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991.
To study the role of central cholinergic mechanisms in hypertension, we have determined muscarinic receptors using [3H](-)quinuclidinyl benzilate (QNB) and choline acetyltransferase (ChAT) activity in the brain regions of spontaneously hypertensive rats (SHR), stroke-prone SHR (SHRSP) and renal hypertensive rats. The number of muscarinic receptors was significantly (33–38%) elevated in the hypothalamus of SHR and SHRSP at the ages of 16 and 24 weeks compared to that of Wistar-Kyoto rats (WKY). An increased density of muscarinic receptors was consistently observed in the prehypertensive (5 weeks) and developmental (10 weeks) stages of hypertension. In contrast, in the hypothalamus of rats with renal hypertension there was no muscarinic receptor alteration. The receptor alteration in the SHRSP hypothalamus was not abolished by a chronic hypotensive treatment which prevented the development of hypertension, suggesting that an enhancement of the muscarinic receptors in spontaneous hypertension does not occur secondarily to the elevation of blood pressure. The hypothalamus of SHR and SHRSP at the ages of 5 and 24 weeks showed significantly less activity of ChAT. These data demonstrate that there is a specific increase in muscarinic receptors and a decrease in cholinergic activity in the hypothalamus of SHR and SHRSP. Thus, the present study suggests an important role for hypothalamic cholinergic receptors in the pathogenesis of spontaneous hypertension.  相似文献   
992.
Iron deficiency without anemia (IDNA), the most prevalent nutritional deficiency worldwide, affects young women of reproductive age. This study aimed to elucidate the relationship between IDNA and mental and somatic symptoms including anger and fatigue using the Japanese version of the Cornell Medical Index Health Questionnaire (CMI–J). Data regarding demographic characteristics, anthropometry, hematological, and biochemical indices of the iron status, frequencies of selected food intakes assessed by self-administered food frequency questionnaires (FFQs), frequencies of nonspecific symptoms, and grades of neurotic tendencies assessed by CMI–J were collected from 76 young women aged 18–22 years living in the metropolitan area of Tokyo, Japan. The subjects were classified as having IDNA (hemoglobin (Hb)?≥?12 g/dL and serum ferritin?<?20 ng/mL; n?=?29), having iron deficiency anemia (IDA) (Hb?<?12 g/dL and serum ferritin?<?20 ng/mL; n?=?10), or having a normal iron status (Hb?≥?12 g/dL and serum ferritin?≥?20 ng/mL; n?=?36). One subject was excluded from the analyses because of Hb?<?12 g/dL and serum ferritin?≥?20 ng/mL. Fisher’s protected least significant difference and the Dwass–Steel–Chritchlow–Fligner multiple comparison tests were used to compare the data of the three groups. P values <0.05 were considered significant. Sections M–R (mental complaints) were significantly higher in the IDNA subjects than in the normal subjects. No significant difference in CMI scores was found between the normal and IDA subjects. Sections I (fatigability), Q (anger), and R (tension) were significantly higher in the IDNA subjects than in the normal subjects, regardless of no significant differences between the normal and IDA subjects in those sections. Young women with IDNA demonstrated a significantly higher proportion of neurotic tendencies (grades II–IV). The intake frequency score of canned or bottled green tea fortified with vitamin C was significantly higher in the IDNA subjects than the IDA subjects. The findings suggest that IDNA may be a risk factor for anger, fatigue, and tension in women of childbearing age.  相似文献   
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In order to reveal the genetic relationship of tetraploids and pentaploids in the agamospermous species Taraxacum albidum Dahlst., an allozyme study was carried out. Approximately 200 plants putatively identified as T. albidum were collected mainly from the Kyushu Island of Japan, and analyzed by enzyme electrophoresis. Two multilocus genotypes at 14 presumptive loci of nine enzymes, Type A and Type B, were detected. Most of the sample plants showed uniclonal Type A, which corresponds to “T. albidum” as reported in our previous paper. Type B, which is also uniclonal, was found at fewer localities and was clearly different from Type A in the allele composition of pgi-2 and pgm-1, as well as in the allele dosage at mdh and sod-1. By means of flow cytometry and chromosome count, the ploidy levels of Type A and Type B were shown to be pentaploid and tetraploid, respectively. A comparison of the allele composition suggests a hybrid origin of pentaploid T. albidum (Type A) from an unreduced gamete of Type B and a reduced gamete of any diploid Taraxacum species.  相似文献   
998.
Guinea pig and mouse C1q, subcomponents of the first component of complement, contained six asparagine-linked sugar chains on the C-terminal non-collagenous globular regions of each molecule. After N-acetylation and successive NaB3H4-reduction of asparagine-linked sugar chains liberated by hydrazinolysis, their structure was analysed by sequential exoglycosidase digestion in combination with sugar composition analyses. The sugar chains of C1q molecules of both animals were very similar and composed of the biantennary complex type sugar chains with the following outer chains in various combinations: (± NeuNAcα → )Galß1 → GlcNAcß1 → and Galß1 → Galß1 → GlcNAcß1 →. These chain moieties were found to be linked to a common core structure of Manα1 → (Manα1 → )Manß1 → GlcNAcß1 → (Fucα1 → )GlcNAc.  相似文献   
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