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21.
Zusammenfassung Bei der ophthalmoskopischen Untersuchung des hinteren Augenpols sieht man manchmal loch- und cystenähnliche Befunde. Sie kommen durch Veränderungen der Netzhaut, des Pigmentepithels oder der Bruchschen Membran zustande; erst bei der Untersuchung mit dem Goldmannschen Kontaktglas oder mit dem Hrubyschen Vorsatzglas an der Spaltlampe kann man sie von Löchern und Cysten der Netzhaut sicher unterscheiden. Die Kenntnis dieser Befunde ist bei der Begutachtung von Sehstörungen wichtig.
Summary Sometimes at the ophthalmoscopy of the posterior pole of the eye we see findings resembling holes or cysts of the retina. They result from changes of the retina, pigment epithelium or Bruchs membran; at the slitlamp examination with Goldmann's contact lens or Hruby's pre-set lens only they are certainly distinguishable from holes and cysts of the retina. The knowledge of it is important for the judgement of visual disturbances.


Auszugsweise vorgetragen in der 10. Jahreshauptversammlung der Österreichischen Ophthalmologischen Gesellschaft (Wien, 26. u. 27. Mai 1967).  相似文献   
22.
Zusammenfassung Mit dem Goldmannschen Dreispiegelkontaktglas wurde der Verlauf der vorderen Glaskörpergrenzschicht hinter den Zonulafasern und im Bereich des Ciliarkörpers and der Spaltlampe untersucht. Dabei konnten verschiedene Formen der vorderen retrozonulären und ciliaren Glaskörperabhebung festgestellt werden.
Summary The course of the anterior limiting membran of the vitreous behind the zonular fibers and the area of the ciliary body was examined byGoldmann's three-mirror contact glass and slitlamp. It was possible to discern different forms of the anterior retrozonular and ciliar detachment of the vitreous body.


Mit 12 Textabbildungen  相似文献   
23.
We studied the usefulness of a p63/P504S immunostain "cocktail" in evaluation of prostate biopsy specimens containing atypical acini suspicious for adenocarcinoma (AASA), high-grade prostatic intraepithelial neoplasia (HPIN), and small foci of adenocarcinoma and tested the sensitivity and specificity of the immunostain with tissue microarrays (TMAs) constructed from prostatectomy and lymphadenectomy specimens. We selected 40 cases containing a focus of adenocarcinoma (14 cases), AASA (7 cases), AASA with HPIN (7 cases), HPIN (6 cases), and atypical favor benign (6 cases). After p63/P504S immunostaining, 13 cases (33%) were reclassified: AASA with HPIN to HPIN only in 5 cases (13%), atypical favor benign to benign in 4 cases (10%), AASA to adenocarcinoma in 2 cases (5%), and atypical favor benign to AASA and atypical favor benign to HPIN in 1 case (3%) each. The diagnosis of adenocarcinoma was supported by immunostain in 14 cases. In TMA studies, the p63/P504S immunostain for adenocarcinoma and HPIN had sensitivity values of 97.2% and 86.2%, respectively, and specificity values of 99.7% and 81.6%, respectively. P504S stained 64 (74%) of 87 cores of metastatic cancers, and no p63-positive cells were identified in the metastases. The p63/P504S immunohistochemical stain is a sensitive, specific marker for prostatic adenocarcinoma and HPIN and useful in the evaluation of AASA in biopsy specimens.  相似文献   
24.
The arcuate line is a relevant structure when reconstructing the abdominal wall after rectus abdominis musculocutaneous flap harvest. Its location is classically taught to be half the distance from the pubic symphysis to the umbilicus, but recent anatomic literature provides evidence to the contrary. Better understanding of the relationship between the arcuate line and surface anatomic landmarks could facilitate better preoperative planning when harvesting a rectus abdominis musculocutaneous flap. A total of 32 arcuate lines were dissected in 18 cadavers, and the location was correlated to various surface anatomic landmarks. The arcuate line was found to lie at 74.6% of the distance from the pubic symphysis to the umbilicus, and 32.7% of the distance from the pubic symphysis to the xiphoid. This location was 1.8 +/- 1.7 cm superior to the level of the anterior superior iliac spines (ASIS). This study provides further support for the finding in the anatomic literature that the arcuate line is substantially more superior than classically described. This knowledge may prove useful in preoperative planning of rectus abdominis musculocutaneous flap harvest.  相似文献   
25.
