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101.
Ovarian cancer is the seventh most common cancer diagnosis among women worldwide. The International Federation of Gynecology and Obstetrics recently significantly revised staging criteria for cancer of the ovary. The latest revision was based on the concept that high-grade serous tubal intraepithelial carcinoma (STIC) may be the origin of some high-grade serous carcinomas of the ovary and peritoneum. Therefore, staging criteria for the ovary, fallopian tube, and peritoneum have been unified. Understanding this background and other important revised points are essential for radiologists concerned with imaging diagnosis in gynecologic oncology. Through this review, we introduce the STIC theory and show examples of diseases in accordance with the new staging criteria based on magnetic resonance imaging (MRI) and computed tomography (CT) results.  相似文献   
102.
103.

Background

Reoperative parathyroidectomy (RPTX) because parathyroid glands have been missed is frequently required in patients with secondary hyperparathyroidism (SHPT). The usual locations of these missed glands in patients with SHPT are yet to be fully elucidated.

Methods

We retrospectively investigated the locations of missed glands in 165 patients who underwent RPTX for persistent or recurrent SHPT at our institution from August 1982 to July 2014. At our institution, total parathyroidectomy with forearm autograft is the routine operative procedure for SHPT. We also routinely resect the thymic tongue.

Results

Of 165 patients, 82 underwent initial parathyroidectomy at our institution (Group A), and the remaining 83 underwent initial parathyroidectomy at other institutions (Group B). A total of 239 parathyroid glands were resected (Group A, 93; Group B, 146). Missed glands were most commonly located in the mediastinum (Group A, 22/93) and the thymic tongue (Group B, 31/146).

Conclusions

In patients with persistent or recurrent SHPT, ectopic parathyroid glands are frequently located in the mediastinum and thymic tongue. Therefore, resecting the thymic tongue during the initial operation may reduce the need for RPTX.
  相似文献   
104.

Background

Persistent hyperparathyroidism (HPT) after renal transplantation (RTx), termed tertiary HPT (THPT), is not uncommon. However, risk factors and appropriate operative procedures for THPT are poorly understood.

Methods

A retrospective study of patients who underwent RTx without pre-transplant parathyroidectomy (PTx) was performed at our hospital between January 2001 and March 2011. Risk factors for the development of THPT were investigated by comparing THPT and non-THPT groups. We retrospectively analyzed patients with THPT who underwent total PTx with forearm autograft. Pre- and postoperative (1 year after PTx) laboratory results were analyzed for PTx efficacy.

Results

Data for 520 patients were analyzed. On multivariate analysis, long dialysis duration (p = 0.009, hazard ratio (HR) 1.01), large maximum parathyroid gland size before RTx (p = 0.003, HR 1.23), pre-RTx high intact parathyroid hormone (iPTH) (p = 0.041, HR 1.01), post-RTx (<2 weeks) high calcium (Ca) (p < 0.001, HR 25.04), and post-RTx high alkaline phosphatase (ALP) (p = 0.027, HR 0.99) were identified as risk factors for THPT. Patients who underwent PTx showed significant improvement compared with baseline for serum Ca, phosphorus, iPTH, and ALP. Serum creatinine showed no significant difference.

Conclusions

Several risk factors for THPT development were identified. PTx for patients with THPT significantly improved serum Ca, iPTH, ALP, and phosphorous levels. There was no significant difference in renal function after PTx. Therefore, total PTx with forearm autograft may be an appropriate surgical approach for patients with THPT.
  相似文献   
105.
106.

Background

Some studies have reported causal associations between bacteremia and mortality or allograft loss in kidney transplant recipients (KTR). However, few studies have assessed the clinical course of kidney function and the risk of acute allograft rejection after bacteremia.

Methods

We retrospectively reviewed 902 kidney transplants performed at Nagoya Daini Red Cross Hospital between January 1, 2002 and March 31, 2014. Forty-five living donor kidney transplant recipients with single bacteremia were included. We analyzed death, change in kidney function, and development of acute allograft rejection 12 months after bacteremia according to the following groups: primary source of bacteremia (urinary tract or other sources), site of acquisition (community acquired or nosocomial), severity (not meeting the systemic inflammatory response syndrome criteria and sepsis or severe sepsis and septic shock), empiric antibiotic use (appropriate or inappropriate), and baseline kidney function (estimated glomerular filtration rate ≤44.7 or ≥44.8 ml/min).

