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1.
A new method for vaginal cuff closure at abdominal hysterectomy avoids blood loss and spillage of vaginal contents into the peritoneal cavity. Using two separate running and interlocking absorbable monofilament sutures, the technique keeps the vagina closed at all times and avoids damage to the bladder or ureters. In 77 consecutive patients undergoing abdominal hysterectomy for endometrial cancer, morbidity related to the cuff closure included cuff cellulitis in only 2.6%, granulation tissue in 3.1%, and postoperative bleeding in none of the patients.  相似文献   

2.
OBJECTIVE: The authors investigated the extent and characteristics of published psychiatric research from U.S. and Canadian medical schools that was carried out without external funding. METHOD: They reviewed reports of unfunded research in 14 psychiatric journals, tabulating methodological factors and topics of study. They surveyed first authors about their academic duties and resources used in the studies. RESULTS: Unfunded studies represented 26% of research reports, were usually prospective, most commonly dealt with phenomenology/epidemiology or psychopharmacology, used low levels of technology, and were accomplished on a modest budget of time and money. CONCLUSIONS: Unfunded studies make a substantial and economically efficient contribution to psychiatric research. Future investigations should detail the institutional conditions necessary to sustain this type of research productivity.  相似文献   

3.
The estimated prevalence of obesity in North American children and youth (6 to 17 years) in the 1960s through the 1980s is reported. Use of the triceps skinfold and BMI independently and in combination as indicators of obesity provides different estimates of prevalence due to ethnicity. With the triceps skinfold as the indicator, there is an increase in the prevalence of obesity and a reduction in variation between Black and White children and youth from the 1960s to 1980; however, with the BMI as the indicator, there is no change in the prevalence of obesity and negligible ethnic difference in these national data sets. On the other hand, the prevalence of obesity has increased over time in Mexican American and American Indian children and youth. Data for American children and youth of Asiatic ancestry are limited.  相似文献   

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Abstract

A thermomechanical processing technique is used to improve austenitic Hadfield Mn-steel wear properties. ASTM A128 grade C steel billets were sized and multi-pass hot rolled. Rolling has been successfully carried out up to an 80% reduction in thickness on four passes in the temperature range 1200 to 800 °C. The inter-pass time ranged between 9 to 13 seconds. The steel was then solution treated at 900, 1000 and 1100°C for 30 min. at temperature. Austenite grain size was measured and the carbide volume fraction was evaluated. The austenitic grains of the as-cast structure are surrounded by a network of carbides. The carbides have a lamellar structure and are richer in Cr and Mn than the austenitic grains. Austenitizing at 1100 °C was the optimum to dissolve the network of carbides. However, solution treatment at the higher temperature coarsens the austenite grains while decreasing the carbide volume fraction. By contrast, hot rolling creates finer grains and signficantly reduces the carbide content. Furthermore, hot rolling followed by solution treatment further decreases the carbide content and distributes them homogeneously. This process has a positive effect on both the mechanical and wear properties. High reductions by hot rolling of the Hadfield steel creates both deformation bands and a twinned structure. These twinning boundaries are considered as slip obstacles to provide strengthening. A thick sheet martensitic structure is created accompanying twinning. Moreover, solution treatment of the hot deformed steel leads to the formation of a thin martensitic structure.

