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41.
42.
Despite the potential utility of calcium supplementation and the availability of many calcium supplements in the market, there are few data concerning the absorbability of different calcium salts in different conditions. We have compared the acute metabolic responses following oral administration of calcium citrate (CC) or calcium gluconolactate and carbonate (CGC) given to 20 healthy perimenopausal women (aged 48–55 years). Ten women received two effervescent tablets of CC (each containing 500 mg of calcium) and 10 women received two effervescent tablets of CGC (each containing 500 mg of calcium). Before and on an hourly basis for 6 hours, serum total and ionized calcium, phosphate, and immunoreactive parathyroid hormone (iPTH) were measured. Urinary calcium and creatinine were also measured. Both calcium salts induced significant increase in serum total and ionized calcium and in urinary calcium excretion; they also significantly reduced circulating levels of iPTH. The analysis of ionized calcium and iPTH response curves to CC and CGC administration revealed a significantly greater bioavailability of CC compared with CGC. Our data suggest that CC could be prefered to CGC for its characteristics of absorbability and bioavailability.  相似文献   
43.
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray (PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro). Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat) into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7 nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan (3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii) the close relationship between glutamate and vasopressin in the central blood pressure regulation. Received: 1 April 1997 / Accepted: 2 February 1998  相似文献   
44.
Athletes comprise a unique population with special needs for the management and treatment of eating disorders. Prevention of these disorders also requires special approaches and strategies. Common attitudes, beliefs, and practices in athletics believed to be related to pressures to diet or to engage in pathogenic weight loss methods are discussed. Strategies for educating athletes and sport management personnel regarding issues related to eating disorders are proposed. Additionally, changes in the athletic environment designed to reduce the risk of eating disorders developing are recommended.  相似文献   
45.
Cystic neoplasms of the pancreas are rare lesions. Following the Compagno-Oertel classification, we differentiated serous microcystic adenomas (SMA) from mucinous macrocystic adenomas/adenocarcinomas (MMA). The former are benign tumors with slow growth, composed by innumerable small and tiny cysts with central calcifications, resulting in a "honeycomb" pattern. They have a mixed US structure while CT densitometric values reflect a mixture of connective tissue and proteinaceous fluid. Postcontrast enhancement is frequently seen. MMA are potential (adenoma) or frankly (adenocarcinoma) malignant tumors. They appear as multilocular cystic masses containing septa and/or papillary bulges, with thickened walls. Both US and CT demonstrate their predominantly cystic character, and the eventual presence of excrescences. We report a series of 23 cases (6 SMA, 17 MMA) of cystic neoplasms of the pancreas studied during the past five years. A correct diagnosis of SMA was possible in all 6 cases, while MMA was correctly diagnosed in 17 out of 18 cases. There were no false negatives, and 1 false positive. All differential diagnoses are also discussed.  相似文献   
46.
Summary The efficacy of intranasally administered neostigmine was tested in 22 patients with generalized myasthenia gravis (MG). Topical therapy to the highly vascularized oropharynx proved to be quickly effective in 5–15 min both clinically and electrophysiologically. Twenty-eight MG patients were then recruited from different centres and their morning doses of oral pyridostigmine were substituted with intranasal neostigmine over a period of 2 or 3 weeks. Intranasal neostigmine proved to be equally efficacious in this regimen. No side-effect was noted even in 4 patients treated in this way for 1 year. Intranasal administration of anti-acetylcholinesterase may be very beneficial: (1) for patients with irregular absorption of oral doses; (2) early in the morning and every time a fast and temporary effect is needed; (3) in bulbar impairment and emergencies, in which a handy atomizer may be life-saving.Presented in part at the XIV World Congress of Neurology, New Delhi, 22–27 October 1989  相似文献   
47.
Summary An epidemiological survey of hereditary ataxias and paraplegias was conducted in Molise, a region of Italy (335, 211 inhabitants on 1 January 1989). Total prevalence was 7.5 x 10–5 inhabitants (95% confidence limits 4.8–11.1). There were 7 patients with Friedreich's disease, 5 with early onset cerebellar ataxia with retained tendon reflexes, 4 with ataxia-telangiectasia, 9 with hereditary spastic paraplegias (2 autosomal dominant and 7 autosomal recessive cases). There was no patient with autosomal dominant cerebellar ataxia.  相似文献   
48.
Spectral karyotyping of prostate cell lines LNCaP, DU145, PC3, and 22RV demonstrated structural chromosome rearrangements involving the distal long arm of chromosome 4. In all but 22RV, these are nonreciprocal translocations between chromosomes 4 and 10. In 22RV, an apparently reciprocal t(2q;4q) is seen. Fluorescence in situ hybridization analysis of the chromosome 4 translocation breakpoints demonstrated that deletions were associated with all of the translocations, resulting in a net loss of chromosome material. Overlapping deletions in 4q28 approximately 34 were seen in LNCap, DU145, and 22RV, which defined an approximately 4.5-megabase pair common region of deletion. The deletion in PC3 was more proximal on 4q, involving the 4q21 approximately q26 region. A meta analysis of high-resolution definition of losses of chromosome material from published studies demonstrates that loss of 4q material may occur in at least 50% of primary tumors. This analysis defines a series of genes in the critical 4q region, which is potentially associated with prostate tumor development.  相似文献   
49.
Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.  相似文献   
50.
Radioprotective potential of ginseng   总被引:5,自引:0,他引:5  
A majority of potential radioprotective synthetic compounds have demonstrated limited clinical application owing to their inherent toxicity, and thus, the seeking of naturally occurring herbal products, such as ginseng, for their radioprotective capability has become an attractive alternative. In general, ginseng refers to the roots of the species of the genus Panax. As a medicinal herb, ginseng has been widely used in traditional Chinese medicine for its wide spectrum of medicinal effects, such as tonic, immunomodulatory, antimutagenic, adaptogenic and antiaging activities. Many of its medicinal effects are attributed to the triterpene glycosides known as ginsenosides (saponins). This review addresses the issue of the radioprotective effects of ginseng on mammalian cells both in vitro and in vivo. Results indicate that the water-soluble extract of whole ginseng appears to give a better protection against radiation-induced DNA damage than does the isolated ginsenoside fractions. Since free radicals play an important role in radiation-induced damage, the underlying radioprotective mechanism of ginseng could be linked, either directly or indirectly, to its antioxidative capability by the scavenging free radicals responsible for DNA damage. In addition, ginseng's radioprotective potential may also be related to its immunomodulating capabilities. Ginseng is a natural product with worldwide distribution, and in addition to its antitumor properties, ginseng appears to be a promising radioprotector for therapeutic or preventive protocols capable of attenuating the deleterious effects of radiation on human normal tissue, especially for cancer patients undergoing radiotherapy.  相似文献   
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