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91.
Differential expression of the beta I- and beta II-PKC subspecies in the postnatal developing rat brain; an immunocytochemical study. 总被引:1,自引:0,他引:1
Differential expression of protein kinase C subspecies, beta I- and beta II-PKC, derived from a single gene by alternative splicing was evidenced in the postnatal developing rat brain. Immunoblot analysis of the PKC subspecies in the whole developing brain showed that beta I-PKC was present at birth and then gradually increased, while beta II-PKC was not present at birth or on postnatal day 3, then increased rapidly from day 7 to the maximum value seen in the adult brain. Under light microscopy, beta I-PKC immunoreactivities seen at birth were the most intense in the brainstem and intense in the diagonal bundle and globus pallidus. beta I-PKC immunoreactivities in these neurons weakened from day 7 and disappeared in the adult brain, while in the cerebral cortex, triangular septal nucleus and pontine nucleus beta I-PKC immunoreactivities were week at birth and then gradually increased. beta II-PKC immunoreactivities were first visible in neurons on day 7 and increased progressively. beta I- and beta II-PKCs were not co-localized in a neuron, as far as examined. The immunoreactivities of beta I-PKC at birth were localized in growth cone-like structures as well as in the dendrites and perikarya. Similarly, alpha-PKC was also present at birth in the growth cone-like structure. Immunoblot analysis revealed that beta I-PKC was present at birth in the growth cone-rich fraction from the hindbrain but not in that from the forebrain, while alpha-PKC was found in the growth cone-rich fraction from both the forebrain and the hindbrain. beta II- and gamma-PKC were not detected in the growth cone-rich fraction from either forebrain or hindbrain. These findings suggest that beta I- and beta II-PKC play a role in different stages of development and in different neurons; both beta-subspecies may be involved in postnatal developing neuronal functions while only beta I-PKC plays functional roles in the growth cone, in the prenatal developmental stage. 相似文献
92.
Minoru Yagi Takeshi Mishina Tsukasa Fujishima Kazutoshi Date Hiroshi Saito Nobuo Suzuki 《Surgery today》1997,27(1):84-87
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children. 相似文献
93.
Genetic alteration in carcinoid tumors of the lung. 总被引:1,自引:0,他引:1
Kenji Sugio Toshihiro Osaki Tsunehiro Oyama Mitsuhiro Takenoyama Takeshi Hanagiri Masaru Morita Koji Yamazaki Akira Nagashima Hisashi Nakahashi Yoshihiko Maehara Kosei Yasumoto 《Annals of thoracic and cardiovascular surgery》2003,9(3):149-154
Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis. 相似文献
94.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients. 相似文献
95.
Leiomyosarcoma originating in Meckel's diverticulum: Report of a case and a review of 59 cases in the English literature 总被引:1,自引:0,他引:1
Nobuyuki Shimizu Shu Kuramoto Toshiki Mimura Kaoru Kobayashi Masanori Kobayashi Shigeru Sakai Michio Kaminishi Takeshi Oohara 《Surgery today》1997,27(6):546-549
A 49-year-old woman was referred to our hospital with complaints of epigastric colicky pain and high fever. Abdominal computed
tomography and ultrasonography showed a solid tumor in the lower abdomen. Laparotomy revealed a neoplastic mass arising in
Meckel's diverticulum; therefore, a segment of the ileum, including the tumor-possessing diverticulum, was resected with a
lymph node dissection. A histologic examination confirmed the lesion to be leiomyosarcoma. In the English literature, 59 cases
of leiomyosarcoma in Meckel's diverticulum were reported from 1941 to 1994. The majority of patients were in their 4th decade
of life, with both sexes equally affected. The most frequent symptoms associated with this disease were abdominal pain with
nausea, vomiting, and melena. The majority were larger than egg-size. Although Meckel's diverticulum is difficult to diagnose
preoperatively, mesenteric arteriography may at times prove useful. The standard management of this particular tumor is wide
segmental resection, including the tumor and diverticulum with lymph node dissection. 相似文献
96.
