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991.
Carcinogen-induced hepatoma in immunocompetent animal models has shown a progress similar to the clinical course of human hepatoma. Ultrasonography (US) was used for consecutive evaluation of the phenotypic changes in Sprague-Dawley rats exposed for 8 weeks to N-nitrosomorpholine (NNM, 200 mg/L). Three distinctive US findings were ascites, coarseness (defined as small and heterogeneously widespread increased echogenecity), and nodularity (defined as a >0.6-cm-sized echogenic region and clearly showing a tumor-like mass). Abdominal ascites was observed in 5 of 26 rats at week 8 NNM posttreatment and the number of rats showing ascites gradually increased. Coarseness (22 of 26 rats) and nodularity (1 of 18) appeared at weeks 8 and 17 NNM posttreatment, respectively. The gross and histological findings indicated that coarseness and nodularity shown in US reflected fibrosis and hepatocellular carcinoma or cholangiofibroma, respectively. The computer-aided quantification of coarseness and nodularity showed that the regression-linked phenotypic instability was present in coarseness but not in nodularity. We conclude that the heterogeneity of preneoplasia in NNM-treated rats might be induced by phenotypic instability rather than random initiating events of preneoplastic lesion.  相似文献   
992.
Roberts-SC phocomelia syndrome (RS) is an autosomal recessive disorder of symmetric limb defects, craniofacial abnormalities, pre- and postnatal growth retardation, and mental retardation. Patients with RS have been reported to have premature separation of heterochromatin of many chromosomes and abnormalities in the cell-division cycle. No case has been reported who had normal intelligence and normal cell division with typical clinical features of the RS. We report a case of a six-year-old male of clinical and radiologic findings of typical RS with normal cell division and normal intelligence.Although he showed growth retardation, his intelligence was normal. Van Den Berg and Francke later reported that 79 out of 100 cases of Roberts syndrome had premature cell separation (PCS). We think that this case may demonstrate severe expression of the Roberts syndrome even though PCS is not exhibited. The limb involvement of this case was symmetrical, and he showed phocomelia of upper limbs, equinus valgus deformity of ankle, aplasia of fibula, and shortness of fifth toes while his hands and feet were normal with 5 rays each. Craniofacial abnormalities of this case were typical; he showed scaphocephaly, mild hypertelorism, mandibular hypoplasia, dysplastic helix of ear, narrowing of external auditory canal, and cleft palate with wide gap.This report supports the theory that normal intelligence can make social-personal adjustment possible even if all of the stigmata of Roberts syndrome is present.  相似文献   
993.
In a randomized controlled trial, we compared the potential benefits of position changes on arterial oxygen pressure in 32 patients with acute respiratory failure, maintained on artificial ventilators, distinguishing prominently as left-sided, right-sided or bilateral lung disease. Our results indicate that randomly alternating supine, left-lateral, right-lateral and prone positions have influence on gas exchange and that improvement of arterial oxygen pressure is associated with various positions. Our results show, therefore, that nursing care of patients on artificial ventilators involving changes in body positions (a simple and noninvasive means of assistance) has important therapeutic consequences and warrants attention in clinical practice.  相似文献   
994.
Yeh YC  Hwang GY  Liu IP  Yang VC 《Atherosclerosis》2002,161(1):95-103
In this study, we used immunoelectron microscopy to investigate the subcellular localization of scavenger receptor class B type I (SR-BI) in the arterial walls of rats. The expression of SR-BI in cultured endothelial and smooth muscle cells of rat aorta after exposure to high-density lipoprotein (HDL) was also investigated by immunofluorescence microscopy and immunoblotting analysis. A peptide containing residues 495-509 from mouse SR-BI (mSR-BI) plus an NH2-terminal cysteine was coupled to hemocyanin to generate mSR-BI antiserum in rabbits. Reactivity of antiserum against the synthetic peptides was confirmed with an enzyme-linked immunosorbent assay (ELISA). The results showed that SR-BI was specifically localized on the surface of the endothelial cells and smooth muscle cells. SR-BI was also observed in the cytoplasm of smooth muscle cells. Immunoblotting analysis indicated that SR-BI was expressed in the cell membrane. The levels of SR-BI increased gradually from 1 to 3 h and decreased at 24 and 48 h after cholesterol-loaded cells were incubated in the culture medium containing HDL. We conclude that SR-BI, a functional receptor for HDL, is expressed in the aortic endothelial cells as well as in smooth muscle cells. This receptor also responds to the presence of HDL in the culture medium.  相似文献   
995.
