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941.
942.
How left–right (LR) asymmetric forms in the animal body is a fundamental problem in Developmental Biology. Although the mechanisms for LR asymmetry are well studied in some species, they are still poorly understood in invertebrates. We previously showed that the intrinsic LR asymmetry of cells (designated as cell chirality) drives LR asymmetric development in the Drosophila embryonic hindgut, although the machinery of the cell chirality formation remains elusive. Here, we found that the Drosophila homologue of the Id gene, extra macrochaetae (emc), is required for the normal LR asymmetric morphogenesis of this organ. Id proteins, including Emc, are known to interact with and inhibit E‐box‐binding proteins (E proteins), such as Drosophila Daughterless (Da). We found that the suppression of da by wild‐type emc was essential for cell chirality formation and for normal LR asymmetric development of the embryonic hindgut. Myosin ID (MyoID), which encodes the Drosophila Myosin ID protein, is known to regulate cell chirality. We further showed that Emc‐Da regulates cell chirality formation, in which Emc functions upstream of or parallel to MyoID. Abnormal Id‐E protein regulation is involved in various human diseases. Our results suggest that defects in cell shape may contribute to the pathogenesis of such diseases.  相似文献   
943.
Journal of Artificial Organs - The purpose of this study was to assess the accuracy and reliability of a continuous blood glucose monitoring system (artificial endocrine pancreas; STG-55, Nikkiso,...  相似文献   
944.
Journal of Artificial Organs - Left ventricular assist device is an established therapeutic option for the patient with end-stage heart failure. Recently, durable continuous-flow devices have...  相似文献   
945.
946.
OBJECTIVE: The aim of the present study was to characterize the excess hard tissue on the mandible of the microphthalmic mouse having a mutation at the mitf locus. DESIGN: Homozygous mutant (mi/mi) and wild-type (+/+) mice were obtained by mating a breeding pair (strain name, B6C3Fe a/a-Mitf(mi)/J). We used mi/mi and +/+ mice at ages 6, 7, 8, 9, 28, and 49 days for micro-computed tomographic and histologic analyses. RESULTS: Excess hard tissue was found on the mesio-buccal surface of the mandibular first molar in all 11mi/mi mice, but none was found in the 8mi/+ or 14 +/+ mice. The excess hard tissue was located in the mental foramen connected to the mandibular canal. The mandibular canal passed near the basal part of the incisor and the root of the mandibular first molar due to aberrant development of the teeth and mandible. The excess hard tissue contained predentine immunostained for dentine sialoprotein, a marker for early stages of dentinogenesis, which was first observed at about 7 days of age. Dentine, predentine, pulp, and root-like structures were observed in the excess hard tissue, but neither enamel nor enamel organ was observed. CONCLUSION: Odontogenic cells in the basal part of the incisor and/or the mandibular first molar with the ability to develop into odontoblasts and pulp cells appeared to migrate through the mandibular canal to the mental foramen, where they developed into odontoblasts and pulp-like cells, and then formed dentine and predentine-like structures.  相似文献   
947.
Many articles address the predictability of immediate implant placement into extraction sockets; however, there are only a few reports that mention the indications and limitations of this technique. The aim of this article is to re-examine specific indications for immediate implant placement and to clarify the timing or "fourth dimension" relative to extraction and implant placement. The expanded concept of four-dimensional implant treatment planning involves the new axis of time, which must be considered along with the traditional spatial or three-dimensional management of implant positioning.  相似文献   
948.
We investigated the changes in cardiac autonomic nervous activities during long-term nonpulsatile left heart bypass (NLHB) by analyzing heart rate variability. A pulsatile ventricular assist device was installed in 3 goats, and pulsatile left heart bypass (PLHB) was conducted for 2 weeks. Then, NLHB was maintained for the following 4 weeks. The segmental data of the R-R intervals (R-Rs) was analyzed by maximum entropy spectral analysis. Changes in evaluated parameters from the last week of PLHB to the 4th week of NLHB were as follows: the mean R-Rs increased from 511 ms to 692 ms; the coefficient of variation of R-R increased from 10.2 to 14.1%; the power of the low frequency band (LF) increased from 747 ms2 to 2,855 ms2; the power of the high frequency band (HF) increased from 512 ms2 to 1,270 ms2; and the ratio of LF to HF increased from 2.6 to 6.5. These results indicated that the cardiac autonomic nervous activity, both sympathetic and parasympathetic, increased during long-term NLHB.  相似文献   
949.
A patient with massive rectal bleeding due to ileal tuberculosis is reported. Technetium-99m labelled red blood cell scintigraphy indicated hemorrhage from the ileum, and laparotomy was then carried out. A 70-cm segment of ileum containing ulcers and erosions was resected, and epitheloid granuloma with Langhans-type giant cell was found in the resected specimen. Massive rectal bleeding is considered a rare presenting symptom of intestinal tuberculosis. Intestinal tuberculosis, including small intestinal tuberculosis, although uncommon, should be taken into consideration as a cause of rectal bleeding. Received: September 16, 1998 / Accepted: February 26, 1999  相似文献   
950.
The aim of this study was to clarify the effect of living alone on the cognitive function of older people and the mediating effect of instrumental activities of daily living (IADL) ability.The data for a final sample of 3276 participants aged 65 years and above who did not require long-term care at the baseline were used from a 4-year prospective cohort study conducted in Kasama City, Japan. Demographic data including age, sex, and depression at baseline were used as covariates. The Kihon checklist evaluated the IADL ability at baseline and cognitive function at follow-up. The characteristics of those living alone and with others were compared using the student t test and χ2 test. The effect of living alone on cognitive function was analyzed using logistic regression analysis. Mediation analyses determined the mediating effects of IADL.A total of 325 participants were living alone; they were significantly older than those living with others, more likely to be female, not provide emotional support, and have low physical function, more severe depression, and lower IADL disability. Living alone had a significantly lower risk of cognitive decline at follow-up than living with others. The mediation analysis revealed that IADL disability at follow-up was significantly associated with cognitive decline. Thus, greater IADL ability decreased cognitive decline risk.Older people living alone had a significantly lower risk of cognitive decline, and cognitive function significantly mediated IADL ability. Health support for enhancing IADL abilities may help older people living alone maintain good cognitive function.  相似文献   
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