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排序方式: 共有823条查询结果,搜索用时 15 毫秒
1.
Differential distribution of pepsinogen II between the zones of the human prostate and the seminal vesicle 总被引:2,自引:0,他引:2
J H Reese J E McNeal E A Redwine I M Samloff T A Stamey 《The Journal of urology》1986,136(5):1148-1152
Pepsinogen II (PG II) is a gastric proenzyme which has previously been found in both human seminal fluid and the prostate gland. However, no regional distribution of PG II has been noted within the prostate nor has it been found in the seminal vesicle. Bouins-fixed sections of central zone, peripheral zone and seminal vesicle, taken from 10 prostates removed at radical prostatectomy or cystectomy, were exposed to antibody against PG II and stained using the A-B-C immunoperoxidase technique. Formalin-fixed tissue from autopsy prostates of four men in the third decade, and six cases with BPH nodules, were also examined for PG II activity. In nine of 10 seminal vesicles, and seven of 10 central zone samples, more than 50 per cent of the cells stained positive for PG II. By contrast, in nine of 10 peripheral zone samples staining was present in five per cent or less of the epithelial cells. Similarly, PG II activity in the four autopsy prostates occurred almost entirely within the central zone and ended abruptly at the boundary between the peripheral and central zones. BPH nodules contained no PG II activity. These findings provide the first evidence that the central and peripheral zones may serve different biological functions. Embryologically it is currently thought that the prostate is of endodermal origin and the seminal vesicle of mesodermal origin. The presence of large amounts of PG II in both the seminal vesicle and central zone lends support to the hypothesis of a common mesodermal origin for these two structures. 相似文献
2.
Pathogenesis and biological significance of seminal vesicle invasion in prostatic adenocarcinoma 总被引:2,自引:0,他引:2
A A Villers J E McNeal E A Redwine F S Freiha T A Stamey 《The Journal of urology》1990,143(6):1183-1187
Seminal vesicle invasion and the percentage involvement by cancer of each seminal vesicle were related to cancer volume, quantitative histological grade and presence or absence of lymph node metastases in 243 radical prostatectomy specimens. There were 47 prostates with seminal vesicle invasion. Frequency and extent of seminal vesicle invasion were strongly correlated with cancer volume, with minimal invasion noted in only 6% of the cases less than 4 cc. The relationship of seminal vesicle invasion to lymph node metastasis was statistically significant but cancer volume and histological grade were much stronger predictors of lymph node metastasis. The route of invasion from the prostate in 46 cases involved direct tumor spread into the midbase region near the ejaculatory ducts. Seminal vesicle invasion often may not be identified if the tissue nearest the ejaculatory ducts at the prostate base is not sampled. 相似文献
3.
Pathology of benign prostatic hyperplasia. Insight into etiology. 总被引:17,自引:0,他引:17
J McNeal 《The Urologic clinics of North America》1990,17(3):477-486
Morphometric studies of prostates with benign hyperplasia (BPH) have revealed features that may help clarify the disease's natural history and biologic behavior. Hyperplasia arises within a small anatomic region having precise boundaries and containing an unusual juxtaposition of glandular and stromal elements. Diffuse non-nodular enlargement of the transition zone is the commonest morphologic feature of BPH, but nodules show a greater potential for growth and comprise most of the tissue in large (more than 50-gm) resection specimens. Most nodules are predominantly glandular, with features that suggest a pathogenetic role of induction of embryonic-type stroma. 相似文献
4.
Distribution of lactoferrin in the normal and inflamed human prostate: an immunohistochemical study. 总被引:2,自引:0,他引:2
A polyclonal rabbit antibody to lactoferrin was used to localize the distribution of lactoferrin within the different zones of the normal human prostate as well as within the inflamed human prostate. Cases of normal central zone, peripheral zone, periurethral glandular tissue, as well as cases in which foci of moderate to severe inflammation, along with varying degrees of inflammation-related atrophy, were studied. In cases with inflammation, the staining pattern of lactoferrin was compared to the staining pattern of prostate-specific antigen. Within the central zone, lactoferrin staining occurred in numerous individual cells peppered throughout the epithelium as well as within multiple intraepithelial lumens (lacunae). These lacunae were often numerous enough to give the central zone epithelium a fenestrated appearance; they were not seen in any of the other regions of the prostate. With the exception of an occasional individual cell or isolated positive gland, normal peripheral zone exhibited very little lactoferrin activity. Staining within the transition zone was similar to that seen in the peripheral zone. Staining within the urethral lining of the epithelium in the periurethral glands showed a distinct pattern of frequent intense staining involving the entire gland; frequent individual positive cells were also often seen. Three patterns of staining were identified in prostatic inflammation. Mild periglandular chronic inflammation produced foci of epithelial lactoferrin positivity that coincided precisely with the areas of inflammation. Severe acute inflammation produced strong staining within luminal secretions while cytoplasmic staining was limited to the luminal surface of the epithelium. Post-inflammatory atrophy showed intense diffuse lactoferrin staining in the scant cytoplasm of the atrophic epithelium. In 12 of the 17 cases of inflammation that were studied, areas of post-inflammatory atrophy or severe inflammation commonly showed absence of prostate specific antigen staining and epithelium that was strongly lactoferrin-positive. Within the normal human prostate, lactoferrin appears to be produced primarily within the epithelium of the central zone, periurethral glands, and lining epithelium of the prostatic urethra. Lactoferrin-filled central zone lacunae appear to be structures unique to the central zone. The distribution of lactoferrin in the periurethral glands and urethral lining epithelium, along with the intense production of lactoferrin in the presence of inflammation, and the preservation of lactoferrin production in severe inflammation or atrophy suggest that lactoferrin may be a key component of the inflammatory response within the human prostate. 相似文献
5.
