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81.
Three infants with anterior abdominal wall defects (gastroschisis and exomphalos) who presented with obstructive jaundice secondary to biliary obstruction, are described. All three infants had abnormal biliary systems, with mechanical distortion of the biliary tree. Biliary obstruction secondary to structural biliary anomalies should be considered in patients with abdominal wall defects and cholestasis, as prolonged unrelieved biliary obstruction may lead to biliary cirrhosis and portal hypertension.  相似文献   
82.
OBJECTIVE: Cochlear implants (CIs) attempt to mimic the tonotopicity of the normal ear by stimulating more basal regions of the cochlea in response to higher frequencies. However, there may be a mismatch between the normal place-frequency map and that implemented by a CI. MATERIAL AND METHODS: Aiming to measure this potential mismatch and its changes over time, the present study used a method-of-adjustment procedure where CI users and normal-hearing listeners selected synthetic vowels to match prespecified vowel targets. Data from CI users were obtained longitudinally, starting on the day of initial stimulation and continuing for 2 years. RESULTS: CI users showed a significant amount of initial mismatch with respect to the normal-hearing listeners, but they also showed significant learning and adaptation over time and achieved nearly normal performance after some experience with the CI. CONCLUSION: In general, the adaptation process took several months, suggesting that some CI users may benefit from alternative signal processing or rehabilitation procedures designed to facilitate perceptual learning after cochlear implantation.  相似文献   
83.
INTRODUCTION: The occurrence of thrombocytopenia in the perioperative period after a liver transplant is not uncommon. However, there are few studies on persistent thrombocytopenia during the longer follow up period of patients after liver transplantation. We examined the prevalence of and contributing factors to persistent thrombocytopenia beyond 1 year post-liver transplantation. METHODS: We analyzed adult patients followed for at least 1 year posttransplant with full blood counts and abdominal scans, as well as clinical notes. RESULTS: The 35 patients of mean age at transplant of 50 years and showed a mean follow-up of about 4 years showed a prevalence of persistent thrombocytopenia at 12 months of 54% and at 3 years of 25%. Factors that were associated with persistent thrombocytopenia were pretransplant variceal bleeding, splenomegaly, and thrombocytopenia at 3 and 6 months posttransplant. After multivariate analysis only the latter represented independent factors for persistent thrombocytopenia at 1 and 3 years posttransplant, respectively. CONCLUSION: Persistent thrombocytopenia improved over time posttransplant; no bleeding problem was observed among the affected cases.  相似文献   
84.
INTRODUCTION: One of the major concerns in liver transplant patients who survive past 1 year posttransplant is the development of chronic diseases. AIM: We studied two important clinical conditions that can have a chronic course-renal impairment and diabetes mellitus-among long-term liver transplant survivors. METHODS: All adult patients transplanted and followed for at least 1 year were evaluated for clinical status, blood tests, and imaging studies. The occurrence and development of renal impairment, defined as a serum creatinine above 125 micromol/L or creatinine clearance less than 75 mL/min, or diabetes mellitus were evaluated for contributing factors. RESULTS: The 35 evaluated patients of mean age at transplant of 50 years had a mean follow-up duration of 45 months. The incidence of posttransplant renal impairment was 22.8% at 1 year and 47.6% at 3 years. This disorder was associated with pretransplant renal impairment and with a diagnosis of diabetes. Posttransplant diabetes mellitus was observed in 48.6% with 41.1% resolving over time. CONCLUSION: Posttransplant renal impairment appears to be a potential long-term problem. Although this relates to pretransplant conditions, longer follow-up is required to examine whether posttransplant factors contribute to its progression.  相似文献   
85.
OBJECTIVE: We tested the hypothesis that multiple pregnancies would be associated with altered expression of the following three groups of proteins that are key regulators of myometrial function: (i) Gsalpha, (ii) connexins-43 and 26, and (iii) prostanoid EP1, EP3, and EP4 receptors. METHODS: An in vitro model was used to determine the effects of mechanical stretch on myometrial cell Gsalpha expression. Then the effects of the steroid hormones beta-estradiol and progesterone were tested on Gsalpha expression in vitro. All in vitro studies were performed using myometrium from nonlaboring women. RESULTS: There were no differences in the expression of Gsalpha, prostaglandin E2 receptors, or gap junction proteins in myometrium of singleton versus multiple pregnancies. Mechanical stretch did not alter Gsalpha expression in vitro, and Gsalpha expression was unaffected by steroid hormones. CONCLUSION: These results suggest that the methods whereby stretch can promote myometrial contraction are complex or require additional factors than those tested here. Alternatively, cases of multiple gestation that do not result in preterm labor perhaps compensate for the increased stretch by preventing aberrant expression of the proteins investigated in this study.  相似文献   
86.
After anterior subfascial transposition, the ulnar nerve lies superficial to the flexor-pronator muscle group but deep to its fascia. Eight patients with cubital tunnel syndrome were treated with this method and reviewed retrospectively. The average age at the time of operation was 52 years. All patients had severe cubital tunnel syndrome based on Dellon's classification. The average follow-up period was 2 years and 9 months. Post-operative outcome assessment was based on the modified Bishop rating system. Six patients had excellent and two had good outcomes. All were back at work by the 5th post-operative week. There were no complications or recurrence of symptoms. Anterior subfascial transposition of the ulnar nerve is an effective method of surgical treatment for patients with severe cubital tunnel syndrome.  相似文献   
87.
We investigated the effect of sequential administration of intrathecal (IT) hyperbaric bupivacaine (after the initial administration of IT hypobaric fentanyl) on the duration of spinal analgesia. Thirty-seven nulliparous parturients with a cervical dilation >/= 5 cm were randomized to receive either IT fentanyl 25 micro g and plain bupivacaine 2.5 mg (group P; n = 19) or IT fentanyl 25 micro g and hyperbaric (with 8% glucose) bupivacaine 2.5 mg (group H; n = 18). The two components of the IT injectate were administered sequentially (fentanyl 25 micro g diluted in 2 mL of normal saline, immediately followed by 0.5 mL of 0.5% bupivacaine). Patients were then positioned with their torso elevated at 30 degrees for 30 min. Pain scores using 0-100 visual analog scales were collected before combined spinal/epidural analgesia and at 5, 15, and 30 min after the block. Patients in Group H had a longer median duration of analgesia (122 min; range, 80-210 min) than Group P (95 min; range, 75-125 min) (P < 0.01). Group H also had a more limited dermatomal spread (median highest sensory level of T8 versus T4 in group P; P < 0.05). The side-effect profile was similar. Under these circumstances, hyperbaric bupivacaine conferred an increased duration of IT analgesia compared with plain bupivacaine.  相似文献   
88.
89.
We report a case of Bizarre Parosteal Osteochondromatous Proliferation (BPOP) of the hand that was initially misdiagnosed as an osteochondroma. BPOP, although a benign lesion, behaves aggressively with rapid growth and high risk of local recurrence after local resection. The distinguishing features of BPOP as opposed to an osteochondroma are discussed.  相似文献   
90.
This is a case report of recurrent bilateral ovarian cysts in pregnancy. From the clinical picture these are likely to be theca lutein cysts. A lookout for complications involving these cysts is important. Patients can be managed conservatively in the absence of complications. Likely mechanisms for the causation of this phenomenon are discussed.  相似文献   
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