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71.
Fast MR imaging in obstetrics.   总被引:8,自引:0,他引:8  
Ultrasonography (US) is the initial imaging modality of choice for evaluation of patients in obstetrics. However, the results of US are not always sufficient. Magnetic resonance (MR) imaging, which uses no ionizing radiation, may be an ideal method for further evaluation. Although MR imaging is not recommended during the first trimester and use of contrast material is not recommended in pregnant patients, fast MR imaging is useful in various obstetric settings and can provide more specific information with excellent tissue contrast and multiplanar views. In pregnant patients with acute conditions, various diseases (eg, red degeneration of a uterine leiomyoma) may be diagnosed. MR imaging allows characterization of pelvic masses discovered during pregnancy and diagnosis of postpartum complications (eg, abscess, hematoma, ovarian vein thrombosis). In pregnant patients with hydronephrosis, MR urography can demonstrate the site of obstruction and the cause (eg, a ureteral stone). MR pelvimetry may be beneficial in cases of breech presentation. Contrast material-enhanced dynamic MR imaging allows one to evaluate the vascularity of a placental polyp, detect the viable component of a gestational trophoblastic tumor, and diagnose a uterine arteriovenous malformation. MR imaging enables diagnosis of rare forms of ectopic pregnancy and early diagnosis of ectopic pregnancy.  相似文献   
72.
BACKGROUND: Hemodialysis patients have advanced arterial wall stiffening as shown by increased aortic pulse wave velocity (PWV), an independent predictor of cardiovascular mortality. We compared aortic PWV of uremic patients before starting hemodialysis treatment with that of patients on maintenance hemodialysis. METHODS: The subjects were 71 patients with end-stage renal disease (ESRD) before starting hemodialysis (predialysis group), 144 patients on maintenance hemodialysis, and 140 healthy control subjects. These three groups were all nondiabetic and comparable in age and gender. RESULTS: The hemodialysis group had greater aortic PWV than the healthy subjects, and the predialysis patients showed a still higher value than the hemodialysis group. Multiple regression analysis in the total subjects revealed that the presence of renal failure was significantly associated with increased aortic PWV independent of age, gender, blood pressure, body mass index, smoking, high-density lipoprotein (HDL) and nonhigh-density lipoprotein (non-HDL) cholesterol levels. In contrast, hemodialysis was associated with decreased aortic PWV independent of renal failure and the other factors. Further analyses in the combined uremic patients again indicated the favorable impact of hemodialysis on aortic PWV independent of the classical risk factors, use of antihypertensive medications, including angiotensin-converting enzyme inhibitors and calcium channel blockers, hematocrit, serum calcium, phosphorus, parathyroid hormone levels, and the use of calcium carbonate. Insulin resistance using homeostasis model assessment (HOMA-IR) was associated with increased aortic PWV. CONCLUSION: Aortic stiffening was present in uremic patients before starting hemodialysis treatment and no adverse effect of hemodialysis was observed, suggesting the important roles of renal failure and/or metabolic alterations secondary to renal failure in arterial stiffness in patients with uremia.  相似文献   
73.
A 41-year-old man presented with progressive worsening of postural headache. Computed tomography (CT) showed bilateral subdural hematomas without prior history of trauma. The diagnosis was spontaneous intracranial hypotension (SIH). Conservative treatment with oral steroids failed to prevent gradual deterioration of the patient's consciousness. CT myelography revealed massive cerebrospinal fluid (CSF) leakage between the C-1 and C-2 levels. The leak was repaired surgically via a laminectomy. A cyst, thought to be a meningeal cyst, was discovered adjacent to the right C-2 nerve root, and CSF was seen seeping out from around the cyst after a Valsalva maneuver. The presumed dural defect of the cyst was sealed by packing with muscle fragments and fibrin glue. The symptoms disappeared soon after surgery. He was discharged 1 month after surgery without deficits. Most SIH cases are benign and can be managed conservatively, or by the epidural blood patch method. Surgery is more invasive than the epidural blood patch method, but should be performed in patients with a high cervical lesion and massive CSF leakage.  相似文献   
74.
