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101.
One hundred twenty-one patients with extrahepatic biliary obstruction underwent endoscopic sphincterotomy (EST). This was followed by balloon occlusion catheter or dormia basket stone extraction in 106 patients with choledocholithiasis, and by transpapillary biliary endoprosthesis placement in 15 patients with malignant distal common bile duct obstruction. All patients had excellent biliary decompression. Complications not requiring surgical intervention were seen in six patients. This article shows that EST is a low-risk, effective therapy for benign and malignant extrahepatic biliary obstruction.  相似文献   
102.
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
103.
The serum kinetics of an intravenous bolus of a combination of ticarcillin (TIC) (3 g) and clavulanic acid (CLAV) (0.2 g) have been determined in a number of patients with different degrees of renal failure as characterized by creatinine clearance. The volume of distribution for both drugs was unaffected by renal failure. Indices of serum and renal drug clearance were related to the degree of renal failure. TIC was cleared more slowly than CLAV. Anephric patients may have a higher serum clearance of CLAV than patients categorized by creatinine clearance as having severe renal failure; this could be due to an increase in metabolic clearance. Haemodialysis effectively clears both drugs. "Rebound" serum concentrations were consistently observed for TIC, but were observed in only one patient for CLAV. Continuous ambulatory peritoneal dialysis results in significant recovery of both drugs. The dosing requirements for the combination of TIC and CLAV in patients with renal failure are considered.  相似文献   
104.
With the use of age-adjusted incidence rates and proportional incidence ratios, investigators studied the risk of cancer of the stomach and 3 subdivisions of the large bowel in three race-ethnic groups--Spanish surnamed whites, other whites, and Japanese--and compared Los Angeles County native residents, immigrants, and representative "homeland" populations. The risk pattern for each of the four anatomic sites was quite distinctive, suggesting at least four different etiologic complexes. For each site the observed gradients of risk are nearly identical for each sex, usually with risk for immigrants intermediary between that for homeland residents and that for local natives; the differences between race-ethnic groups are consistent with known international patterns. Particularly notable is the contrast between the low risks of cancer of both the sigmoid and the rectum in Japan and the high risks for Japanese immigrants to Los Angeles, which are nearly double those of their U.S. white neighbors. In all instances, and especially for both the upper and lower colon, the influence of the adult environment predominates over that of the early environment. The environmental determinants of stomach cancer do not always appear in inverse correlation with those of colon cancer, since Japanese immigrants to Los Angeles and their descendants are at high absolute and relative risk of both neoplasms. Our findings suggest that patterns of risk in relation to migration are complex and defy simple dietary or other interpretation. Without more information about the impact of migration to the United States on qualitative and quantitative aspects of lifestyle, it is not possible to put forward simple hypotheses that explain all available facts.  相似文献   
105.
Seventy three patients with disseminated diffuse non-Hodgkin's lymphomas were treated with combinations of cyclophosphamide, vincristine sulfate, prednisone, and doxorubicin with and without 2 weekly doses of oral methotrexate in "intermediate" doses, followed by calcium leucovorin rescue. The addition of methotrexate did not increase the complete remission rate, the remission duration, or the survival (P value = 1.0, 0.74, and 0.78, respectively) in patients who did not have previous chemotherapy treatment. In previously treated patients, the complete remission rate was somewhat higher and the remission duration and survival were longer among those patients treated with the methotrexate containing program; however these differences were not statistically significant (P values = 0.88, 0.81, and 0.46, respectively). There was substantial morbidity and mortality during treatment with both treatment arms, among patients aged more than 60 years.  相似文献   
106.
Maternal and Child Health Journal - Mothers are especially vulnerable to the onset or recurrence of psychological symptoms during the postpartum period. However, protective psychosocial factors may...  相似文献   
107.
IntroductionAttrition in pediatric weight management programs is notoriously high. Greater understanding of its determinants is needed to inform retention strategies. We identified determinants of attrition in CIRCUIT, a healthy lifestyle intervention program for youth at risk of cardiovascular disease.MethodsA one-arm intervention study of children aged 4-18 years who initiated the CIRCUIT program in the first five years of its existence (N = 403). We defined attrition as attending the baseline visit but ceasing attendance prior to the 1-year follow-up. Potential determinants of dropout included the child’s age, sex, ethnicity, body mass index (BMI) z-score, family socio-demographic characteristics, and estimated driving time to the program, all measured at baseline. Associations were estimated bivariately, using chi-squared- and t-tests, and simultaneously in a multivariable logistic regression model.ResultsOf the 403 participants who started the program, 198 (49%) dropped out within 12 months of enrollment. Youth who dropped out were older (mean age 12.8y vs. 11.3y; p < 0.01), were less likely to live with both parents (62% vs. 71%; p = 0.05), and to have mothers who had completed high school (79% vs. 88%; p = 0.01). No group differences were observed for sex, ethnicity, baseline BMI z-score, fathers’ education, or driving time to the program. In multivariate models, only older age at initiation of the intervention (OR: 1.2; CI: 1.1,1.3) and lower maternal education (OR: 2.0; CI: 1.0,3.8) were associated with dropout.ConclusionImproved tailoring of interventions to older pediatric participants and to families of lower maternal education may help reduce attrition in CIRCUIT and similar lifestyle intervention programs.  相似文献   
108.
109.
Twins: a test of the equal environments assumption   总被引:1,自引:0,他引:1  
We asked a sample of 343 adult same-sex twin pairs a number of questions about the similarity of their social environment during childhood and early adolescence. A factor analysis of their responses indicated that their common environment was derived from two sources, one being similar treatment "imposed" upon them by their parents, the other being "elicited" by the twins' similar interests and behavior. Monozygotic (MZ) twins reported experiencing more similar "imposed" and "elicited" environments than dizygotic (DZ) twins. The extent of imposed similar treatment received during childhood and early adolescence was unrelated to either MZ or DZ twins' current behavioral similarity, as indicated by absolute intrapair differences in their Neuroticism, Anxiety, and Depression scores. Similar treatment imposed upon MZ twins on the basis of their zygosity alone is therefore not a threat to the validity of the twin method.  相似文献   
110.
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