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51.
Ohne ZusammenfassungHierzu Taf. I.Herr Dr. Tsutsui, der wesentlich an dem bakteriologischen Theil dieser Arbeit betheiligt ist, wurde durch seine plötzliche Abreise nach Japan von der weiteren Betheiligung abgehalten.  相似文献   
52.
Abstract: Ultrasonography (US) is one tool for preoperative diagnosis of lymph node metastases in breast cancer. However, US cannot detect true sentinel lymph nodes (SLNs). We identified SLNs in 60 clinically node‐negative breast cancer patients using a real‐time virtual sonography (RVS) system to display in real time a virtual multi‐planar reconstruction obtained from computed tomography (CT) volume data corresponding to the same cross‐sectional image from US. CT volume data were obtained from our original three‐dimensional CT lymphography (3DCT‐LG), which accurately detects SLNs in breast cancer. SLN metastases were assessed by shape and visibility of the hilum. All patients underwent SLN biopsy and SLN metastases were examined pathologically. In all 60 patients, we were able to detect the same SLNs visualized by 3DCT‐LG. Suspicious SLN metastases were identified in seven of the 60 patients, and four of seven patients were pathologically positive. Positive predictive value was 57%. The remaining 53 patients displayed non‐suspect SLNs in which absence of metastasis from the SLN was confirmed histologically. Overall accuracy was 95%. This is a first attempt at preoperatively identifying SLNs using US guided by the RVS system in breast cancer patients. Although evaluation of SLN metastases was unsatisfactory, this method may be useful for preoperative fine‐needle aspiration cytology for diagnosis of SLN metastases.  相似文献   
53.
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland.  相似文献   
54.
A 69-year-old woman underwent percutaneous coronary intervention for a severe stenotic lesion in the bifurcation of the mid-left anterior descending artery and first diagonal branch. A single stent was implanted into the left anterior descending artery. After the stent strut was dilated by balloon inflation in the diagonal branch, dissection occurred at the ostium of the diagonal branch and resulted in side branch occlusion due to hematoma. Bailout stenting was performed in the diagonal branch, but thrombus projection occurred in the left anterior descending artery. Aspiration, balloon inflation and thrombolytic therapy were performed, but distal embolism developed. This case illustrates that thrombus projection caused by stenting in a side branch may occur as a rare complication in percutaneous coronary intervention.  相似文献   
55.
BACKGROUND: The use of methylene blue chromoendoscopy in the diagnosis of specialized intestinal metaplasia in short-segment Barrett's esophagus is controversial. This study evaluated the use of magnifying endoscopy with methylene blue for this purpose. METHODS: A total of 30 patients (21 men, 9 women; median age 61 years, range 32-79 years) with short lengths of columnar-lined esophagus were enrolled in a prospective trial of magnifying endoscopy with methylene blue in which the appearance after methylene blue staining was used to target biopsy specimens. Patients were screened for Helicobacter pylori infection, and only those without infection were enrolled (because many Japanese patients have pan-gastritis caused by H pylori infection, and intestinal metaplasia distal to the squamocolumnar junction may be secondary to H pylori-induced gastritis). All biopsy specimens were stained with H and E; MUC2 immunostaining was used to identify specialized intestinal metaplasia. RESULTS: Thirty patients with short-segment columnar-lined esophagus underwent magnifying endoscopy with methylene blue. Ninety-three biopsy specimens were obtained, 33 from methylene blue-stained areas and 60 from unstained areas, each about 7 mm from the marginal edge of stained areas. Specialized intestinal metaplasia was confirmed in biopsy specimens from 28 of the 33 stained areas (sensitivity 84.8%); in biopsy specimens from 55 of the 60 unstained areas, specialized intestinal metaplasia was not found (specificity 91.7%). In magnified views of methylene blue-positive areas, a tubular, cavernous, or elliptical pattern was seen. Sixteen of 21 men (76.2%) and 3 of 9 women had specialized intestinal metaplasia, and short-segment Barrett's esophagus was diagnosed in these patients. Even in patients with less than 1 cm of columnar-lined esophagus, 8 of 10 stained areas contained specialized intestinal metaplasia (sensitivity 80%) and 23 of 24 unstained areas did not (specificity 95.8%). Six of 12 patients (50%) with less than 1 cm of columnar-lined esophagus had specialized intestinal metaplasia. In total, 19 of 30 patients had specialized intestinal metaplasia. CONCLUSIONS: Magnifying endoscopy with methylene blue selectively detects specialized intestinal metaplasia within short-segment columnar-lined esophagus.  相似文献   
56.