To elucidate the molecular basis for endocrine tumorigenesis, p53 mutations in human endocrine tumors were analyzed by using polymerase chain reaction-single strand conformation polymorphism. Exons 5 through 10 of the p53 gene were studied in genomic DNAs from 134 primary endocrine tumors and 6 human endocrine cancer-derived cell lines. Mutations were detected and identified in 4 endocrine tumors, including one parathyroid adenoma and three thyroid carcinoma cell lines. The sites of these mutations were in exons 5 (codon 151 and 152) and 7 (codon 248 and 255). In all of three tumor cell lines, but not in a parathyroid adenoma, the normal allele encoding the p53 gene was lost. However, p53 mutations were not found in any other endocrine tumors or cell lines. Based upon these results, we concluded that the p53 gene may play a role in the tumorigenesis of a limited number of parathyroid adenoma and thyroid cancers, and that the p53 mutation with an allelic loss of the p53 gene is an important factor in malignant tumorigenesis of the thyroid gland. 相似文献
97.
H Sasano Y Saito H Nagura R Kudo M Rojas S G Silverberg 《International journal of gynecological pathology》1991,10(3):252-259
The lectin-binding properties of 44 cases of serous and mucinous ovarian cystadenoma, tumor of low malignant potential (LMP), and invasive carcinoma were examined histochemically. Wheat germ agglutinin (WGA), concanavalin A (con A), Ulex europaeus agglutinin I (UEA-I), peanut agglutinin (PNA), Ricinus communis agglutinin I (RCA-I), soybean agglutinin (SBA), and Robina pseudoaccacia (RPA) were employed. All the lectins examined were bound to neoplastic epithelial cells of benign and malignant tumors, but none bound exclusively to ovarian tumor cells. Different lectin-binding patterns between serous and mucinous neoplasms were observed, with the exception of RPA. UEA-I, con A, RPA, and PNA in serous neoplasms and UEA-I, RPA, and WGA in mucinous neoplasms demonstrated lectin-binding properties of LMP tumors intermediate between those of cystadenoma and invasive carcinoma. These findings indicate that serous and mucinous ovarian neoplasms contain different glycoconjugates, that malignant transformation of the neoplasms is associated with alteration of these glycoconjugates, and especially that LMP tumors have a different composition of cellular glycoconjugates from that of invasive ovarian carcinoma. 相似文献
98.
S Yamashita K Taniguchi H Morimitsu H Suzu H Kanetake Y Saito Y Yushita T Sakuragi 《Hinyokika kiyo. Acta urologica Japonica》1992,38(5):519-524
Between 1986 and 1989, 14 patients undergoing cystectomy for bladder cancer, in pathological stage high risk pT2 group, pT3-4 and/or with N+ disease, received postoperative adjuvant methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) chemotherapy. Of the 14 patients 10 were alive with no evidence of disease for an average of 41 months. Tumor recurrence was seen in 4 patients (bone in 2, lungs in 1, brain in 1 patient). Of the 4 patients, 3 patients died of cancer progression at an average of 26 months and 1 patient was alive with tumor for 30 months. Their actual survival rate at 64 months was 70%, which was significantly higher than that of the historical control groups (1974-1981: 18%, 1982-1985: 46%). Although postoperative adjuvant M-VAC chemotherapy for invasive bladder cancer seemed effective in this study, a controlled randomized study will be necessary to conclude if it could be of real benefit for these patients. 相似文献
99.
Eiichiro SUGIYAMA Takayoshi IKEDA Hiroshi MAEDA Takeshi MATSUO Masaru MATSUMOTO 《Congenital anomalies》1987,27(2):85-93
Abstract True incidence of this malformation is probably greater than that reported since the definitive diagnosis has been made at autopsy in most cases. Various hypotheses on the pathogenesis of tracheal agenesis have been proposed but they are still controversial.
In this report, we present a case of tracheal agenesis with a broncho-esophageal fistula and discuss the formal genesis. 相似文献
In this report, we present a case of tracheal agenesis with a broncho-esophageal fistula and discuss the formal genesis. 相似文献
100.
This experiment was designed to examine the effects of indomethacin, a potent prostaglandin synthesis inhibitor, on spontaneous mammary tumors in mice. The growth of established mammary tumors and the appearance of new tumors in multiparous SHN mice were significantly suppressed by the subcutaneous implantation of pellets of indomethacin diluted to 1/12 with cholesterol. Furthermore, the same treatment inhibited normal and preneoplastic mammary gland growth in virgin SHN mice. The pattern of estrous cycles, ovarian structure, and plasma prolactin levels were not affected significantly by the treatment. All results have demonstrated that indomethacin inhibits mammary tumorigenesis of mice primarily by route(s) other than the endocrine system under the present experimental conditions. Indomethacin would be the first agent that appears to inhibit the growth of spontaneous mammary tumors of palpable size in mice. 相似文献