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[Diagnosis and therapy of Hodgkin's disease in Freiburg in Breisgau 1964 to 1976. 2. Results during the treatment period 1972-1976 compared with the period 1964-1971].

The total group of patients with Hodgkin's disease submitted to primary treatment from May 1964 till December 1976 is divided with respect to diagnostics and therapy into a preponderantly clinically assessed group (CS) treated during the years of 1964 to 1971 (n = 190) and a preponderantly surgically assessed group (PS) treated during the years of 1972 to 1976 (n = 180). The first subgroup was treated with differently large irradiation fields and, in case of combined therapy, mostly with cyclophosphamide. The second subgroup was treated with extended fields, even until total lymphoid irradiation and, in case of drug administration, with primary combined chemotherapy (MOPP). The overall five-year remission rates of both subgroups (stages I to IV) have improved from 35.4% to 54.8% (P less than or equal to 0.001) and the five-year survival rates from 67.2% to 78.2% (P less than or equal to 0.001). If a complete remission was achieved, this was obtained, as far as judgeable, already at an earlier moment in the individual groups: e.g., in stage I with 95.5% after one year as against 94.1% after five years and in stage II with 91.3% after four years as against 72.9% after seven years. The prognostic differences of stages I and II and the histologic manifestations: lymphocytic predominance, nodular sclerosis, and mixed cellularity were equalized under the therapeutic measures of the intensive treatment period.

Adolescent↗

[Structure of the thymus gland of the rat in the prenatal and early postnatal periods of development after exposure to tetracycline during the period of fetogenesis].

Structure of the thymus in Wistar rats has been studied during antenatal and early postnatal periods of ontogenesis by means of histological, morphometric and electron microscopic methods. Theraputic doses of tetracycline hydrochloride have been administered during fetogenesis (15-20 days of pregnancy). An accelerated formation of the thymic structures, cellular blasttransformation in the thymic cortex and movement of lymphocytes from the cortex into medulla and increased secretory activity of epithelioreticulocytes have been revealed. The data obtained are considered as a display of the organ's immune response to tetracycline administration.

Animals↗

[Initiation of auto-oscillation systems of oscillations with the period multiple to the modulation period].

Using a mathematical model of phytoplankton population dynamics as an example, it has been demonstrated that several stable regimes with different regularities branching off from the balance point and from the limiting cycle of a corresponding autonomous system, may appear in the system, while the periodic time dependence of the model parameters is taken into account.

Animals↗

[Metabolism of parenterally administered amino acids in the postoperative period. I. Comparative blood kinetic examinations in healthy adults and in the postoperative period].

The postoperative and posttraumatic period is characterized by alterations of amino acid metabolism which sometimes lead to pronounced blood level imbalances. To investigate the cause of these alterations, we performed pharmacokinetic amino acid utilization studies in 20 patients on the second postoperative day and in 19 healthy adult volunteers. The results indicate that, postoperatively, the majority of amino acids exhibit prolonged half-lives and correspondingly reduced clearances. The necessity for special amino acid solutions for postoperative patients is discussed.

