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91.
Subarachnoid hemorrhage has a much higher intensity in magnetic resonance (MR) images with the passage of time. Acute subarachnoid hemorrhage is difficult to see; within 1 week its appearance has become intensified on T1-weighted images. Different concentrations of blood and lysed red blood cells in cerebrospinal fluid (CSF) were examined spectroscopically but did not significantly alter T1 and T2 relaxation of CSF acutely. Ultraviolet visible spectroscopy of bloody CSF stored hypoxically for 3 days showed the presence of methemoglobin. The iron in methemoglobin is paramagnetic; in combination with water this facilitates T1 relaxation. It is concluded that methemoglobin formation with T1 shortening at least partially accounts for the increasing intensity of the MR appearance of subarachnoid hemorrhage over time in the central nervous system and may also explain the intense appearance of subacute hemorrhage in MR images elsewhere in the body. 相似文献
92.
93.
The head nurse occupies an important position in the nursing unit Concerning leadership style, a distinction is traditionally made between consideration and initiating structure Sometimes a third style is distinguished as well, namely 'production-orientated' leadership In a study of 561 nurses from 16 general hospitals in The Netherlands, the influence of two leadership styles upon the reactions of nurses (job satisfaction, experienced meaningfulness, health complaints and absenteeism) to their work situations was examined, namely the styles of social (i e consideration) and instrumental leadership (a combination of the styles initiating structure and production-onentated) The separate effects of the two styles were studied, as well as the connection between combinations of leadership styles and reactions The results indicate that social leadership contributes positively to nurses' reactions to their job Instrumental leadership, on the other hand, leads to health complaints From the analyses of combinations of leadership styles it appears that nurses are most satisfied if the head nurse pays much attention to both dimensions of leadership For health complaints, a tendency in this directions is also found Finally, it becomes clear that nurses with a great need for autonomy prefer a different type of leadership from nurses with little need for autonomy 相似文献
94.
95.
Platelet adhesion to collagen types I through VIII under conditions of stasis and flow is mediated by GPIa/IIa (alpha 2 beta 1-integrin) 总被引:13,自引:6,他引:7
Saelman EU; Nieuwenhuis HK; Hese KM; de Groot PG; Heijnen HF; Sage EH; Williams S; McKeown L; Gralnick HR; Sixma JJ 《Blood》1994,83(5):1244-1250
Platelet adhesion to fibrillar collagens (types I, II, III, and V) and nonfibrillar collagens (types IV, VI, VII, and VIII) was investigated in the presence of physiologic concentrations of divalent cations under conditions of stasis and flow. Under static conditions, platelet adhesion was observed to collagen types I through VII but not to type VIII. Under flow conditions, platelet adhesion to collagen types I, II, III, and IV was almost independent of shear rates above 300/s. Collagen type V was nonadhesive. Platelet adhesion to collagen type VI was shear rate-dependent and optimal at a rate of 300/s. Collagen types VII and VIII showed minor reactivity and supported platelet adhesion only between shear rates 100 to 1,000/s. Monoclonal antibody (MoAb) 176D7, directed against platelet membrane glycoprotein Ia (GPIa; very late antigen [VLA]-alpha 2 subunit), completely inhibited platelet adhesion to all collagens tested, under conditions of both stasis and flow. Platelet adhesion to collagen type III at shear rate 1,600/s was only inhibited for 85%. The concentration of antibody required for complete inhibition of platelet adhesion was dependent on the shear rate and the reactivity of the collagen. An MoAb directed against GPIIa (VLA-beta subunit) partially inhibited platelet adhesion to collagen. These results show that GPIa-IIa is a major and universal platelet receptor for eight unique types of collagen. 相似文献
96.
Ultrasonically guided punctures. A modified technique 总被引:2,自引:0,他引:2
97.
