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121.
The histologic diagnosis of adult renal epithelial neoplasms with prominent eosinophilic cytoplasm (renal oncocytoma, chromophobe renal-cell carcinoma (RCC), eosinophilic variant of clear-cell RCC, eosinophilic variant of papillary RCC, and collecting duct carcinoma), could be problematic in some cases because of overlapping morphologic features. Precise diagnosis is essential, however, because it often connotes a distinct biologic behavior. Proliferative activity has not been specifically investigated in this spectrum of renal tumors, so we studied the MIB-1 proliferation index in 20 renal oncocytomas, 12 chromophobe RCCs, 9 eosinophilic variants of papillary RCCs, and 13 eosinophilic variants of clear-cell RCCs. Our purpose was to identify the biologic potential of these renal tumors on the basis of MIB-1 tumor proliferation index and to ascertain whether that index had diagnostic value. Overall, nuclear grade correlated with MIB-1 tumor proliferation index (P=.03). The mean proliferation index progressively increased from renal oncocytomas (0.3) to chromophobe RCCs (0.8) to eosinophilic variants of papillary RCCs (2.2) to eosinophilic variants of clear-cell RCCs (4.1) (P=.002). None of the renal oncocytomas or chromophobe RCCs had an index greater than 2, whereas 8 of 13 eosinophilic variants of clear-cell RCCs had an index greater than 2; in 5 of these, it was more than 3. Thus, in the differential diagnosis between renal oncocytoma/chromophobe RCC and eosinophilic variant of RCC, an MIB-1 index of greater than 3 with appropriate morphologic correlation would strongly support the diagnosis of the latter. We also concluded that the progressive increase in MIB-1 tumor proliferation index across the spectrum of granular renal-cell neoplasms parallels the emerging data in the current literature concerning the biologic potential of adult renal epithelial tumors and justifies histologic categorization of adult renal epithelial neoplasms.  相似文献   
122.
N-Phthaloyl 3-amino-3-arylpropionic acid analogs of thalidomide that are potent inhibitors of tumor necrosis factor-alpha are reported. These compounds were found to be potent inhibitors of phosphodiesterase 4.  相似文献   
123.
This epidemiological study investigated the reasons why children in Northern Ireland who need orthodontic treatment do not receive treatment even when it is provided free by the state. A total of 1584 15- and 16-year-olds were examined in 23 high schools with the Index of Orthodontic Treatment Need. The characteristics of the adolescents who had received orthodontic treatment were compared with those who had a definite need for treatment and yet did not receive treatment or advice. One in 10 of the adolescents examined had an unmet need for orthodontic treatment. Logistic regression analysis was used to assess the influence of 11 variables including socioeconomic status, religion, and standard of dental health on the uptake of orthodontic care. This analysis revealed that the only significant predictors of whether an adolescent received orthodontic treatment was the dental attendance pattern of the adolescent, the adolescent's dental health, and the dental attendance pattern of the adolescent's mother. Those adolescents who had good dental health, who regularly attended a dentist, and whose mother regularly attended a dentist were more likely to receive orthodontic treatment.  相似文献   
124.
Life-threatening complications of central venipuncture are rare. We report an unusual case of a patient in whom a large right subclavian pseudoaneurysm developed, causing pressure necrosis of the membranous trachea and esophagus, after right internal jugular vein cannulation. The patient underwent oversewing of the proximal and distal ends of the subclavian artery and primary tracheal repair. An esophageal leak that presented on the sixth postoperative day was treated by primary suture repair with proximal and distal diversion.  相似文献   
125.
Two months after colic surgery, subcutaneous masses were found on the ventral and lateral portions of the thorax of a 3-year-old Hanoverian-cross filly. Six months later, the filly was admitted for evaluation of severe lameness. Arthrocentesis of the tarsocrural joint yielded clotted sanguineous material; however, unusual multinucleated giant cells were seen. Radiography of the right tarsus revealed soft tissue opacity and degenerative joint disease. The filly was euthanatized to prevent further suffering. At necropsy, multiple soft-tissue masses were located throughout the fascial planes of the tarsi and in the subcutis of the ventral and lateral portions of the thorax. Neoplasms consisted primarily of a large number of mature well-differentiated T lymphocytes. On the basis of these findings, the diagnosis was cutaneous lymphoma with unusual involvement of periarticular tissues. Severe degenerative joint disease in the right tarsus did not appear to be associated with the tumors.  相似文献   
126.
