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101.
Michio Maeta Hiroaki Saito Akira Kondo Hiroshi Yamashiro Syunichi Tsujitani Masahide Ikeguchi Nobuaki Kaibara 《Gastric cancer》1998,1(1):57-63
Background.
In Japan, much attention has recently been paid to super-extended paraaortic lymphadenectomy (PAL) for the treatment of advanced
gastric cancer. However, it has been reported that PAL is associated with increased morbidity and mortality, as compared to
conventional extended lymphadenectomy (D2 or D3). Therefore, an analysis of the effects of PAL on perioperative changes in
the biological responses of patients essential for determining the potential utility of this procedure.
Methods.
The current non-randomized prospective study included evaluations of perioperative changes in parameters of surgical stress
(series I; serum levels of antidiuretic hormone, interleukin-6, trypsin, and phospholipase A
2
) and immunocompetence (series II; phytohemagglutinin- and concanavalin A-induced blastogenesis, activity of natural killer
cells and the ratio of CD4 cells to CD8 cells) in patients with advanced gastric cancer (T3 or T4), comparing groups treated
with D3 plus PAL (
n
= 12) and D3 (
n
= 13), and a control group with early gastric cancer (
n
= 16) treated with D1 lymphadenectomy (perigastric N1 nodes) between April 1995 and April 1997.
Results.
The duration of surgery and the amount of blood lost were longer and greater in the D3 plus PAL group than in the D3 and D1
groups. D3 plus PAL and D3 were associated with significant postoperative increases in parameters of surgical stress, as well
as with significant postoperative immunosuppression, compared to results with D1. However, there were no significant differences
in the respective parameters between the D3 plus PAL and D3 groups.
Conclusions.
Our results indicate that there are no essential differences in patients' biological responses between D3 plus PAL and D3
lymphadenectomy. It appears that PAL-associated morbidity can be minimized by very careful manipulation during the dissection
of paraaortic lymph nodes.
Received for publication on Feb. 10, 1998; accepted on Jun. 3, 1998 相似文献
102.
Phenotypic shift in human differentiated gastric cancers from gastric to intestinal epithelial cell type during disease progression 总被引:3,自引:1,他引:3
Akemi Yoshikawa Ken-ichi Inada Takasuke Yamachika Nobuyuki Shimizu Michio Kaminishi Masae Tatematsu 《Gastric cancer》1998,1(2):134-141
Background. The phenotypic expression of tumor cells is widely thought to resemble that of the tissue of origin. In the present study,
to assess phenotypic changes that occur with disease progression, we investigated human differentiated gastric cancers at
different depths of invasion for component cancer cell types.
Methods. Using a combined mucin histochemical and immunohistochemical approach, we classified surgical specimens of 301 differentiated
gastric cancers into three types: gastric epithelial cell (G) type, intestinal epithelial cell (I) type and mixed gastric
and intestinal (GI) type, according to the phenotypic differentiation of the component cancer cells. The relation between
the phenotypic type of cancer and their depth of invasion was evaluated.
Results. The proportion of G type cancers was 41.4% in early (tumor invasion of mucosa or submucosa) cases, decreasing to 22.2% in
advanced (tumor invasion of muscularis propia or deeper) cases, whereas the proportion of I type cancers increased with progressive
disease from 23.5% to 31.1% (P < 0.01). Cancers invading the subserosa or deeper included more I type cases and fewer G type than cancers limited to the
mucosa (P < 0.01). In most cases of each phenotypic type, intestinal metaplasia was recognized in the surrounding background mucosa,
but no clear relation was shown between the phenotype of cancers and the degree of intestinal metaplasia in the background
mucosa, suggesting that intestinal metaplasia is not always a preneoplastic lesion.
Conclusions. A phenotypic shift from G to I type expression was observed with the progression of human differentiated gastric cancers.
Intestinalization may occur independently in cancerous and noncancerous gastric mucosa.
Received for publication on May 1, 1998; accepted on Oct. 22, 1998 相似文献
103.
104.
