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排序方式: 共有8811条查询结果,搜索用时 15 毫秒
111.
Hikoyoshi Chin Hideo Matsui Akira Mitsuhashi Kohichi Nagao Souei Sekiya 《Gynecologic oncology》1998,71(3):469-475
Primary carcinoma of the fallopian tube is extremely rare and the preoperative diagnosis is often misdiagnosed as an ovarian carcinoma. We report a patient with primary carcinoma of the fallopian tube, strongly suspected preoperatively on the basis of characteristic clinical symptoms, elevated CA125 levels, and transvaginal sonography, computed tomography, and magnetic resonance imaging findings. The histology of fallopian tube carcinoma was demonstrated as transitional cell carcinoma. Extensive review of the literature showed that our case seemed to be the 14th case of primary transitional cell carcinoma of the fallopian tube. 相似文献
112.
WF Paterson E McNeill S Reid AS Hollman MD Donaldson 《Archives of disease in childhood》1998,79(4):323-327
OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment. 相似文献
113.
Oberyszyn TM; Conti CJ; Ross MS; Oberyszyn AS; Tober KL; Rackoff AI; Robertson FM 《Carcinogenesis》1998,19(3):445-455
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate
adherence of leukocytes to vascular endothelium and the associated ligand,
intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2
integrin proteins to allow transendothelial migration of leukocytes into
sites of inflammation. The present study examines the function of these
proteins in a murine model of acute cutaneous inflammation induced
following topical application of 12-O- tetradecanoylphorbol-13-acetate
(TPA) to the dorsal epidermis of SENCAR mice and in a model of skin
multistage carcinogenesis. At 24 h following topical application of TPA to
the dorsal epidermis of mice, dermal leukocytes expressed higher levels of
beta2 integrin protein compared with the lower levels of beta2 integrin
protein expression by peripheral blood leukocytes. ICAM-1 protein was
localized to epidermal keratinocytes and vascular endothelium in
TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.)
injection of either 50 microg anti-beta2 integrin antibody alone or in
combination with anti-ICAM-1 antibody significantly inhibited both
TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and
myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P
< 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but
had no effect on TPA-induced epidermal hyperplasia. In addition, injection
of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in
combination with anti-beta2 integrin antibody (P < 0.001) significantly
inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8-
OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2
integrin/ICAM-1 adhesion molecules work in concert to regulate migration,
retention and functional activation of leukocytes within the dermis during
TPA-induced skin inflammation and within stromal tissue of papillomas that
form during multi-stage carcinogenesis. Agents that inhibit these
receptor/ligand interactions may be useful in defining the roles of
specific cell populations in cutaneous inflammation and multistage
carcinogenesis and may also have potential as anti-promoting and
anti-progression agents.
相似文献
114.
Mutation of the p53 tumor suppressor gene in spontaneously occurring osteosarcomas of the dog 总被引:8,自引:0,他引:8
Inactivation of the p53 tumor suppressor gene has been implicated in the
pathogenesis of numerous human cancers, including osteosarcomas.
Appendicular osteosarcomas of the dog appear to be a good model for their
human equivalent with regard to biologic behavior, epidemiology and
histopathology. We individually screened exons 5-8 of the p53 gene for
mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to
compare the role of this gene in human and canine osteosarcoma
tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with
one tumor possessing two mutations within different exons. Of these, seven
were missense mutations and the eighth was a 'silent' mutation potentially
affecting the exon 6-7 splicing region. Five of the missense mutations were
located in highly conserved regions IV and V, while another corresponded
with the highly conserved codon 220 mutational hotspot located outside the
conserved domains. The locations and types of mutations were nearly
identical to those reported in human cancer. These findings provide strong
evidence of the involvement of p53 mutations in the development of canine
appendicular osteosarcomas. Canine osteosarcomas appear to be a promising
model for their human equivalent on a clinical, pathologic, and molecular
level.
相似文献
115.
One hundred patients of Diabetes Mellitus (70 with and 30 without clinical somatic neuropathy) were studied to correlate clinical severity with the magnitude of nerve conduction abnormalities. Age range was 10-79 years (mean 49) with equal number of males and females. Incidence of neuropathy was more in patients over 40 years of age (60 out of 70 patients) with duration of disease over two years (78.33%). The grades of severity were mild in 22 (31.33%), moderate in 25 (35.71%) and severe in 23 (32.86%) patients. Nerve conduction studies were carried out in 48 (27 with and 21 without clinical neuropathy) patients, using the apparatus Dantec (Cantata TM). The nerves (median, peroneal and sural) were stimulated at two points and the recording of latency; amplitude (micro V) and motor and sensory nerve conduction velocities (m/s) were done under identical environmental conditions. Sensory nerve conduction velocity was more affected than motor velocity. In the 21 patients without clinical neuropathy, 14 showed abnormalities indicating early involvement of peripheral nerves. Reduction of motor nerve conduction velocity was more in patients with moderate and severe grades. The reduction was more in lower than in upper limbs. Nerve conduction abnormality helps in diagnosis in diabetic neuropathy even in preclinical state and correlates with severity, in clinical neuropathy.KEY WORDS: Diabetic neuropathy, Nerve conduction abnormality, Peripheral neuropathy 相似文献
116.
