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81.
We present the case of a 69-years-old man who was admitted to hospital with multiple myeloma. IgG-kappa type monoclonal protein was detected in the serum. When we separated the serum obtained from blood sample of the patient and the lid of the collecting tube was opened, the patient's serum became gelled immediately. When the lid of the collecting tube remained closed, the patient's serum did not become gelled even at 4 degrees C. Moreover, the gelled serum of the patient did not resolve at 56 degrees C. Taken together, these results indicated that gel formation of the patient's serum may not be due to cryoglobulin. It was found that the pH of the patient's serum elevated to pH 8.0 quickly after exposed to air. It was also found that the patient's serum, but not the sera of other IgG-kappa multiple myeloma patients, became gelled as soon as PBS of pH 8.0 was added. These results highly suggest that the patient's serum becomes gelled at pH 8.0. However, the isoelectric focusing of isolated precipitation in the patient showed fractions around the pH 8.5-8.7 zone, which was different from the pH at which the precipitation began to form. We think that this may be the first report of a multiple myeloma patient whose serum becomes gelled after exposed to air.  相似文献   
82.
Summary We report on a sporadic case satisfied with a proposed diagnostic criteria for Cohen syndrome. This 10 year-old Japanese boy had truncal obesity, short stature, mild mental retardation, hypotonia, maxillary hypoplasia, micrognathia, narrow hands and feet, high-arched palate, prominent upper central incisors, high nasal bridge, but no pigmentary retinopathy. Autosomal recessive manner of inheritance was suggested by the pedigree.  相似文献   
83.
A case of multiple myeloma (IgA-Λ) with marked granulocytosis, which measured up to 9.9×104/mm3, Is described. Matured neutrophiles were predominant and blasts were not found in the peripheral blood. The serum granulocyte colony-stimulating factor (G-CSF) was notably elevated. The disease ran a chronic course and granulocytosis and elevated serum G-CSF continued. The patient developed atelectasis and bronchopneumonia, and died of respiratory failure. At autopsy, bone marrow showed marked myeloid hyperplasia in varying states of differentiation. The enlarged spleen also disclosed numerous myeloid cells of varying differentiation. Small aggregations of atypical plasma cells were present in the marrow and spleen. Immunohisto-chemically, atyplcal plasma cells were positive for anti-G-CSF antibody, which Indicated G-CSF secretion from the myeloma cells. To our knowledge, this is the first reported case of G-CSF-producing multiple myeloma.  相似文献   
84.
Two cases of disseminated infection caused by Mycobacterium intracellulare were reported and discussed. In the first case, the patient was a fifty-seven-year-old male who complained of general fatigue, weight loss, and fever. Biopsy of the right inguinal lymph nodes and the liver revealed infiltration by histiocytes engulfing many acid-fast bacilli. At autopsy an egg-sized abscess was found is the region of the right Iliac lymph nodes. Histological examination showed histiocytic infiltration in the abscess wall, neighboring lymph nodes, liver, and spleen. In the second case, the patient was a four-year-old boy, who had persistent fever and splenomegaly. Splenectomy was performed and histological examination of the spleen revealed multiple nodular infiltration by swollen histiocytes with many acid-fast bacilli in their cytoplasm. The bone marrow aspirates and liver tissue obtained in the necropsy also showed many histiocytes containing many acid-fast bacilli. The authors emphasized the importance of paying special attention to atypical mycobacteriosis in feverish patients having lesions with a proliferation of histiocytes.  相似文献   
85.
We used functional magnetic resonance imaging (fMRI) and dual tasks to investigate the physiology of how movements become automatic. Normal subjects were asked to practice some self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Our secondary task was a letter-counting task where subjects were asked to identify the number of times a target letter from the letter sequences was seen. Only the performances that achieved high accuracy in both single and dual tasks were considered automatic. The fMRI results before and after automaticity was achieved were compared. Our data showed that for both conditions, sequential movements activated similar brain regions. No additional activity was observed in the automatic condition. There was less activity in bilateral cerebellum, presupplementary motor area, cingulate cortex, left caudate nucleus, premotor cortex, parietal cortex, and prefrontal cortex during the automatic stage. These findings suggest that most of the motor network participates in executing automatic movements and that it becomes more efficient as movements become more automatic. Our results do not provide evidence for any area to become more activated for automatic movements.  相似文献   
86.