On utilise une technique de traitement thermomécanique pour améliorer les propriétés d'usure de l'acier austénitique au manganèse. On a coupé et laminé à chaud par passes multiples des billettes d'acier ASTM A 128, de grade C. On a effectué le laminage, avec succès, jusqu'à une réduction de 80% de l'épaisseur, avec quatre passes dans la gamme de température de 1200 à 800 °C. La durée entre les passes était de 9 à 13 secondes. On a ensuite effectué un traitement de mise en solution à 900, 1000 et 1100°C, pendant 30 minutes à la température donnée. On a mesuré la taille de grain de l'austénite et l'on a évalué la fraction volumique du carbure. Les grains d'austénite de la structure brute de coulée sont entourés d'un réseau de carbures. Les carbures ont une structure lamellaire et sont plus riches en Cr et en Mn que les grains d'austénite. La température optimale d'austénitisation pour la dissolution du réseau de carbures était de 1100 °C. Cependant, le traitement de mise en solution à cette température plus élevée produit un grossissement des grains d'austénite tout en diminuant la fraction volumique de carbure. En contraste, le laminage à chaud crée des grains plus fins et réduit significativement le contenu en carbure. En outre, le laminage à chaud suivi par le traitement de mise en solution diminue encore plus le contenu de carbures et distribue ceux-ci de façon homogène. Ce traitement a un effet positif tant sur les propriétés mécaniques que sur les propriétés d'usure. Des réductions élevées par laminage à chaud de l'acier austénitique au manganèse créent des bandes de déformations ainsi qu'une structure maclée. Ces joints de grains de macle sont considérés comme des obstacles au glissement, fournissant ainsi un renforcement. Une feuille épaisse à structure martensitique, accompagnant le maclage, est ainsi créée. De plus, le traitement de mise en solution de l'acier chaud déformé mène à la formation d'une structure martensitique mince.  相似文献   

6.
S. C. Pepper's (1942) concept of "root metaphor" is used to compare the schools of American social psychology that emerged by the 1930s. The 3 world hypotheses of organicism, mechanism, and contextualism were each influential in shaping schools of thought during the early period of American social psychology. Organicism, which is based on the root metaphor of the organism, formed the conceptual foundation for W. McDougall's (1920) biologically oriented version of social psychology. The mechanistic model, based on the root metaphor of the machine, was reflected in F. H. Allport's (1924) social psychology. Contextualism, with its root metaphor of the historic event, constituted the core of approaches to the field, which assumed that the basic unit of analysis was social interaction rather than the individual. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Populations of marine, estuarine, and freshwater fish from highly urban and industrialized sites in North America often exhibit elevated prevalences of neoplastic, preneoplastic, and nonneoplastic hepatic lesions, and sometimes epidermal neoplasms compared to conspecifics from more pristine reference locales. Positive statistical associations with environmental concentrations of PAHs and other xenobiotics and experimental laboratory studies suggest a chemical etiology to these epizootics. Studies have investigated the expression of carcinogenically relevant genes, the extent of overall DNA damage, somatic cell mutations, germ line polymorphisms, and overall levels of genetic diversity in fish from these populations and other polluted sites. In general, elevated levels of cytochrome P4501A expression have been found in fish from contaminated locales; however, inhibition of gene induction has been seen in hepatic lesions and in normal tissue in fish from the most contaminated sites, perhaps due to genetic adaptation or physiological acclimation. Levels of bulky hepatic DNA adducts, as detected by 32P-postlabeling, are almost always elevated in fish from populations that are exposed to highly contaminated environments. However, levels of DNA adducts were not always predictive of the vulnerability to neoplasia of populations and species from polluted sites. Elevated levels of oxygen radical-induced DNA damage have been observed in hepatic tumors, preneoplastic lesions, and normal livers in a single species of flatfish from contaminated sites; however, the prevalences of these alterations in other species and at other polluted sites has yet to be evaluated. Frequent alterations in the K-ras oncogene have been reported in hepatic neoplasms in several species from highly contaminated sites and also in embryos that were experimentally exposed to oil-contaminated sediments. Studies also suggest that heritable germ line polymorphisms, altered allelic frequencies, and reductions in overall genetic diversity may have occurred in some highly impacted populations; however, the origin and functional significance of altered allelic frequencies have largely yet to be evaluated. In summary, feral fish appear particularly sensitive to DNA alterations from xenobiotics, perhaps due to their unusually high levels of exposure, relatively inefficient DNA repair, and the high frequency of polyploidy in some taxa and provide excellent models to explore the relationships between xenobiotic exposure and altered gene structure and expression.  相似文献   

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A 1-month-old infant presented with a typical pattern of pyloric stenosis but US revealed an intense hyperechogenicity of the thickened pyloric muscle. Cholecystitis and pancreatitis were also present in this child. Familial hyperchylomicronemia was detected. Surgery confirmed the fatty infiltration of the pyloric muscular layer, which was necrotic and inflammatory. Medical management with restriction of fat in the diet led to a complete recovery. This is an exceptional case of pyloric stenosis where the particular echographic appearance of the pyloric muscle led to successful to medical treatment.  相似文献   