BACKGROUND: The reliable interpretation of the nasal provocation test in allergy diagnosis requires objective and measurable monitoring parameters for clinical practice. The clinical usefulness of the nasal provocation test has been limited by scanty knowledge of the specificity and sensitivity of the test and a lack of reference values. OBJECTIVE: To test and compare three objective monitoring parameters of a nasal provocation test in occupational allergic rhinitis. To evaluate the magnitude of the nasonasal effects in a unilateral allergen challenge. METHODS: The monitoring parameters of the nasal reaction were derived from the minimum cross-sectional area on acoustic rhinometry, the nasal resistance on active anterior rhinomanometry and the amount of nasal secretion measured at 15 min intervals for 60 min. Twenty-three bovine-allergic dairy and beef cattle farmers and 19 exposed, non-allergic control subjects were challenged first with a control solution and then with the cow allergen. RESULTS: All the three monitoring parameters showed high specificity and sensitivity in finding allergic and non-allergic subjects. The secretion parameter was found to be slightly superior to the acoustic rhinometry and rhinomanometry parameters. The side difference in the nasal response between the allergen-challenged and the contralateral diluent-challenged cavity was significant for all the parameters among the allergic subjects. The contralateral secretion amount was 1/3 of the ipsilateral secretion, indicating the magnitude of the contralateral nasonasal reflex. A nasonasal reflex was also noted in the nasal patency monitoring. The coefficient of variation was significantly lower for the acoustic rhinometry than for the rhinomanometry (P=0.0001). The optimal threshold values for a positive test were a secretion amount of 100 mg, a 15% decrease in the minimum cross-sectional area and a 50% increase in the resistance for the observation period of 30 min and correspondingly 210 mg, 30% and 100% for 60 min. CONCLUSION: The low-pressure aspiration of the nasal secretion from the anterior part of the nasal cavity was found to be a reliable and practical monitoring parameter to be used together with acoustic rhinometry or rhinomanometry in the nasal provocation test for clinical purposes. Although significant nasonasal effects took place in the unilateral allergen challenge, the response was more prominent in the allergen-challenged than in the contralateral diluent-challenged nasal cavity in most allergic subjects.  相似文献   
127.
In analyses of patient survival it is often desirable to compare observed survival curves with expected survival curves based on information obtained from the general population. However, current methods of calculating expected survival curves are difficult to interpret and are often poorly documented. We discuss an alternative formulation of the so-called direct method which we recommend for general use. By simulation, we show that the expected survival curve obtained from this method represents the expectation of a Kaplan-Meier curve for a set of random population controls. Thus, the term expected survival does not refer to the expectation of patient survival, but rather to the expected survival curve for a random set of controls. The alternative methods are discussed, and we illustrate the methods in an analysis of long time survival of a population-based sample of peptic ulcer patients.  相似文献   
128.
The substituted triphenylethylene antiestrogen clomiphene (CLO) prevents cancellous bone loss in ovariectomized (OVX'd) rats. However, CLO is a mixture of two stereoisomers, enclomiphene (ENC) and zuclomiphene (ZUC), which have distinctly different activities on reproductive tissues and tumor cells. The purpose of the present dose response study was to determine the effects of ENC and ZUC on nonreproductive estrogen target tissues. These studies were performed in 7-month-old female rats with moderate cancellous osteopenia that was established by ovariectomizing rats 1 month before initiating treatment. OVX resulted in increases in body weight, serum cholesterol, endocortical resorption, and indices of cancellous bone turnover, as well as decreases in uterine weight, uterine epithelial cell height, bone mineral density, bone strength, and cancellous bone area. Estrogen treatment for 3 months restored body weight, uterine histology, dynamic bone measurements, and osteoblast and osteoclast surfaces in OVX'd rats to the levels found in the age-matched sham-operated rats. In contrast, estrogen only partially restored cancellous bone volume and uterine weight, and it reduced serum cholesterol to subnormal values. CLO was a weak estrogen agonist on uterine measurements and a much more potent agonist on body weight, serum cholesterol, and dynamic bone measurements. CLO increased trabecular thickness in osteopenic rats and was the most effective treatment in improving cancellous bone volume and architecture. ZUC was a potent estrogen agonist on all tissues investigated and had dose-dependent effects. In contrast, ENC had dose-dependent effects on most measurements similar to CLO and decreased the uterotrophic effects of ZUC. It is concluded that ENC antagonizes the estrogenic effects of ZUC on the uterus but that the beneficial effects of CLO on nonreproductive tissues in OVX'd rats is conferred by both isomers. Furthermore, the combined actions of the two isomers on bone volume and architecture were more beneficial than either isomer given alone.  相似文献   
129.