Jan Gentle RMN RGN RCNT RNT BSc PG Dip 《Journal of advanced nursing》1996,24(6):1194-1200
This paper describes a qualitative research study which explored the practices and views of nurses working on a new Mental Health Intensive Care Unit A review of the literature identified the main aspects of intensive care provision (1) physical security, (2) characteristics of the patient group, (3) staff-patient ratios, (4) therapeutic environment and (5) multi-agency involvement Twenty-one periods of participant observation helped form the questions for a semi structured in-depth tape recorded interview in which 11 out of a total of 16 trained nurses took part The information is categorized and the discussion is informed by observation of practice The nurses perceived the following as the main issues that the physical environment is inadequate for security, that the patient group appears to have the common characteristic of being unwanted in other clinical settings, that the staff-patient ratio is inadequate and that their vision of the nature of a therapeutic environment is vague 相似文献
98.
Perceived food intolerance in subjects with irritable bowel syndrome-- etiology, prevalence and consequences 总被引:2,自引:0,他引:2
OBJECTIVES: This study estimates the prevalence of perceived food intolerance and its consequences in subjects with irritable bowel syndrome (IBS), evaluates the utility of common tests for food intolerance, studies the relation between perceived food intolerance and other disorders, and discusses the etiology. DESIGN: Cross-sectional study. SETTING: National health survey. SUBJECTS: A selection of the population (n=11,078) in Oppland county, Norway, was invited to a health screening, and a sample of subjects with IBS were included in the study. INTERVENTIONS: A medical history of food intolerance, musculoskeletal pain, mood disorders and abdominal complaints was taken, and tests were performed for food allergy and malabsorption. A dietician evaluated the dietary habits of the subjects. RESULTS: Out of 4,622 subjects with adequately filled-in questionnaires, 84 were included in the study, 59 (70%) had symptoms related to intake of food, 62% limited or excluded food items from the diet and 12% had an inadequate diet. The mean numbers of food items related to symptoms and the number of foods limited or excluded from the diet were 4.8 and 2.5, respectively. There were no associations between the tests for food allergy and malabsorption and perceived food intolerance. Perceived food intolerance was unrelated to musculoskeletal pain and mood disorders. CONCLUSIONS: Perceived food intolerance is a common problem with significant nutritional consequences in a population with IBS. The uselessness of current antibody tests and tests for malabsorption and the lack of correlation to psychiatric co-morbidity make the etiology obscure. 相似文献
99.
中药升麻的化学成分 总被引:14,自引:0,他引:14
从中药兴安升麻[Cimicifuga dahurica(Turcz.)Maxim.]的干燥根茎中分得五个化合物,其中四个为三萜木糖甙:升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅰ),25-O-乙酰升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅱ),12-羟基升麻醇-3-O-β-D-吡喃木糖甙(23R,24S)(Ⅲ),升麻醇-3-O-β-D-吡喃木糖基(3→1)-β-D-吡喃木糖甙(23R,24S)(Ⅳ),另一个为异阿魏酸(Ⅴ)。Ⅲ和Ⅳ为新化合物,通过光谱(IR,MS,1H及13C NMR)解析确定了它们的结构,分别命名为升麻甙A(cimiside A)和升麻甙B(cimiside B)。 相似文献
100.
DS Howale A Mishra AK Asthana D Sharma PG Gaikwad 《Journal of the Anatomical Society of India》2012,61(2):258-261
Biologists and physical anthropologists attempted to classify human being into races according to phenotypic variations. The latter are based either on one or two phenotypic characters therefore the outcome is unable to givq clear distinction among different races. Cranial index seems to be an important,tool, which may be used to identify the races in different geographical regions. 75 dried skulls collected from different part of Maharashtra were measured to determine the cranial index. Skulls were classified by the method of Montagu (1960)2 Average maximum cranial length and breadth were found to be 17.11 cm and 12.98 cm respectively and maximum & minimum cranial lengths were observed to be 18.50 and 16.60 cm and cranial breadths were noted to be 14.50 and 12.10 cm respectively. Average cranial index (mean ± SD) was 75.49 ± 3.95. In our study most of the skulls were grouped under the Mesocranial (46.66%) and Dolichocranial (42.66%) categorises when based on Montagu and Dolichocranial categorises when 56% based Comas'. As per the conclusion Maharashtrian population belongs to Indo-Dravidian race. 相似文献