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91.
BACKGROUND: Pharmacogenetics is the science of the influence of heredity on pharmacological response. ISSUES: The cost of severe adverse drug reactions in individuals has been estimated in the US alone to be in excess of US$4 billion. It has been argued that in a significant proportion of cases, the efficacy and toxicity profiles of drug therapy would be substantially improved in individuals if characteristics due to genetic variation were taken into account. Methods are now available, which make screening for susceptibility feasible. CONCLUSIONS: There are several therapeutic areas in which screening may give rise to significant improvements in outcome with cost-benefits to both the individual and the community. However, there is currently a lack of data on which cost-benefit analysis can be based. The challenge is to provide this information for new drugs, and for drugs with established therapeutic roles.  相似文献   
92.
Substance abuse testing and treatment programs for adolescents using drugs are receiving increased attention on high school campuses. Many policymakers question drug testing and the treatment models for adolescent substance abusers. This paper explores the impact of drug testing. Treatment models and approaches for substance abuse are presented. It is recommended that treatment counselors explore drug testing in relationship to treatment models for substance use. We advise counselors to consider comprehensive programs for adolescents based on their belief systems and values assigned to moral, medical and social models of treatment.  相似文献   
93.
Semi-interpenetrating networks (semi-IPN's) based on linear poly(phenylene ether)s and crosslinked polystyrene can be prepared by reactive moulding of crosslinkable polymeric mixtures. These materials show thermomechanical properties which strongly depend on both the ratio of the two polymeric matrices and the degree of crosslinking in the polystyrene network. Samples based on a 50/50 weight ratio of poly(2,6-dimethyl-1,4-phenylene oxide)/crosslinked polystyrene show glass transition temperatures (Tg) which are very dependent on the degree of crosslinking. It is therefore possible to obtain materials with desired Tg, ranging from the Tg of the corresponding linear blend to that of poly(2,6-dimethyl-1,4-phenylene oxide) alone.  相似文献   
94.
To date microscopy and cultural isolation still remain the “gold standard” in the laboratory diagnostics of mycobacteria. Nucleic acid amplification techniques additionally enable a rapid and sensitive detection of Mycobacterium tuberculosis. However, bacterial growth is still required for species identification and susceptibility testing which should be performed from one of the first isolates of every patient and repeated after about 2 months if cultures are still positive. By means of DNA fingerprint techniques, the confirmation of transmission, of TB outbreaks, and also of laboratory cross-contamination is feasible.  相似文献   
95.
We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up.  相似文献   
96.
The following article presents two new cases of a lipofibroma of the median nerve. This formation is a very rare benign tumor of peripheral nerve tissue. Up to now 30 cases have been reported in the literature and are reviewed in this article and are compared with the two cases reported. Besides the operative treatment, which made the neuropathological diagnosis possible, preoperative diagnosis has been extended by MNT-scans of the involved parts of the nerve. The noninfiltrating character of the tumor could be well recognized on these scans. The signal quality and the anatomical proximity to the median nerve made the diagnosis of a lipofibroma likely. By the postoperative histological reviews the diagnosis was confirmed in classic manner. The immunological marking of the S-100 protein showed a remarkable reduction of this protein in these peripheral nerve tumors. The two cases reported by us recapitulate the clinical history typically and describe symptoms and our treatment for the lipofibroma of the median nerve.  相似文献   
97.
The Changing Faces of the Nutcracker Esophagus   总被引:3,自引:0,他引:3  
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed.  相似文献   
98.
99.
An increasing number of patients desire body contouring surgery after massive weight loss, whether from bariatric surgery or a change in lifestyle. The fact that many body regions lose their elasticity and tissue-tension has led to stepwise treatments including abdominoplasty, thigh lift, buttocks and hip lift or liposuction. However, these procedures often do not treat the reason for the deformities. The lower body lift first described by Ted Lockwood in 1993 is a procedure that allows simultaneous skin resection and tightening of different regions including the abdomen, buttocks, hips, and thighs. In this article the authors present their 10-year experience with the body lift. Patient selection, technical details, pre- and postoperative care, complications, and expected results are all discussed.  相似文献   
100.
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