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21.
Long term chronic calorie restriction (CR) of adult nonhuman primates significantly reduces morbidity and increases median age of death. The present review is focused upon an ongoing study of sustained adult- onset calorie restriction, which has been underway for 15 years. Monkeys, initially calorie restricted at about 10 years of age, are now approximately 25 years old. The median life span of these restricted monkeys is increasing, now exceeding that of ad libitum (AL)-fed monkeys. In our laboratory, maximum life span for AL-fed monkeys appears to be about 40 years. Thus, whether CR can also increase maximal life span, as it does in rodents, cannot be determined for at least another 15 years. The earliest detectable positive benefit on morbidity in these monkeys was previously reported as the prevention of obesity. Current evidence, as reviewed here, suggests that much obesity- associated morbidity is also mitigated by sustained calorie restraint in nonhuman primates. Furthermore, probably because of the prevention of obesity, diabetes has also been prevented. Recent findings include the identification of extraordinary changes in the glycogen synthesis pathway, and on the phosphorylation of glycogen synthase in response to insulin. This calorie restriction-induced prevention of morbidity does not require excessive leanness, but is clearly present when body fat is within the normal range of 10 to 22%, and this is likely to be true in humans as well.   相似文献   
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Objective  To investigate the efficacy and safety of suction–curettage with a combination of two different cannulae for treatment of axillary osmidrosis and hyperhidrosis.
Design  Retrospective analysis of patients who underwent surgery from September 2004 to September 2006.
Setting  Outpatient clinic for hyperhidrosis at a university-affiliated hospital.
Subjects  Sixty-five patients who were treated for axillary malodor and hyperhidrosis.
Interventions  Patients were sequentially treated with Fatemi and Cassio cannulae.
Main outcome measures  Demographic data, severity data (assessment of malodor), degree of satisfaction, sweating, hair growth, scarring, recurrence and complications.
Results  Sixty of the 65 patients (96.9%) had excellent to fair results, and only 2 patients (3.1%) had poor results. Complications occurred in 4 patients (6.2%). Recurrence occurred in 3 patients (4.6%).
Conclusions  This simplified and inexpensive method resulted in a high success rate with low complications and high satisfaction with minimal scarring and rapid recovery.  相似文献   
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Aims. This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background. Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design. Systematic review. Methods. MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results. Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially‐available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions. There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy‐related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice. This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence‐based advice to their patients.  相似文献   
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The plasminogen activation system is one of the enzyme systems held responsible for bone and cartilage degradation in rheumatoid arthritis (RA). In this study, we evaluated the effect of tranexamic acid (TEA), an inhibitor of plasminogen activation, on urinary collagen cross-link excretion and radiological joint damage in rat adjuvant arthritis (AA) and on urinary collagen cross-link excretion in patients with RA. In the animal study, adjuvant arthritis was induced in male Lewis rats. From day 7 onward, high-dose TEA (500 mg/kg body weight, once daily) or placebo was administered orally. Study groups consisted of TEA-treated normal rats (C + TEA), placebo-treated normal rats (C + plac), AA rats treated with TEA (AA + TEA) or with placebo (AA + plac). To monitor joint destruction, urinary collagen cross-link excretion (pyridinoline, HP; deoxypyridinoline, LP) was measured by high-performance liquid chromatography at days 14 and 21. Radiological evaluation of joints was performed at day 21. In the patient study, TEA was administered to nine patients with RA as adjuvant medication (approximately 20 mg/kg body weight, three times daily) for 12 weeks. Urinary HP and LP excretion levels were measured before and during TEA treatment, and 4 weeks after the cessation of TEA treatment. In AA + TEA rats, a significant reduction of HP and a tendency towards a reduction of LP excretion were found compared with AA + plac rats (P < 0.05), at day 14, whereas the HP/LP ratio did not change. No difference was observed in HP, LP excretion, HP/LP ratio and radiological damage score between the TEA- and placebo-treated AA rats at day 21. In RA patients, a significant reduction of HP and LP excretion was found during the TEA treatment period (P < 0.05). After the cessation of TEA treatment, HP and LP excretion increased towards baseline levels. No effect on disease activity was observed. The plasmin antagonist TEA reduced the excretion of collagen pyridinoline cross-links in both experimental and rheumatoid arthritis. As such, this study not only supports the involvement of the plasminogen activation system in the destructive phase of arthritis, but also suggests a beneficial effect of therapeutic strategies directed against inhibition of matrix proteolysis.   相似文献   
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The origin of low-grade mucosa-associated lymphoid tissue (MALT)-type B- cell lymphoma is still unclear. Using a novel two-step procedure, we have sequenced the Ig VH genes expressed by cells from four patients with gastric low-grade MALT-type lymphoma. The nucleotide sequences of the complementarity determining region 3 (CDR3) of the genomic DNA were first amplified using consensus oligonucleotide primers, then sequenced. Based on the CDR3 sequence amplified from each MALT lymphoma, individual tumor-specific primers were synthesized and used directly in the polymerase chain reaction (PCR) to analyze the sequences of their Ig heavy-chain variable region. When compared with the germ-line sequence, many nucleotide substitutions, mainly in the CDRs, were found in the variable gene sequences of the four MALT lymphomas. The mutations showed a high replacement-to-silent ratio and were distributed in a way which suggested that the tumor cells had been positively selected through their antigen receptor. Our findings indicate that the MALT-type lymphoma B cells are hypermutated postgerminal center lymphocytes that have undergone antigen selection.  相似文献   
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Hemoglobinopathies have a protective role in malaria that appears to be related to alterations in red blood cell (RBC) properties. Thalassemic RBCs infected with Plasmodium falciparum showed greatly reduced cytoadherence and rosetting properties as well as impaired growth and multiplication. A significant decrease in the levels of falciparum antigens associated with the membrane of infected beta-thalassemic RBCs was observed at trophozoite/schizont stage, but not young ring stage. This reduction was shown when a cytoadherence inhibitory monoclonal antibody, but not a noninhibitory pooled immune serum, was used. These observations suggest that protection against malaria in thalassemia is caused by both reduced parasitemias and altered adherence properties of the infected thalassemic RBCs that promote enhanced clearance of the parasite from the circulation.  相似文献   
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