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121.
F Prats M Porta Serra H Yazbeck R Herrera J M Gassó 《Gaceta sanitaria / S.E.S.P.A.S》1990,4(20):179-183
OBJECTIVES: To estimate the prevalence of antibodies to human immunodeficiency virus (HIV), antibodies to hepatitis B core antigen (anti-HBc), hepatitis B surface antigen (HBsAg), and antibodies to delta virus (anti-DV). DESIGN: Cross-sectional (prevalence) study. A non-proportional (stratified by length of stay) random sample of 20% of admitted patients was selected. CLINICAL SETTING: The Hospital Psiquiátrico Nuestra Se?ora de Montserrat (Sant Boi de Llobregat, Barcelona, Spain) admits about 670 patients in its short-term, rehabilitation (mid-term) and long-term wards. SUBJECTS: 139 patients were selected: 91% were males, mean age was 55 years, and 10% belonged to an HIV risk group; mean length of hospitalization since last discharge was 13 years. MEASUREMENTS: Blood samples were drawn in October, 1988. Anti-HBc, HBsAg and anti-DV were determined by competitive enzyme immunoassay (EIA). Anti-HIV-1 were determined by sandwich EIA; negativity of results with high absorbency but below the cut-off point was confirmed by Western blot. RESULTS: None of the sampled patients had circulating anti-HIV-1 antibodies. Four cases showing high absorbency (below the "cut-off" point) were ruled out by Western-blot. Overall, the prevalence of anti-HBc was 52.8% (54.4% in long-term wards, 35.0% in mid-term wards, and 13.8% in short-term wards). The prevalence of HBsAg was 2.3%, of anti-DV 1.5%, and of HDAg 0%. CONCLUSIONS: Prevalence of anti-HIV is null in the studied institution. Current efforts to prevent HIV infection must continue; a hepatitis B vaccination program is highly warranted among patients and professionals of the studied hospital. 相似文献
122.
Summary The level of selenium in blood serum was determined in 33 patients with breast cancer, 13 women with verified mastopathy, and 43 healthy subjects from the Zagreb area. In the second and third quartiles the values of selenium obtained from sick subjects (41–58µg/L) and healthy subjects (73–89µg/L) differed significantly (P < 0.001). In the group of subjects with mastopathy, serum selenium in the same way ranged from 67–76µg/L and did not differ significantly from the group of healthy women, but differed significantly from the patients with breast cancer (P < 0.001).Such a result leads to the conclusion that determination of selenium in the blood could be used as a non-invasive diagnostic parameter in clinical assessment of malignant breast disease. 相似文献
123.
High-dose thiotepa with autologous bone marrow rescue is a new and promising treatment modality in several kinds of solid tumors. We used this regimen in a pediatric patient who had the third recurrence of his malignant oligodendroglioma of brain that developed during 8 in 1 chemotherapy. We achieved complete response after a total dose of 1125 mg/m2 of intravenous thiotepa. Good penetration into the CNS renders thiotepa potentially useful for chemosensitive brain tumors, and one course of high-dose thiotepa can be administered with acceptable toxicity by utilizing autologous bone marrow rescue. 相似文献
124.
Baixauli F Vicent V Baixauli E Serra V Sánchez-Alepuz E Gómez V Martos F 《Clinical orthopaedics and related research》1999,(361):205-215
A 120 degrees blade plate reinforced by a strut is introduced for the treatment of unstable intertrochanteric and proximal subtrochanteric fractures. Mechanical tests showed that the strength of this reinforced resistance device was 11,758 N. This strength is two and three times greater than that of the Gamma nail and sliding hip screw, respectively, and five times greater with the strut than without it. Three hundred fifty-eight patients older than 60 years of age were treated with this method between 1987 and 1991 (mean followup, 16 months). Six months after surgery the fracture had united in 82% of the patients who were walking without aid or using only a cane. Weightbearing began when the patient's general overall condition allowed such activity (average, 5 days; mode, 3 days). A chi squared test showed no difference regarding the results between stable and unstable fractures. Intraoperative and postoperative complication rates were 3% and 7.1%, respectively. The failure of fixation rate was 5.4%. Mechanical tests and clinical results showed that immediate weightbearing can be allowed in all types of intertrochanteric fractures. This reinforced device is effective in treating unstable intertrochanteric fractures and is especially indicated for the most unstable types (Evans' Grades 4 and 5). 相似文献
125.
Glial cell line-derived neurotrophic factor-like immunoreactivity in human trigeminal ganglion and nucleus 总被引:2,自引:0,他引:2
Glial cell line-derived neurotrophic factor (GDNF) is shown by immunohistochemistry in human trigeminal sensory system from 22 weeks of gestation to adulthood. In the trigeminal ganglion, a distinct subpopulation of GDNF-positive neurones is observed, which amounts to about 15% at early pre-term and adult ages and peaks to around 30% at perinatal ages. Labelled neurones are mostly small- and medium-sized. Occasionally, Schwann and satellite cells are stained. GDNF/substance P (SP) and GDNF/calcitonin gene-related peptide (CGRP) double stained neurones occur at all ages examined, whereas GDNF/trkA coexistence can be observed in pre- and full-term newborns only. Centrally, GDNF-immunostained fibers and terminal-like structures are mainly restricted to the spinal trigeminal nucleus, where they are codistributed with SP and CGRP. In the subnucleus caudalis, positive neurones can also be observed both in the superficial laminae and in the magnocellular part, with higher frequency in adults. These results suggest that GDNF may play a functional role in human trigeminal primary sensory neurones throughout life and provide indication for its possible involvement in the regulation of pain-related neuronal circuits in human trigeminal sensory system. 相似文献
126.
