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61.
OBJECTIVE: The purpose of this study was to describe the computed tomography (CT) and pathologic features of 5 nodules of pulmonary dirofilariasis in 4 patients. METHODS: Four patients with 5 nodules of pathologically confirmed pulmonary dirofilariasis who under went CT were enrolled, and the imaging interpretations were retrospectively compared with the histopathologic characteristics. RESULTS: Three of the 4 patients had a solitary nodule, and the remaining patient had 2 nodules. All the nodules were distributed in the right lower lobe and were attached to the pleura. They were all round or oval in shape and ranged in size from 11 to 22 mm in largest diameter (mean=17 mm). On thinner section CT, the nodules had a well-defined smooth margin with or without a shallow notch; they were connected to the arterial branch and, occasionally, to the venous branch. On contrast-enhanced CT, all the nodules contained a homogeneous low-attenuation area, which corresponded to areas of coagulative necrosis on histopathologic examination. CONCLUSION: Although the CT findings of a pulmonary dirofilariasis nodule are nonspecific, awareness of the findings on contrast-enhanced CT and the pathologic appearance of this rare benign condition may facilitate its differentiation from a malignant nodule.  相似文献   
62.
A case of giant thyroid tumor with tracheal stenosis   总被引:1,自引:0,他引:1  
A 61-year-old female underwent resection of a giant thyroid tumor, and tracheal stenosis ensued. She had cough, dyspnea, and palpitation in the supine position. The giant thyroid tumor was of the size of 11 x 12 cm and the diameter of trachea was 8 x 6 mm at 3.5 cm below the vocal cord, at which point the trachea was the narrowest on cervical computed tomography. The peak expiratory flow rate from the flow-volume curve was 2.94 l x sec(-1) (% predicted value 55.2%) in the upright position. We were concerned about difficult airway management. Oro-tracheal intubation with an armored tube (ID 7.5 mm) was performed after intravenous midazolam 2 mg and fentanyl 50 microg, 4% lidocaine spray 2 ml with oxygen 6 l x min(-1) inhalation keeping spontaneous breathing and consciousness. Anesthesia was induced and maintained with intravenous propofol, fentany, vecuronium and nitrous oxide in oxygen to keep the bispectral index between 40 and 60. The extracted thyroid tumor was 620 g in weight. A careful preoperative evaluation of the airway using ultrasonography, CT, MRI, laryngoscopy, bronchoscopy and respiratory function test, especially peak expiratory flow rate of the flow-volume curve is important in such a case of a giant thyroid tumor. Intubation under conscious sedation with midazolam and fentanyl is useful for a patient with a giant thyroid tumor and tracheal stenosis.  相似文献   
63.

Purpose

Creation of a vesico-amniotic shunt for obstructive uropathy removes the normal fetal urination cycle. It is unclear how this affects bladder function at term. The authors measured the bladder volume and reviewed the bladder histology after fetal vesicostomy.

Methods

The authors created an obstructive uropathy in fetal lambs at 60 days’ gestation by ligating the urethra and urachus. Vesicostomy (female) or urethrostomy (male) were performed 21 days after obstruction to release the obstruction. The fetuses were killed at term (145 days).

Results

Thirteen fetuses were shunted. Seven fetuses miscarried after shunting. Six survived, and 3 had a successful shunt with a very small bladder (5 to 7 mL). Two had incomplete shunts that failed some time after shunting. These both had huge bladders (399 mL). In one, the obstruction was unsuccessful. Histologic examination showed that the obstruction caused bladder muscle hypertrophy. Shunted lambs had severe fibrosis of the bladder wall and very poor bladder compliance.

Conclusions

Shunt operations after obstructive uropathy may salvage the kidney but fail to preserve bladder function. The fetus needs a normal urination cycle for normal bladder development. This requirement exists even when the obstruction is successfully bypassed.  相似文献   
64.

Objectives

This study aimed to evaluate the efficacy of radiation therapy for pelvic lymph node metastasis from uterine cervical cancer and identify an optimal radiation regimen.

