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51.
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.  相似文献   
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We reviewed our recent experience with management of 23 consecutive patients with acute necrotizing pancreatitis. All patients had documented necrotizing pancreatitis with parenchymal or peripancreatic necrosis. Our method of treatment has evolved from our previous approach of controlled open lesser sac drainage (marsupialization) to staged necrosectomy/debridement with delayed primary closure over drains. With this latter approach, hospital mortality was 4 of 23 patients (17 per cent), but significant morbidity still occurred in 12 of 23 patients (52 per cent). However, recurrent intra-abdominal abscess before discharge occurred in only one patient. We believe that this operative approach toward the severely ill patient with acute necrotizing pancreatitis who requires operative intervention will minimize the occurrence of intra-abdominal sepsis.  相似文献   
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BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
56.
During the past decade, one of the most controversial issues in the surgical literature has been the question of what is the most appropriate management of splenic trauma. An increased understanding of the physiologic importance of splenic function must now be weighed against the life-threatening risk of exsanguinating splenic hemorrhage. In this article, postsplenectomy sepsis and mortality in adults and the selective management of blunt splenic trauma are discussed. Although the risks of postsplenectomy sepsis and serious infection are low, they do exist. A policy of individual assessment of cases is recommended when the merits of splenectomy versus those of splenic preservation are considered. Similarly, in cases of blunt splenic trauma, a policy of individual assessment is not only intellectually attractive but also safe, rational, and effective from a clinical standpoint. In selected cases of blunt splenic trauma, nonoperative management and splenorrhaphy are acceptable alternatives; however, in many instances splenectomy remains the most appropriate and only course of action.  相似文献   
57.

Objectives

The aim of the study was to describe the prevalence of and examine the factors associated with immunosuppression (CD4<200 cells/μL) among HIV‐infected patients attending two large inner London treatment centres.

Methods

Patients attending for care who had a CD4 count <200 cells/μL during a 6‐month period (1 January to 30 June 2007) were identified from the UK national CD4 surveillance database. Corresponding case notes were reviewed and factors associated with the most recent immunosuppressive episode examined. Patients either previously had a CD4 count >200 cells/μL at any time under follow‐up which had decreased (group A) or never had a CD4 count >200 cells/μL (group B; late presenters).

Results

Of 4589 patients, 10.2% (467) had at least one CD4 count <200 cells/μL. In group A (60.1% of patients), 70.4% were not receiving antiretroviral therapy (ART) at the time at which the CD4 count fell to <200 cells/μL. Reasons included: treatment interruption (TI; 32.6%), patient declined ART (20.2%), infrequent attendance (19.1%), physician delay in offer (23.1%) and transient CD4 cell count decrease (3.9%). Among those receiving ART, one in three had poor adherence. In group B, 92.3% had started ART after presentation: most had recently started and were responding virologically. AIDS‐defining diagnoses occurred in the year preceding the decrease in CD4 cell count in 12.6% of patients in group A and 33.3% of those in group B.

Conclusion

The majority of patients became immunosuppressed while under care. Our findings suggest that, in addition to strategies aimed at earlier diagnosis, there are further opportunities to reduce severe immunosuppression in patients already attending for HIV care.  相似文献   
58.
We attempted to quantify the protective potential of polyclonal IgG antibodies specific to the ectodomain of M2 protein (eM2) of influenza A virus (IAV) against lethal influenza infection of mice. For this purpose, eM2 conjugated with keyhole limpet hemocyanin (KLH) or KLH alone were administered with Freund's adjuvant intraperitoneally (i.p.) to BALB/c mice. IgG antibodies specific to the KLH-eM2 conjugate (anti-KLH-eM2 IgGs) and KLH (anti-KLH IgGs), respectively, were purified from ascitic fluids. Analysis of the preparation of anti-KLH-eM2 IgGs by ELISA revealed that it contained about 25% of anti-eM2 IgGs and 75% of anti-KLH IgGs. Taking into account this finding mice were passively immunized by intravenous route with 320, 160, 80, and 40 μg of anti-eM2 IgGs per mouse, respectively, while 320 μg of anti-KLH IgGs were used in control. Following subsequent infection with 3 LD50 IAV the survival of mice was determined. An absolute protection (100% survival) was obtained with 320 μg of anti-eM2 IgGs, and a relatively strong significant protection (~80% survival, p = 0.024) with 160 μg. The amount 160 μg of IgGs represents approx. 100 μg IgGs per 1 ml of blood.  相似文献   
59.
60.
Wood  GS; Garcia  CF; Dorfman  RF; Warnke  RA 《Blood》1985,66(5):1092-1097
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.  相似文献   
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