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61.
Hemolytic effects of water-soluble fullerene derivatives   总被引:3,自引:0,他引:3  
A series of water-soluble fullerene C(60) derivatives has been investigated for their cytotoxic and hemolytic properties, with the aim to correlate structure with toxicity. We observed that cationic chains induce significant toxicity while the presence of neutral or anionic moieties did not produce any response in our model. A validation of these experimental observations has been performed by theoretical studies in which hydrophilic and hydrophobic surface areas were correlated quantitatively with hemolytic properties.  相似文献   
62.
Thirteen hypertensive patients with microvascular angina were studied before and after receiving oral L-arginine (4 weeks, 2 g, 3 times daily). L-arginine significantly improved angina class, systolic blood pressure at rest, and quality of life. Maximal forearm blood flow, plasma L-arginine, L-arginine:asymmetric dimethyl arginine ratio, and cyclic guanylate monophosphate increased significantly after treatment. In medically treated hypertensive patients with micro-vascular angina, oral L-arginine may represent a useful therapeutic option.  相似文献   
63.
64.
Children and adolescents with growth hormone (GH) deficiency (GHD) have reduced bone turnover and bone mass in comparison with normal individuals. GH replacement therapy stimulates bone turnover and improves bone mass during childhood and adolescence. At final height, patients with GHD treated with GH have normal mean values of bone mass, but some patients have reduced lumbar BMD (Z score <1) with an increased susceptibility to fractures. Children and adolescents with GHD have approximately a fourfold decreased fracture frequency during treatment in comparison with controls. The changes of bone mass during the transition to adulthood in patients with GHD who discontinued GH treatment after final height are not defined. An increase of lumbar BMD after final height has been reported until 2 years after discontinuation of GH treatment; this could be the result of a spontaneous progression towards peak bone mass or of a persisting effect of GH treatment on bone mass accumulation. GH has an important role in the accrual of bone mass during childhood and adolescence, but the impact of GHD on bone mass during the transiton to adulthood is unknown.  相似文献   
65.
The interplay between pro- and anti-inflammatory mechanisms during inflammatory and immune responses is critical for avoiding excessive tissue damage. Extracellular nucleotides (e.g., adenosine 5'-triphosphate) may represent constitutive signals that can alert the immune system of abnormal cell death. Relatively high doses of nucleotides induce rapid release of proinflammatory mediators and favor pathogen killing. However, recent findings on antigen presenting cells, particularly dendritic cells, revealed a more complex role for these molecules. Chronic exposure to low-dose nucleotides can redirect cellular responses to prototypic activation stimuli, leading to suppressed inflammation and immune deviation.  相似文献   
66.
Fusariosis is a hyalohyphomycosis due to Fusarium species that mainly occurs in immunocompromised hosts. The clinical spectrum of Fusarium infection comprises localized and disseminated forms. A case of localized cutaneous fusariosis caused by Fusarium solani in a renal transplant patient is described, and the skin manifestations of the disease are discussed.  相似文献   
67.
Pediatric sentinel surveillance of vaccine-preventable diseases in Italy   总被引:2,自引:0,他引:2  
BACKGROUND: Planning and evaluating vaccination programs depend on reliable systems of monitoring disease incidence in the community. In Italy vaccine-preventable diseases are subject to statutory notification, but they are often unreported. In January, 2000, a pediatric sentinel network was launched, with the aim of monitoring in a timely and accurate way the geographic and temporal trends of vaccine-preventable diseases. METHODS: The network consists of National Health System primary care pediatricians; participation is voluntary. The diseases under surveillance include measles, mumps, rubella, pertussis and varicella. Case definitions are based on specific clinical criteria, and pediatricians report cases on a monthly basis. Incidence rates are estimated and compared with those obtained by statutory notifications. The proportion of vaccinated cases is also computed. RESULTS: In 2000 an average of 468 pediatricians participated each month of a total of 7276 pediatricians under contract for primary care by the National Health System. The population under surveillance consisted of 371 670 children younger than 15 years (of a national total of 8.347.804 children of the same age). The annual national incidence per 100.000 children was estimated at 5345 for varicella, 1972 for mumps, 279 for pertussis, 108 for rubella and 62 for measles, although wide variations were observed among geographic areas. The national estimates are 3 to 7 times higher than those obtained through statutory notifications. For all of the diseases the ratio between the two sources of data was significantly higher in southern Italy, compared with the rest of the country. The proportion of vaccinated cases was similar for measles and rubella (21 and 17%) but was approximately 3 times higher for mumps (59%). Most (74%) of the vaccinated mumps cases had received the Rubini vaccine strain. CONCLUSIONS: The sentinel surveillance system is considerably more sensitive than statutory notifications, particularly in southern Italy. The high percentage of mumps cases vaccinated with the Rubini strain indicates a reduced effectiveness of this vaccine. Although further improvements are needed, pediatrician-based sentinel surveillance is a useful tool for evaluating vaccine-preventable disease trends.  相似文献   
68.