Methods

A total of 111 metastatic pelvic lymph nodes, ranging from 11 to 56 mm (median, 25 mm) on CT/MRI, in 62 patients with uterine cervical cancer were treated initially with curative radiation therapy, with 46 patients receiving concurrent chemotherapy. Total radiation doses ranged from 45 to 61.2 Gy (median, 50.4 Gy) in 1.8–2 Gy (median, 1.8 Gy) fractions.

Results

At a median follow-up of 33 months, 46 of the 62 patients survived. Only 2 irradiated lymph nodes, 24 and 28 mm in diameter, in 1 patient progressed after irradiation alone with 50.4 Gy in 1.8 Gy fractions. All 33 metastatic lymph nodes ≥ 30 mm in diameter were controlled by irradiation at a median dose of 55.8 Gy. The 3-year lymph node-progression free rates were 98.2% in all 62 patients and 98.0% in all 111 metastatic lymph nodes. Except for transient hematologic reactions, 2 patients developed grade ≥ 3 therapy-related toxicities, 1 with an ulcer and the other with perforation of the sigmoid colon. In addition, 2 patients experienced ileus after irradiation.

Conclusions

Radiation therapy effectively controlled pelvic lymph node metastases in patients with uterine cervical cancer, with most nodes < 24 mm in diameter controlled by total doses of 50.4 Gy in 1.8 Gy fractions and larger nodes controlled by 55.8 Gy, particularly with concurrent chemotherapy. Higher doses to metastatic lymph nodes may increase intestinal toxicities.  相似文献   
65.
Background Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder for which appropriate diagnostic treatments are uncertain. The response to splenectomy varies from 60% to 90%, and the remaining patients relapse and require further treatment. Therefore, it is important to predict the outcome of splenectomy before and after surgery. The objective of this study was to evaluate the efficacy of splenectomy in patients diagnosed with ITP. Materials and Methods From 1988 to 2004, we splenectomized 32 patients with ITP; 17 underwent laparoscopic splenectomy (LS) and 15 underwent conventional open splenectomy (OS). For analysis, patients were separated retrospectively into two groups: the “responding group,” those who showed good outcomes with splenectomy, and the “non-responding group,” those who did not show good outcomes with splenectomy. Blood samples were examined before and immediately after surgery (day 0) and on postoperative days (POD) 1, 3, 5, and 7. Results The median follow-up was 8.3 years (range: 1–16 years). The overall 5- and 10-year survival rates after splenectomy were 96.9% (one death). The responding group included 24 patients (75%), and the non-responding group included 7 (21.9%). Platelet counts in the responding group increased gradually until POD 7, and although platelet counts in the non-responding group were almost constant until POD 5, they subsequently decreased until POD 7. Average platelet counts in the responding and non-responding groups were 269 and 124 × 109/l on POD 7, respectively (P < 0.05). The pre- to post-surgery ratio of platelet counts were almost the same as the result of the actual data. Platelet counts during the long-term follow-up for the responding and non-responding groups were related to those noted on discharge. Conclusions A high platelet count on POD 7 was associated with a good response to splenectomy, but age at surgery, the time interval between diagnosis and splenectomy, and prior responses to corticosteroid were not. We suggest that long-term outcomes of splenectomy can easily be predicted by platelet counts on POD 7.  相似文献   
66.
A 15-year-old boy presented with a history of medically refractory gelastic seizures and cognitive impairments. Neuroimaging demonstrated a sessile type hypothalamic hamartoma, which was treated by gamma knife surgery. However, the gelastic seizures only partially decreased and the frequency of seizures remained unchanged. One year later, angiography before surgery detected anterior paraclinoid aneurysm of the left internal carotid artery. Blood pressure and endocrinological examinations showed no abnormality. Direct surgery was performed to treat the aneurysm and hamartoma. No sclerotic changes were noted in the arterial wall. The aneurysm was treated with clipping, and the hamartoma was partially removed. Postoperative course was uneventful and the gelastic seizures disappeared. No evidence for a causal relationship between the hamartoma and aneurysm was found.  相似文献   
67.
Annals of Nuclear Medicine - A new tau PET tracer [18F]MK-6240 has been developed; however, its dosimetry and pharmacokinetics have been published only for a European population. This study...  相似文献   
68.

