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Anisotropic magnetoresistance (AMR) effect on a Weyl semimetal Co2MnAl Heusler alloy was experimentally and theoretically investigated by changing the Co content, the direction of electric current against the crystal axis, and the measurement temperature. The experimentally fabricated Co2MnAl thin films epitaxially grown on a MgO single-crystal substrate showed the positive AMR ratios independent of the Co content, the direction of electric current, and the measurement temperature. The AMR ratios for the direction of electric current along Co2MnAl[100] were larger than those along Co2MnAl[110]. The maximum AMR ratios for Co2MnAl[100] were 0.576% at 5 K and 0.349% at 300 K for a Co content of 47 at. %, which is close to the stoichiometric composition. Furthermore, the theoretical calculations of AMR ratios based on the s-d scattering process of the electrons at the Fermi energy, including the information on the density of states (DOS) obtained from first-principles calculations, exhibited trends similar to the experimental results. Compared with the AMR results of Co2MnGa[110], we found that the magnitude relation between the partial DOS of the ε and γ orbitals of the d state of Co atoms determined the sign of the AMR ratios. These results suggest that the AMR effect of Weyl semimetal Co2MnAl can be elucidated by the s-d scattering process of the electrons.

To realize high data-transfer rate in random access, several kinds of DRAMs with on-chip cache memory have been proposed. These DRAMs rely on locality of access to achieve the highest speed. However, in some graphic applications where sufficient locality of access is not expected, such DRAMs will not greatly accelerate system performance. Embedded memories have benefits for such applications due to their wide data bus and band width. The 8 Mb embedded DRAM presented in this paper provides 1.6 GB/s data transfer rate and realizes 10 ns cycle random access without page fault delay.

DNA-dependent protein kinase (DNA-PK), consisting of a catalytic subunit (DNA-PKcs) and the Ku70 and Ku86 proteins, participates in the repair of DNA double-strand breaks (DSBs). We assessed its expression immunohistochemically in normal human colon tissue, colon adenomas, colon carcinomas, and normal tissue distant from carcinomas. Normal colonocytes expressed all DNA-PK proteins. Compared with the expression in normal tissue [176.62 +/- 18.56 (the intensity of expression x the percentage of cells expressing this protein), mean + SE], the expression of Ku70 was significantly reduced in adenomas (36.62 +/- 11.09; P0.001) and carcinomas (85.68 +/- 15.76; P0.01), as was the expression of Ku86 [(113.10 +/- 10.22 versus 41.66 +/- 14.71 in adenomas (P0.01) or versus 85.68 +/- 15.76 in carcinomas (P0.05)]. The expression of DNA-PKcs was not significantly changed. The marked underexpression of Ku70 and Ku86 starting at the adenoma stage may be crucial to the development of colon cancer.

We evaluated the systematic biopsies performed on 83 patients suspected of having prostate cancer. In the systematic biopsy, 6 cores were from the peripheral zone and 2 cores from the transition zone. Cancer was detected in 25 patients (30.1%). The percentage of patients who had abnormal digital rectal examination and transrectal echo findings, average PSA and PSA density, and the number of examinations which suggested cancer were higher in the cancer group than in the non-cancer group, although the mean prostate volume was smaller. Cancer was more frequently detected in the peripheral zone than in the transition zone. Cancer was detected only in the transition zone in only 1 of the 25 cancer patients. We conclude that biopsy of the transition zone to all the patients is not always needed in systematic biopsy.

The significance of prostate specific antigen (PSA) measured by DELFIA PSA kit in the 1,177 serum samples examined by mass screening for prostate cancer was evaluated. All subjects were examined by questionnaire, digital rectal examination (DRE) and prostatic acid phosphatase (PAP) and the subjects in whom prostate cancer was suspected from abnormal DRE and/or elevated PAP were recommended to receive the secondary screening for the presence of prostate cancer. All serum specimens used for this study were kept in our serum bank. The cut-off value was investigated between non-cancer subjects (diagnosed as normal, voiding disturbance or BPH) and prostate cancer patients. When the cut-off value was 2.89 ng/ml, the sensitivity, specificity and accuracy as prostate marker was 80.6%, 90.0% and 89.4%, respectively. Therefore, the cut-off value was determined as 3.0 ng/ml. The significance of PSA was retrospectively evaluated compared to PAP in the subjects examined by our mass screening. Twenty eight of the 39 palpable prostate cancers which could not be detected from the PAP level were detected from the PSA level, namely the sensitivity of the detection using the PSA level is more excellent than that using PAP. However, the false negative rate obtained using PSA was high (30.3%) in the patients with stage B disease. The relationship among serum PSA concentration, prostate size estimated by DRE and age was investigated. PSA was increased with age and prostate size. This estimation should be confirmed by using an ultrasonography because the prostate size obtained by DRE is inaccurate as compared with that obtained by ultrasonography.

Partial intestinal obstruction has been successfully managed by the use of long intestinal tubes. For proper decompression, the long tube must pass beyond the pylorus; however, failure of the tube to progress by gravity alone has been reported to be as high as 46 per cent. A simple method of endoscopic placement of the long tube into the duodenum is described. If one is familiar with performing upper endoscopy, this technique can be learned easily.

We have suggested a new method to evaluate brittleness KIC by use of a standerd hardness tester. We found the KIC value is controlled by the process. This method is useful to evaluate brittleness of small high Tc superconductor specimens.

