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991.
During the 1960s and 1970s tuberculosis was severely neglected in developing countries. Less than 50% of patients diagnosed were cured. However, an international breakthrough occurred in the 1980s with the excellent results from a short-course treatment: 80% cured. This was first achieved in Tanzania. Since 1993, this innovative approach has been known throughout the world as the 'directly observed treatment, short-course' (DOTS) strategy. Over the past 15 years the interest in international tuberculosis control has substantially improved. There has been a strong increase in the number of initiatives to rapidly extend the use of DOTS so that internationally set targets for tuberculosis control can be met (by 2005, 70% of infectious patients detected and 85% of these cured). The highest priority has been given to the 22 countries with the highest incidence of tuberculosis. There has been a significant increase in the number of countries implementing DOTS. The average rate of cure using DOTS is 80%. Since the 1970s the Royal Netherlands Tuberculosis Association (Koninklijke Nederlandse Centrale Vereniging tot Bestrijding der Tuberculose (KNCV)) has been involved in many international initiatives, such as the Stop TB Partnership, and it has participated in the development and implementation of policies for tuberculosis and tuberculosis-HIV control. However, there are still causes for concern: the number of tuberculosis patients is increasing in particular due to the tuberculosis-HIV co-epidemic and it is estimated that only 1 in 4 infectious tuberculosis patients were detected and treated in DOTS programmes during the year 2000. 相似文献
992.
Y Kotani PS McNulty K Abumi BW Cunningham K Kaneda PC McAfee 《Canadian Metallurgical Quarterly》1998,23(14):1559-1565
STUDY DESIGN: The biomechanical role of the cervical uncovertebral joint was investigated using human cadaveric spines. Sequential resection of cervical uncovertebral joints, including clinical anteromedial foraminotomy, was conducted, followed by biomechanical testing after each stage of resection. OBJECTIVES: To clarify the biomechanical role of uncovertebral joints and clinical anteromedial foraminotomy in the cervical spine and their effects on interbody bone graft stability. SUMMARY OF BACKGROUND DATA: Although the biomechanical role of the cervical uncovertebral joints has been considered to be that of a guiding mechanism in flexion and extension and a limiting mechanism in posterior translation and lateral bending, there have been no studies quantifying this role. According to results in quantitative anatomic studies, anatomic variations exist in uncovertebral joints, depending on the vertebral level, articular angulation, and relative height of the joints. METHODS: Fourteen human functional spinal units at C3-C4 and C6-C7 underwent sequential uncovertebral joint resection, with each stage of resection followed by biomechanical testing. The uncovertebral joint was divided anatomically into three parts on each side: the posterior foraminal part, the posterior half, and the anterior half. The loading modes included torsion, flexion, extension, and lateral bending. A simulated anterior bone graft construct was also tested after each uncovertebral joint resection procedure. RESULTS: Significant changes in stability were observed after sequential uncovertebral joint resection in all loading modes (P < 0.05). The biomechanical contribution of uncovertebral joints decreased in the following order: the posterior foraminal part, the posterior half, and the anterior half. Unilateral and bilateral foraminotomy most affected the stability of the functional spinal unit during extension, causing a 30% and 36% decrease in stiffness of the functional spinal unit, respectively. The effect was less in torsion and lateral bending. After sequential resection, there was a statistically significant difference between decreases in torsional stiffness at C3-C4 and C6-C7 (P < 0.05). The stiffness of the simulated bone graft construct decreased progressively during flexion and lateral bending after each foraminotomy (P < 0.05). Increased bone graft height of 79% returned stability to the preforaminotomy level. CONCLUSIONS: This is the first study to quantitate the biomechanical role of uncovertebral joints in cervical segmental stability and the effect at each intervertebral level. The effect differs because of anatomic variations in uncovertebral joints. The major biomechanical function of uncovertebral joints includes the regulation of extension and lateral bending motion, followed by torsion, which is mainly provided by the posterior uncovertebral joints. This study highlights the clinical assessment of additional segmental instability attributed to destruction of the uncovertebral joints during surgical procedures or by neoplastic lesions. 相似文献
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994.
AA Kruize OP van Bijsterveld RJ Hené PC de Wilde TE Feltkamp L Kater JW Bijlsma 《Canadian Metallurgical Quarterly》1997,81(6):435-438
The reliability and validity of a Confidence of Dental Hygienist in Child Management Scale were examined. Forty-eight dental hygiene students, nine dental staff, and thirty-one dentists were subjects for the reliability and validity scale. The acceptable level of the reliability on the Scale was shown by internal consistency and stability. The confidence scores of the clinician's group were significantly higher than the confidence scores of the students. The reliability and validity of the Confidence Scale were established. Next, we evaluated the effect of behavioral science training, using videotape feedback and role playing on twelve dental hygiene students. Six students received the training, the other six students, the controls, had no training. The confidence scores of the training group were significantly higher than those of the control group, demonstrating that the training was effective for dental hygiene students. 相似文献
995.
996.
