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Graefe's Archive for Clinical and Experimental Ophthalmology - To estimate the impact of delayed care during the coronavirus disease 2019 (COVID-19) pandemic on the outcomes of patients with...  相似文献   
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Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement.
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma.  相似文献   
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Four years of data are reported on the drug cost avoidance and the net cost savings associated with a clinical pharmacy intervention program. In 1986 the pharmacy department at a 324-bed nonprofit community medical center began a clinical intervention program by adding one full-time equivalent for providing clinical services. A new clinical pharmacist position was created in 1988. A reorganization in 1989 resulted in further increases in staffing, including the creation of a clinical coordinator position to oversee the intervention program, and in administrative time. Staff pharmacists self-report a broad range of interventions on a clinical documentation form. During the period 1986-1989, monthly data on the number of types of interventions recommended, the percentage of recommendations accepted by the medical staff, and drug cost avoidance were tabulated. Cost avoidance was calculated by subtracting the cost of therapy ordered by the physician from the cost of therapy initiated as a result of the intervention. Net drug cost savings were calculated by subtracting from cost avoidance the cost of pharmacist time required for performing the interventions. The average number of interventions per month ranged from 170 in 1986 to 292 in 1990. During an 18-month period before the clinical coordinator was added, average monthly cost avoidance and net savings were $4932 and $3739, respectively. Average monthly cost avoidance increased to $6244 and savings to $4644 in a 12-month period after the clinical coordinator was added. A four-year study of a clinical intervention program showed that the dollar value and impact outlasted the initial success expected for such programs.  相似文献   
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BACKGROUND: The purpose of this study was to analyze the frequency and results of preoperative biliary and gastrointestinal (GI) evaluation of patients undergoing Roux-en-Y gastric bypass (RYGB). METHODS: Retrospective review of the preoperative evaluation of 144 consecutive RYGB patients. RESULTS: Cholecystectomy had already been performed in 43 (30%) patients; 22% of those patients with an intact gallbladder had cholelithiasis. Ten patients (7%) had an upper GI x-ray (UGI), and 94 patients (65%) had an esophagogastroduodenoscopy (EGD). Abnormalities were found in 40% of the UGIs and 84% of the EGDs. A total of 96 patients (67%) were tested for Helicobacter pylori; 11% were positive. Twenty-one patients (15%) underwent preoperative colonoscopy; 48% were abnormal, but most of the abnormalities were not clinically significant. Three patients had barium enema x-ray, which was normal in all cases. CONCLUSIONS: The preoperative biliary and GI evaluation of bariatric surgery patients should include a routine ultrasound of the gallbladder. Routine preoperative EGD will detect a significant number of abnormalities that should be treated, but should rarely alter the bariatric surgical procedure or result in denial of bariatric surgery. Many abnormalities will be asymptomatic. Patients should be routinely screened for H. pylori and, if positive, treated before bariatric surgery. Lower GI evaluation should be performed selectively based on the patient's symptoms, physical findings, and guidelines for colorectal cancer and polyp screening.  相似文献   
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Data from the National AIDS Behavioral Survey were used to examine the social distribution of extramarital sex and risk for human immunodeficiency virus (HIV) infection among married individuals in the United States. Of 1686 married respondents living across the United States, 2.2% reported extramarital sex; of 3827 married respondents living in 23 urban areas with large Hispanic or African-American populations, 2.5% reported having sexual partners outside marriage. The data indicate that the correlates of extramarital sex varied by race/ethnicity. Low levels of condom use were found among people reporting extramarital sex (8% to 19% consistent users).  相似文献   
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Total agenesia of the left pericardium is an uncommon congenital anomaly. The case of a 20-year-old male patient practising sports and complaining of atypical chest pain is described. The Authors point out the importance of the particular ECG and Rx findings obtained varying the patient's supine position. The fundamental role of chest CAT scanning as a non-invasive diagnosis technique is confirmed.  相似文献   
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