BACKGROUND: The authors characterized the unanticipated reoperations after prophylactic mastectomy, with or without implant reconstruction. METHODS: The surgical cohort was comprised of 1417 women with a family history of breast carcinoma. The women received a prophylactic mastectomy with (bilateral, n = 593; contralateral, n = 506) or without reconstruction (n = 318) at the Mayo Clinic (Rochester, MN) between 1960 and 1993. Reoperations and indications for reoperation were compiled from medical records and a patient survey. RESULTS: Three hundred eighteen women received a bilateral (n = 39) or contralateral (n = 279) prophylactic mastectomy without reconstruction. With a median follow-up of 15 years, 18 women (6%) required reoperation. Most of these reoperations occurred within the first year after prophylactic mastectomy. Five hundred ninety-three women had reconstruction with implants following bilateral prophylactic mastectomy. Approximately one-half of the women (52%) required at least 1 unanticipated reoperation during a median follow-up of 14 years. Approximately 39% of all reoperations occurred within 1 year of breast reconstruction and 69% within 5 years. Implant-related issues were the most common cause for reoperation. Some women with breast carcinoma elected to receive contralateral prophylactic mastectomy with therapeutic mastectomy for the affected breast. Five hundred six women received reconstruction with implants. During a median follow-up of 8.8 years, 189 women (37%) required unanticipated reoperation. The most common indication was implant-related issues. The time course of reoperations was similar to that for women in the bilateral group. CONCLUSIONS: Surgical reoperations were fairly common among women who received prophylactic mastectomy with implant reconstruction. Most of the reoperations were implant related. Reoperations were fairly uncommon after prophylactic mastectomy without reconstruction.  相似文献   
26.
In this paper, the dependencies between phenomenological coefficients for membrane and friction coefficients for solutes and membrane in the framework of generalised Spiegler-Kedem-Katchalsky model for non-ionic and homogeneous solutions were presented. The matrixes of transformation from phenomenological onto frictional coefficients and from frictional onto phenomenological coefficients were worked out. Besides, the influence of hydration number of solutes on friction and phenomenological coefficients was elaborated. Moreover, the friction coefficients and their dependencies on hydration number of glucose for aqueous glucose solution (binary solution) and glucose solution in aqueous ethanol solution (ternary solution), permeating through flat polymer membrane were presented.  相似文献   
27.
Colorectal adenomas can be morphologically classified as exophytic or flat. Polypoid cancers and cancers arising de novo (ie., without any adenomatous component) might be the results of genetic progression from exophytic and flat adenomas, respectively. In this study, we examined 94 morphologically distinct neoplastic specimens for mutations in K-RAS and analyzed 10 microsatellite loci tightly linked to the tumor suppressor genes APC, p53, DCC/SMAD4, hMSH2, and hMLH1. K-RAS mutations were significantly associated with exophytic adenomas [11 of 21 (52%)] compared to flat adenomas [2 of 13(15%), P < 0.03] and polypoid cancers [17 of 25 (68%)] compared to cancers arising de novo [7 of 25 (28%), P < 0.01]. Two polypoid cancer cases demonstrated three and four different K-RAS mutations, respectively, suggesting multiple areas of clonal expansion. Cancers arising de novo were significantly associated with loss of heterozygosity (LOH) at chromosome 3p compared to pol ypoid cancers [6 of 18(33%) versus 1 of 20(5%), P < 0.03], whereas the prevalence of LOH at chromosomes 2p, 5q, 17p, and 18q and microsatellite instability were not different between the groups. For all cancers, LOH at chromosomes 17p and 18q occurred in 47 and 51%, respectively. However, LOH at 17p and 18q occurred in 0 and 16% of benign lesions, respectively, suggesting their role in malignant transformation. There was no difference in LOH at chromosomes 17p and 18q between exophytic and flat lesions. These findings suggest that (a) mutant K-RAS is associated with the exophytic growth of colonic neoplasms, and that (b) some colorectal cancers arising de novo lose chromosome 3p during their evolution, which is not seen in polypoid cancers. Half of all cancers lose chromosomes 17p and 18q at or near the malignant transition of benign lesions as reported previously, irrespective of morphology. There may be more than one genetic avenue for colorectal cancer formation, and this correlates with the morphological characteristics.  相似文献   
28.