Results

Urinary tract infection (UTI) was the leading cause of bacteremia (68.9 %), and Escherichia coli was the most common pathogen. Three cases (6.7 %) died of infection that caused bacteremia within 12 months. Pneumonia accounted for two-thirds. Kidney function declined 1 week after bacteremia (P < 0.05), particularly in severe cases. Thereafter, kidney function was comparable to baseline level in each group (P ≥ 0.05). Severe UTI was associated with subsequent acute allograft rejection (P = 0.03).

Conclusions

Pneumonia in KTR should be managed with caution. Kidney function generally returned to baseline level after bacteremia. However, severe UTI may be associated with subsequent acute allograft rejection.
  相似文献   
107.
Previous studies indicate that long-term dietary supplementation with arachidonic acid (AA) in 20-month-old rats (OA) effectively restores performance in a memory task and the induction of long-term potentiation in the hippocampus to the level of young control animals (YC). The present study examined protein mobility using the live cell imaging technique "Fluorescent Recovery After Photobleaching (FRAP)" in YC, old control (OC) and OA neurons in hippocampal slice preparations. Three measures; mobile fraction (M(f)), diffusion constant (D) and time constant (tau), were estimated among YC, OC and OA. Each of these parameters was significantly different between OC and YC, suggesting that membrane fluidity is lower in OC than in YC. In contrast, D and tau were comparable in OA and YC, indicating that hippocampal neuronal membranes supplemented with AA were more fluid than those in OC, whereas the fraction of diffusible protein in the bleached region remained smaller than in YC. Long-term administration of AA to senescent rats might help to preserve membrane fluidity and maintain hippocampal plasticity.  相似文献   
108.
109.
To investigate plastic changes in nociceptive sensitivity of the dorsal horn, slow excitatory responses elicited by iteration of high-frequency stimulation were spatiotemporally observed in spinal cord slices of young-adult rats using membrane excitation imaging techniques. Single-pulse stimulation to the dorsal root elicited membrane excitation in lamina II, and high-frequency pulse-train stimulation evoked long-lasting excitation that expanded widely in the dorsal horn. Iteration of high-frequency stimulation enhanced the strength and extent of the excitatory responses, but such augmentation of the excitatory responses disappeared in the presence of an NMDA receptor antagonist (CPP) and was hindered by an NK1 receptor antagonist (L-703.606). The results suggest that activation of both NMDA and NK1 receptors is involved in the enhancement of slow excitatory responses evoked by iteration of high-frequency stimulation.  相似文献   
110.
Contact hypersensitivity (CHS) is a cutaneous immune reaction mediated mainly by antigen-specific effector T cells and is regarded as a model for Th1/Tc1-mediated inflammation. However, recent reports have suggested pivotal roles of B cells in CHS. CD19 serves as a positive B-cell response regulator that defines signaling thresholds critical for B-cell responses. In the current study, we assessed the role of the B-cell-specific surface molecule CD19 on the development of CHS by examining CD19-deficient mice. Although CD19-deficient mice are hyposensitive to a variety of transmembrane signals, CD19 loss resulted in increased and prolonged reaction of CHS, suggesting an inhibitory role of CD19 expression in CHS. Sensitized lymph nodes and elicited ear lesions from CD19-deficient mice exhibited Th1/Tc1-shifted cytokine profile with increased interferon-gamma expression and decreased interleukin-10 expression. Adoptive transfer experiments revealed that CD19 expression in recipient mice was required for optimal suppression of CHS response, indicating its role in the elicitation phase. Furthermore, spleen B cells, especially marginal zone B cells, from wild-type mice were able to normalize exaggerated CHS reactions in CD19-deficient mice. Thus, CD19 expression in B cells is critical for termination of CHS responses, possibly through the function of regulatory B cells.  相似文献   
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