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To develop a model system containing regularly spaced misfit dislocations for studies of the radiation resistance of nanoscale defects, epitaxial thin films of Cr, Mo, and Cr(x)Mo(1-x) alloys were deposited on MgO(001) by molecular beam epitaxy. Film compositions were chosen to vary the lattice mismatch with MgO. The film structure was investigated by x-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and scanning transmission electron microscopy (STEM). Epitaxial films with reasonably high crystalline quality and abrupt interfaces were achieved at a relatively low deposition temperature, as confirmed by STEM. However, it was found by XRD and RBS in the channeling geometry that increasing the Mo content of the CrMo alloy films degraded the crystalline quality, despite the improved lattice match with MgO. XRD rocking curve data indicated that regions of different crystalline order may be present within the films with higher Mo content. This is tentatively ascribed to spinodal decomposition into Cr-rich and Mo-rich regions, as predicted by the Cr(x)Mo(1-x) phase diagram.

Fifty-two patients with ulcerative colitis and colorectal cancer undergoing colectomy at the Mount Sinai Hospital between 1973 and 1988 were studied retrospectively to determine the correlation of age, sex, duration of colitis, tumor location, number of cancers, tumor differentiation, colloid content, presence of signet ring cells, Dukes' classification, and DNA ploidy with survival. The mean age was 45 years, with a mean duration of colitis of 21 years. Five patients (10%) had Dukes' A lesions, 17 (33%) had Dukes' B lesions, 17 (33%) had Dukes' C lesions, and 13 (25%) had distant metastases. Thirty patients (58%) had well- or moderately differentiated tumors, whereas tumors were poorly differentiated in 22 (42%). Twenty-eight patients (54%) had colloid tumors, and, in 14 (27%), signet ring cells were present. Thirty-one patients (60%) had nondiploid tumors. Actuarial analysis revealed that the 5-year survival rate was significantly worse for patients with nondiploid tumors (76% versus 32%). When stratified by stage, only patients with Dukes' C lesions showed a significant difference in survival for diploid versus nondiploid tumors. Multivariate analysis showed that the Dukes' classification was the best prognostic indicator, followed by tumor differentiation and DNA ploidy. Tumor location, colloid content, number of cancers, duration of disease, age, and sex did not correlate with the prognosis.

Sixteen patients with polyposis coli and cancer were studied retrospectively to determine the incidence of DNA ploidy abnormalities in the tumors and synchronous polyps. Six patients (37 percent) had nondiploid tumors. Nondiploid tumors were more likely to be advanced and had a significantly worse prognosis (17 percent vs. 76 percent 5-year survival; P less than 0.01). Only 4 of 20 polyps studied were nondiploid. There was no association between tumor and polyp ploidy. All nondiploid polyps were found in patients with synchronous diploid cancers. Patients with nondiploid polyps were more likely to be older and have more advanced tumors than those with diploid polyps. DNA ploidy abnormalities seem to occur with the same frequency in polyposis coli as in the nonpolyposis population, and tumor ploidy correlates with prognosis.

A contemporary dilemma in nursing is the order to care in a society that refuses to value caring. The authors analyze the historical creation of this dilemma and its consequences for nursing. In addition, they explore the meaning of the concept of caring from a nursing perspective, along with the impact of technology on patients, providers, and caring. Finally, a framework and strategies for the promotion of caring within the discipline of nursing are presented.

Several studies have shown that the presence of DNA content abnormalities, measured by flow cytometry, may correlate with a poor prognosis in a variety of cancers. The predictive value of DNA content in patients with small rectal cancers has not been well determined. Thirty-nine patients with primary rectal adenocarcinoma smaller than 3 cm were studied in a comparison of DNA content with established prognostic variables. The following covariates were evaluated for their prognostic value: sex, age, tumor size, location, distal margin, Dukes' classification, tumor differentiation, and DNA content. DNA content was assessed by flow cytometric analysis, and each tumor was categorized as diploid or nondiploid. Of the parameters studied, Dukes' classification and tumor DNA content were found to be independent prognostic indicators. Determination of DNA content seems to provide additional useful prognostic information in patients with small rectal tumors.

A retrospective review of 24 patients with gallstone ileus from our institutions during the period from 1947 through 1981 has been presented. The study was undertaken in an attempt to refine the diagnosis and treatment of this rare entity. The patients ranged in age from 58 to 84 years, and 19 patients were women. The correct preoperative diagnosis was made in 74 percent of the patients using various combinations of clinical history, plain film roentgenograms, and barium contrast upper gastrointestinal series. After an average preoperative hospital stay of 4.5 days, 23 patients required operation. Wound infection developed in nine patients and resulted in wound dehiscence in two. There were four deaths in the patients over 73 years of age (p less than 0.01). Age was the only factor found to correlate with mortality.

We report a new technique for mucosal proctectomy that does not require manual separation of the mucosa and submucosa from the underlying muscularis. Mucosal proctectomy using ultrasonic fragmentation of the rectal mucosa was performed in four patients. Three had severe ulcerative colitis, and one patient had radiation proctitis with a rectal stricture. In all cases an endorectal pullthrough with anastomosis to the area of the dentate line was performed. Healing after ultrasonic mucosal proctectomy occurred without infection or retraction. Ultrasonic fragmentation offers an alternative to the standard technique of mucosal proctectomy. This new method is useful in those patients in whom separation of the rectal mucosal layer is difficult to perform.