OBJECTIVES: In a randomized controlled trial extending over 6 months, we evaluated the effectiveness of acupuncture versus flunarizine in the prophylactic treatment of migraine without aura. METHODS: One hundred sixty women with migraines were randomly assigned to acupuncture treatment (group A, n = 80) or to an oral therapy with flunarizine (group F, n = 80). In group A, acupuncture was carried out in weekly sessions for the first 2 months and then once a month for the next 4 months. The same acupoints were used at each treatment: LR3 Taichong, SP6 Sanyinjiao, ST36 Zusanli, CV12 Zhongwan, LI4 Hegu, PC6 Neiguan, GB20 Fengchi, GB14 Yangbai, EX-HN5 Taiyang, GV20 Baihui. In group F, 10 mg flunarizine were given daily for the first 2 months and then for 20 days per month for the next 4 months. RESULTS: The frequency of attacks and use of symptomatic drugs significantly decreased during treatment in both groups. The number of attacks after 2 and 4 months of therapy was significantly lower in group A than in group F, and analgesic consumption was significantly lower in group A at 2 months of treatment. At 6 months no such differences existed between the two treatment groups. Pain intensity was significantly reduced only by acupuncture treatment. Side effects were significantly less frequent in group A. CONCLUSIONS: Acupuncture proved to be adequate for migraine prophylaxis. Relative to flunarizine, acupuncture treatment exhibited greater effectiveness in the first months of therapy and superior tolerability.  相似文献   
69.
BACKGROUND: The aim of this study was to describe population and primary care morbidity and to examine how the differences vary across the diseases and are influenced by patients' demographic characteristics. METHODS: A comparison of the prevalence of four chronic conditions for 432747 patients from the Health Search Database (HSD) and 119799 individuals from a Health Interview Survey was carried out. A linear regression was performed to study the associations between age and difference in morbidity. RESULTS: Similar prevalence was found for diabetes and hypertension, whereas for chronic obstructive pulmonary disease (COPD) and gastroduodenal ulcer lower HSD prevalence was reported. Among females, age was always associated with morbidity difference. Among males, significant associations were found only for COPD (R2 = 0.81; p = 0.001) and gastroduodenal ulcer (R2 = 0.93; p < 0.001). CONCLUSIONS: The difference between population and primary care morbidity is affected by disease under investigation and patients' demographic characteristics. Therefore, in choosing the more cost-effective approach to collect data such evidence should be taken into account, and results should be interpreted with great caution.  相似文献   
70.
New growth hormone secretagogue (GHS) analogues were synthesized and evaluated for growth hormone releasing activity. This series derived from EP-51389 is based on a gem-diamino structure. Compounds that exhibited higher in vivo GH-releasing potency than hexarelin in rat (subcutaneous administration) were then tested per os in beagle dogs and for their binding affinity to human pituitary GHS receptors and to hGHS-R 1a. Compound 7 (JMV 1843, H-Aib-(d)-Trp-(d)-gTrp-formyl) showed high potency in these tests and was selected for clinical studies.(1)  相似文献   
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