Correlation between bone marrow edema and collapse of the femoral head in steroid-induced osteonecrosis 总被引:26,自引:0,他引:26
Iida S Harada Y Shimizu K Sakamoto M Ikenoue S Akita T Kitahara H Moriya H 《AJR. American journal of roentgenology》2000,174(3):735-743
OBJECTIVE: The purpose of this study was to clarify whether bone marrow edema is detectable on initial MR imaging of steroid-induced osteonecrosis of the femoral head. SUBJECTS AND METHODS: Forty-eight hips with osteonecrosis were examined consecutively with MR imaging and radiography. In a previously reported screening program, osteonecrosis was diagnosed on MR imaging when subchondral bands of abnormal signals were present. In the screening program, the MR images of 200 hips of 100 patients receiving high-dose steroid therapy were examined prospectively. Subchondral bands were detected in 48 hips at a mean of 14 weeks after the initiation of steroid therapy. RESULTS: On follow-up MR imaging of 47 hips (one hip excluded) bone marrow edema was initially observed in 13 hips after the onset of hip pain. MR imaging of the remaining 34 hips did not reveal bone marrow edema and the patients were all asymptomatic. MR imaging of 31 of the 34 hips continued to show subchondral bands and MR imaging of the other three hips indicated that the subchondral bands had disappeared. When bone marrow edema was detectable, abnormal findings on radiography were slight but 11 (85%) of the 13 hips progressed to advanced osteonecrosis. Bone marrow edema was highly correlated with the subsequent collapse of the femoral head (p<0.0001). CONCLUSION: Bone marrow edema was not present on initial MR imaging of osteonecrosis. Bone marrow edema should be considered a marker for potential progression to advanced osteonecrosis, and careful examinations for osteonecrosis are necessary when bone marrow edema is seen. 相似文献
105.
Leiomyosarcoma of the scrotum is a rare tumor. Up to 1999, only 29 cases have been reported in the literature worldwide. A 27-year-old man presented with a mass on the left side of the scrotum which had been painless and had gradually enlarged over the previous 10 years. During the following 3 months, however, it became painful and he was then referred to our hospital. Physical examination revealed a solid mass on the left side of the scrotum, measuring 7 cm in diameter, which was not adhering to the testis or to the vas deferens. The tumor was surgically resected. The histological examination confirmed the diagnosis of well differentiated leiomyosarcoma. Adjuvant therapy was considered unnecessary. The follow-up at 41 months revealed no local recurrence or distant metastasis. 相似文献
106.
Accelerated growth signals and low tumor-infiltrating lymphocyte levels predict poor outcome in T4 esophageal squamous cell carcinoma 总被引:10,自引:0,他引:10
Yasunaga M Tabira Y Nakano K Iida S Ichimaru N Nagamoto N Sakaguchi T 《The Annals of thoracic surgery》2000,70(5):1634-1640
BACKGROUND: Little is known about the biological nature of T4 esophageal carcinoma growth signals and host defenses. METHODS: Paraffin-embedded sections from 78 patients with T2 to T4 esophageal squamous cell carcinoma who underwent operation were analyzed with immunohistochemistry. RESULTS: Positive cyclin A showed a significantly greater increase in T4 tumors than in those of other stages, and negative p27 showed a significantly greater decrease in T4 tumors than in large T3 stage tumors (tumor size > or = 4.0 cm). Patients with low-grade tumor-infiltrating lymphocyte (TIL) density showed a significantly greater decrease in T4 than in T2. The combination of p27 and cyclin A was a significant independent prognostic factor among T and N factors in multivariate analysis. TIL density was an independent prognostic factor among immunonutritional variables such as serum albumin concentration and the number of total blood lymphocytes. CONCLUSIONS: T4 esophageal squamous cell carcinoma has a poor prognosis, which is associated with increased p27-negative and cyclin A-positive growth signals in the tumor and with low TIL density in the host. 相似文献
107.
