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71.
Wnt signaling plays an essential role in neuronal specification of the dorsal spinal cord 总被引:14,自引:0,他引:14
In the developing spinal cord, signals from the roof plate are required for the development of three classes of dorsal interneuron: D1, D2, and D3, listed from dorsal to ventral. Here, we demonstrate that absence of Wnt1 and Wnt3a, normally expressed in the roof plate, leads to diminished development of D1 and D2 neurons and a compensatory increase in D3 neuron populations. This occurs without significantly altered expression of BMP and related genes in the roof plate. Moreover, Wnt3a protein induces expression of D1 and D2 markers in the isolated medial region of the chick neural plate, and Noggin does not interfere with this induction. Thus, Wnt signaling plays a critical role in the specification of cell types for dorsal interneurons. 相似文献
72.
Tomomi Yamaguchi Shujiro Hayashi Daisuke Hayashi Takeshi Matsuyama Norimichi Koitabashi Kenichi Ogiwara Masaaki Noda Chiai Nakada Shinya Fujiki Akira Furutachi Yasuhiko Tanabe Michiko Yamanaka Aki Ishikawa Miyako Mizukami Asako Mizuguchi Kazumitsu Sugiura Makoto Sumi Hirokuni Yamazawa Atsushi Izawa Yuko Wada Tomomi Fujikawa Yuri Takiguchi Keiko Wakui Kyoko Takano Shin-Ya Nishio Tomoki Kosho 《American journal of medical genetics. Part A》2023,191(1):37-51
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples. 相似文献
73.
We have developed a breast-conserving surgery consisting of quadrantectomy and regional lymph node dissection and immediate
volume replacement using lateral tissue flap (LTF). The quadrantectomy was employed on the basis of segmental anatomy of the
duct lobular system in which breast carcinoma originates. Lateral skin incision was performed from the apex of mid-axillary
line to the inframammary fold, without removing the skin overlying the tumor. In the early period of breast reconstruction
embraced latissmus dorsi flap (LDF) for 10 patients (reconstruction was not performed on 35 patients), but in the late period
we employed LTF for 56 patients. Four of the 101 patients developed ipsilateral breast cancer during a mean follow-up period
of 48 months, but none died of breast cancer. Among the 56 patients with LTF replacement no patient developed ipsilateral
breast cancer. Fairly good cosmetic outcome was obtained in the patients who underwent the immediate volume replacement. Breast-conserving
surgeries are reviewed, and the surgical procedure using LTF for immediate volume replacement is described. 相似文献
74.
Risk factors for breast cancer: A case-control study of screen-detected breast cancer in Miyagi Prefecture, Japan 总被引:7,自引:0,他引:7
Yuko Minami Noriaki Ohuchi Akira Fukao Shigeru Hisamichi 《Breast cancer research and treatment》1997,44(3):225-233
We examined the associations between reproductive factors and the risk of breast cancer on the basis of information from a total of 201,363 breast cancer screening program participants in Miyagi Prefecture, Japan, during 1987-1991. A case-control study method was applied on analysis. Data on 204 breast cancer cases identified and 810 screening year-, age- and screening area-matched normal controls were extracted. After adjustment for potential confounders, a trend of decreasing risk of breast cancer with increasing number of parity was observed (p for trend=0.03). Among parous women, lactation for the last child decreased the risk of breast cancer (odds ratio (OR) = 0.61, 95% confidence interval (95% CI) 0.39–0.94). These findings were consistent with those in clinical breast cancer reported previously. When cases were divided into two age groups, younger ( 49 y.o.) and older (50 y.o. ), family history of breast cancer among mother and sisters (OR=3.51, 95% CI 1.05–11.80), and lactation for the last child (OR=0.46, 95% CI 0.25–0.84) were associated with younger age breast cancer, whereas number of parity was associated with older age breast cancer (p for trend=0.03). The results by age group suggest that different mechanisms may exist in breast cancer developing at early and late onsets. 相似文献
75.