Khan AM Stanley BG Bozzetti L Chin C Stivers C Currás-Collazo MC 《The Journal of comparative neurology》2000,428(3):428-449
Glutamate (Glu), a major excitatory neurotransmitter within the hypothalamus and thalamus, acts upon many receptors, including the N-methyl-D-aspartate (NMDA) subtype. Abundant evidence suggests that variations in the subunit composition of NMDA receptors (NMDA-Rs) contribute to differences in Glu's immediate electrophysiological effects as well as to the patterns of signal transduction cascades it triggers to mediate long-term changes in neuronal function. We have previously shown that hypothalamic NMDA-Rs containing the NR2B subunit may be involved in the control of eating as well as in the mediation of physiological responses to osmotic stimuli. To broaden our understanding of diencephalic NMDA-R participation in other functions, we localized the NR2B subunit in the diencephalon of the adult male rat using immunoperoxidase, immunogold, and immunofluorescence techniques and an affinity-purified polyclonal antibody specific for the NR2B subunit of the NMDA-R. In addition, we used a monoclonal NR2B antibody with immunoperoxidase detection to confirm the NR2B distribution seen with the polyclonal antibody. In the hypothalamus, the highest levels of NR2B immunoreactivity (-ir) were found in the magnocellular neurosecretory system, including the paraventricular and supraoptic nuclei. A new finding was that intense NR2B-ir was present within perivascular "accessory" magnocellular groups of this system, including the nucleus circularis, anterior fornical nucleus, and scattered clusters of lateral hypothalamic cells apposed to blood vessels. Robust NR2B-ir was also present within the arcuate nucleus, the median eminence, and the tuberal nucleus, and light immunostaining was found in all other hypothalamic nuclei examined. In the thalamus, the highest NR2B-ir was observed in the medial habenula and the anterodorsal, paraventricular, rhomboid, reticular, and dorsal lateral geniculate nuclei. As in the hypothalamus, all thalamic nuclei examined displayed at least light immunostaining for this subunit. Control sections, including those incubated with the polyclonal NR2B antibody preadsorbed with its fusion protein, were virtually devoid of immunostaining. This demonstration that the NR2B subunit of the NMDA-R is widely distributed in the diencephalon, implicates it in a wide variety of functions, and provides a useful anatomical framework for establishing a comprehensive map of Glu receptor populations within this major subdivision of the brain. 相似文献
117.
Parker JC McPherson RK Andrews KM Levy CB Dubins JS Chin JE Perry PV Hulin B Perry DA Inagaki T Dekker KA Tachikawa K Sugie Y Treadway JL 《Diabetes》2000,49(12):2079-2086
Peptidic glucagon antagonists have been shown to lower blood glucose levels in diabetic models (1-3), but attempts to identify small molecular weight glucagon receptor-binding antagonists have met with little success. Skyrin, a fungal bisanthroquinone, exhibits functional glucagon antagonism by uncoupling the glucagon receptor from adenylate cyclase activation in rat liver membranes (1). We have examined the effects of skyrin on cells transfected with the human glucagon receptor and on isolated rat and human hepatocytes. The skyrin used was isolated from Talaromyces wortmanni American Type Culture Collection 10517. In rat hepatocytes, skyrin (30 micromol/l) inhibited glucagon-stimulated cAMP production (53%) and glucose output (IC50 56 micromol/l). There was no detectable effect on epinephrine or glucagon-like peptide 1 (GLP-1) stimulation of these parameters, which demonstrates skyrin's selective activity. Skyrin was also evaluated in primary cultures of human hepatocytes. Unlike cell lines, which are largely unresponsive to glucagon, primary human hepatocytes exhibited glucagon-dependent cAMP production for 14 days in culture (EC50 10 nmol/l). Skyrin (10 micromol/l) markedly reduced glucagon-stimulated cAMP production (55%) and glycogenolysis (27%) in human hepatocytes. The inhibition of glucagon stimulation was a specific property displayed by skyrin and oxyskyrin but not shared by other bisanthroquinones. Skyrin is the first small molecular weight nonpeptidic agent demonstrated to interfere with the coupling of glucagon to adenylate cyclase independent of binding to the glucagon receptor. The data presented in this study indicate that functional uncoupling of the human glucagon receptor from cAMP production results in metabolic effects that could reduce hepatocyte glucose production and hence alleviate diabetic hyperglycemia. 相似文献
118.
Chin KR Altman DT Altman GT Mitchell TM Tomford WW Lhowe DW 《Clinical orthopaedics and related research》2000,(373):218-226
The authors studied 10 consecutive patients with closed femoral shaft or supracondylar fractures who were nonambulatory and who were treated by reamed retrograde intramedullary nailing via an intercondylar notch approach. The study consisted of five women and five men with an average age of 60.7 years (range, 40-89 years). Six patients had spinal cord lesions, one had a brain injury, one had cerebral palsy, one had multiple sclerosis, and one had progressive myelopathy. Three fractures were supracondylar, and seven fractures involved the mid-distal diaphysis. The average time of surgery was 110 minutes (range, 70-225 minutes) with an average estimated blood loss of 288 mL (range, 150-400 mL). There were two postoperative deaths (at 15 days and 2 months, respectively) after the procedure that were attributable to pneumonia. The remaining eight patients were observed for an average of 13 months (range, 6-20 months) after surgery. All fractures healed as evaluated radiographically. Retrograde intramedullary nailing is a simple, safe, and effective alternative to nonoperative treatment for femoral shaft or supracondylar fractures in patients who are nonambulatory. Stabilization by this method allows fracture healing and rapid return of patients to their previous level of function. There were no nonunions, malunions, significant shortening, implant failure, or wound infections. 相似文献
119.
Cysts arising from the III and IV pharyngeal pouches, although uncommon, are typical in their presentation. They occur in neonates, invariably in the left anterior neck and cause respiratory distress. Excision of the cyst with ligation of the tract at the level of the pyriform sinus is curative. 相似文献
120.