BACKGROUND: Systemic dexmedetomidine (DXM) attenuates the cerebral vasodilation induced by hypercapnia and decreases the cerebral blood flow response to hypoxia. We determined whether lumbar intrathecal DXM affected the cerebrovascular reactivity to hypercapnia and hypoxia. METHODS: Rabbits (n = 55) anesthetized with pentobarbital were prepared for measurement of pial vessel diameters using a closed cranial window preparation. The first study evaluated the response to hypercapnia after intrathecal administration of DXM (2 microg/kg; n = 7) or normal saline (n = 8). The second evaluated the response to hypercapnia after intrathecal DXM in the presence of yohimbine (20 microg/kg followed by DXM 2 microg/kg; n = 7). The third evaluated the response to mild or moderate hypoxia after intrathecal DXM (2 microg/kg; n = 7) or normal saline (n = 7). The hypercapnic responses were also examined in the presence of systemic DXM (2, 10 microg/kg; n = 6), topical DXM (10-8 m, 10-6 m; n = 6) and of intrathecal clonidine (2 microg/kg; n = 7). RESULTS: The pial arteriolar dilator response to hypercapnia was significantly attenuated after intrathecal administration of DXM. Pretreatment with yohimbine completely blocked the decreased reactivity to hypercapnia. Intrathecal clonidine, although less than DXM, also attenuate the hypercapnic response. Intrathecal DXM did not affect the vasodilation of pial arterioles induced by mild or moderate hypoxia. The systemic DXM 10 microg/kg and topical DXM 10-6 m, but not systemic 2 microg/kg and topical 10-8 m, attenuated hypercapnic vasodilation of pial arterioles. CONCLUSIONS: The presence of alpha2-adrenoceptor agonist administered intrathecally into the lumbar spinal region attenuates hypercapnic but not hypoxic cerebral vasodilation, probably via a stimulation of central alpha2-adrenergic receptors of the central nervous system. 相似文献
108.
Ohno Ken; Araki Naohiro; Yanase Toshihiko; Nawata Hajime; Iida Mitsuru 《Toxicological sciences》2005,83(2):406
The following sentences should have read: Results, Reproducibility 相似文献
109.
110.
Use of spiral computerized tomography angiography in patients with subarachnoid hemorrhage in whom subtraction angiography did not reveal cerebral aneurysms 总被引:14,自引:0,他引:14
OBJECT: Patients with subarachnoid hemorrhage (SAH) in whom angiography does not demonstrate diagnostic findings sometimes suffer recurrent disease and actually harbor undetected cerebral aneurysms. The management strategy for such cases remains controversial, but technological advances in spiral computerized tomography (CT) angiography are changing the picture. The purpose of this prospective study was to examine how spiral CT angiography can contribute to the detection of cerebral aneurysms that cannot be visualized on angiography. METHODS: In 134 consecutive patients with SAH, a prospective search for the source of bleeding was performed using digital subtraction (DS) and spiral CT angiography. In 21 patients in whom initial DS angiography yielded no diagnostic findings, spiral CT angiography was performed within 3 days. Patients in whom CT angiography provided no diagnostic results underwent second and third DS angiography sessions after approximately 2 weeks and 6 months, respectively. Six patients with perimesencephalic SAH were included in the 21 cases. Six of the other 15 patients had small cerebral aneurysms detectable by spiral CT angiography, five involving the anterior communicating artery and one the middle cerebral artery. Two patients in whom initial angiograms did not demonstrate diagnostic findings proved to have a ruptured dissecting aneurysm of the vertebral artery; in one case this was revealed at autopsy and in the other during the second DS angiography session. A third DS angiography session revealed no diagnostic results in 13 patients. CONCLUSIONS: Spiral CT angiography was useful in the detection of cerebral aneurysms in patients with SAH in whom angiography revealed no diagnostic findings. Anterior communicating artery aneurysms are generally well hidden in these types of SAH cases. A repeated angiography session was warranted in patients with nonperimesencephalic SAH and in whom initial angiography revealed no diagnostic findings, although a third session was thought to be superfluous. 相似文献