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11.
Hyo-Chang Kim Seok-Gu Kang Pil-Woo Huh Do Sung Yoo Kyoung Suok Cho Dal Soo Kim 《Journal of clinical neuroscience》2007,14(11):1135-1139
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition. 相似文献
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Airway hyperresponsiveness (AHR) is a characteristic feature of asthma, but is also frequently demonstrated by children and adults with chronic obstructive lung diseases. AHR is usually measured by bronchial challenges using direct or indirect stimuli. The aim of this study was to compare these two types of bronchial challenge in children with post-infectious bronchiolitis obliterans (BO). Methacholine and adenosine 5'-monophosphate (AMP) challenges were used as tools for the evaluation of AHR to direct and indirect stimuli, respectively, in children with post-infectious BO (n = 28). These results were compared with those of asthmatic (n = 30) and control children (n = 25). Altogether, twenty-two patients (78.6%) with post-infectious BO were hyperreactive to methacholine with a provocative concentration causing a 20% fall in forced expiratory volume in one second (PC20) of <16 mg x mL(-1), but only six (21.4%) were hyperreactive to AMP with a PC20 of <200 mg x mL(-1). All patients with asthma responded positively to methacholine, and most (28, 93.3%) also responded positively to AMP. The majority of controls were insensitive to both challenges. Airway hyperresponsiveness to methacholine is a frequent, but by no means universal, finding in children with post-infectious bronchiolitis obliterans, but is usually not accompanied by airway hyperresponsiveness to adenosine 5'-monophosphate. This finding suggests that airway hyperresponsiveness in patients with post-infectious bronchiolitis obliterans has characteristics that differ from those of asthmatic subjects. 相似文献
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To elucidate the mechanisms by which thiamine deficiency affects hepatic microsomal monooxygenase activities, the effect of thiamine deficiency on two constitutive cytochrome P450 isozymes, P450IIE1 and P450IIC11, was investigated, using weanling male Sprague-Dawley rats. The clinical signs of thiamine deficiency were apparent after feeding a thiamine-deficient diet for 3 weeks. Thiamine deficiency caused an increase in P450IIE1, which was determined by N-nitrosodimethylamine demethylase assay and immunoquantitation of P450IIE1. This increase in the P450IIE1 level was mainly attributed to thiamine deficiency per se but not to dietary restriction. Ketone bodies were not elevated in thiamine-deficient rats, whereas ketone bodies were elevated and may have served as inducing factors in calorically restricted pair-fed animals. Injections of pyruvate or pyrithiamine in addition to thiamine deficiency did not potentiate the induction effect. On the other hand, thiamine deficiency did not affect the level of P450IIC11 during the 3 weeks of feeding the thiamine-deficient diet. In addition, thiamine deficiency increased cytosolic glutathione S-transferase activity but not steroid isomerase activity. The present study demonstrates the specificity of thiamine deficiency per se in the induction of P450IIE1 which does not involve an increase in the ketone body level. 相似文献
17.
Ischemic necrosis of the entire femoral head and rapidly destructive hip disease: potential causative relationship 总被引:6,自引:0,他引:6
Kyung Nam Ryu Eui Jong Kim Myung Chul Yoo Yong Koo Park David J. Sartoris Donald Resnick 《Skeletal radiology》1997,26(3):143-149
Objective. Rapidly destructive hip disease (RDHD) is an uncommon disorder of the hip that has been considered a disease of unknown cause
and distinct from ischemic necrosis of the femoral head. The objective of this study was to investigate ischemic necrosis
of the femoral head as one potential cause of RDHD. Design and patients. In 600 patients who underwent MR imaging of the hip, 20 cases of ischemic necrosis involving the entire femoral head in 18
patients (3%) were retrospectively studied with routine radiography and MR imaging. All patients had surgically confirmed
ischemic necrosis of the femoral head. Results and conclusions. All patients showed rapid destruction of the femoral head on routine radiography and MR imaging as compared with the gradual
onset of clinical symptoms. Plain radiographs showed several bone fragments at the inferomedial aspect of the femoral head
(75%), acetabular erosions (55%), eccentric depression at the lateral articular surface of the femoral head conforming to
the adjacent acetabulum (35%), and mild osteoarthritis (15%). Bone sclerosis was often present at sites of impaction between
the femoral head and the acetabulum. MR imaging showed marked distention of the joint capsule in all cases. In 14 of 20 cases,
the contents of the joint space showed predominantly low or intermediate signal intensity on T1- and T2-weighted images. Ischemic
necrosis involving the entire femoral head may represent one of the causes of RDHD. 相似文献
18.
Arthroscopic all-inside repair techniques of lateral meniscus anterior horn tear: a technical note 总被引:1,自引:0,他引:1
Choon Key Lee Jeung Tak Suh Chong Il Yoo Hyung Lae Cho 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1335-1339
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus,
it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule.
Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal
tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair
using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical
mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these
techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus. 相似文献
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Doxorubicin-conjugated biodegradable polymeric micelles having acid-cleavable linkages. 总被引:13,自引:0,他引:13
Doxorubicin was chemically conjugated to the terminal end of a di-block copolymer composed of poly(L-lactic acid) (PLLA) and methoxy-poly(ethylene glycol) (mPEG) via two acid-cleavable linkages. A hydrazone bond and a cis-acotinyl bond were formed between doxorubicin and the terminal group of PLLA segment in the block copolymer. Doxorubicin-conjugated PLLA-mPEG di-block copolymers self-assembled to form micelles in aqueous solution. The doxorubicin-conjugated micelles were about 89.1 nm in diameter and their critical micelle concentration was 1.3 microg/ml. These values were comparable with those of unconjugated micelles. In an acidic condition, the conjugated doxorubicin in the hydrazone linkage was readily cleaved, releasing doxorubicin in an intact structure. Doxorubicin-conjugated PLLA-mPEG micelles were more potent in cell cytotoxicity than free doxorubicin, suggesting that they were more easily taken up within cells with concomitant rapid release of cleaved doxorubicin into the cytoplasm from acidic endosomes. 相似文献