Abdomen↗

Periodic health examination, 1994 update: 3. Primary and secondary prevention of neural tube defects. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To make recommendations on nutritional interventions and screening manoeuvres to prevent the birth of infants with neural tube defects (NTDs). OPTIONS: Folic acid consumption through diet or supplementation in women at low risk and at high risk of having a fetus with an NTD, and maternal serum alpha-fetoprotein (MSAFP) screening in low-risk pregnancies. OUTCOMES: A reduction in the incidence rate of NTDs and potentially harmful effects of false-positive results of screening tests (i.e., abortion of a normal fetus). EVIDENCE: A MEDLINE search with the use of medical subject headings "neural tube defects," "prenatal diagnosis" and "prevention and control" identified 103 original articles published between January 1979 and March 1993. Two reviewers extracted the data by applying the rules of evidence developed by the Canadian Task Force on the Periodic Health Examination. VALUES: The task force's evidence-based methods and values were used; high value was placed on prevention of NTDs and on limitation of the harmful effects of a pregnancy involving a fetus with an NTD. BENEFITS, HARMS AND COSTS: Evidence suggests that folic acid supplementation can decrease the incidence rate of NTDs in low-risk pregnancies by 40% to 60% with no adverse effects. MSAFP screening between the 16th and 18th weeks of gestation can reach a sensitivity of 83% and a specificity of 98% when it is used as part of an organized program. The effect of screening on the incidence rate of NTDs depends on whether affected fetuses are aborted. RECOMMENDATIONS: All women of childbearing age should be advised to increase their consumption of folic acid through diet or supplementation to 0.4 mg/d beginning 1 month before pregnancy and ending at the start of the second trimester. MSAFP screening is recommended in low-risk pregnancies only when it is part of a screening program that includes access to all necessary diagnostic services. High-risk women should be referred to genetic counselling before they plan a pregnancy. VALIDATION: These recommendations are comparable to the current recommendations of the US Centers for Disease Control and Prevention, the Society of Obstetricians and Gynaecologists of Canada, the Canadian Laboratory Centre for Disease Control and the Canadian College of Medical Geneticists, and they were validated through external review. SPONSOR: These guidelines were developed and endorsed by the Canadian task force, which funded by Health Canada.

Canada↗

Periodic health examination, 1995 update: 2. Prevention of dental caries. The Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To make recommendations, based on current evidence, for practising physicians and dentists on interventions for the prevention of dental caries in their patients. OPTIONS: Systemic fluoride administration, professionally administered fluoride, use of fluoride mouth rinses, fissure sealants, oral-hygiene practices, dietary practices, identification of groups at a high risk of dental caries, and early diagnosis and treatment. OUTCOMES: Reduced prevalence of dental caries and fluorosis, longer retention of teeth and lower treatment costs. EVIDENCE: Several MEDLINE searches were conducted for articles published from January 1980 to December 1992, including relevant review articles. VALUES: Relevant clinical findings were evaluated and categorized with the use of the evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination. Recommendations were developed for each method of caries prevention, with reduced incidence of dental caries and improved prevalence of caries-free teeth given high values. BENEFITS, HARMS AND COSTS: The potential benefits of these measures in the long-term are a lower incidence of tooth decay, longer retention of teeth and prevention of fluorosis. The cost saving can be considerable for patients and insurers; however, implementation of some recommendations will be difficult, since the traditional preventive practices of dentists and dental hygienists are not easily changed. RECOMMENDATIONS: There is good evidence that the following manoeuvres are effective in preventing dental caries: use of dentifrices containing fluoride, fluoridation of drinking water, fluoride supplements for patients in areas where there is a low level (0.3 ppm or less) of fluoride in the drinking water, professionally applied topical fluoride and the use of fluoride mouth rinses for patients with very active decay or at a high risk of dental caries and selective use of professionally applied fissure sealants on permanent molar teeth. There is poor evidence that the following manoeuvres are effective in preventing dental caries: professionally applied topical fluoride and the use of fluoride mouth rinses for patients with a low risk of caries, toothbrushing (without a dentifrice containing fluoride) and flossing, cleaning of teeth by a dentist or dental hygienist before topical application of fluoride or at a dental visit and dietary counselling for the general population. There is good evidence to recommend against the use of over-the-counter fluoride mouth rinses by the general population. VALIDATION: These guidelines are compatible with those of the US Preventive Services Task Force. SPONSOR: These guidelines were developed and endorsed by the task force, which is funded by Health Canada. Major funding was provided by the Faculty of Dentistry of the University of Toronto, Toronto and the Faculty of Dentistry of Dalhousie University, Halifax.