Purpose

The intra-operative femorotibial joint gap and ligament balance, the predictors affecting these gaps and their balances, as well as the postoperative knee flexion, were examined. These factors were assessed radiographically after a posterior cruciate-retaining total knee arthroplasty (TKA). The posterior condylar offset and posterior tibial slope have been reported as the most important intra-operative factors affecting cruciate-retaining-type TKAs. The joint gap and balance have not been investigated in assessments of the posterior condylar offset and the posterior tibial slope.

Methods

The femorotibial gap and medial/lateral ligament balance were measured with an offset-type tensor. The femorotibial gaps were measured at 0°, 45°, 90° and 135° of knee flexion, and various gap changes were calculated at 0°–90° and 0°–135°. Cruciate-retaining-type arthroplasties were performed in 98 knees with varus osteoarthritis.

Results

The 0°–90° femorotibial gap change was strongly affected by the posterior condylar offset value (postoperative posterior condylar offset subtracted by the preoperative posterior condylar offset). The 0°–135° femorotibial gap change was significantly correlated with the posterior tibial slope and the 135° medial/lateral ligament balance. The postoperative flexion angle was positively correlated with the preoperative flexion angle, γ angle and the posterior tibial slope. Multiple-regression analysis demonstrated that the preoperative flexion angle, γ angle, posterior tibial slope and 90° medial/lateral ligament balance were significant independent factors for the postoperative knee flexion angle. The flexion angle change (postoperative flexion angle subtracted by the preoperative flexion angle) was also strongly correlated with the preoperative flexion angle, posterior tibial slope and 90° medial/lateral ligament balance.

Conclusion

The postoperative flexion angle is affected by multiple factors, especially in cruciate-retaining-type TKAs. However, it is important to pay attention not only to the posterior tibial slope, but also to the flexion medial/lateral ligament balance during surgery. A cruciate-retaining-type TKA has the potential to achieve both stability and a wide range of motion and to improve the patients’ activities of daily living.  相似文献   
69.
In recent years, a large number of tryptamine-based designer drugs have been encountered in forensic samples. We have developed simultaneous analytical methods for 14 tryptamine analogues using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS). Trimethylsilyl (TMS) derivatives of the analytes were separated on a DB-1ms column within 15 min. The structural isomers could be differentiated by electron ionization GC–MS. LC–MS–MS with a C18 column could separate structural isomers of tryptamines except for a combination of 5-methoxy-N,N-diethyltryptamine and 5-methoxy-N-methyl-N-isopropyltryptamine. Higher collision energy gave different product ion spectra between the structural isomers. The results indicate that GC–MS is the first choice for identification of tryptamines, preferably after TMS derivatization, and LC–MS–MS can be used as a complementary approach for the unequivocal differentiation of tryptamine isomers.  相似文献   
70.
In recent years, a large number of clandestinely produced controlled-substance analogs (designer drugs) of amphetamine with high structural variety have been detected in forensic samples. Analytical differentiation of regioisomers is a significant issue in forensic drug analysis because, in most cases, legal controls are placed only on one or two of the three isomers. In this study, we used gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the differentiation of regioisomers of fluoroamphetamine analogs (fluoroamphetamines and fluoromethamphetamines), which were synthesized in our laboratories. Free bases and their acylated and silylated derivatives were subjected to GC–MS analysis using DB-1ms, DB-5ms, and DB-17ms capillary columns. The separation of free bases was incomplete on all columns. Trifluoroacetyl derivatives of 3- and 4-positional isomers showed slight separation on DB-1ms and DB-5ms. On the other hand, trimethylsilyl derivatization enabled baseline separation of six fluoroamphetamine analogs on DB-1ms and DB-5ms columns, which was sufficient for unequivocal identification. For LC–MS/MS, a pentafluorophenyl column was able to separate six regioisomeric fluoroamphetamine analogs but a conventional C18 column could not achieve separation between 3- and 4-positional isomers. These results show that a suitable choice of derivatization and analytical columns allows the differentiation of regioisomeric fluoroamphetamine analogs.  相似文献   
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