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1.
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated.  相似文献   
2.
The effects of 10% dietary xylitol supplementation in ovariectomized rats were studied on the degradation of bone organic and inorganic structures. The osseal concentrations of hydroxyproline, pyridinoline, and deoxypyridinoline were analyzed by high-performance liquid chromatography. Bone resorption was measured in [3H]tetracycline-prelabeled rats by urinary excretion of 3H, and by the amount of 3H preserved in bone. Bone trabeculation was measured by a computer image analyzer from sections stained by the method of von Kossa. The amount of collagen in bone organic fraction was lower in ovariectomized rats as compared with the sham-operated controls. This most likely is partly a consequence of an increased resorption, and partly a consequence of a higher proportion of immature periosteal bone in the ovariectomized animals, leading to a higher ratio of noncollagenous protein to collagen. The number of pyridinium crosslinks was lower in proportion, indicating no selective changes in the structure of collagen. Dietary xylitol significantly retarded the ovariectomy-associated decrease in the relative amount of collagen and the number of its mature crosslinks. Ovariectomy doubled the excretion of 3H and caused a significant decrease in the amount of 3H preserved in bone; both these changes were significantly retarded by the 10% dietary xylitol supplementation. Ovariectomy significantly decreased the volume of bone trabeculae, but this effect was also significantly inhibited by the xylitol supplementation in the diet. In conclusion, these findings suggest a dietary xylitol-induced normalizing effect on the rate of bone turnover in ovariectomized rats. Received: 12 February 1996 / Accepted: 20 August 1996  相似文献   
3.
HIV-associated wasting is defined as > or = 10% involuntary weight loss and includes declines in both lean and fat mass. This large (757 subjects), randomized, double-blind, placebo-controlled trial investigated the efficacy, safety, and tolerability of recombinant human growth hormone (rhGH) in 2 doses-0.1 mg/kg up to a maximum of 6 mg daily (DD) or alternate days (AD)-in the treatment of wasting and weight loss in highly active antiretroviral therapy (HAART)-treated HIV-infected subjects. The evaluable population for ergometry comprised 555 subjects, 87.6% of whom were receiving HAART. At 12 weeks, median maximum work output increased by 2.4 and 2.6 kJ in the AD and DD groups, respectively. The median treatment difference was 2.9 kJ for DD vs. placebo (P < 0.0001). Body weight increased by 2.2 and 2.9 kg in the AD and DD groups, respectively. Corresponding median treatment differences vs. placebo were 1.5 and 2.2 kg (P < 0.0001). Lean body mass (LBM), by bioelectric impedance spectroscopy, increased by 3.3 and 5.2 kg, respectively (P < 0.0001 vs. placebo; P = 0.0173 DD vs. AD), and fat mass, predominately truncal, decreased. Quality of life (QoL) improved significantly in both rhGH groups. Fluid-retention adverse effects and hyperglycemia were more common in the DD than in the AD group. No significant changes in HIV viral load or CD4 cell count occurred. In conclusion, over the 12-week course of therapy, rhGH, 0.1 mg/kg DD, was superior to placebo in improving physical function, body weight, body composition, and QoL and was superior to AD dosing in restoring LBM.  相似文献   
4.
Ovarian tumours obtained at laparotomy were histochemically examined for their local fibrinolytic activity, and simultaneous fibrin/fibrinogen degradation products (FDP) were determined in the serum. The fibrinolytic activity was confined mainly to vessels of both malignant and benign tumours. A very close correlation was demonstrated between the fibrinolytic activity and the vascularity of the sections. FDP were found in the serum in 13 of 14 patients with malignant tumours, but in none with benign tumours. The difference in occurrence of FDP in patients with malignant and benign tumours might be due to the invasive growth of the former with the entrance of thromboplastic substances, fibrinolytic activators or locally formed FDP into the bloodstream.  相似文献   
5.
The effects of 5, 10, and 20% dietary xylitol supplementations on the biomechanical properties, histological architecture, and the contents of collagen, pyridinoline, and deoxypyridinoline in long bones of rats were studied. Tibiae were used for the three-point bending test, and femurs were used for the torsion and loading test of the femoral neck. The 10 and 20% oral xylitol administrations caused a significant increase of tibial stress, femoral shear stress, and stress of the femoral neck as compared with the controls. Parallel, but not significant, effects were also seen in the 5% xylitol supplementation group. No significant differences in strain or Young's modulus of the tibiae were detected between the groups. An increased shear modulus of elasticity in femurs was detected in the 20% supplementation group as compared with the controls. The histomorphometrical data for the secondary spongiosa of the proximal tibia revealed that trabecular bone volume was significantly greater in all dietary xylitol supplementation groups as compared with the controls. The bone volume increased along with increasing xylitol content. No significant differences between the groups were detected concerning the amount of collagen per dry weight of organic matrix, the concentrations of pyridinoline or deoxypyridinoline in collagen, or the ratio of these crosslinks. This suggests no xylitol-dependent selective changes in these structures of bone collagen. In conclusion, dietary xylitol supplementation in rats improves the biomechanical properties of bone and increases the trabecular bone volume dose dependently. Received: 30 January 1997 / Accepted: 1 October 1998  相似文献   
6.