Canada↗

Periodic health examination, 1995 update: 1. Screening for human papillomavirus infection in asymptomatic women. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To develop recommendations for practising physicians on the advisability of screening for human papillomavirus (HPV) infection in asymptomatic women. OPTIONS: Visual inspection, Papanicolaou testing, colposcopy or cervicography, use of HPV group-specific antigen, DNA hybridization, dot blot technique, Southern blot technique or polymerase chain reaction followed by physical or chemical therapeutic intervention. OUTCOMES: Evidence for a link between HPV infection and cervical cancer, sensitivity and specificity of HPV screening techniques, effectiveness of treatments for HPV infection, and the social and economic costs incurred by screening. EVIDENCE: MEDLINE was searched for articles published between January 1966 to June 1993 with the use of the key words "papillomavirus," "cervix neoplasms," "mass screening," "prospective studies," "prevalence," "sensitivity," "specificity," "human" and "female." VALUES: Proven cost-effective screening techniques that could lead to decreased morbidity or mortality were given a high value. The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used. BENEFITS, HARMS AND COSTS: Potential benefits are to prevent cervical cancer and eliminate HPV infection. Potential harmful effects include the creation of an unnecessary burden on the health care system and the labelling of otherwise healthy people as patients with a sexually transmitted disease for which therapy is generally ineffective. Potential costs would include expense of testing, increased use of colposcopy and treatment. RECOMMENDATIONS: There is fair evidence to exclude HPV screening (beyond Papanicolaou testing for cervical cancer) in asymptomatic women (grade D recommendation). VALIDATION: The report was reviewed by members of the task force and three external reviewers who were selected to represent different areas of expertise. SPONSORS: These guidelines were developed and endorsed by the task force, which is funded by Health Canada and the National Health Research and Development Program. The principal author (K.J.) was supported in part by the National Health Research and Development Program through a National Health Fellowship (AIDS).

DNA, Viral↗

Periodic health examination, 1994 update: 2. Screening strategies for colorectal cancer. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To make recommendations on the effectiveness of screening for colorectal cancer in asymptomatic patients over 40 years of age. OPTIONS: Multiphase screening that begins with test for fecal occult blood, uniphase screening with sigmoidoscopy and uniphase screening with colonoscopy. Options included screening repeated at different intervals and different procedures for patients with selected risk factors. OUTCOMES: Rates of death, death from cancer and cancer detection; compliance, feasibility and accuracy of each manoeuvre. EVIDENCE: A MEDLINE search for articles published between January 1966 and June 1993 with the use of MeSH terms "screening" and "colorectal neoplasia," a check with the reference sections of review articles published before June 1993 and a survey of content experts. Articles were weighted according to the Canadian Task Force on the Periodic Health Examination levels of evidence. VALUES: The highest value was assigned to manoeuvres that lowered the rate of death from cancer and had a low rate of false-positive results and acceptable cost and compliance. Recommendations were determined by consensus of the authors, members of the task force and colorectal cancer experts. BENEFITS, HARMS AND COSTS: There is evidence that annual fecal occult blood testing with the use of the rehydrated Hemoccult test has a small but significant benefit in lowering the rate of death from cancer after more than 10 years of screening; however, the high rate of false-positive results (9.8%) and the poor sensitivity of annual (49%) and biennial (38%) screening make this a poor method for detecting colorectal cancer. There is fair evidence that screening with sigmoidoscopy may improve survival rates; however, this may be due to volunteer bias. The high cost of and poor compliance with colonoscopic screening make this an unfeasible strategy.

Adult↗

Periodic health examination, 1994 update: 1. Obesity in childhood. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To update the 1979 Canadian Task Force on the Periodic Health Examination recommendation on screening for childhood obesity by reviewing any new evidence concerning health risks in childhood and adulthood, and effective preventive or therapeutic interventions. OPTIONS: Detection: routine measurement of height and weight, use of skinfold thickness measurements, calculation of body mass index (BMI). INTERVENTION: diet, exercise, behaviour modification and comprehensive family-based weight-reduction programs. Components of these interventions could be offered routinely or reserved for children and families who perceive obesity to be a present or potential problem. OUTCOMES: The task force reviewed the probability of obese children become obese adults as a risk factor for adult heart disease and overall related illness and death in adult life as well as obesity as a risk factor for physical and psychologic illness in childhood. EVIDENCE: A MEDLINE search for relevant articles published between January 1981 and February 1991 was undertaken. VALUES: The task force's evidence-based rules for recommendations were used. BENEFITS, HARMS AND COSTS: If weight reduction in childhood were shown to prevent physical or psychologic illness in childhood, or illness and death in adult life, screening and treatment should be recommended. Screening for obesity may cause anxiety on the part of the child and family; malnutrition in children as a result of parents becoming overly anxious about the health risks of obesity has been reported. Most weight reduction programs have limited long-term effectiveness and can be costly. RECOMMENDATIONS: There is insufficient evidence of short-term or long-term benefits from screening for or treatment of childhood obesity to recommend such screening or recommend against it. There is fair evidence to recommend against very-low-kilojoule diets for preadolescents. There is insufficient evidence to recommend for or against exercise programs or intensive family-based programs for most obese children. VALIDATION: These recommendations are similar to those of the American Academy of Pediatrics and the US Preventive Services Task Force. SPONSOR: These guidelines were developed and endorsed by the Canadian task force, which is funded by Health Canada.