Lin CL  Lieu AS  Lee KS  Yang YH  Kuo TH  Hung MH  Loh JK  Yen CP  Chang CZ  Howng SL  Hwang SL 《Surgical neurology》2003,60(5):402-6; discussion 406
BACKGROUND: By the use of conditional probabilities of survival, we studied the yearly survival rates for individual tumor survivors. METHODS: Conditional survival rate was estimated in 114 consecutive patients with anaplastic astrocytoma or glioblastoma multiforme. Conditional probabilities of surviving some years given survival to a specific period of time after craniotomy and 95% confidence intervals were calculated in the individual tumor survivors. RESULTS: The estimated median survival was 30 months for 45 patients with anaplastic astrocytoma and 12 months for 69 patients with glioblastoma multiforme. The conditional probabilities of surviving next one year given survival to 1 year, 2 years, 3 years, 4 years, or 5 years after craniotomy for anaplastic astrocytoma were 86.2%, 75.0%, 85.9%, 77.8%, or 85.7%, respectively; for glioblastoma multiforme 64.8%, 58.7%, 85.7%, 80.0%, or 75.0%, respectively. The conditional probability of surviving to 5 years given survival to 2 years after craniotomy for anaplastic astrocytoma, i.e., surviving an additional 3 years, was 50.1%, which was better than observed 5-year survival rate (28.6%); for glioblastoma multiforme it was 40.2%, which also was better than observed 5-year survival rate (12.4%). CONCLUSIONS: The conditional probability of survival was a good method to clinically predict yearly survival rate for individual tumor survivors. In addition, the method can estimate the probabilities of surviving next some years given survival to a specific period of time after craniotomy. It also showed a more encouraging result than observed survival rate in patients with supratentorial malignant astrocytomas.  相似文献   
996.
Gwak HS  Hwang SK  Paek SH  Kim DG  Jung HW 《Surgical neurology》2003,60(1):39-48; discussion 48
BACKGROUND: The authors present a retrospective analysis of 29 consecutive patients with trigeminal neurinomas. Modified classification based on the tumor distribution over petrous ridge is suggested to select the optimal surgical approach and to predict the outcome. METHODS: Preoperative computed tomography (CT) or magnetic resonance (MR) images were analyzed to measure a long diameter of tumor axis (LD), which divided into middle and posterior fossa and a width of the petrous erosion (PW) by the tumor on axial image. The tumors were classified into four groups (M, tumor confined to middle fossa; Mp, tumor mainly in middle fossa; M = P, tumor equally distributed into both middle and posterior fossa; Pm, tumor mainly in cisternal space of posterior fossa with slender, rarely round extension into Meckel's cave), and extent of removal was compared between the groups. Long-term outcomes were based on recurrence-free survival. RESULTS: Total removal was achieved in 16 patients including stage operation (55%). Excluding three tumors, which underwent gamma knife for residual tumor, 8 of 10 subtotally removed tumors recurred at 50 months on average. The LD and PW are significantly different among the tumor types. The M = P type is the largest in both parameter, while the M type is the smallest in LD; Pm type is the smallest in PW, respectively. The tumors with equal or lager posterior fossa component (M = P and Pm type) were more difficult to remove totally by single attempt than those with smaller or nil posterior fossa mass (Mp and M type). Also, the corrected PW (PW over the tumor diameter of minor portion) shows a tendency to influence the extent of removal as the relatively narrow PW hindered the total removal. CONCLUSIONS: Aggressive attempt for total removal using skull base approach is recommended, especially for those having dominant posterior fossa component and for those having relatively narrow PW.  相似文献   
997.