Positive surgical margins at radical prostatectomy: importance of the apical dissection 总被引:5,自引:0,他引:5
T A Stamey A A Villers J E McNeal P C Link F S Freiha 《The Journal of urology》1990,143(6):1166-72; discussion 1172-3
Positive margins were analyzed in 189 clinical stage B radical retropubic prostatectomies. Margins were identified by serially blocking the entire specimens in planes selected for optimum demonstration of capsule surface. Positive margins were divided into 2 categories: 1) those associated with capsular penetration of cancer and 2) those caused by inadvertent surgical incisions through the capsule into intracapsular cancer. Data were analyzed separately at each of 6 anatomical sites. Frequency of positive margins was related to the volume of cancer. Cancer of greater than 12 cc constituted a distinctive category in which seminal vesicle invasion, lymph node metastases and multiple positive margins were found in the majority of cases, signifying minimal possibility of cure. However, 31 positive margins occurred among 136 patients (23%) who were potentially curable by the criteria of normal seminal vesicles and absence of pelvic lymph node metastases; 17, of these 31 surgically positive margins (55%) occurred at the apex. Positive capsular penetration margins at the apex were volume-related, while negative margins were not. Site specific recommendations for avoiding positive and negative capsular penetration margins are suggested. The prostate apex, rectal and lateral surfaces, bladder neck and superior pedicles accounted for 48, 24, 16 and 10% of all positive margins, respectively. Dissection of the apical prostate and Denonvilliers' fascia require modifications of current surgical techniques if positive margins are to be avoided. Serum levels of prostate specific antigen may require as long as 5 years to become detectable when only 1 positive margin is the only evidence of nonorgan-confined disease. 相似文献
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9.
Drug education practice: results of an observational study. 总被引:3,自引:0,他引:3
Understanding normative practice in drug education is a key to identifying means of improving preventive intervention outcomes. In this paper, we report findings of an observational study in which drug education in multiple periods of 146 middle school classes was categorized minute-by-minute according to the type of instruction provided to students. Results indicate that nearly half of all drug education focused on providing students with knowledge. Alternative methods, particularly those that have shown programmatic effectiveness, and those that address risk and protective factors known to be highly predictive of drug use onset, were relatively ignored. Further, teachers showed relatively low consistency in understanding concepts other than knowledge based on comparisons of their ratings of intended instructions with those of trained observers. Nonetheless, there is evidence that some teachers systematically attempted to address drug prevention from either a social influence or an affective education perspective. These findings suggest that if improvements in the effectiveness of drug education are to be seen in the future, a relatively radical transformation of approaches to teaching will be needed. 相似文献
10.
John E. McNeal 《The Prostate》1981,2(1):35-49
Earlier morphologic studies of the prostate, though often extensive, have never systematically delineated its complete structure. Recent comprehensive analysis of 500 prostates has more precisely defined its anatomic composition, identifying previously undetected features and unsuspected complexities. Using a three-dimensional model, these structures and relationships are demonstrated. Four basic anatomic regions are described. The relationship of each to the urethra provides a central anatomic reference point.
- 1 The peripheral zone constitutes over 70% of the glandular prostate. It forms a disc of tissue whose ducts radiate laterally from the urethra lateral and distal to the verumontanum. Almost all carcinomas arise here.
- 2 The central zone constitutes 25% of the glandular prostate. Its ducts arise close to the ejaculatory duct orifices and follow these ducts proximally, branching laterally near the prostate base. Its lateral border fuses with the proximal peripheral zone border, completing in continuity with the peripheral zone, a full disc of secretory tissue oriented in a coronal plane. Marked histologic differences between central and peripheral zones suggest important biologic differences.
- 3 Preprostatic region. The urethral segment proximal to the verumontanum is kinked anteriorly at a 35-degree angle to the distal segment. No major ducts arise in the proximal segment, but the lateral rows of peripheral zone orifices continue. Duct development is aborted here, producing only a small transition zone and several tinier periurethral ducts. The development of these small ducts is possibly determined and limited by their intimate relationship to a periurethral smooth muscle sphincter that exists only proximal to the verumontanum. These small ducts in a restricted area are the exclusive site of nodular hyperplasia (BPH) origin.
- 4 The anterior fibromuscular stroma forms the entire anterior surface of the prostate as a thick, nonglandular apron, shielding from view the anterior surface of the three glandular regions. Its inseparable fusion to the glandular prostate has probably delayed recognition of the anatomic features described here.