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71.
A patient with Niemann-Pick disease is reported together with family studies. Her liver and bone marrow were shown to be infiltrated with sea blue histiocytes. Other organs, spleen and lung, were presumably also involved but histological proof was not obtained. Enzyme assay of leucocytes, lymphocytes, and cultured skin fibroblasts showed the patient to be deficient in sphingomyelinase activity. In fibroblasts, activity was 5% of normal while for the parents activity was about 50% of normal. The expected partial deficiency was not found using leucocytes or lymphocytes from the parents. Heat stability studies on fresh fibroblast extracts from the propositus indicated that residual sphingomyelinase activity was slightly more labile than that of the controls. It seems clear that chronic Niemann-Pick disease without neurological involvement is associated with sea blue histiocytosis.  相似文献   
72.
Vibrio cholerae strain 3083 (biotype El Tor, serotype Ogawa) and Texas Star-SR (SR), a mutant derived from 3083 that produces the B (binding) but not the A (toxic) subunit of choleragen, were compared in their abilities to: (i) associate with the infant mouse upper bowel; (ii) survive and multiple there; and (iii) induce diarrhea. Vibrios labeled with 35SO4 were used to determine association with the upper bowel and ability to multiply. The parental strain associated significantly better than SR, although viable mutant cells were found in the infant mouse intestine 16 to 18 h after challenge. Addition of exogenous toxin enhanced the rate at which labeled SR (but not 3083) was cleared, further suggesting that SR associates less well with the upper bowel. Both SR and 3083 multiplied in the upper bowel but, due perhaps to slight net killing during the first 3 h and its more rapid rate of clearance, SR achieved a population size only 10% that of 3083 by 8 h postchallenge. Strain 3083 elicited diarrhea in infant mice but SR did not, even after 10 successive passages through the infant mouse intestine. Strain SR was slightly temperature sensitive at 37 and 40 degrees C. Its potential use as a live vaccine is discussed.  相似文献   
73.
Mouse thymic virus (TA) is a herpesvirus which produces extensive necrosis of the thymus of newborn mice 7 to 14 days after infection. Infectious virus can be recovered from the thymus for only 10 days after infection, with highest titers occurring between days 5 and 7. In mice 5 days old or less, TA infects thymus cells and produces massive necrosis. TA also infects the salivary glands and persists as a chronic infection. Newborn mice infected with TA have no detectable humoral immune response. Infected adult mice respond, and humoral antibody is detected 7 days after infection. Titers are maintained for months thereafter. Regardless of the age of the mice inoculated with TA, persistent infection was established in the salivary glands, but no evidence for thymus involvement was observed when adults were infected. TA does not cross-react serologically by immunofluorescent, complement fixation, or virus neutralization tests with mouse cytomegalovirus; however, interestingly, the epidemiology of the two herpesviruses are similar. Both mouse cytomegalovirus and TA were isolated from the same animals in populations of laboratory and wild mice. Evidence of infection with mouse cytomegalovirus and TA were most apparent by virus isolations, since humoral antibody responses are rarely observed. All strains of mice tested were susceptible to TA infection. However, in some strains maximum necrosis occurred at 7 days, compared with 10 to 14 days for other strains. The difference in age susceptibility and the target tissue of thymus in newborn mice suggests that TA is a model herpesvirus for studying the effects of viral infections on humoral and cell-mediated immunological functions.  相似文献   
74.
The relationship between conjugate lateral eye movements (CLEMs) and alexithymia was investigated in a group of 60 (23 male and 37 female) right-handed university students. Subjects completed the Toronto Alexithymia Scale (TAS), the Schalling-Sifneos Personality Scale, and the Basic Personality Inventory, which measures 12 basic dimensions of personality and psychopathology, CLEMs were recorded while subjects were asked 20 general knowledge questions that have no tendency to elicit eye movements predominantly in one direction. A series of gender by CLEM preference (left vs. right mover) ANOVAs were conducted with the various measures. There was a significant relationship between right CLEM preference and higher scores on the TAS, but no relationships between CLEMs and any of the other measures. These results suggest that alexithymia is associated with left cerebral lateralization, and support the hypothesis that alexithymic characteristics reflect a variation in brain organization.  相似文献   
75.