Adolescent↗

Periodic health examination, 1993 update: 3. Periodontal diseases: classification, diagnosis, risk factors and prevention. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To review the 1979 Canadian Task Force on the Periodic Health Examination recommendations on the diagnosis and prevention of periodontal disease. OPTIONS: Self-care at home, professional care, treatment with antimicrobial agents and management of patients at high risk. OUTCOMES: Maintaining the gingiva, alveolar bone and periodontal ligament in a healthy state (absence of gingival bleeding and no loss of epithelial attachment). EVIDENCE: A literature search for articles published from 1980 to 1993 was conducted. Selected studies published before 1980 were also reviewed if there were no recent updates. Evidence was evaluated and classified as good, fair or poor according to the criteria of the task force. VALUES: The task force's evidence-based rules for recommendations were used. In addition, whenever feasible, and on the basis of advice from the reviewers and experts, recommendations were modified in the interest of maintaining oral health (e.g., dental flossing in children). BENEFITS, HARMS AND COSTS: The recommendations are not expected to increase the costs of preventing periodontal diseases for the general population. They could benefit dental patients and reduce costs because they are based on the periodontal needs of patients rather than on the current universal application approach.

Adult↗

[Hyperglycemia and the glucose tolerance test in the acute period of myocardial infarct and in the remote post-infarct period].

The blood sugar content was determined in 142 patients with myocardial infarction on the 1--3rd, 7-10th, 28--30th days of the disease by the Hagedorn-Jensen method. The standard glucose tolerance test was conducted in 64 patients on the 30th day of the disease and repeated in 20 patients 18 months after infarction. It was concluded that transient hyperglycemia developed in 47.8% of patients with myocardial infarction in the acute period, predominantly in those with a sugar curve of the diabetes-decipiens type. Carbohydrate tolerance was reduced in two thirds of the patients. In some of them this disorder was attended with clinical signs of diabetes and a severe course of myocardial infarction. In patients with diminished carbohydrate tolerance the sugar curve remained abnormal 18 months after the disease. Obvious diabetes developed in 6 out of 20 patients examined. Among relatives of patients with disturbed carbohydrate metabolism diabetes mellitus was encountered more frequently and the incidence of ischemic heart disease and hypertension was higher.

Acute Disease↗

Enhancement of the periodic acid--Schiff (PAS) and periodic acid--thiocarbohydrazide--silver proteinate (PA-TCH-SP) reaction in LR white sections.

LR White is a well-suited resin for the demonstration of carbohydrates with the PAS or PA-TCH-SP reaction in semithin and ultrathin sections. The intensity of these reactions can be greatly enhanced by using 3 steps in tissue preparation, either singly or in combination: 1) The PAS reaction in semithin sections turns out stronger after partial (70% ethanol) than complete (100% ethanol) dehydration of the tissue before its transfer to 100% LR White. 2) Silver enhancement of the PA-TCH-SP reaction product can simply be effected by physical development of ultrathin sections (PA-TCH-SP-SE reaction). Least precipitates are formed in this procedure, when sections are mounted on uncoated gold grids, processed for cytochemistry, and thinly coated with carbon in the end. 3) The use of hot silver proteinate (50 degrees C) plus strong silver enhancement (15-20 min silver lactate developer) reveals minute concentrations of TCH-labelled aldehyde groups in the tissue that do not react with silver proteinate at room temperature.--Silver enhancement and the use of hot silver proteinate do not depend on LR White, but may also be applied to ultrathin sections of tissue embedded in other resins.

Acrylic Resins↗