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111.
Post exercise lymphocytopenia is well documented and attributed to egress of lymphocytes from the vascular compartment. Recent studies have reported exercise induced DNA damage in leukocytes and have questioned a possible link to apoptosis. Eleven subjects underwent a ramped treadmill test to exhaustion. Venous blood samples were taken before, immediately post exercise, and 24 and 48 hours after exercise. Single cell gel electrophoresis revealed evidence of single strand DNA damage in 10% of lymphocytes immediately after exercise, but not at other times. Fluorescent microscopy showed three patterns of DNA distribution, similar to those seen in apoptosis, at all times after exercise. Three subjects underwent the same exercise protocol, and lymphocytes were prepared for flow cytometry to determine apoptosis using the TUNEL method. Flow cytometry revealed lymphocyte apoptosis in 63% of lymphocytes immediately after exercise and 86.2%, 24 hours after exercise. Lymphocyte apoptosis is documented for the first time after exercise and may in part account for exercise induced lymphocytopenia and reduced immunity.  相似文献   
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PURPOSE: In this study, we sought to determine the outcome of patients with ischemic colitis, comparing patients with segmental disease with those with total colonic ischemia. METHODS: Patients with the diagnosis of ischemic colitis over the past six years were selected and reviewed for demographics, presenting symptoms, diagnosis, and treatment. RESULTS: Forty-three consecutive patients with ischemic colitis were identified and were grouped into those with segmental ischemic colitis and total colonic ischemia. Mean age was 68.8 years; 28 of 43 patients (65 percent) were males. Diagnosis was established by colonoscopy in 31 of 43 patients (72 percent), whereas in the remainder, diagnosis was made in the operating room. Ischemic colitis developed in the hospital in 17 of 43 patients (40 percent) during admission for an unrelated illness. In 6 of 43 (14 percent) of these patients, ischemic colitis developed following surgery. Thirty-one of 43 patients (72 percent) were found to have segmental colitis; 11 of 31 patients (35 percent) were successfully managed nonoperatively. Segmental colitis was present in 31 of 43 patients (72 percent), and 12 of 31 (35 percent) of these patients were successfully managed nonoperatively. In the patients with segmental colitis who required surgery, the 30-day mortality rate was 22 percent. Among 12 of 17 patients (71 percent) with segmental ischemia treated by resection and stoma, 9 of 12 (75 percent) underwent eventual stoma closure. All 12 patients with total colonic ischemia required surgery, and 9 of 12 patients (75 percent) died. CONCLUSION: Ischemic colitis occurs commonly during an unrelated hospital admission and following previous surgery. Most patients treated by resection and stoma undergo stoma closure. Total colonic ischemia carries a worse prognosis than segmental colonic ischemia.  相似文献   
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Genes of an influenza A (H5N1) virus from a human in Hong Kong isolated in May 1997 were sequenced and found to be all avian-like (K. Subbarao et al., Science 279:393-395, 1998). Gene sequences of this human isolate were compared to those of a highly pathogenic chicken H5N1 influenza virus isolated from Hong Kong in April 1997. Sequence comparisons of all eight RNA segments from the two viruses show greater than 99% sequence identity between them. However, neither isolate's gene sequence was closely (>95% sequence identity) related to any other gene sequences found in the GenBank database. Phylogenetic analysis demonstrated that the nucleotide sequences of at least four of the eight RNA segments clustered with Eurasian origin avian influenza viruses. The hemagglutinin gene phylogenetic analysis also included the sequences from an additional three human and two chicken H5N1 virus isolates from Hong Kong, and the isolates separated into two closely related groups. However, no single amino acid change separated the chicken origin and human origin isolates, but they all contained multiple basic amino acids at the hemagglutinin cleavage site, which is associated with a highly pathogenic phenotype in poultry. In experimental intravenous inoculation studies with chickens, all seven viruses were highly pathogenic, killing most birds within 24 h. All infected chickens had virtually identical pathologic lesions, including moderate to severe diffuse edema and interstitial pneumonitis. Viral nucleoprotein was most frequently demonstrated in vascular endothelium, macrophages, heterophils, and cardiac myocytes. Asphyxiation from pulmonary edema and generalized cardiovascular collapse were the most likely pathogenic mechanisms responsible for illness and death. In summary, a small number of changes in hemagglutinin gene sequences defined two closely related subgroups, with both subgroups having human and chicken members, among the seven viruses examined from Hong Kong, and all seven viruses were highly pathogenic in chickens and caused similar lesions in experimental inoculations.  相似文献   