Incubated restrained and unrestrained extensor digitorum longus (EDL) muscles from adult non-growing mice were evaluated as a tool in non-steady state nutrition experiments. Energy state was determined by nucleotide determinations in muscles. Protein synthesis was estimated by the amount of L-[U-14C]phenylalanine incorporated into proteins, and protein balance was measured by tyrosine release from muscle proteins. Confluent cultured L6 rat muscle cells served as a reference system in steady state without hypoxia being sensitive to growth factors and regulatory peptides at physiologic concentrations. Irrespective of medium composition, incubated EDL muscles remained in negative protein balance, being unrelated to the resting tension of the incubated muscles. Energy-rich phosphates were not restored to normal levels during incubation, but protein synthesis was not attenuated by the decline in energy state. Fractional protein synthesis (0.05-0.15%/h) remained constant for up to 6 h of EDL incubation, and was comparable to protein synthesis in cultured confluent non-proliferating myocytes (0.20-0.30%/h) and to mixed leg muscles measured in vivo (0.10-0.20%/h). Protein synthesis in incubated EDL muscles reflected alterations in muscle peptide formation in vivo following either oral provision of food or parenteral injection of insulin. EDL muscles were sensitive to in vitro exposure to both insulin (60-125 microU/mL) and insulin-like growth factor 1 (IGF-1) (1000 ng/mL). The sensitivity to insulin seemed to be modified by the nutritional state (starved/fed) of the animals before sacrifice. Protein synthesis in EDL muscles was less responsive to serum-containing growth factors (IGF-1, epidermal growth factor [EGF], platelet-derived growth factor [PDGF]) compared to confluent L6 muscle cells, which probably reflected different receptor expression. Our results demonstrate that protein metabolism in incubated unrestrained mouse EDL muscles reflects in vivo protein metabolism.  相似文献   
7.
The influence of consumption of a lactic acid-fermented cereal gruel togwa with pH < or = 4 on the presence of faecal enteric bacteria such as campylobacter, enterohaemorrhagic Escherichia coli (EHEC:O157), enterotoxigenic Escherichia coli (ETEC), salmonella and shigella was evaluated. Under 5 years old healthy children listed in an ascending order of age were alternatively assigned and given either a lactic-acid fermented cereal gruel togwa (test diet) or an unfermented cereal gruel uji (control diet) once a day for 13 consecutive days. The presence of the enteropathogens was examined in rectal swabs collected from the children at baseline (before feeding session started), on days 7 and 13, and additionally 14 days (follow-up day) after the feeding session had stopped. The swabs were cultured on to different optimal media for respective enteropathogen and confirmed by standard microbiological and serological methods. Campylobacter spp. dominated among the enteropathogens (62% out of total) followed by Salmonella spp., ETEC and Shigella spp. Children with isolated enteropathogens in the togwa group was significantly reduced (P < 0.001) from 27.6% at baseline to 7.8, 8.2 and 12.7% on days 7, 13 and follow-up day, respectively. The effect was more pronounced in those children taking togwa > 6 times during the study period. In the control group, there was a slight decrease from 16.7% at baseline to 11.4% on day 7 and 8.1% on day 13. On the follow-up day, enteropathogens were found in 22.6% of the children, which was significantly higher than in those children taking togwa > 6 times. We conclude, that regular consumption of togwa with pH < or = 4, once a day, three times a week may help to control intestinal colonization with potential diarrhoea-causing pathogens in young children.  相似文献   
8.
9.
Background Different reasons influence the current low birth-rate and the postponement of the birth of the first child throughout Europe. The aim of this study was to explore how highly educated women and men in Sweden reflect on fertility and postponed parenthood.Methods We interviewed women (n = 22) and men (n = 18) who had started their professional careers and still had no children. Data were analysed with qualitative content analysis.Results Fertility was perceived as an unconsidered capacity, sometimes unpredictable, and different for women and men, but nevertheless taken for granted. The participants were of the opinion that fertility could be restored by assisted reproductive technologies or replaced by alternatives to a biological child. Postponed parenthood was described as an adaptation to societal changes and current discourses about parenthood as well as a consequence of a contemporary lifestyle with many competing priorities.Conclusion Highly educated young women and men in contemporary Sweden have competing priorities when planning and setting goals for their lives, and having children is one of them. They describe fertility as an imperceptible and retrievable capacity and postponed parenthood as a rational adaptation to changes in society. These findings suggest that increased information about the limitations of human reproduction is needed, but also that societal support for younger parents is of utmost importance.  相似文献   
10.
Surgery for fulminating colitis during pregnancy   总被引:2,自引:1,他引:2  
Two cases of fulminating colitis presenting during pregnancy are described. In both cases, resectional surgery was performed. In the first case, cesarean section was combined with subtotal colectomy and ileostomy during the 32nd week of gestation. In the second case, cesarean section was performed during the 33rd week of gestation and proctocolectomy in the puerperium. In both cases, histopathologic examination showed colitis more consistent with Crohn's disease. It is concluded that if fulminating colitis appears during pregnancy it should be treated in the same manner as in the nonpregnant state.  相似文献   
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