The dynamic characteristics of the baroreflex neural arc from pressure input to efferent sympathetic nerve activity (SNA) reveal derivative characteristics in the frequency range of 0.01 to 0.8 Hz (i.e., the baroreflex gain augments with increasing frequency) and high-cut characteristics in the frequency range above 0.8 Hz (i.e., the baroreflex gain decreases with increasing frequency) in rabbits. The derivative characteristics accelerate the arterial pressure regulation via the baroreflex. The high-cut characteristics preserve the baroreflex gain against pulsatile pressure by attenuating the high-frequency components less necessary for arterial pressure regulation. However, to what extent the carotid sinus baroreceptor transduction from pressure input to afferent baroreceptor nerve activity (BNA) contributes to these characteristics remains unanswered. To test the hypothesis that the carotid sinus pressure-BNA transduction partly explains the derivative characteristics but not the highcut characteristics, we examined the dynamic BNA response to pressure input in the frequency range from 0.01 to 3 Hz by using a white noise analysis in 7 anesthetized rabbits. The transfer function from pressure input to BNA showed slight derivative characteristics in the frequency range from 0.01 to 0.3 Hz with approximately a 1.7-fold increase in dynamic gain, but it showed no high-cut characteristics. In conclusion, the carotid sinus baroreceptor transduction partly explained the derivative characteristics but not the high-cut characteristics of the baroreflex neural arc. The present results suggest the importance of the central processing from BNA to efferent SNA to account for the overall dynamic characteristics of the baroreflex neural arc.  相似文献   
87.
The M-CSF and its receptor (M-CSFR, CSF-1R or c-fms proto-oncogene) system were initially implicated as essential in mammals for normal monocyte development as well as for pregnancy. To allow a comparison with the M-CSF and M-CSFR system of an oviparous animal, we cloned a M-CSFR-like gene from rainbow trout (Oncorhynchus mykiss). The gene was cloned from a cDNA library of head kidney. It contained an open reading frame encoding 967 amino acids with a predicted size of 109 kDa. The putative amino acid sequence of rainbow trout M-CSFR showed 54% amino acid identity to fugu (Takifugu rubripes) M-CSFR, 52% to zebrafish (Danio rerio) M-CSFR and 40% to mouse (Mus musculus) and human (Homo sapiens) M-CSFR. The M-CSFR-like gene was constitutively expressed in head kidney, kidney, intestine, spleen and blood. The gene was detected especially in the ovary of immature female rainbow trout. These results suggest that a M-CSFR-like receptor may be involved in female reproductive tracts even in an oviparous animal like fish.  相似文献   
88.
89.
In the prespermatogenesis period, male germ cells (gonocytes) begin to reproliferate and move to the basement membrane of the seminiferous tubule. Although these two events-reproliferation and relocation-are important for establishment of spermatogenesis, they have not been greatly analyzed both in a mechanical and in an endocrine or paracrine aspect. In this study, the relationship between reproliferation and relocation of gonocytes was examined, using the thymidine analog bromodeoxyuridine (BrdU) labeling method and transmission electron microscopy (TEM). BrdU was injected into the fetuses [day 13.5 post coitus (dpc) to 18.5 dpc] and pups [day 0. 5 post partum (dpp) to 6.5 dpp] of C57BL/6J mice. Two hours later, BrdU positive gonocytes were examined immunohistochemically and these data were analyzed. TEM and LM observation was carried out as well. Gonocytes began to relocate on the basement membrane from 18.5 dpc (1.4%) while BrdU-labeled gonocytes were first detected on 1.5 dpp (13.6%). Relocated BrdU-negative gonocytes were recognized from 18.5 dpc (1.4%), and relocated BrdU-labeled gonocytes were recognized from 1.5 dpp (8.4%). On the other hand, non-relocated BrdU-labeled gonocytes were detected from 1.5 dpp (5.2%). Gonocyte relocation began 2 days earlier than reproliferation during the late fetal period. After birth, the two events occurred at random. These results indicate that the reproliferation of the gonocyte does not correlate with relocation. The two events may be regulated by different mechanisms.  相似文献   
90.
A humanized monoclonal IgG1 antibody, designated hC4G1, recognizes the fibrinogen receptor glycoprotein (GP)IIb/IIIa on platelets and inhibits platelet aggregation. When the F(ab′)2 fragment of hC4G1 (F(ab′)2 hC4G1) was administered to cynomolgus monkeys, all the monkeys showed inhibition of platelet aggregation ex vivo. Unexpectedly, a significant decrease in platelet count was observed in 5 of 18 monkeys. Antibodies against F(ab′)2 hC4G1 were detected in the plasma of these monkeys by ELISA. Antibody activity in the plasma of these monkeys was significantly correlated with the intensity of platelet decrease (r = 0.84). The natural monkey antibodies to F(ab′)2 hC4G1 were directed against the C-terminal region of F(ab′)2 fragment common to all human and humanized IgG antibodies. Natural homo-reactive antibodies were also detected in human plasma from 15 of 40 healthy volunteers. Specificity was closely similar to that of the monkey antibodies. Affinity-purified human homo-reactive antibodies enhanced phagocytosis of platelets treated with the F(ab′)2 hC4G1. Monkey plasma with high homo-reactive antibody activity was confirmed to decrease platelet count when administered together with F(ab′)2 hC4G1 to a monkey with low antibody activity. These results suggest that F(ab′)2 of humanized and human antibodies causes elimination of the corresponding antigens from the circulation by homo-reactive antibodies.  相似文献   
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