue fibres are decreased during pregnancies complicated by IUGR, independently of the occurrence of concomitant pre-eclampsia when compared to uncomplicated pregnancies. From our studies it may be considered that the increase of elastic tissue fibres in placentae of patients with isolated pre-eclampsia may be induced by systemic hypertension. Furthermore, our study underline arguments that IUGR may be an independent disease of the fetus.  相似文献   
39.
Taste buds are chemosensory endorgans consisting of modified epithelial cells. Fish and other vertebrates use their taste bud cells to sample potential food, either selecting or rejecting substances according to their edibility. The adult gustatory system in fish has been studied thoroughly, including regeneration experiments. Taste buds occur in the epithelia of the lips, the mouth cavity, the oropharyngeal cavity, and also in the skin of the barbels, the head, and sometimes even all over the body surface. Despite its importance for feeding, little is known about the ontogeny of the fish taste system. We examined the development of taste buds in the zebrafish on the light microscopical and the scanning and transmission electron microscopical levels. Taste buds develop later than the olfactory organ and the solitary chemosensory cells, two other chemosensory systems in aquatic vertebrates. The first few taste bud primordia are visible within the epithelia of lips and gill arches 3 to 4 days after fertilization, and the first few taste buds with open receptor areas appear on the lips and simultaneously on the gill arches 4-5 days after fertilization, which coincides with the onset of feeding. Taste buds in the mouth cavity, on the head, and on the barbels are formed later in development. As seen in other fish, zebrafish taste buds contain elongate dark and light cells, termed according to their electron density. Dark cells with a cell apex of many short microvilli appear first, followed by the light cells with one large microvillus. In addition, the zebrafish has a third fusiform cell type, which appears last. This cell type is low in electron density and has a brush-like apical ending with several small microvilli. This cell type has not been described previously. Furthermore, in zebrafish, the ontogenetic processes of taste bud formation differ from regenerative processes described in the literature.  相似文献   
40.
Summary Different regions of human aorta and of other human arteries obtained at autopsy were analyzed with regard to their topography and to the different stages of arteriosclerosis. Material was studied by immunocytochemical techniques with antibodies specific for either desmin (D) or for vimentin (V), the two types of intermediate filament proteins present in vascular smooth muscle cells. In normal arteries endothelial cells as well as the adjacent intimal cells were D–V+. In the media D+V+ as well as D–V+ cells were present, with the relative numbers of each cell type dependent on the particular blood vessel. When cells in arteriosclerotic plaques at different stages of development were examined an occasional plaque showed cells of the D+V+ type. In the majority of plaques however the cells were V– D+. In plaques where severe ulceration and necrotic material was present D–V+ cells were found at the border of the lesion: foam cells when they could be identified appeared to be D–V+.  相似文献   
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