11.
A model chromosome number of 120 was obtained for the ancient fish. Polyodon spathula (Pisces: Chondrostei). The karyotype consists of 48 macrochromosomes and 72 microchromosomes. The microchromosomes are like those found in certain other primitive fishes as well as in reptiles and birds. The possiblity that Polyodon is a species of tetraploid origin is strongly suggested by the fact that the 120 chromosomes are easily arranged into 30 groups of four homologs each. Evolutionary comparisons are made with other primitive fish groups.  相似文献   

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In Italy departments of emergency medicine and emergency medical service systems (EMS) were first set up at the end of the 1970s. Since that time many dramatic and significant changes have taken place in the care of the critically ill patient. In Italy the interest in emergency problems and the need for emergency intervention have increased considerably. Nevertheless several problems still have to be solved in order to obtain a standardized organization of the emergency system in Italy and uniform training of emergency care providers.  相似文献   

14.
The incidence of systemic lupus erythematosus in North American Indians   总被引:1,自引:0,他引:1  
The annual incidence (AI) of systemic lupus erythematosus (SLE) was determined in 75 highly inbred North American Indian tribes, a total of approximately 800,000 people, during the fiscal years 1971-1975. Seventy-two of the Indian tribes had an AI of SLE which was of similar magnitude to previously published studies from Sweden, Rochester (Minn.), Alabama, New York City, and San Francisco. However, Three tribes, the Crow, Arapahoe, and Sioux Indians, had a markedly elevated AI of SLE. These three tribes share common historical, geographic, and cultural characteristics. Further, they all reside in the northern half of the United States, in states that do not receive intense sun exposure, thereby eliminating photosensitivity as a major determinant of this increased prevalence. Finally, the AI of SLE in the Sioux Indians was highest for "full-blooded" members and lowest for genetic admixtures.  相似文献   

15.
BACKGROUND: The caffeine-halothane contracture test (CHCT) is the only recognized laboratory test to diagnose malignant hyperthermia (MH). The authors report the results of their analysis of pooled data from the North American Malignant Hyperthermia Registry database to determine the sensitivity and specificity of the CHCT. METHODS: The MH Clinical Grading Scale was used to identify 32 case subjects who were "almost certain" to be MH susceptible based on clinical criteria alone. Their CHCT results were compared with those of a group of 120 control subjects considered to be at low risk for MH. Diagnostic thresholds of the CHCT were adjusted, and its component tests were combined to generate receiver operating characteristic curves. The maximal Youden index for each component test was chosen as the diagnostic threshold indicative of MH susceptibility. RESULTS: The highest sensitivity (97%; 95% CI, 84-100%) was achieved with a two-component test with thresholds of > or = 0.5 g contracture for 3% halothane, > or = 0.3 g contracture at 2 mM caffeine, or both, considered positive for MH. The test specificity was 78% (95% CI, 69-85%). The addition of other CHCT component tests did not improve CHCT sensitivity or specificity. CONCLUSION: The CHCT achieves high sensitivity and acceptable specificity as a clinical laboratory diagnostic test when it is performed according to published standards. However, it cannot be used as a screening test because of the low prevalence of MH in the general population.  相似文献   

16.
We present data showing the degree to which a "biological-psychotherapeutic" division persists in American psychiatry, and how psychiatrists' treatment orientation is associated with personal and professional characteristics. Almost two thirds of academic psychiatrists who responded to our survey (N = 435) could be classified as either biological (27%) or psychotherapeutic (37%) in orientation, according to the proportion of their caseload to which they provided psychotherapy (< or = 25% vs. > 75%). There appears to have been an increase over the last 35 years in the proportion of psychiatrists who can be classified as biologically oriented and a decrease in the proportion who can be classified as psychotherapeutically oriented, as well as the emergence of a large class of intermediate or "eclectic" practitioners (36%). Several personal and professional attributes were distributed differentially according to treatment orientation. Psychotherapeutically oriented respondents more frequently reported personal histories of psychiatric disorders than did biologically oriented respondents (64% vs. 39%) as well as greater satisfaction with clinical work (81% vs. 53% "very satisfied"). Differences were also found in age, gender, history of personal psychotherapy, family history of psychiatric disorder, history of marijuana use, degrees of involvement in research, teaching and clinical care of patients, and overall work satisfaction, as well as other characteristics.  相似文献   