Innervation of calf muscles in relation to calf reduction   总被引:7,自引:0,他引:7  
Plump and muscular calves, a so-called radish-like leg, embarrass young women and cause a feeling of inferiority in Korea. Damage to motor nerves innervating a muscle makes the muscle paralyzed and dystrophic, with loss of muscle volume. The authors studied the morphometry of the motor branches of the tibial nerve innervating the gastrocnemius and soleus muscle and sensory medial sural cutaneous nerve in popliteal fossa. Dissection and exploration of the tibial nerve were performed in the popliteal fossae of 70 legs (of 18 males and 17 females) of embalmed Korean cadavers. The main branch of the tibial nerve innervating medial and lateral gastrocnemius muscle originated 3 cm above and below the popliteal crease. The medial gastrocnemius muscle had an additional nerve (49%). The medial sural cutaneous nerve came off the nerve into the medial gastrocnemius muscle (30%) and diverged 5.5 mm from the tibial nerve. The nerve into the soleus muscle originated from the nerve innervating the lateral gastrocnemius muscle (30%) and was 12.3 mm away from it. Surgeons should keep in mind that the medial sural cutaneous nerve originates from the nerve to medial gastrocnemius in 30% and the nerve to soleus muscle originates from the nerve to lateral gastrocnemius in 30%.  相似文献   
998.
999.
We present a case of an 85-year-old woman with a 40-year history of progressive bilateral sensorineural hearing loss. Imaging studies demonstrated bilateral pseudoaneurysms of the petrous portion of the internal carotid arteries eroding into both cochleas. To our knowledge, this is the first case report of such lesions.  相似文献   
1000.
OBJECT: The reported incidence, timing, and predictive factors of perioperative seizures and epilepsy after subarachnoid hemorrhage (SAH) have differed considerably because of a lack of uniform definitions and variable follow-up periods. In this study the authors evaluate the incidence, temporal course, and predictive factors of perioperative seizures and epilepsy during long-term follow up of patients with SAH who underwent surgical treatment. METHODS: Two hundred seventeen patients who survived more than 2 years after surgery for ruptured intracranial aneurysms were enrolled and retrospectively studied. Episodes were categorized into onset seizures (< or = 12 hours of initial hemorrhage), preoperative seizures, postoperative seizures, and late epilepsy, according to their timing. The mean follow-up time was 78.7 months (range 24-157 months). Forty-six patients (21.2%) had at least one seizure post-SAH. Seventeen patients (7.8%) had onset seizures, five (2.3%) had preoperative seizures, four (1.8%) had postoperative seizures, 21 (9.7%) had at least one seizure episode after the 1st week postoperatively, and late epilepsy developed in 15 (6.9%). One (3.8%) of 26 patients with perioperative seizures (onset, preoperative, or postoperative seizure) had late epilepsy at follow up. The mean latency between the operation and the onset of late epilepsy was 8.3 months (range 0.3-19 months). Younger age (< 40 years old), loss of consciousness of more than 1 hour at ictus, and Fisher Grade 3 or greater on computerized tomography scans proved to be significantly related to onset seizures. Onset seizure was also a significant predictor of persistent neurological deficits (Glasgow Outcome Scale Scores 2-4) at follow up. Factors associated with the development of late epilepsy were loss of consciousness of more than 1 hour at ictus and persistent postoperative neurological deficit. CONCLUSIONS: Although up to one fifth of patients experienced seizure(s) after SAH, more than half had seizure(s) during the perioperative period. The frequency of late epilepsy in patients with perioperative seizures (7.8%) was not significantly higher than those without such seizures (6.8%). Perioperative seizures did not recur frequently and were not a significant predictor for late epilepsy.  相似文献   
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