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31.
Between 1970 and 1991 the authors examined 466 cases with Eales' disease. 359 eyes of 295 of these 466 cases received photocoagulation treatment. The mean age was 30.4, ranging between 14 and 55 years. Ten eyes with persistent vitreous hemorrhage underwent pars plana vitrectomy before photocoagulation. 210 eyes were treated with xenon arc, 135 with argon laser, 12 with krypton laser and two with yellow dye laser. Hypoxic areas and retinal neovascularizations were closed completely in 298 eyes. In 21 eyes with elevated neovascularizations intruding into the vitreous cavity feeder vessel photocoagulation was used. 24 eyes with disc neovascularization were treated with panretinal photocoagulation. 12 eyes with branch vein occlusion and four eyes with central vein occlusion received photocoagulation treatment to areas of non-perfusion and retinal neovascularization. At a mean follow-up of 43 months, seven new retinal neovascularizations and three new disc neovascularizations developed in eyes which previously had received photocoagulation for retinal neovascularization and hypoxia. Nine out of 21 eyes with elevated neovascularizations developed vitreous hemorrhage. Disc neovascularization resolved completely in 13 out of 24 eyes, it partially regressed in eight eyes and did not respond to treatment in three eyes. The visual acuities were improved in 12.3%, maintained in 77.4% and deteriorated in 10.3% of the eyes after treatment. Periodic follow-up and early photocoagulation treatment is useful in stabilizing the retinal lesions and in maintaining functional levels of vision in Eales' disease.  相似文献   
32.
The effect of capsaicin-induced stimulation of afferent neurons on peristalsis and the possible neural mediators involved in this action were examined in the guinea-pig isolated ileum. The intraluminal pressure threshold for eliciting peristaltic waves was used to quantify facilitation (decrease in threshold) or inhibition (increase in threshold) of peristalsis. Capsaicin (0.1–1 M) caused an initial short-lasting stimulation of peristalsis followed by a prolonged inhibition of peristaltic activity. Capsaicin (1 M) was ineffective when the gut segments had been pretreated with 3.3 M capsaicin, which is indicative of an afferent neuron-dependent action of the drug. In contrast, the abolition of peristalsis caused by a high concentration of capsaicin (33 M) was fully reversible on removal and reproducible on readministration of capsaicin, a feature characteristic of a nonspecific depression of smooth muscle excitability. Baseline peristalsis and the excitatory/inhibitory effect of capsaicin (1 M) on peristalsis remained unaltered by a combination of the tachykinin NK1 receptor antagonist ( + )-(2S, 3S)-3-(2-methoxybenzylamino)-2-phenyl piperidine (CP-99,994; 0.3 M) and the tachykinin NK2 receptor antagonist L(-)-N-methyl-N[4-acetylamino-4-phenyl-piperidino-2-(3,4-dichlorophenyl)butyl]-benzamide (SR-48,968; 0.1 M). Further experiments, performed in the presence of a low concentration of atropine (10 nM) showed that the catcitonin gene-related peptide (CGRP) antagonist human -catcitonin gene-related peptide (8–37) [hCGRP (8–37); 10 M] attenuated the delayed inhibitory effect of capsaicin on peristalsis, but did not influence baseline peristaltic activity and the capsaicin-induced facilitation of peristalsis. Blockade of nitric oxide (NO) synthesis by N G-nitro-l-arginine methylester (l-NAME, 300 M) facilitated baseline peristaltic activity and reduced the delayed inhibition of peristalsis caused by capsaicin (1 M) without affecting the initial peristalsis-stimulating action of capsaicin. The effects of l-NAME were prevented by l-arginine (1 mM). The data of the current study indicate that capsaicin-sensitive afferent neurons do not participate in the neural pathways subserving peristalsis in the guinea-pig small intestine, but modulate peristaltic activity upon stimulation with capsaicin. The initial stimulant action of capsaicin on peristalsis is independent of tachykinins acting via NK1 or NK2 receptors, while the delayed capsaicin-induced depression of peristalsis involves CGRP and NO.  相似文献   
33.
BACKGROUND: Radical resection using deep hypothermic circulatory arrest improves the survival of patients with transvenous intracardiac tumor extension of renal cell carcinomas. A less invasive surgical approach avoiding deep hypothermia, circulatory arrest, and cross-clamping of the aorta is presented. METHODS: Between 1987 and 1999, 12 patients (mean age 57+/-8 years) underwent resection of a renal cell carcinoma extending into the right atrium, right ventricle, or pulmonary arteries. After median sterno-laparotomy, normothermic cardiopulmonary bypass is used cannulating the ascending aorta, superior caval vein, and inferior caval vein below the renal veins. The tumor and the corresponding kidney are radically excised, including the renal vein. Tumor fragments from the inferior caval vein, the right heart, and pulmonary arteries are removed either on the fibrillating or beating heart. RESULTS: Operative mortality was 0%. Mean cardiopulmonary bypass time was 53+/-27 minutes (median 36; range 32-110 minutes). Mean blood loss per patient was 1200 mL. Mean duration of postoperative mechanical ventilation was 36+/-12 hours (median 36; range 30-77 hours), mean intensive care stay 5.5+/-5 days (median 3; range 1-48 days), and mean duration of hospitalization 22+/-12 days (median 21; range 10-58 days). All patients were discharged home. Patients with multiple tumor manifestations outside the cardiovascular systems died within 9 months after the operation. CONCLUSIONS: The use of normothermic cardiopulmonary bypass is a less invasive method for radical resection of renal cell carcinoma with intracardiac tumor extension. Radical resection does not improve survival in patients with multiple distant metastases.  相似文献   
34.