Fifty-seven male chronic pain patients admitted to an inpatient multimodal pain treatment program at a Midwestern Veterans Administration hospital completed the MMPI, Profile of Mood States (POMS), Tennessee Self-Concept Scale (TSCS), Rathus Assertiveness Schedule (RAS), activity diaries, and an extensive pain questionnaire. All patients were assessed both before and after treatment, and most also were assessed 2–5 months prior to treatment. No significant changes occurred during the baseline period, but significant improvements were evident at posttreatment on most variables: MMPI, POMS, TSCS, RAS, pain severity, sexual functioning, and activity diaries. MMPI subgroup membership, based on a hierarchical cluster analysis in a larger sample, was not predictive of differential treatment outcome. Possible reasons for comparable treatment gains among these subgroups, which previously have been shown to differ on many psychological and behavioral factors, are discussed.This paper originally was presented at the Fourth World Congress on Pain, Seattle, Washington, September, 1984.  相似文献   
76.
AIMS: It has been postulated that the recent world-wide increase in the incidence of non-Hodgkin's lymphoma (NHL) may have been caused by human infection with simian virus 40 (SV40) (a lymphotropic monkey virus that was introduced to man from contaminated poliovirus vaccines between 1955 and 1963); therefore, we set out to determine the incidence of SV40 DNA positivity in lymphoma samples from patients in Tasmania, Australia. METHODS: One hundred lymph node samples, 50 from patients with lymphomas and 50 from controls, were tested using PCR amplification of three SV40-specific primer pairs followed by dot-blot hybridisation. RESULTS: All of the samples tested contained amplifiable DNA, but none contained amplifiable SV40 sequences with any of the primer sets used. CONCLUSIONS: Our results demonstrate absence of SV40 in the lymphoid tissues of our study population in Tasmania, Australia. SV40 does not explain the increasing incidence of NHL in our population.  相似文献   
77.
Genetics can pose special challenges to the principle of confidentiality within the health professional-patient relationship, since genetic information is by its nature both individual and familial. Most professional guidelines allow confidentiality to be broken in rare circumstances, where it will prevent a 'serious', 'imminent' and 'likely' harm. We argue that the types of harms that may result from genetic medicine are particularly diverse. Using clinical examples, we explore ethical issues that arise when balancing individual and family member interests. As genetic testing becomes more, widespread situations will arise where clinicians are faced with a choice between preserving the confidentiality of one patient and preventing harm to another. Professionals need to incorporate the notion of familial implications in their counseling of individuals. Since such dilemmas have been relatively rare in the pre-genetic age, we call for a wider debate on the balance between confidentiality and harm to others.  相似文献   
78.
The present study showed that incorporation of CpG adjuvant into plasmid DNA coding for NcGRA7 antigen resulted in a twofold increase in the level of protection against congenital transfer of Neospora caninum. The level of protection was considerably higher than that observed in pups born from dams immunized with nonrecombinant plasmid.  相似文献   
79.
Denture soft lining materials are compliant cushions used at the oral tissue-denture interface. They are generally required to have sufficient compliance to redistribute mastication load, as well as an adequate modulus for long-term dimensional stability and control over the water uptake. This study investigated the effect of using silane treated fumed silica as a filler on the properties of experimental soft lining materials based on blends of isoprene-styrene (SIS) block co-polymer and mixtures of methyl methacrylate (MMA) and 1,6-hexandiol dimethacrylate (HDMA). The overall elastomer/monomer ratios were maintained, whereas the monomers ranged from 10 to 60% HDMA. The silica filler level was maintained at 10 wt% with respect to SIS. The properties investigated were the dynamic mechanical parameters of storage modulus (E') and tan delta as a function of temperature and the quasi-static mechanical parameters of ultimate tensile strength (UTS) and elongation to break (Eb) as well as absorption properties that were carried out in water and saline. In both unfilled and filled systems there was an increase in E' and a decrease in tan delta with an increase in HDMA. Silica addition tended to increase E' and substantially reduce tan delta in materials with less than 20% HDMA. UTS decreased with filler and HDMA content, however, Eb was greater for filled systems. Generally, in the long term, the water uptake decreased with increasing HDMA content and E'. The silanated silica further reduced the water uptake, indicating a cross-linking effect, thus increasing the restraining force on droplet growth. The uptake in saline was significantly reduced indicating an osmotically controlled uptake process.  相似文献   
80.
We report a patient with bilateral microphthalmia with cyst, limb anomalies, and multiple facial malformations. This patient has clinical features similar to Waardenburg ophthalmo-acromelic syndrome, cerebro-oculo-nasal syndrome, and craniotelencephalic dysplasia. Although all of these syndromes are characterized by microphthalmia, the presently reported patient does not have the complete pattern of any of these syndromes, It is possible that he has a previously undescribed syndrome, most closely related to the cerebro-oculo-nasal syndrome with malformations outside the craniofacial region. More case reports are needed to further delineate this possibly new syndrome.  相似文献   
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