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81.
Hepatitis C virus (HCV) coinfection is common among individuals with HIV, and the progression of liver disease is accelerated in coinfected individuals compared with those with HCV alone. HCV coinfection also can decrease tolerability of highly active antiretroviral therapy. Additionally, the presence of HCV appears to increase morbidity and mortality in these individuals, and as such the management of both HCV and HIV in coinfected individuals requires careful consideration. Although coinfected patients should be considered for HCV therapy, the limited information to date indicates a lower rate of virologic response with current HCV therapies. Moreover, interactions between HCV and HIV antiviral medications may occur and potentially affect treatment efficacy. Thus, the decision to undertake HCV treatment must be individualized.  相似文献   
82.
The cause, or causes, of the vast majority of Alzheimer's disease cases are unknown. A number of contributing factors have been postulated, including infection. It has long been known that the spirochete Treponema pallidum, which is the infective agent for syphilis, can in its late stages cause dementia, chronic inflammation, cortical atrophy and amyloid deposition. Spirochetes of unidentified types and strains have previously been observed in the blood, CSF and brain of 14 AD patients tested and absent in 13 controls. In three of these AD cases spirochetes were grown in a medium selective for Borrelia burgdorferi. In the present study, the phylogenetic analysis of these spirochetes was made. Positive identification of the agent as Borrelia burgdorferi sensu stricto was based on genetic and molecular analyses. Borrelia antigens and genes were co-localized with beta-amyloid deposits in these AD cases. The data indicate that Borrelia burgdorferi may persist in the brain and be associated with amyloid plaques in AD. They suggest that these spirochetes, perhaps in an analogous fashion to Treponema pallidum, may contribute to dementia, cortical atrophy and amyloid deposition. Further in vitro and in vivo studies may bring more insight into the potential role of spirochetes in AD.  相似文献   
83.
The purpose of this clinical trial study was to report the outcome of intracytoplasmic injection of round (RS) and elongated (ES) spermatids retrieved from the testis of nonobstructive men. Seven and three cycles using RS and ES injections were performed, respectively. Only one cycle utilizing the late stage of ES (Sd2) resulted in an on-going pregnancy. The remarkable low success rate following RS microinjection was established in this study.  相似文献   
84.
85.
OBJECTIVE: Our study sought to describe the MR imaging features and the patterns of spread in secondary tumor involvement of the uterus by nonuterine tumors. CONCLUSION: Direct extension of an adjacent tumor to the uterus is the most common pattern of secondary tumor involvement. Concomitant invasion of other pelvic organs is also typical. Although less common, hematogenous or lymphatic metastases to the uterus are encountered in clinical practice. Metastases should be added to the differential diagnosis of apparently malignant masses in the uterine body or cervix, especially in patients with metastatic disease or in patients whose uterus shows a preserved shape with involvement by an infiltrative heterogeneously enhancing process.  相似文献   
86.
The structure-based design, synthesis, and biological activity of a novel indazole-containing inhibitor series for S-adenosyl homocysteine/methylthioadenosine (SAH/MTA) nucleosidase are described. Use of 5-aminoindazole as the core scaffold provided a structure-guided series of low nanomolar inhibitors with broad-spectrum antimicrobial activity. The implementation of structure-based methodologies provided a 6000-fold increase in potency over a short timeline (several months) and an economy of synthesized compounds.  相似文献   
87.
Portal vein thrombosis (PVT) following splenectomy is a potentially life-threatening complication, and the true incidence of PVT in splenectomized patients is unknown. The objective of this study was to determine the incidence of symptomatic PVT after splenectomy. The hospital database was searched to identify cases of PVT associated with splenectomy from January 1990 to May 2002. Six hundred eighty-eight patients underwent splenectomy during this period, 321 of them for hematologic diseases. Eleven of the 688 patients had PVT associated with splenectomy, and the charts of these patients were reviewed. Six patients developed PVT after splenectomy. Five had hematologic diseases. Symptoms were abdominal pain (6), ileus (5), fever (3), or diarrhea (2). Diagnosis was confirmed by computed tomography (CT) (4), duplex ultrasonography (1), and magnetic resonance imaging (1). The indications for splenectomy included hemolytic anemia (3), thalassemia (1), and myelofibrosis (1). One patient had an incidental splenectomy during gastrectomy. There were four laparoscopic and two open splenectomies. The median interval between splenectomy and diagnosis of PVT was 40 days (range, 13-741). One patient died of pulmonary embolism. Five of six patients with postsplenectomy PVT had splenomegaly and hemolysis. We conclude that the risk of PVT is higher in patients with hematologic conditions associated with splenomegaly and hemolysis.  相似文献   
88.
A group of 3'-O-nitro-2'-deoxyuridines, 3'-O-nitro-2'-deoxycytidines, and 5'-O-nitro-2'-deoxyuridines possessing a variety of substituents (H, Me, F, I) at the C-5 position were synthesized for evaluation as anticancer/antiviral agents that have the ability to concomitantly release cytotoxic nitric oxide (*NO). Although these compounds generally released a greater percent of *NO than the reference drug isosorbide dinitrate upon incubation in the presence of l-cysteine, or serum, their cytotoxicity (CC(50) = 10(-3) to 10(-6) M range) was comparable to 5-iodo-2'-deoxyuridine, but weaker than 5-fluoro-2'-deoxyuridine, against a variety of cancer cell lines. No differences in cytotoxicity against nontransfected (KBALB, 143B), and the corresponding transfected (KBALB-STK, 143B-LTK) cancer cell lines possessing the herpes simplex virus type 1 (HSV-1) thymidine kinase gene (TK(+)) were observed, indicating that expression of the viral TK enzyme did not provide a gene therapeutic effect. These nitrate esters were inactive antiviral agents except for 5-iodo-3'-O-nitro-2'-deoxyuridine that showed modest activity against HSV-1, HSV-2, and vaccinia virus.  相似文献   
89.
JC virus (JCV) is a polyomavirus infecting greater than 80% of the human population early in life. Replication of this virus in oligodendrocytes and astrocytes results in the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML) in immunocompromised individuals, most notably acquired immunodeficiency syndrome (AIDS) patients. Moreover, recent studies have pointed to the association of JCV with a variety of brain tumors, including medulloblastoma. The JCV genome encodes for viral early protein, including large and small T antigens and the newly discovered isoform T', at the early phase of infection and the structural proteins VP1, VP2, and VP3 at the late stage of the lytic cycle. In addition, the late gene is responsible for the production of a small nonstructural protein, agnoprotein, whose function is not fully understood. Here, we have summarized some aspects of the JCV genome structure and function, and its associated diseases, including PML and brain tumors.  相似文献   
90.
Introduction: Increased stress levels have been reported and it has been implicated for mental illness amongst service personnel. However no study has been reported among Indian naval sailors.  相似文献   
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