Management of the malignant colonic polyp remains a subject for debate even after almost two decades of experience. Some researchers believe all patients should have a colonic resection; others argue that only certain cases call for laparotomy, while still others hold for a selective approach but with varying criteria. Therefore, a survey has been made of current practice and opinion from the time colonoscopic polypectomy was introduced in 1969 to the present. The authors have reviewed a sizable segment of their experience, dividing cases of malignant polyps into two broad categories: those in which complete polypectomy was followed by bowel resection; and those undergoing polypectomy alone. The determinants leading to one course or the other were analyzed, as were the results.

Preoperative plasma CEA levels were measured in 93 selected patients with histologically defined colorectal adenomata removed at fibroptic colonoscopy in order to determine whether CEA levels are elevated in patients with colonic polyps, or vary with different histologic patterns. None of the patients had inflammatory bowel disease, previous history of carcinoma, or evidence of liver disease. Fifteen percent of the patients had elevated CEA levels (greater than or equal to 2.5 ng/ml; Hansen method), and two-thirds of these were between 2.5 and 4.0 ng/ml. Increased association of elevated CEA levels was noted with old age, villous adenomas (2- to 4-fold), and increased tumor size (greater than 2.3-cm diameter; 2-fold), but not with foci of dysplasia or carcinoma in situ as such. One-half (7/14) of the patients with elevated CEA levels showed the following: two patients had villous tumors with carcinoma in situ, one had a villous adenoma, two had mixed villous and tubular adenomas (with a high proportion of villous pattern), and two were subsequently shown to have carcinoma elsewhere in the colon. It is uncertain that the polyps were the source of the elevated circulating CEA levels; other factors including smoking and patient selection need to be considered. This preliminary study suggests that patients with colorectal adenomata and elevated circulating CEA may be at higher risk for the development of carcinoma. Further follow-up studies of the malignant potential of the polyp-bearing colon are essential.

The flexible colonoscope has notable advantages over rigid instruments and can be offered as an alternative and (probably) preferable method for non-surgical reduction of colonic volvulus. When operative intervention is called for because of repeated bouts of sigmoid volvulus, colonoscopy offers a means of preoperative deflation of the twisted loop, allowing time to prepare the bowel and correct systemic disturbances such as electrolyte imbalance. The first successful management of a case of recurrent sigmoid volvulus using fiberoptic flexible colonoscope is presented. It is suggested that the fiberoptic colonoscope may have similar application for instances of volvulus occurring more proximal than in the sigmoid colon. Sigmoid volvulus in children even though rare might also be amenable to correction by colonoscopy.

The problem of the malignant potential of neoplastic colonic polyps is being, in large measure, resolved by newly derived techniques. Now most polyps may be removed endoscopically using the fiberoptic colonoscope. The largest world experience is at the Beth Israel Medical Center in New York, where over 2000 polyps have been endoscopically removed without a single death and with but one complication requiring operative intervention. Laparotomy is now reserved for polyps not suitable for endoscopic resection or where a question of residual cancer exists. Experience with endoscopic resection has called for: 1) re-assessment of colonic polyps in terms of their malignant potential; and 2) clarification of the indications for laparotomy and bowel resection subsequent to or instead of endoscopic removal. Among all polypoid lesions 0.5 cm or greater in size in the Beth Israel series, a variety of pathologic types was encountered. If only the neoplastic polyps were considered, the incidence of "malignant change" was 10.5% for 855 polyps analyzed. There is, however, a need to clarify terminology and to differentiate between carcinoma in situ and invasive cancer whenever possible. Superficial cancers (carcinomas in situ) do not recur or metastasize and require no treatment other than polyp removal. When "invasive" cancer is present (4.5% of neoplastic polyps) or the lesion is a "polypoid carcinoma" each case must be individually evaluted. Criteria for diagnosis, gross morphological features suggesting cancerous change, and current management of "malignant" polyps are discussed. Colonoscopy is an important component of the followup program whether malignant polyps are resected endoscopically or by the transabdominal route.

Gastrointestinal hemorrhage of obscure origin remains a difficult clinical problem, but newer methods of study, particularly endoscopy and angiography, have made inroads into this morass of diagnostic dilemmas. Vascular malformations represent entities that are relatively infrequent of occurrence and also difficult of detection. These characteristics render them particularly refractory to recognition. Once diagnosed, however, they are quite readily treated surgically, without resort to "blind" resections or multiple bowel entries. This report deals with three instances of obscure but important persistent blood loss into the gastrointestinal tract. In each instance, identification by customary diagnostic methods was unsuccessful, but was finally made through endoscopy and promptly cured through surgery. The bleeding in all 3 cases proved pathologically to have been caused by vascular malformations, which we have subsumed under the term "angiodysplasia."

The aim of this study was to elucidate whether cholecystokinin (CCK) had a role in the occurrence and/or in the development of experimental acute pancreatitis in rats, and furthermore to find the possibility for the treatment of acute pancreatitis with a CCK antagonist, proglumide. The administration of CCK-8 significantly increased serum levels of amylase, lipase and pancreatic wet weight. The administration of proglumide significantly reduced the blood levels of trypsin, pancreatic wet weight, water content and improved survival rate. These findings were supported by microscopic examination. The results of this study demonstrate that CCK has an important role in the development of acute pancreatitis and that proglumide might have prophylactic and therapeutic effects in acute pancreatitis.

A 33-year old female with a 10-year history of ulcerative colitis developed a large polypoid filling defect in the distal transverse colon, suggestive of carcinoma of the colon. Biopsy indicated an inflammatory polyp but subtotal colectomy was performed because of the long history and the radiographic appearance. Pathologic examination revealed an unusual aggregation of filiform polyps entrapping a semisolid fecal mass. The development of this unique lesion is elaborated.