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21.
Resistance to antibacterial agents has increased among many species of bacterial pathogens in the last two decades. While this has been recognized and has been a matter of concern among those concerned with infectious diseases, it is only relatively recently that prescribing physicians have become aware of the problem. A range of official bodies, both national and international, have proposed a range of strategies for controlling this increase in resistance. The relationship between resistance and clinical efficacy or failure is unclear in many areas, although increasingly resistance can be seen to be associated with a less than optimal clinical response. Although the relationship between antibiotic use and resistance is complex, there is an assumption that excessive use of antibacterials may drive an increase in resistance. The term 'prudent prescribing' is frequently used in official documents, but it is not easy for the prescriber to determine exactly what is prudent prescribing. There have been efforts to reduce the unnecessary use of antibacterials in the treatment of many community respiratory infections where the etiological agent is likely to be viral. Guidelines for prescribing have been drawn up by governments and professional societies but their impact can be variable. They need to take account of the changing patterns of resistance, for example the rise in high-level penicillin resistance among pneumococci. They also need to be readily accessible to the practicing clinician. Surveillance systems are available in abundance and these may be local, national, or international. They often, however, suffer from drawbacks and are frequently selective. Frequently the prescriber does not have ready access to the most appropriate data. Integrated strategies to control resistance are urgently needed, as are improved rapid diagnostic facilities.  相似文献   
22.
Marrow radioiron kinetics   总被引:2,自引:0,他引:2  
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23.
Cicatricial conjunctivitis may be a sequel to systemic disorders (eg, Stevens-Johnson syndrome, cicatricial pemphigoid) or local disorders such as chemical burns. The cicatrisation is often associated with corneal epithelial changes that cause visual loss. These have been attributed to encroachment of the conjunctival epithelium over the cornea. However, the epithelial anomalies are poorly understood. We investigated the corneal epithelial changes in cicatricial conjunctivitis with an immunohistochemical study of intermediate filaments in normal and pathological specimens. Our results show that the normal corneal epithelium is immunoreactive for cytokeratin 3 (CK 3) but not cytokeratin 19 (CK 19), whereas normal conjunctival epithelium is CK 3 negative and CK 19 positive. Conjunctiva artificially transposed over the cornea (after therapeutic conjunctival flap reconstruction) retained the normal pattern of conjunctival cytokeratin expression (CK 3 negative, CK 19 positive). Conversely, the entire corneal epithelium exhibited the normal cytokeratin pattern (CK 3 positive, CK 19 negative) in 82% of Stevens-Johnson, 80% of cicatricial pemphigoid, and 69% of chemical burns specimens. The findings suggest that conjunctival encroachment is not responsible for the changes at the corneal surface in cicatricial conjunctivitis and that the abnormal corneal epithelium is derived from native corneal cells in these diseases.  相似文献   
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25.
李承青  彭德民  王彩霞 《医学争鸣》2000,21(12):1439-1439
0 引言 急性乳腺炎是产后妇女的常见病 .我们采用针头挑拨治疗急性乳腺炎 32例 ,疗效显著 .1 临床资料 患者 32例 ,年龄 2 3~ 34 (平均 2 5 .3)岁 ,均为产后哺乳产妇 .其中患乳胀痛为共有症状 .伴发热 10例 ;右侧乳腺炎 14例 ,左侧乳腺炎 16例 ,双侧乳腺炎 2例 ;外上象限胀痛 6例 ,外下象限胀痛 8例 ,内上象限胀痛 7例 ,内下象限胀痛 6例 ,二象限同时胀痛 5例 .乳头均无破损 .患者取卧位 ,显露患乳 ,乳头以碘伏严密消毒后 ,术者持五号针头以指腹常规触诊患乳 ,触摸到肿胀部位后 ,沿乳腺管走行方向找到对应的乳头腺管口 ,以针尖轻轻挑拨…  相似文献   
26.
The aims of the National Diet and Nutrition Survey series are summarized, and the new National Diet and Nutrition Survey of people aged 65 years and over is explored, with particular emphasis on micronutrient intakes and status indices. Mean nutrient intakes were generally satisfactory for most micronutrients, but intakes of vitamin D, Mg, K and Cu were low. Intakes of vitamin D were far below the reference nutrient intake for people aged 65 years and over, and there was also biochemical evidence of vitamin D deficiency, for 8% of free-living and 37% of institution participants, attributed partly to limited exposure to sunlight. A substantial proportion of people living in institutions had inadequate biochemical status indices, notably for vitamin C, Fe and folate. Relationships between intake and status were close for vitamins. Mineral intakes did not correlate well with currently used status indices. Some intakes and indices, especially those of vitamin C, carotenoids, Na and K, were strongly correlated with socio-economic status and with north-south gradients in Britain. Future research challenges should address the functional and health significance of low intakes and sub-optimal biochemical indices for certain micronutrients, especially for people living in institutions; the shortcomings of mineral status indices especially as indicators of mineral intake; the social and geographical inequalities of micronutrient intakes and status, and why micronutrient status deteriorates with increasing age. The answers to these questions will help to define the characteristics of nutritional risk for older people in Britain, and to clarify future needs for education and intervention.  相似文献   
27.