17.
A cross-cultural perspective on paranoia is developed, based on a synthesis of three distinct areas of research, with particular attention to the Black experience in America. This perspective is applied in a two-phase program of research. Phase I was the secondary analysis of data from an epidemiologic study of schizophrenia and depression: It examined differences in paranoid symptom expression among Black, Latino, and White Americans. Phase II, called the Culturally-Sensitive Diagnostic Interview Research Project, is currently underway and involves primary data collection, focusing exclusively on African Americans. Phase I results and some pilot data from the phase II study are reported. It is concluded that cultural mistrust among Black psychiatric patients should not be construed as psychopathology.  相似文献   

18.
In serial reversal learning, subjects learn to respond differentially to 2 stimuli. When the task is fully acquired, reward contingencies are reversed, requiring the subject to relearn the altered associations. This alternation of acquisition and reversal can be repeated many times, and the ability of a species to adapt to this regimen has been considered as an indication of behavioral flexibility. Serial reversal learning of 2-choice discriminations was contrasted in 3 related species of North American corvids: pinyon jays (Gymnorhinus cyanocephalus), which are highly social; Clark's nutcrackers (Nucifraga columbiana), which are relatively solitary but specialized for spatial memory; and western scrub jays (Aphelocoma californica), which are ecological generalists. Pinyon jays displayed significantly lower error rates than did nutcrackers or scrub jays after reversal of reward contingencies for both spatial and color stimuli. The effect was most apparent in the 1st session following each reversal and did not reflect species differences in the rate of initial discrimination learning. All 3 species improved their performance over successive reversals and showed significant transfer between color and spatial tasks, suggesting a generalized learning strategy. The results are consistent with an evolutionary association between behavioral flexibility and social complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
OBJECTIVE: To clarify the contribution of the Asp905Tyr polymorphism of the muscle-specific glycogen-targeting subunit of protein phosphatase 1 (PP1G) to insulin resistance and related diseases. RESEARCH DESIGN AND METHODS: We investigated the Asp905Tyr polymorphism of the PPP1R3 gene, which encodes the muscle-specific glycogen-targeting subunit of PP1G, in 259 Japanese patients with NIDDM and 194 healthy control subjects. RESULTS: No significant difference was found in the genotype distribution between NIDDM patients (N = 259; Asp/Asp = 0.10, Asp/Tyr = 0.44, Tyr/Try = 0.46) and healthy control subjects (n = 194; Asp/Asp = 0.13, Asp/Tyr = 0.37, Tyr/Tyr = 0.50) or between patient groups subdivided by the mode of treatment: NIDDM patients with insulin therapy (Asp/Asp = 0.14, Asp/Tyr = 0.46, Tyr/Tyr = 0.40) and those without insulin therapy (Asp/Asp = 0.07, Asp/Tyr = 0.43, Tyr/Tyr = 0.50). However, NIDDM patients with the Tyr allele, which was previously reported to be associated with insulin resistance, tended to have lower BMIs than those without this allele (Asp/Asp: 24.5 +/- 1.1 kg/m2, Asp/Tyr: 22.6 +/- 0.4 kg/m2, Tyr/Tyr: 22.8 + 0.3 kg/m2, P = 0.06 by analysis of variance). CONCLUSIONS: These data suggest that the Asp905Tyr polymorphism of the PPP1R3 gene is not associated with NIDDM or high BMI, both of which are known to be insulin-resistant states, in the Japanese population.  相似文献   

20.
Thirteen hundred and fifty dogs were examined under anesthesia at veterinary hospitals in the USA and Canada. Periodontal health was recorded in detail. Teeth were frequently absent (particularly lower third molar, upper and lower first premolars, and incisor teeth). Calculus was most extensive on the upper fourth premolar and molar teeth. Missing teeth, mobility of remaining teeth, extent of calculus and gingival inflammation, and furcation exposure and attachment loss all were more common in small dogs compared with larger dogs, and in order dogs compared with younger dogs.  相似文献   

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