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101.
102.
We investigated the patterns of projections from the pulvinar to visual areas V1, V2, V4, and MT, and their relationships to pulvinar subdivisions based on patterns of calbindin (CB) immunostaining and estimates of visual field maps (P(1), P(2) and P(3)). Multiple retrograde tracers were placed into V1, V2, V4, and/or MT in 11 adult macaque monkeys. The inferior pulvinar (PI) was subdivided into medial (PI(M)), posterior (PI(P)), central medial (PI(CM)), and central lateral (PI(CL)) regions, confirming earlier CB studies. The P(1) map includes PI(CL) and the ventromedial portion of the lateral pulvinar (PL), P(2) is found in ventrolateral PL, and P(3) includes PI(P), PI(M), and PI(CM). Projections to areas V1 and V2 were found to be overlapping in P(1) and P(2), but those from P(2) to V2 were denser than those to V1. V2 also received light projections from PI(CM) and, less reliably, from PI(M). Neurons projecting to V4 and MT were more abundant than those projecting to V1 and V2. Those projecting to V4 were observed in P(1), densely in P(2), and also in PI(CM) and PI(P) of P(3). Those projecting to MT were found in P(1)- P(3), with the heaviest projection from P(3). Projections from P(3) to MT and V4 were mainly interdigitated, with the densest to MT arising from PI(M) and the densest to V4 arising from PI(P) and PI(CM). Because the calbindin-rich and -poor regions of P(3) corresponded to differential patterns of cortical connectivity, the results suggest that CB may further delineate functional subdivisions in the pulvinar.  相似文献   
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104.
PURPOSE: We evaluated the success of several techniques for treating urethral obstruction and erosion after a pubovaginal sling procedure. MATERIALS AND METHODS: Between April 1998 and June 1999, 32 women 33 to 79 years old (average age 62) who underwent a pubovaginal sling procedure with various materials were referred for the assessment of urethral obstruction. Patients were evaluated with a urogynecologic history, physical examination, voiding diary, cystoscopy and video urodynamics. Surgical procedures to resolve urethral obstruction were performed transvaginally and the specific techniques used were based on the type of sling material, urethral erosion and concomitant stress incontinence or other urethral pathology. Outcome measures were assessed by disease specific quality of life questionnaires, voiding diary and urogynecologic questionnaire. RESULTS: Preoperatively 30 of the 32 women (93.7%) noticed urge incontinence, 20 (62.5%) performed intermittent self-catheterization, 6 (18.7%) had an indwelling catheter and 3 (9%) complained of concomitant stress urinary incontinence. After the sling takedown 29 patients (93.5%) achieved efficient voiding within week 1 postoperatively. Urge incontinence symptoms resolved in 20 cases (67%) but stress incontinence developed in 3 (9%). Of the 32 women 27 (84%) indicated that continence was much better than before the initial sling procedure. CONCLUSIONS: Managing urethral obstruction after a pubovaginal sling procedure is challenging. Using various techniques based on sling material, urethral erosion and bladder neck integrity a successful outcome is possible in the majority of cases.  相似文献   
105.
胰管损伤是儿童胰脏钝性损伤高死亡率及高致残率的主要原因和决定因素。在确诊了损伤类型和解剖学部位的基础上,必须实施正确的治疗。CT检查不能明确胰管损伤的类型和部位。内镜逆行胰管造影(ERP)是确定患儿胰管状况的可靠手段,并可以对合适的患实施支架植入术以治疗胰管损伤。目前仅有一项报道,对2例钝性创伤患儿应用治疗性ERP加支架植入术治疗胰管损伤。本报道中,作介绍1例11岁的胰管损伤患儿,经ERP术获得诊断并接受内镜下支架植入术。患儿平稳康复并出院。内镜逆行胰管造影可能是胰管破裂的有效诊断和治疗手段。  相似文献   
106.