Dehydration and hyperthermia may impair gastric emptying (GE) during exercise; the effect of these alterations on intestinal water flux (WF) is unknown. Thus the purpose of this study was to determine the effect of hypohydration ( approximately 2.7% body weight) on GE and WF of a water placebo (WP) during cycling exercise (85 min, 65% maximal oxygen uptake) in a cool environment (22 degrees C) and to also compare GE and WF of three carbohydrate-electrolyte solutions (CES) while the subjects were hypohydrated. GE and WF were determined simultaneously by a nasogastric tube placed in the gastric antrum and via a multilumen tube that spanned the duodenum and the first 25 cm of jejunum. Hypohydration was attained 12-16 h before experiments by low-intensity exercise in a hot (45 degrees C), humid (relative humidity 50%) environment. Seven healthy subjects (age 26.7 +/- 1.7 yr, maximal oxygen uptake 55.9 +/- 8.2 ml . kg-1 . min-1) ingested either WP or a 6% (330 mosmol), 8% (400 mosmol), or a 9% (590 mosmol) CES the morning following hypohydration. For comparison, subjects ingested WP after a euhydration protocol. Solutions ( approximately 2.0 liters total) were ingested as a large bolus (4.6 ml/kg body wt) 5 min before exercise and as small serial feedings (2.3 ml/kg body wt) every 10 min of exercise. Average GE rates were not different among conditions (P > 0.05). Mean (+/-SE) values for WF were also similar (P > 0.05) for the euhydration (15.3 +/- 1.7 ml . cm-1 . h-1) and hypohydration (18.3 +/- 2.6 ml . cm-1 . h-1) experiments. During exercise after hypohydration, water absorption was greater (P < 0.05) with ingestion of WP (18.3 +/- 2. 6) and the 6% CES (16.5 +/- 3.7), compared with the 8% CES (6.9 +/- 1.5) and the 9% CES (1.8 +/- 1.7). Mean values for final core temperature (38.6 +/- 0.1 degrees C), heart rate (152 +/- 1 beats/min), and change in plasma volume (-5.7 +/- 0.7%) were similar among experimental trials. We conclude that 1) hypohydration to approximately 3% body weight does not impair GE or fluid absorption during moderate exercise when ingesting WP, and 2) hyperosmolality (>400 mosmol) reduced WF in the proximal intestine.  相似文献   
130.
BACKGROUND: Few studies have compared the outcome of radical prostatectomy between African-American males (AAM) and white males, and the results of the few studies that have are conflicting. Therefore, the authors examined the impact of radical surgery on localized prostate carcinoma in both patient populations, and assessed whether stratification by pathologic extent of local disease would yield an equivalent outcome. METHODS: Prostate specific antigen (PSA) failure and carcinoma-associated death rates were assessed in 1319 patients (115 AAM and 1204 white males), 872 of whom had a pretreatment serum PSA level taken. The percent of prostate involved by tumor, tumor wet weight, and DNA ploidy status were available in 755, 522, and 638 patients, respectively. RESULTS: AAM were diagnosed at an earlier age than white males (62.8 years vs. 65.4 years; P = 0.0001). The distribution of pathologic extent of local disease was similar in both races, and AAM had a statistically higher rate of tumors with a Gleason sum of 7-10 at surgery than white males (64% vs. 46%). Race did not play a role in the outcome of patients with organ-confined or specimen-confined tumors. However, in patients with positive surgical margins, the median time to PSA failure and the median carcinoma-associated survival were less in AAM compared with white males. Tumor volume was significantly larger in AAM compared with white males. After multivariate adjustment for the pathologic extent of local disease, tumor grade at surgery, preoperative PSA, tumor volume, and age, African-American race was not a significant prognostic indicator for carcinoma-associated death and PSA failure (P = 0.17 and 0.14, respectively). CONCLUSIONS: The outcome of radical prostatectomy was similar in both racial groups, although AAM with positive surgical margins tended to fail earlier than white males, suggesting greater biologic aggressiveness of residual disease. Because local extent of disease impacts on PSA failure and survival, and because the disease appears to present earlier in AAM, the AAM population may benefit from early detection programs.  相似文献   
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