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31.
A case of deep-vein thrombosis is reported in a female patient with multibacillary leprosy who received pulses of dexamethasone and cyclophosphamide for recurrent ENL that had not responded to prednisone and thalidomide.  相似文献   
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Serotonin is suggested to regulate adult hippocampal neurogenesis, and previous studies with serotonin depletion reported either a decrease or no change in adult hippocampal progenitor proliferation. We have addressed the effects of serotonin depletion on distinct aspects of adult hippocampal neurogenesis, namely the proliferation, survival and terminal differentiation of hippocampal progenitors. We used the serotonin synthesis inhibitor p-chlorophenylalanine (PCPA) or the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) to deplete serotonin levels. 5,7-DHT selectively decreased hippocampal serotonin levels, while PCPA resulted in a significant decline in both serotonin and norepinephrine levels. We observed a robust decline in the proliferation and survival of adult hippocampal progenitors following PCPA treatment. This was supported by a decrease in the number of doublecortin-positive cells in the neurogenic niche in the hippocampus. In striking contrast, 5,7-DHT did not alter the proliferation or survival of adult hippocampal progenitors and did not alter the number of doublecortin-positive cells. The terminal differentiation of adult hippocampal progenitors was not altered by either PCPA or 5,7-DHT treatment. An acute increase in serotonin levels also did not influence adult hippocampal progenitor proliferation. These results suggest that selective serotonin depletion or an acute induction in serotonin levels does not regulate adult hippocampal neurogenesis, whereas treatment with PCPA that induces a decline in both serotonin and norepinephrine levels results in a significant decrease in adult hippocampal neurogenesis. Our results highlight the need for future studies to examine the role of other monoamines in both the effects of stress and antidepressants on adult hippocampal neurogenesis.  相似文献   
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p- Aminodiphenylamine (p-ADPA), an aromatic amine of wide industrial applications, also finds human exposure through hair dye preparations or via ingestion of a common food colouring metanil yellow. Acute and short-term toxicity studies in albino rats have been done following the biochemical markers, hematology and tissue histopathology. The acute LD50 value of p-ADPA is 0.847 g/kg body weight which qualifies for the 'moderately toxic' category. In short-term studies, animals were fed p-ADPA, mixed in routine laboratory diet at the concentrations of 0.0 (control), 0.1, 0.25, 0.5 and 0.75% (w/w), daily for 90 days. Feed intake and body weight gain in the highest dosed group were reduced. Hematological examinations exhibited moderate anemic conditions with decreased red blood cells, increased erythrocyte sedimentation rate and lowered packed cell volume suggesting normocytic normochromic anemia at 0.25% onward levels of p-ADPA intake. There was significant increase in the activities of acid/alkaline phosphatases and GOT/GPT in serum with simultaneous depletion from liver at the levels of 0.5 and 0.75% p-ADPA intake, suggesting biochemical lesions of the liver. Testicular LDH and hyaluronidase were lowered at 0.5 and 0.75% levels indicating partial arrest of spermatogenesis. These findings were supported histopathologically. The study warrants careful consideration on its exposure, industrially or through common food color or hair dye preparations.  相似文献   
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Papillon-Lefevre Syndrome   总被引:1,自引:0,他引:1  
Papillon-Lefevre syndrome in six Saudi children in the same family is described. The parents were unaffected, and parental consanguinity was present. Palmoplantar keratosis started at the age of 1 1/2 years. The loss of deciduous teeth was a consequence of juvenile periodontitis. All essential features of the syndrome were present in this series.  相似文献   
38.
The role of broiler eggs in the transmission of Campylobacter jejuni to broiler grow-out flocks was investigated. Six breeder flocks supplying broiler eggs to hatcheries were examined for cloacal carriage of C. jejuni. Of 240 birds tested, 178 (74%) were C. jejuni-positive. Eggs from these birds examined for C. jejuni penetration of the egg shell indicated that 185 of 187 were campylobacter-free. Eggs from breeder flocks of unknown C. jejuni status were also examined for C. jejuni shell penetration. C. jejuni was not isolated from 142 eggs examined. A further 193 hatchery eggs incubated and hatched in the laboratory were campylobacter-free. Six farms containing the progeny of C. jejuni-positive breeder flocks were monitored. Eight hundred and forty birds from 14 flocks in these grow-out farms were campylobacter-free during their 6-week grow-out period. Experimental egg-penetration studies indicated that C. jejuni transmission via the egg is not easily effected. Of 257 eggs surface-challenged with C. jejuni, 162 hatched; all were campylobacter-free. Of 167 eggs injected with C. jejuni, 12 hatched; 2 of these were colonized with C. jejuni. Our data do not support a role for vertical transmission of C. jejuni in commercial broiler production.  相似文献   
39.
Bone fracture healing is sensitive to the fixation stability. However, it is unclear which phases of healing are mechano‐sensitive and if mechanical stimulation is required throughout repair. In this study, a novel bone defect model, which isolates an experimental fracture from functional loading, was applied in sheep to investigate if stimulation limited to the early proliferative phase is sufficient for bone healing. An active fixator controlled motion in the fracture. Animals of the control group were unstimulated. In the physiological‐like group, 1 mm axial compressive movements were applied between day 5 and 21, thereafter the movements were decreased in weekly increments and stopped after 6 weeks. In the early stimulatory group, the movements were stopped after 3 weeks. The experimental fractures were evaluated with mechanical and micro‐computed tomography methods after 9 weeks healing. The callus strength of the stimulated fractures (physiological‐like and early stimulatory) was greater than the unstimulated control group. The control group was characterized by minimal external callus formation and a lack of bone bridging at 9 weeks. In contrast, the stimulated groups exhibited advanced healing with solid bone formation across the defect. This was confirmed quantitatively by a lower bone volume in the control group compared to the stimulated groups.The novel experimental model permits the application of a well‐defined load history to an experimental bone fracture. The poor healing observed in the control group is consistent with under‐stimulation. This study has shown early mechanical stimulation only is sufficient for a timely healing outcome. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1790–1796, 2018.
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40.
C.J. Brew  V. Rao  J. Shanker 《The Foot》2010,20(4):146-148
Isolated tuberculosis osteomyelitis affecting the foot is extremely rare. Symptoms are nonspecific and haematological investigations are often unhelpful making diagnosis difficult.We report the case of a 41-year-old female who presented with a 7-month history of a painful hindfoot following a minor ankle sprain. Inflammatory markers were mildly raised and initial radiographs showed only some mild narrowing of the talonavicular joint. MRI scanning suggested osteomyelitis centred over the talonavicular joint. Open biopsy confirmed areas of caseous necrosis but no acid-fast bacilli were seen. The final diagnosis was confirmed with culture of mycobacterium tuberculosis. A good recovery was seen following debridement and commencement of anti-tuberculosis chemotherapy.Unless an awareness of this condition exists, the diagnosis and therefore the appropriate treatment can often be delayed which may lead to significant consequences for the patient.  相似文献   
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