To examine the role of thyroid hormones in the seasonal breeding cycle in Japanese monkeys (Macaca fuscata fuscata), sexually mature females were thyroidectomized (n=6) in early December, during the midbreeding season, or they received sham operations (n=4). They were housed indoors individually, and blood samples were collected two to three times a week to monitor gonadotropin and gonadal steroid hormone secretions. Control monkeys exhibited ovulatory cycles during the breeding season. The mean dates of onset and end of the ovulatory cycles were October 22±13 d and February 25±14 d, respectively. These dates coincided well with those of our colonies under captivity. By contrast, three of the six thyroidectomized monkeys terminated ovulatory cycles immediately after operations; the remaining three monkeys ovulated only once or twice after thyroid removal. The mean dates of onset and end of the ovulatory cycles of thyroidectomized monkeys were October 18±4 d and December 31±4 d, respectively. This was a significantly earlier termination of the ovulatory cycles than in controls. Mean concentrations of plasma thyroxine of control monkeys were maintained throughout the experimental period, whereas plasma thyroxine concentrations of thyroidectomized monkeys decreased abruptly to undetectable levels. Thyroidectomized monkeys exhibited significantly higher levels of plasma prolactin (PRL) than controls. Moreover, even in control monkeys, plasma PRL increased during the transition out of the breeding season. These results suggest that thyroid hormones play an important role in the regulation of ovulatory cycles in Japanese monkeys, directory or indirectly, possibly by mediating the changes of PRL secretion.  相似文献   
57.
We report on a case of metastatic adenocarcinoma of liver that was removed and examined histochemically after microwave coagulation therapy (MCT). The patient was a 65-year-old woman who had a metastatic tumor in the liver (S3) after high anterior resection due to a rectal adenocarcinoma and received MCT against the tumor. One month after MCT, multiple metastatic tumors were detected by abdominal computed tomography (CT) scan. As it was difficult to control them by MCT alone, we performed lateral segmentectomy. To assess the effects of microwave ablation on cellular viability of metastatic tumor, we used enzyme histochemistry for acid phosphatase (AcP), which is positive in macrophages infiltrating in the tumor. In a part of the ablated area of resected liver, there was remaining neoplastic tissue of which the morphology was maintained in H&E staining. This was found to be microwave-fixed non-viable tissue because no enzyme activity of AcP was detected in the infiltrating macrophages. This case report suggests that enzyme histochemistry was useful to assess the effect of MCT, enabling us to distinguish fixed cells from viable cells.  相似文献   
58.
In a pilot study of 27 patients, those who presented with chest pain underwent 2 dobutamine stress echocardiographic studies, 1 with high mechanical index harmonic imaging to analyze wall motion without contrast and 1 with real-time low mechanical index perfusion imaging with intravenous Optison to assess myocardial perfusion and wall motion. All patients then underwent quantitative coronary angiography. Two independent reviewers demonstrated an improvement in sensitivity when analyzing myocardial perfusion. In the 21 patients who had significant coronary stenoses, 14 had abnormal myocardial perfusion detected at peak stress and 7 had abnormal wall motion detected by standard dobutamine stress echocardiography. There was decreased specificity with perfusion imaging by 1 reviewer. The addition of real-time perfusion imaging after intravenous contrast during dobutamine stress echocardiography has the potential to improve detection of coronary artery disease.  相似文献   
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