ED Williamson SM Eley KF Griffin M Green P Russell SE Leary PC Oyston T Easterbrook KM Reddin A Robinson 《Canadian Metallurgical Quarterly》1995,12(3-4):223-230
In this study, we have determined the limit of protection achievable by immunisation with sub-units of Yersinia pestis against the development of plague in an experimental animal model. Co-immunisation with the purified culture-derived F1 and the recombinant V sub-units afforded a greater level of protection than with either sub-unit alone. The protection given by the combined sub-units was several orders of magnitude greater than that afforded by the whole cell killed (Cutter USP) vaccine and was equivalent to that achieved by vaccination with EV76, the live attenuated Y. pestis vaccine strain. However, the combined sub-unit vaccine has clear advantages over the live vaccine in terms of safety of use and absence of side-effects. 相似文献
997.
LB Johnson PC Kuo EJ Schweitzer LE Ratner DK Klassen EW Hoehn-Saric A dela Torre MR Weir J Strange ST Bartlett 《Canadian Metallurgical Quarterly》1996,62(11):1581-1583
BACKGROUND: In 1994, a policy of double renal allografting (DUAL) was used at two centers within our local organ procurement organization to increase utilization of kidneys from older donors that would otherwise be discarded. Both kidneys from an older donor (age > 60 years) were selectively transplanted into a single adult recipient. METHODS: The relative impact of a DUAL policy on the utilization of older donor kidneys is examined for the period of April 1994 to April 1996. Actual utilization is compared with the hypothetical case in which a DUAL policy is not present. RESULTS: In the actual setting, a total of 75 kidneys from older donors (> 60 years) were accepted for transplantation. Thirty-six kidneys were transplanted as singlets, and 16 additional kidneys were transplanted as DUAL renal allografts. Thus, a 44% increase in transplantable kidneys, and a 22% increase in patients transplanted with kidneys from older donors, was realized. In the actual setting, 23 older kidneys were discarded; without the DUAL policy, 39 kidneys would have been deemed untransplantable. When compared with the actual (n = 52) and hypothetical number of kidneys transplanted without a policy of DUAL transplantation (n = 36), the DUAL policy significantly increased the utilization of older donor kidneys (P = 0.01). The actuarial 1-year graft survival rate of the dual kidneys was 100%, with a mean follow-up of 11.1 +/- 2.9 months. Mean 6-month and 1-year serum creatinine level were 1.76 +/- 0.4 and 1.63 +/- 0.6 mg/dl, respectively. CONCLUSIONS: A DUAL policy significantly increased the number of older donor kidneys transplanted in a single organ procurement organization and reduced the rate of discard of older donor kidneys over a 2-year period. Long-term follow-up is necessary to substantiate satisfactory graft function in DUAL from older donors. 相似文献
998.
999.
1000.
OBJECTIVE: To establish the efficacy and acceptability of combined continuous low-dose oestrogen and low-dose progestogen therapy, to determine whether any of three commercially available progestogens had any advantages or disadvantages in these circumstances and whether use of the lowest clinically effective oestrogen dose affected other outcomes being measured. DESIGN: A 12-month, prospective, open label, single centre, randomised trial. PATIENTS AND METHODS: Seventy-five postmenopausal women already receiving hormone replacement therapy in the form of conjugated equine oestrogens (CEE) (0.625 mg daily) and cyclical medroxyprogesterone acetate (10 mg) and experiencing withdrawal bleeding were changed to a continuous daily regimen of 0.3 mg CEE and a random allocation of one of three low-dose progestogens (medroxyprogesterone acetate 2.5 mg, levonorgestrel 30 micrograms or norethisterone 350 micrograms). Return to a dose of 0.625 mg CEE was permitted if required to control menopausal symptoms with separate analysis of this group when appropriate. OUTCOMES MEASURED: Menopausal symptom score, clinical bleeding pattern, endometrial biopsy results, forearm bone density and content, serum lipids and side effects. RESULTS: Fifteen women withdrew from the trial, five because of irregular bleeding. In the remainder, amenorrhoea was achieved in 53% by three months, in 67% by six months and in 93% by 12 months. Endometrial biopsy showed atrophic endometrium by 12 months in all but one patient, in whom minimal proliferative activity was seen. Twenty-seven women chose to return to a dose of 0.625 mg CEE. In all groups, final control of menopausal symptoms improved. All regimens were bone sparing and the lipid profile was unchanged. Minimal side effects were experienced by the patients. There was little difference in outcome between the three progestogens except that norethisterone therapy was associated with a greater prevalence of amenorrhoea at six months than was seen in the levonorgestrel and medroxyprogesterone acetate groups. CONCLUSIONS: These low-dose continuous oestrogen and progestogen regimens appear an appropriate option for the postmenopausal woman wishing to eliminate withdrawal bleeding and reduce both hormonal side effects and menopausal symptoms. The long term benefits of these regimens with regard to the prevention of osteoporotic fractures, cardiovascular disease and endometrial cancer need to be further assessed over time. 相似文献