127.
128.
M Serra P Madau M F Chessa M Caddeo E Sanna G Trapani M Franco G Liso R H Purdy M L Barbaccia G Biggio 《British journal of pharmacology》1999,127(1):177-187
Selective activation of peripheral benzodiazepine receptors (PBRs) in adrenal cells and brain oligodendrocytes promotes steroidogenesis. Three 2-phenyl-imidazo[1,2-a]pyridine derivatives (CB 34, CB 50 and CB 54) have now been investigated with regard to their selectivity for PBRs and their ability to stimulate central and peripheral steroidogenesis in rats. The three CB compounds (10(-10)-10(-4) M) potently inhibited the binding of the PBR ligand [3H]-PK 11195 to brain and ovary membranes in vitro, without substantially affecting [3H]-flunitrazepam binding to central benzodiazepine receptors. These compounds (10(-7)-10(-4) M) also had little or no marked effects on GABA-evoked Cl- currents in voltage-clamped Xenopus oocytes expressing human alpha1beta2gamma2S GABA(A) receptors. In addition, they failed to affect ligands binding to GABA(B), D1/D2 dopamine, muscarinic acetylcholine, N-methyl-D-aspartic acid and opiate receptors. Intraperitoneal administration of CB compounds (3-50 mg kg(-1)) induced a dose-dependent increase in the concentrations of neuroactive steroids in plasma and brain. The brain concentrations of pregnenolone, progesterone, allopregnanolone and allotetrahydrodeoxycorticosterone (THDOC) showed maximal increases in 96+/-3, 126+/-14, 110+/-12 and 70+/-13% above control, respectively, 30 to 60 min after injection of CB 34 (25 mg kg(-1)). CB 34 also increased the brain concentrations of neuroactive steroids in adrenalectomized-orchiectomized rats, although to a lesser extent than in sham-operated animals, suggesting that CB compounds stimulate brain steroidogenesis independently of their effects on peripheral tissues. The increase in brain and plasma neurosteroid content induced by CB 34 was associated with a marked anticonflict effect in the Vogel test. Our results indicate that the three CB compounds tested are specific and potent agonists at peripheral benzodiazepine receptors, and that they stimulate steroidogenesis in both the brain and periphery. 相似文献
129.
A. Dolei C. Serra A. Biolchini S. Curreli P. Marongiu E. Gomes F. Ameglio 《Perspectives in Drug Discovery and Design》1996,5(1):93-102
Summary HIV-1 is a polytropic virus that, apart from hematopoietic cells, can replicate in several cells from solid tissues. Virus yields vary widely, closely resembling differences in HIV binding to the cells; the latter phenomenon appears mainly related to the extent of CD4 expression, even though other molecules have been implied in virus-cell interactions, the expression of which on the cell membrane can be modulated by several stimuli. During the course of HIV replication, a series of cytokines is produced and released in parallel to virus growth, particularly IL-6 and TNF-. In fact, exposure of fibroblasts or epithelial cells to these HIV-in-duced cytokines causes an increase of CD4 expression, HIV adsorption to uninfected cells, and release of infectious virions by infected cells. In cells exposed to interferon-, IL-6 and TNF- allow the virus to bypass interferon inhibition of virus release. The fact that HIV-1 adsorption and spread can be mediated by HIV-induced cytokines may be relevant in AIDS pathogenesis, accelerating virus transmission both within the organ and to infiltrating cells, activating a self-maintaining mechanism of infection. 相似文献
130.
Antero Aitio Sinikka Valkonen Helena Kivistö Erkki Yrjänheikki 《International archives of occupational and environmental health》1983,53(2):139-147
Summary The activities of three plasma lysosomal hydrolases, -galactosidase, -glucuronidase and -N-acetylglucosaminidase, were studied in 20 workers exposed to metallic mercury vapor in a chlorine alkali plant and in 10 nonexposed referents. The urinary excretion and blood levels of mercury were determined on the day of study, and the history of mercury exposure was reviewed from the records of mercury concentrations in urine and blood over periods of up to 133 months. The average levels of -N-acetylglucosaminidase and -glucuronidase were higher in the plasma of exposed workers, but the difference was not significant. No significant positive correlation was seen between lyosomal enzyme activities and cumulative long-term exposure to mercury. It is concluded that measurement of plasma lysosomal hydrolase-activities is not of great value in the biological monitoring of workers exposed to low concentrations of metallic mercury vapor.In line with published data, the concentration of mercury showed a clearcut diurnal variation in nonexposed persons, persons currently exposed and persons with a history of past exposure. The excretion rate of mercury remained constant throughout the day. 相似文献