In many diseases, tissue hypoxia occurs in conjunction with other inflammatory processes. Since previous studies have demonstrated a role for leukocytes in ischemia/reperfusion injury, we hypothesized that endothelial hypoxia may "superinduce" expression of an important leukocyte adhesion molecule, E-selectin (ELAM-1, CD62E). Bovine aortic endothelial monolayers were exposed to hypoxia in the presence or absence of tumor-necrosis factor alpha (TNF-alpha) or lipopolysaccharide (LPS). Cell surface E-selectin was quantitated by whole cell ELISA or by immunoprecipitation using polyclonal anti-E-selectin sera. Endothelial mRNA levels were assessed using ribonuclease protection assays. Hypoxia alone did not induce endothelial E-selectin expression. However, enhanced induction of E-selectin was observed with the combination of hypoxia and TNF-alpha (270% increase over normoxia and TNF-alpha) or hypoxia and LPS (190% increase over normoxia and LPS). These studies revealed that a mechanism for such enhancement may be hypoxia-elicited decrements in endothelial intracellular levels of cAMP (<50% compared with normoxia). Addition of forskolin and isobutyl-methyl-xanthine during hypoxia resulted in reversal of cAMP decreases and a loss of enhanced E-selectin surface expression with the combination of TNF-alpha and hypoxia. We conclude that endothelial hypoxia may provide a novel signal for superinduction of E-selectin during states of inflammation.  相似文献   
35.
Parts I-III of this series used psychometric assessment of motor performance in psychiatric patients and indicated a "psychotic-motor syndrome" (PMS) in schizophrenic and affective psychoses, which was not found in "neurotic"/reactive or healthy persons. Part IV yielded signs of concomitant brain dysfunction in these patients, demonstrated by EEG mapping as well as other (SPECT/PET) neuroimaging methods. Apart from this "basic science" interest into the pathophysiology of endogenous psychoses we engaged in the development of motor training programs using the PMS as "target" syndrome. We hypothesized, that motor training would not only improve disturbed motor behaviour, but ameliorate other symptoms of psychopathology also. These assumptions were supported in the first two independent studies involving n = 45 and n = 31 ICD-9 mono- and/or bipolar endogenous depressed patients, respectively (the studies on schizophrenic patients being reported finally as part VI of this series, along with the final version of our modified motor test battery). Examples of the motor training programs are provided in this paper, although the final version of the complete programs will be published separately for space reasons and for better availability for routine clinical use.  相似文献   
36.
目的:研究高强度聚焦超声(HIFU)治疗大肠癌肝转移病灶的安全性和有效性.方法:18例大肠癌术后肝转移患者31个病灶行HIFU治疗,观察患者生命体征、主要脏器功能、影像学检查(CT或MRI等)、并发症和肿瘤转归的情况.结果:所有患者生命体征平稳,肝、肾功能正常,平均随访16.1个月(6~38个月),失访2例,生存13例,12、18个月生存率分别为83.3%和66.7%,中位生存期16个月;随访25个病灶中,17个肿瘤块缩小超过50%,有5例出现新的转移灶,8例出现皮肤浅Ⅱ度烧伤.结论:HIFU治疗是一种安全、有效和非侵入性治疗大肠癌肝转移病灶的手段.  相似文献   
37.
目的 探讨两种微角膜刀所制角膜瓣对LASIK术后角膜循规性散光的影响。方法 循规性近视散光患者 96人 ( 180眼 )随机分为Ⅰ、Ⅱ两组 ,分别采用MoriaLSK -One平推式气动微角膜刀和MoriaM 2旋转式微角膜刀制做角膜瓣 ,然后进行激光手术。术后 6个月观察患者的角膜散光及角膜散光轴的变化。结果 术后 6个月 ,Ⅰ组、Ⅱ组角膜散光值分别为 0 3 6± 0 13D和 0 5 2±0 0 9D ,与术前相比 ,分别下降 1 3 5± 0 11D ,1 0 8± 0 10D ,差异显著 (P <0 0 1)。而散光轴无明显改变。结论 与MoriaLSK -One平推式气动微角膜刀相比 ,MoriaM 2旋转式微角膜刀所制角膜瓣有产生循规性角膜散光的趋势  相似文献   
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39.
It has been demonstrated recently in several solid tumors that thrombocytosis at diagnosis may correlate with tumor invasion, metastatic progression and worse outcome. Several details of the pathomechanism of the relationship of thrombocytosis and cancer have been elucidated; however, the complete process is not clearly understood. Several hypotheses have been proposed. Recently, it was suggested that in ovarian cancer elevated IL-6 production by the tumor may induce increased megakaryopoiesis via hepatic thrombopoietin production leading to thrombocytosis. The importance of the prognostic power of elevated platelet count is still debated in gastrointestinal cancer. The aims of this review were to evaluate the prognostic significance of thrombocytosis in gastrointestinal tumors, to see whether clinical practice confirmed the hypotheses and to reveal the causes of the inconsistent findings.  相似文献   
40.
Radiological evaluation of internal abdominal hernias.   总被引:1,自引:0,他引:1  
An internal abdominal herniation is the protrusion of a viscus through a normal or abnormal mesenteric or peritoneal aperture. Internal abdominal herniations can either be acquired through a trauma or surgical procedure, or constitutional and related to congenital peritoneal defects. Paraduodenal hernias are the most common type of internal abdominal hernias, accounting for over one-half of reported cases, and thus are a significant clinical entity. Other internal hernias include pericecal, transmesenteric, transomental, intersigmoid, supravesical hernias and herniation through the foramen of Winslow. Because internal abdominal herniations are rare, their diagnosis remains a challenge for both the clinician and the radiologist. Symptoms of internal abdominal herniations are nonspecific. We present our experience with the radiological evaluation of internal abdominal herniations and review the main radiologic findings on barium as well as computed tomography studies.  相似文献   
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