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Managed care continues to revolutionize the provision of mental health services in the United States. Long-term, open-ended therapies have been replaced by short-term, highly focused interventions. Increasingly, managed care organizations rely on standardized preferred practice guidelines to give direction and focus to social work and other therapeutic interventions. Critics argue that changes effected by managed care, particularly the use of treatment guidelines, depersonalize the client-worker relationship and significantly reduce the role of empathy in the therapeutic process. Moreover, these critics suggest that overall client satisfaction with mental health services has deteriorated. This article presents a study that examined clients' perceptions of empathy and overall satisfaction with managed behavioral health care when the clients were in unstructured individual therapy or in time-limited standardized group therapy. The results reveal no significant difference in the clients' perception of empathy or of their overall satisfaction regardless of the type of treatment they received. This article describes the rationale and design of the study, presents the results, and discusses the implications for social work practice.  相似文献   
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OBJECTIVES: Bile leaks are a well documented complication of biliary surgery, occurring more frequently with laparoscopic procedures. Endoscopic therapy with a long biliary endoprosthesis traversing the site of the leak is effective. We have evaluated the hypothesis that equalizing biliary and duodenal pressures with a short transpapillary stent is an equally effective therapy for bile leaks. METHODS: Thirty one consecutive patients presenting over a 52-month period with postsurgical bile leaks were evaluated. Patients had been treated with long endoprostheses (stents or nasobiliary tubes), sphincterotomy, or short transpapillary stents. The success, complication rate, need for additional therapy, and hospitalization time of each therapeutic approach were determined. RESULTS: Endoscopic therapy was successful in all 25 patients in whom a bile leak could be documented. The clinical success, need for radiological drainage, length of hospitalization, and incidence of pancreatitis were similar for all methods of treatment. CONCLUSIONS: These results confirm that endoscopic therapy is highly successful in the treatment of postoperative bile leaks and suggest that the mechanism of healing is the equalization of bile duct and duodenal pressures, allowing flow of bile into the duodenum. The endoscopic placement of short transpapillary stents without sphincterotomy is a temporary, effective, and technically simple method of pressure equalization. This should be considered as the primary therapy for most postoperative bile leaks.  相似文献   
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When stimulated through their antigen receptor without requisite costimulation, T cells enter a state of antigen-specific unresponsiveness termed anergy. In this study, signaling through the common gamma chain of the interleukin-2 (IL-2), IL-4, and IL-7 receptors in the presence of antigen was found to be sufficient to prevent the induction of anergy. After culture with IL-2, IL-4, or IL-7, Jak3 kinase was tyrosine-phosphorylated, which correlated with the prevention of anergy. Therefore, a signal through the common gamma chain may regulate the decision of T cells to either clonally expand or enter a state of anergy.  相似文献   
118.
Estrogen regulates the hepatic synthesis of a variety of proteins required for egg yolk production in oviparous vertebrates. In chickens, two of these proteins, apolipoprotein (apo) B and apoII, comprise the major protein components of specialized very low density lipoprotein particles that transport triacylglycerols and cholesterol to the developing egg yolk. In the adult, apoB is synthesized constitutively in liver, small intestine, and kidney but is estrogen-responsive only in the liver. In this work we have examined the embryonic expression of the apoB and apoII genes in yolk sac, liver, kidney, and small intestine. The 14 kb apoB mRNA was first detected at day 3 of development in vascular yolk sac, a tissue involved in the transfer of yolk lipids into the embryonic circulation. Constitutive apoB mRNA expression was detectable in liver at day 6.5 and in kidney at day 7.5, but in intestine was barely detectable before hatching. The hepatic apoB gene acquired estrogen-responsiveness at day 6.5 and its hormone-dependent expression increased throughout development in concert with the estrogen-responsive expression of the apoII gene. In contrast, the constitutively expressed apoB gene in kidney remained unresponsive to estrogen. Surprisingly, the apoII gene was found to be responsive to estrogen in both the embryonic kidney and small intestine. ApoII mRNA induction by estrogen in kidney at day 11 was at 10% of the level in the liver but estrogen-responsiveness decreased later in development and was low in the adult.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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