Terada T 《The Prostate》2012,72(10):1150-1156
Because there have been no reports on the incidence and expressions and mutations of KIT and PDGFRA in small cell neuroendocrine carcinoma (SCNEC) of the prostate, the author surveyed archival specimens of 2,642 prostatic specimens (biopsy, 1,503 cases; transurethral resection, 1,009 cases; prostatectomy, 130 cases). Of these, 706 cases were malignant tumors. In equivocal cases (n = 16) of Gleason 5 adenocarcinoma resembling SCNEC, several neuroendocrine markers were immunohistochemically examined. As the results, four cases of SCNEC were identified; therefore the incidence of SCNEC was 0.5% of all prostatic malignancies. All the four cases were biopsies. The remaining 686 cases were adenocarcinomas. In case 1 (50 years of age), the SCNEC tumor cells were positive for cytokeratin, P504S, synaptophysin, KIT, and PDGFRA, but negative for PSA, neuron specific enolase, CD56, and TTF‐1. In case 2 (70 years of age), the tumor cells were positive for cytokeratin, PSA, P504S, chromogranin, and synaptophysin, but negative for neuron‐specific enolase, CD56, TTF‐1, KIT, and PDGFRA. In case 3 (72 years of age), the SCNEC tumor cells were positive for cytokeratin, PSA, P504S, synaptophysin, CD56, KIT, and PDGFRA, but negative for neuron‐specific enolase, chromogranin, and TTF‐1. In case 4 (81 years of age), the SCNEC tumor cell were positive for cytokeratin, PSA, P504S, chromogranin, synaptophysin, neuron‐specific enolase, KIT, and PDGFRA, but negative for CD56 and TTF‐1. A molecular genetic analysis using PCR‐direct sequencing showed no mutations of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) genes in three informative cases of SCNEC. The present cases were the first of prostatic SCNEC with an examination of KIT and PDGFRA expression and KIT and PDFGRA gene mutations. Prostate 72:1150–1156, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
75.
Many approaches for resection of the superior mediastinal tumors have been reported. We introduce an approach, which we call the cervical anterior approach. This approach is only cervical and does not require a sternotomy. Merits of this approach include the ability to remove the tumor without opening the mediastinal or parietal pleura, as well as obviating draining the thoracic cavity. The tumor is also directly visible, and the surgeon can avoid injury to the great vessels. This approach is recommended when the tumor is located superior to the third thoracic vertebra level, when it borders the great vessels, and when it does not border the trunk of the brachial plexus or nerve root. This approach is easy and safe for surgical procedures.  相似文献   
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The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.  相似文献   
79.
The purpose of this study was to investigate cellular feasibility in the proliferation and differentiation status of adult chondrocytes for cartilage regeneration in comparison to fetal chondrocytes. Primary cells were isolated from adult (n = 6) and fetal (n = 6) sheep ear cartilages and expanded in 10% fetal bovine serum (FBS) containing Ham's F12 medium, in which adult and fetal cell proliferation rates were compared using a WST-1 assay kit. Approximately 4 million cells were seeded onto each 1 x 1 x 0.2-cm (200 microL) nonwoven fabric scaffold made from polyglycolic acid. Cell/polymer constructs were cultured in serum-free DMEM/F12 medium supplemented with 5 ng/mL TGF-beta2 and 5 ng/mL des(1-3)IGF-I (adult chondrocytes, group A) or in 10% FBS containing Ham's F12 medium (adult chondrocytes, group B, and fetal chondrocytes, group C) as controls in a rotating bioreactor for 6 weeks. The proliferation assay showed that fetal cells had a significantly better growth potential than did adult cells. Histology and extracellular matrix analyses revealed that groups A and C qualitatively displayed better matrix deposition than did group B. In conclusion, although adult sheep elastic chondrocytes had less growth potential than did fetal cells, the serum-free medium supplemented with growth factors significantly enhanced the production of cartilage matrix secreted from proliferated adult sheep elastic chondrocytes.  相似文献   
80.
BACKGROUND: To clarify the pathology of the development of prostatic disorders such as inflammation, cancer, and hyperplasia, we compared histopathological findings of the prostate according to age group. METHODS: Whole-mount sections of prostates were used to assess the relationship between age and prostate weight (n=962), prostate histological composition in the transition zone (TZ) and in the peripheral zone (PZ) (n=68), prostate histopathological findings by zone (n=102), and comparison of latent tumor development by age group (n=1,815). RESULTS: A rapid increase in prostate weight from birth to the 20s was followed by a slow rise thereafter. Volume increases (P<0.01) were observed in all components of glandular epithelium, glandular lumen, and stroma in the TZ from the 40s to 70s inclusive. In the PZ, the epithelial and stromal volumes tended to decrease in an age-dependent manner (P<0.05). Calculi and lymphocyte infiltration were detected at a relatively early age, with a tendency towards an age-dependent increase. Glandular dilation and nodular hyperplasia were noted first in the 30s group, also with a tendency towards age-dependent increase. Latent tumors were first detected in the 30s group (5.6%), and slowly increased thereafter. CONCLUSIONS: There was an age-dependent trend towards prostate glandular dilation and prostate enlargement with inflammation. It was demonstrated that tumor and hyperplasia have a long natural history, usually starting in the fourth decade of life, accompanied by dynamic changes with age in glandular tissue composition as well as cell proliferation activity.  相似文献   
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