Extraadrenal abnormal uptake on adrenocortical scintigraphy has been reported rarely in the normal gallbladder, lipid cell tumor of the ovary, or in clear cell type renal cell carcinoma. Clear cell type renal cell carcinoma contains glycogen and cholesterol like the adrenal gland, but the uptake of the radionuclide I-131 cholesterol has been reported to be low and not sufficient to image it. Right renal and adrenal masses were incidentally discovered on abdominal CT scan in a patient with chronic renal failure resulting in bilateral acquired cystic kidney disease. Adrenocortical scintigraphy done to know the nature of the adrenal mass showed high uptake corresponding to the right renal mass and the right adrenal mass. Clear cell type renal cell carcinoma and adrenal adenoma with prominent clear cells were histologically confirmed on hematoxylin-eosin stain and in an immunohistochemical study with renal cell antibody. Not only low-density lipoprotein receptors mediated uptake but also overall replacement of the right non-tumorous renal parenchyma by acquired cysts may have played a role in imaging the renal cell carcinoma on adrenocortical scintigraphy. 相似文献
76.
Masayuki Sasaki Yuichi Ichiya Yasuo Kuwabara Yuko Akashi Tsuyoshi Yoshida Toshimitsu Fukumura Sadayuki Murayama Teruyoshi Ishida Kenji Sugio Kouji Masuda 《European journal of nuclear medicine and molecular imaging》1996,23(7):741-747
We evaluated the usefulness of fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) in the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer and then compared the findings with the results of X-ray CT by region based on the histological diagnoses. We examined 29 patients with non-small cell lung cancer. One hundred and thirty-two mediastinal lymph nodes were surgically removed and the histological diagnoses were confirmed. FDG PET images, including 146 mediastinal regions, were visually analysed and the mediastinal lymph nodes were scored as positive when the FDG uptake was higher than that in the other mediastinal structures. On the X-ray CT scans, any mediastinal lymph nodes with a diameter of 10 mm or larger were scored as positive. All three examinations were successfully performed on 71 regions. For FDG PET, we found a sensitivity of 76%, a specificity of 98% and an accuracy of 93%. On the other hand, for X-ray CT a sensitivity of 65%, a specificity of 87% and an accuracy of 82% were observed. A significant difference was observed in respect of both specificity and accuracy (P<0.05). Based on the above findings, FDG PET is suggested to be superior to X-ray CT when used for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer. 相似文献
77.
Summary Two cases of McArdle's syndrome are reported. One is a classical exaple; the other is unusual because of the in vitro presence of muscle phosphorylase activity. In the latter case. the electronmicroscopic investigation confirmed the diagnosis.The fine structural changes characteristic of this disease are summarized and it is concluded that histochemical studies alone are insufficient to exclude the diagnosis of McArdle's myopathy. 相似文献
78.
Hideki Horita M.D. Eiichi Hoashi M.D. Yuko Okuyama M.D. Koumei Kumagai M.D. Shiro Endo M.D. 《Psychiatry and clinical neurosciences》1977,31(3):393-402
We observed the attacks of nystagmus in a case of infantile spasms and carried out overnight sleep polygraphy. The following findings were obtained:
- 1 Awake time was prolonged to 56% of TIB, while sleep time was markedly shortened to 44% of TIB. Also REM sleep time was reduced to 20% of SPT and deep slow sleep (stage N3) was absent.
- 2 Attacks of nystagmus were observed only during wakefulness. At first, fast wave bursts appeared in the right occipital area, and were followed by left-upward deviations of eyeballs, and then the attacks of counterclockwise right-downward rotatory nystagmus. Also the fast wave bursts were succeeded by spreading of fast waves to adjacent areas. At the same time, EMG exhibited elevated muscle action potentials of mentalis and biceps fernoris. During the attacks of nystagmus, there was alteration of respiratory movements.
79.
80.