Monoclonal antibody (mAb) 806 is a novel epidermal growth factor receptor (EGFR) antibody with significant antitumor activity that recognizes a mutant EGFR commonly expressed in glioma known as delta2-7 EGFR (de2-7 EGFR or EGFRvIII) and a subset of the wild-type (wt) EGFR found in cells that overexpress the receptor. We have used two human xenograft mouse models to examine the efficacy of mAb 806 in combination with mAb 528, a prototypical anti-EGFR antibody with similar specificity to cetuximab. Treatment of nude mice, bearing s.c. or i.c. tumor human xenografts expressing the wt or de2-7 EGFR, with mAbs 806 and 528 in combination resulted in additive and in some cases synergistic, antitumor activity. Interestingly, mAb 528 was also effective against xenografts expressing the ligand independent de2-7 EGFR when used as a single agent, showing that its antitumor activity is not merely mediated through inhibition of ligand binding. When used as single agents, neither mAbs 806 or 528 induced down-regulation of the de2-7 EGFR either in vitro or in vivo. In contrast, the combination of antibodies produced a rapid and dramatic decrease in the total cell surface de2-7 EGFR both in vitro and in xenografts. Consistent with this decrease in total cell surface de2-7 EGFR, we observed up-regulation of the cell cycle inhibitor p27(KIP1) and a decrease in tumor cell proliferation as measured by Ki-67 immunostaining when the antibodies were used in combination in vivo. Thus, mAb 806 can synergize with other EGFR-specific antibodies thereby providing a rationale for its translation into the clinic.  相似文献   
107.
108.
The effect of smoking on placental and fetal zinc status   总被引:1,自引:0,他引:1  
Previous studies have reported a cadmium/zinc interaction in cadmium-exposed pregnant animals that results in (1) increased placental cadmium levels, (2) increased placental zinc levels, and (3) decreased placental zinc transport. This study was carried out to determine whether zinc status would be affected in pregnant women exposed to cadmium through cigarette smoke. Atomic absorption spectroscopy was used to determine the levels of cadmium and zinc; 65 pregnant women who smoke and 84 who do not smoke were studied. Our data reveal that increased cadmium levels in pregnant women as the result of smoking increase placental zinc levels and decrease cord red blood cell zinc levels. Significantly higher levels of both cadmium and zinc were found in the placentas of pregnant women who smoke; moreover, stepwise multiple regression showed that maternal whole blood cadmium levels predicted placental zinc levels. In regard to cord blood, a significant 9% decrease in the red blood cell zinc level was observed in infants of mothers who smoke and this decrease was correlated with smoking activity, as evaluated by measuring plasma levels of thiocyanate. Also cord red blood cell zinc levels were found to correlate with placental zinc levels in nonsmokers but not in smokers. Overall, our data show that a cadmium/zinc interaction does take place in the maternal-fetal-placental unit of pregnant women who smoke and results in less favorable zinc status in the infants.  相似文献   
109.
In an attempt to identify oocytes at risk for polypronuclear fertilization, follicular fluids were obtained retrospectively that contained oocytes that fertilized normally and abnormally. Whenever possible, each patient served as her own control during the same stimulation cycle. Twenty-six of 169 patients had oocytes that became polypronuclear, and of those 26, 21 had oocytes that fertilized and cleaved normally. Follicular fluids were analyzed for estradiol, progesterone, androstenedione, transferrin, and insulin. Insulin levels were noted to be significantly elevated (P less than 0.05) in the polypronuclear group when compropose that insulin, a known growth factor for granulosa cells cultured in vitro, when present in excessive concentrations may predispose to polypronuclear fertilization.  相似文献   
110.
Six phakic patients with unilateral corneal edema and clinically normal-appearing fellow eyes were examined with specular microscopy and found to have endothelial pleomorphism and reduced cell counts in the nonedematous cornea. None of these patients had any previous eye disease, trauma, inflammation, or surgery. Clinically unrecognized endothelial disease was proposed as a cause for the unilateral corneal edema and was verified by light and electron microscopic studies in five patients. These pathologic findings vary somewhat from those found in Fuchs' dystrophy and may represent either a variant or a form of endothelial cell degeneration of as yet undetermined etiology. Our studies suggest that this condition is not detectable in the nonedematous cornea by standard high magnification biomicroscopy and requires the use of the clinical specular microscope to confirm the diagnosis in suspected cases.  相似文献   
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