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991.
In a study of 19 schizophrenic patients, 7 nonschizophrenic patients, and 31 controls, the authors found significantly higher mean serum levels of 1) immunoglobulin A in schizophrenic women then in control women and in schizophrenic blacks than in either schizophrenic whites or black controls. 2) immunoglobulin D in schizophrenic blacks than in schizophrenic whites, 3) immunoglobulin M in controls than in nonschizophrenic patients, and 4) immunoglobulin G (IgG) in schizophrenics whose urine was positive for phenothiazines than in schizophrenics whose urine was negative for phenothiazines. High serum levels of IgG were associated with no or mild hallucinations and low levels with moderate or severe hallucinations. Black female patients had significantly more severe hallucinaions than white female patients. The authors discuss the possible implications of these findings.  相似文献   
992.
Large crystals of BiVO4 were grown. Extensive twinning can be related to the ferroelastic transition at 528K. The structure of BiVO4 was refined at 4.5, 295 and 566K from powder neutron diffraction data and at 295K from powder X-ray diffraction data by the Rietveld profile technique. Space groups of I41a above and I2b below 528K were confirmed. It is suggested that the transition in BiVO4 is driven by the lone-pair cation Bi3+. The Bi-O polyhedron is regular above the transition but becomes significantly distorted below the transition. This lone-pair distortion increases on cooling from 295 to 4.5K. The V-O tetrahedron remains regular at all temperatures.  相似文献   
993.
The great number of people with varicosities and the relatively high percentage of venous pathology among this group shows the importance of their detection and treatment. The results achieved in more than 1000 operations on varicose legs underline the great benefits arising from surgical treatment of the varicose saphenous vein. The treatment of chronic venous insufficiency in the malleolar region has been aided by the use of the Klapp tenotoma. The simple and atraumatic manipulation of this instrument enables the surgeon to overcome the most important obstacles in this region, the perforator veins (Cockett I, II), the venous leg ulcer and the corona phlebectatica paraplantaris. Conscientious postoperative supervision of the patient by the surgeon personally or by a dermatologist trained in this speciality is an essential condition for the successful operative treatment of varicose veins.  相似文献   
994.
The complement (C) system can solubilize immune precipitates prepared with antibodies of the IgG class, and apparently also of the IgM class. This paper shows that C can also solubilize immune precipitates prepared with two different antigen-binding IgA myeloma proteins. Immune precipitates were prepared with a) mouse myeloma protein TEPC 15 and PC-KLH, and b) mouse myeloma protein MOPC 315 and DNP-BSA. The precipitates could be solubilized by fresh mouse serum, but not by zymosan- or heat-inactivated serum. The rate of solubilization was not affected by the removal of of Ca++ ions. These results verify that the C-mediated solubilization effect can proceed entirely via the alternative C pathway, and lend increased support to the view that the effect is a general phenomenon, not restricted to a particular antibody class or type of antigen.  相似文献   
995.
The configuration of blastoderm-heart cell aggregates after cell sorting depended largely on the proportion of each cell type initially present in the culture. In heterotypic aggregates, blastoderm cells were always found to partially or completely surround heart cells with both cell types retaining their characteristic morphology. Specialized junctions (e.g. desmosomes) developed only between cells of the same type. These observations suggest that blastoderm cells are unable to recognize and form stable contacts with heart cells.  相似文献   
996.
997.
Formulae for the longitudinal shielding effectiveness of N thin, closely spaced, concentric cylinders of high permeability material have been developed and experimentally tested. For shields which cannot be oriented, or which change their orientation in the ambient field, the shielding effectiveness for longitudinal fields is generally the limiting criterion and no design formulae have previously been published for more than two shields. A simple diagrammatical method of writing the shielding formula is presented. Use of these equations is demonstrated by application to the design of magnetic shields for hydrogen maser atomic clocks. Examples of design tradeoffs such as size, weight, and material thickness are discussed. Experimental data on three sets of shields fabricated by three manufacturers are presented.  相似文献   
998.
999.
Nine hundred three former college freshmen were followed 7 yr after entering college by means of a detailed allergy questionnaire. Original data collected from the students as freshmen, including a history of atopy and allergy skin test results, were evaluated in relation to the frequency of developing new allergies. During the 7-yr follow-up period, new cases of hay fever occurred in 12.6%, nonseasonal allergic rhinitis in 4.8%, and new asthma in 2.5%. The risks of developing asthma and allergic rhinitis are both significantly associated with a prior positive allergy skin test. The risk of developing asthma, not hay fever, is significantly associated with a prior history of atopy. The association of positive allergy skin tests with the development of new cases of allergy remains significant throughout the 7-yr follow-up period. However, individuals who had all negative skin tests developed significantly fewer new cases of clinical allergy during the first 3 yr of follow-up; in the next 4 yr of the 7-yr follow-up, increased numbers of individuals with negative scratch tests developed new cases of allergy. Thus, negative skin tests proved of less prognostic value during the last 4-yr period of this 7-yr study, although significant differences still are apparent between the positive and negative reactor groups.  相似文献   
1000.
A study was conducted to determine whether vaccination with sonicated pili of Moraxella bovis would protect cattle from subsequent infection and disease when experimentally challenged by exposure to homologous cultures of M bovis. Some calves were intramuscularly inoculated 2 times with pili of M bovis suspended in water, and others were subcutaneously inoculated 2 times with pili of M bovis suspended in oil; 21 days were allowed between inculations. Controls were nonvaccinated calves. Fourteen days after the last inculation, all calves were exposed to virulent homologous cultures of M bovis. The results indicated that vaccination with sonicated pili of M bovis may induce protective immunity against homologous strain challenge exposure. Vaccines in oil that were injected subcutaneously protected to a greater extent than did vaccines in water that were injected intramuscularly. The development of inflammatory nodules at the site of inoculation was associated with resistance to infection and disease. Only 1 of the vaccinated calves that resisted disease lacked precipitating antibodies against sonicated pili at the time of the challenge exposure. This calf had antibodies 2 weeks later.  相似文献   
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