A technique for performing mucosal proctectomy in patients with ulcerative colitis using ultrasonic fragmentation is described. Twenty-eight patients undergoing colectomy and ileoanal anastomosis were studied. Removal of the mucosal layer of the distal rectum was performed using a titanium probe vibrating at 23 kHZ with an amplitude of 300 microns. This method produces complete mucosal destruction and the resulting debris and irrigating fluid is removed through the hollow central portion of the probe. Healing of the ileoanal anastomosis does not appear to be adversely affected by the use of this technique. Because ultrasonic fragmentation is not dependent on the integrity of the submucosal plane, it may be advantageous in those cases in which severe inflammation and submucosal scarring make manual dissection of the rectal mucosa difficult to perform.

Echogenicity can be created by the admixture of any acoustically dissimilar substances. Experiments performed in vitro using mineral oil and water and in vivo examining 24 pathologically proven echogenic abnormalities show that echogenicity cannot be ascribed to a specific tissue, but rather is a property of all substances. In addition, when dissimilar histologic and pathologic substances have similar echo appearances and are adjacent, they become indistinguishable. This loss of structural definition can be termed the sonographic "masking sign," comparable in masking qualities to the established radiographic "silhouette sign." When this phenomenon occurs, an abnormality can be detected only through displacement of an organ or distortion of its internal anatomy. A thorough understanding of echogenicity and the sonographic masking sign will allow a more accurate evaluation of masses and infiltrating processes.

The surgical treatment of patients with familial polyposis coli and ulcerative colitis often requires removal of the rectum. Abdominoperineal resection, however, has a substantial morbidity. Ultrasonic fragmentation allows complete removal of the distal rectal mucosa with preservation of the surrounding muscularis. Ten adult mongrel dogs underwent ultrasonic mucosal proctectomy with resection of the proximal rectum and end colostomy. Two months later, the animals were sacrificed and the remaining rectum was removed and examined. The rectal remnant had shrunk and there was fibrous healing of the muscular wall with obliteration of the lumen. There was no mucosal regeneration. Ultrasonic mucosal proctectomy appears to achieve the same results as abdominoperineal resection of the rectum without the morbidity of the perineal dissection. This procedure may be useful in those patients where removal of the rectum is necessary for benign disease and endorectal pull-through is not indicated.

Mucosal proctectomy is becoming the operation of choice in the surgical treatment of patients with ulcerative colitis and familial polyposis coli. Dissection of the rectal mucosa and submucosa from the underlying muscularis is often difficult and, in some instances, impossible to perform. The feasibility of using an ultrasonic device to perform mucosal protectomy was studied in eight dogs. This technique produced coagulative necrosis of the mucosa and muscularis mucosa with marked edema and congestion of the submucosa. The muscularis propria remained intact. Complete destruction of the distal 7 cm of rectal mucosa required a total duration of exposure to the ultrasonic probe of at least 12 minutes. In another five dogs, total colectomy was performed above the area of the mucosal proctectomy followed by endorectal pull-through of the ileum. Follow-up studies revealed healing of the ileonal anastomosis without retraction or stricture. This technique should allow mucosal proctectomy to be performed in those patients in whom standard dissection is not possible due to fibrosis of the submucosal plane.

Several studies have shown that the presence of DNA ploidy abnormalities, measured by flow cytometry, may correlate with a poor prognosis in a variety of cancers. The predictive value of these DNA abnormalities in young patients with colorectal cancer has not been well studied. Fifty patients aged 40 years and younger with colorectal adenocarcinoma were studied to determine the correlation of tumor DNA abnormalities with survival. DNA content was determined by flow cytometric analysis and each tumor was categorized as diploid or nondiploid. Of the parameters studied, Dukes' classification and tumor DNA ploidy were found to be significant prognostic indicators. Determination of DNA content seems to provide additional useful prognostic information in young patients with colorectal cancer.

Mesenteric and retroperitoneal cysts are rare intra-abdominal tumors. Ten new patients are presented as well as 152 other cases reported in the English literature. These 162 cases were then analyzed for significant trends. Patients under 10 years of age were significantly different from the older group with respect to a shorter duration of symptoms, a higher number of patients requiring an emergency operation, a lower number of recurrences and the location of the cyst. Patients with retroperitoneal cysts were more likely to have incomplete excision of the cyst and therefore had a higher incidence of recurrence. They also required marsupialization more often. Retroperitoneal cysts should be considered a different entity from mesenteric cysts even though they present clinically in a similar fashion. The outcome of surgical treatment is less satisfactory in patients with retroperitoneal cysts.

In an attempt to identify factors contributing to survival of free fall and impact, we evaluated the records of four patients who survived a jump from the Brooklyn Bridge into the East River in New York Harbor between 1977 and 1985. All four patients were male and ranged in age from 22 to 67 years. They had free falls of between 41.0 and 48.8 meters. All of the patients were brought to the hospital within 24 minutes of entering the water. Three of the four had emergency surgical treatment and the fourth patient had only minor injuries. All four patients survived the suicide attempts. The length of the hospital stay ranged from two to 26 days.

All patients with gallstone ileus admitted to our institutions between 1938 and 1982 were retrospectively analyzed by grouping the patients into 10-year periods. Forty-five patients were studied, of whom 39 required operation. When hospital statistics for admissions, length of stay, and mortality rates from the Mount Sinai Hospital were compared to the gallstone ileus data, it was found that there has been no significant change in the admission rate for these patients. The mortality rate and length of stay of gallstone ileus patients has also remained constant over the past 25 years despite the general hospital decrease in both of these numbers. There has been no change in the complication rate, duration of symptoms prior to admission, or the preoperative diagnostic rate of gallstone ileus during the duration of this study.