Objectives. To develop a model that will identify a contemporary cohort of patients at high risk of early prostate cancer recurrence (greater than 50% at 36 months) after radical retropubic prostatectomy for clinically localized disease. Data from this model will provide important information for patient selection and the design of prospective randomized trials of adjuvant therapies.Methods. Proportional hazards regression analysis was applied to two patient cohorts to develop and cross-validate a multifactorial predictive model to identify men with the highest risk of early prostate cancer recurrence. The model and validation cohorts contained 904 and 901 men, respectively, who underwent radical retropubic prostatectomy at Johns Hopkins Hospital. This model was then externally validated using a cohort of patients from the Mayo Clinic.Results. A model for weighted risk of recurrence was developed: RW′=lymph node involvement (0/1)×1.43+surgical margin status (0/1)×1.15+modified Gleason score (0 to 4)×0.71+seminal vesicle involvement (0/1)×0.51. Men with an RW′ greater than 2.84 (9%) demonstrated a 50% biochemical recurrence rate (prostrate-specific antigen level greater than 0.2 ng/mL) at 3 years and thus were placed in the high-risk group. Kaplan-Meier analyses of biochemical recurrence-free survival demonstrated rapid deviation of the curves based on the RW′. This model was cross-validated in the second group of patients and performed with similar results. Furthermore, similar trends were apparent when the model was externally validated on patients treated at the Mayo Clinic.Conclusions. We have developed a multivariate Cox proportional hazards model that successfully stratifies patients on the basis of their risk of early prostate cancer recurrence.  相似文献   
29.
BACKGROUND: The correlation of surgical margins and extraprostatic extension (EPE) with progression is uncertain with regard to prostate carcinoma patients treated by radical prostatectomy. The objective of this study was to define factors predictive of cancer progression; emphasis was placed on surgical margins and their relation to extraprostatic extension. METHODS: The study group consisted of 377 patients who were treated by radical retropubic prostatectomy and bilateral pelvic lymphadenectomy at the Mayo Clinic between 1986 and 1993. All specimens were totally embedded and whole-mounted. Patients ranged in age from 41 to 79 years (mean, 65 years). Those with seminal vesicle invasion or lymph node metastasis and those treated preoperatively with radiation or androgen deprivation were excluded. Final pathologic T classifications were pT2a (41 patients), pT2b (237), and pT3a (99). Progression was defined as biochemical failure (prostate specific antigen [PSA] >0.2 ng/mL), clinical or biopsy-proven local recurrence, or distant metastasis. The mean follow-up was 5.8 years (range, 0.2-11.4 years). Seventy-nine patients who received adjuvant treatment within 3 months after surgery were excluded from survival analysis. RESULTS: The overall margin positivity rate was 29%. Seventy-two patients (19%) had only positive surgical margins without evidence of EPE ("surgical incision"), 53 (14%) had only EPE, 37 (10%) had both, and 215 (57%) had neither. Positive margins were correlated with the finding of EPE (P = 0.003). Progression free survival rates at 5 and 10 years were 88% and 67%, respectively. In univariate analysis, preoperative PSA concentration, positive surgical margins, Gleason grade, cancer volume, and DNA ploidy were significant in predicting progression (P values, <0.001, <0.001, 0.01, 0.007, and <0.001, respectively). In multivariate analysis, margin status and DNA ploidy were independent predictors of progression (relative risk for margin status, 1.9; 95% confidence interval [CI], 1.1-3.4; P = 0.03; relative risk for DNA ploidy, 5.1; 95% CI, 2.4-10.9; P<0.001). Among patients with positive margins, 5-year progression free survival was 78% for those with negative EPE and 55% for those with positive EPE. CONCLUSIONS: Surgical margin status and DNA ploidy were independent predictors of progression after radical prostatectomy. To improve cancer control, adjuvant therapy may be considered for patients with positive surgical margins or nondiploid cancer.  相似文献   
30.
Dust-like opacities of the vitreous body are the main feature of all types of intermediary uveitis. In addition recurrent vitreous hemorrhages occasionally occur. They mark the vasoproliferative form of the inflammation and originate from different regions of the posterior segment of the eye; their distribution sometimes enables conclusions to be drawn concerning the site of the vasoproliferation.  相似文献   
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