Measures to prevent cricket injuries: an overview   总被引:6,自引:0,他引:6  
Cricket is a major international sport, generally played in British Common-wealth nations. Although strictly a non-contact sport, injuries in cricket can result in a number of ways. In high level cricket, overuse injuries are common and related to the physical demands of the sport, particularly in the delivery of the ball. The bowling action involves repetitive twisting, extension and rotation of the trunk at the same time as absorption of large ground reaction forces over a short period of time. These movements, if performed incorrectly or too frequently, can lead to overuse injuries of the back, particularly in elite and high level cricketers. Cross-sectional studies have demonstrated that spinal overuse injuries occur more frequently to cricketers adopting a mixed bowling action than to those who favour a front- or side-on bowling technique. Strategies to ensure that cricketers do not adopt the mixed action or bowl too fast for extended periods can prevent these back injuries. Injuries resulting from impacts, generally from the cricket ball, can also occur and are more common during low level competition or informal participation. Because of the potential severity of these impacts, a range of protective equipment ranging from body padding to gloves and face protectors are now common features of standard cricket equipment. Although a number of measures to prevent cricket injuries have been widely suggested in the literature, there have been very few studies that have formally assessed their effectiveness in preventing injury. Further research is needed to gain a greater understanding of the biomechanics of cricket actions, the mechanisms of resultant injuries and the role of various risk factors in injury causation.  相似文献   
28.
29.
The male rat striatum was examined for age-related changes in mRNAs expressed in astrocytes and microglia in two rat genotypes that differ by 35% in mean and maximum life spans: F344 and the longer-lived F1 (BN x F344) hybrid. The findings extend the established age-related increases in GFAP (glial fibrillary acidic protein) to other glial mRNAs: two lipoprotein mRNAs that are predominantly expressed in striatal astrocytes, apoE (apolipoprotein E) and apoJ (apolipoprotein J, clusterin, CLI, or SGP-2), and two mRNAs expressed in striatal microglia, TGF-beta1 and complement C1qB. By Northern blot hybridization, both genotypes showed progressive increases of GFAP mRNA to > 2.5-fold by the lifespan. Although the rat strains differed 35% in life span, the slope of the GFAP mRNA regression on age did not differ. Relative to GFAP, the increases of apoE, apoJ, C1q, and TGF-beta1 mRNAs were smaller, < or = 1.5-fold. Because prior studies showed that acute damage to striatal afferents induced astrocyte gene expression increases resembling those that also occur during aging, we examined long-term effects of damage to substantia nigra neurons on striatal astrocyte changes during aging. Young F344 rats were given 6-OHDA lesions that cause striatal dopamine deficits and induce GFAP. When examined 15 months later at age 18 months, there was no effect during prior lesions on the age-related elevation of GFAP mRNA. We conclude that aging changes in striatal GFAP mRNAs do not interact with loss of dopaminergic output to the striatum from 6-OHDA lesions and may be independent of the relatively modest dopaminergic losses during normal aging.  相似文献   
30.
Quality control of leukocyte-reduced packed red cell units (LRprc) produced in blood facilities must conform to regulatory criteria, which state that units may not contain more than 1 x 10(6) to 5 x 10(6) white blood cells (WBC) per unit. The post-filtration WBC content of a total of n = 386 LRprc units was counted with a Nageotte chamber to model the probability that a unit would not meet the regulatory criteria. The distribution of the residual leukocyte counts is close to a negative binomial distribution (NBD) and is independent of the packed red cell volume filtered. The observed probability that a unit of blood has a residual WBC greater than 5 x 10(6) is 2.6 +/- 2.6 x 10(-3). A power analysis of the two-sample Kolmogorov-Smirnov (KS) test in this application shows that a sample size of 20 is sufficient for determining that the process is in control when an out of control process has a k NBD parameter greater than or equal to that of the in control process. The three out of control processes observed to date appear to have this property. A sample of size 80 may be necessary for confirming that process validation data sets conform to the larger 'reference' database (n = 386) for processes that are out of control in such a way that their k NBD parameter is less than the k parameter of the in control process.  相似文献   
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