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21.
Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery. 相似文献
22.
Shambhu K Sah Ying Li Yongmei Li 《International journal of clinical and experimental pathology》2015,8(9):11785-11791
Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UCPOGC) is an extremely rare non-endocrine pancreatic tumor. To date, some cases have been reported, however, histogenesis and biologic behavior of UCPOGC remain controversial. We report a case of an UCPOGC in a 54-year-old female, who presented with a three-month history of recurrent abdominal pain without any incentive. Abdominal computed tomography (CT) revealed a large cystic mass of 10.5 × 9.3 cm in the body and tail of the pancreas compressing the adjacent bowel loop and stomach. The preliminary diagnosis was considered as a malignant tumor of body and tail of the pancreas. The patient had open distal pancreatic mass resection with splenectomy and according to the results of histopathological and immunohistochemical studies, the diagnosis of an UCPOGC was established. 相似文献
23.
Dem?r H Aydo?an B Sah?n H Ocal P Ilvan S 《The Turkish journal of gastroenterology》2012,23(4):406-409
Pure, benign epidermoid cysts of the abdominal viscera are rare. There have been only six reports of epidermoid cysts of the cecum in the literature. A 31-year-old female with a previous cesarean delivery was admitted to our hospital with inguinal pain. After admission to the hospital, she was operated with the initial diagnosis of adnexal mass. During the operation, no adnexal pathology was identified. A heterogeneous mass originated from the posterior surface of the cecum was observed. It had no connection with the lumen. The mass was then removed with dissection. Macroscopically, the mass was 9x7 cm in diameter and wall thickness was 0.1 cm. The inner and outer surfaces were smooth. It was filled with a dense yellow, thick-fatty material with no tooth, hair, bone, or calcification areas. On microscopic examination, the inner lining was composed of mature keratinized stratified squamous epithelium with a granular layer. In view of the later findings, the case was reported as epidermoid cyst of the cecum. Although epidermoid cysts are rarely seen in visceral organs, this case is the seventh case of cecum-originated epidermoid cyst that has been reported in the literature. The histogenesis of epidermoid cyst is unknown. These cysts are generally accepted to be sequestration cysts that may be either congenital or acquired. Acquired epidermoid cysts are believed to be traumatic or iatrogenic. The cesarean delivery may have been a cause of this condition in the present case. On ultrasonographic examination, these cysts can be misdiagnosed as ovarian cysts. 相似文献
24.
G. M. Salzmann B. Sah N. P. Südkamp P. Niemeyer 《Archives of orthopaedic and trauma surgery》2013,133(3):303-310
Study design
Case series: Level of evidence, 4.Background
Arthroscopic microfracture of chondral defects across the knee joint is a frequent treatment modality. There is only limited information on the clinical outcome in patients without previous surgery and single lesions.Purpose
Evaluation of clinical outcome following microfracture in patients without previous surgery and single lesions and identification of prognostic factors.Methods
Inclusion criteria were patients with single-lesion knee joint first-line microfracturing at minimum 2 years postoperatively. Charts were reviewed to identify patient and defect characteristics. Clinical outcome was evaluated by IKDC and Lysholm knee scores, Tegner activity scale and a numeric analogue scale (NAS) for function and pain (10 = highest possible function, no pain).Results
Totally, 145 patients (age at operation 47.92 ± 15.7) met inclusion criteria. Average defect size was 2.7 ± 1.9 cm2. Postoperatively, IKDC was 73.1 ± 18.5, Lysholm 77.6 ± 19.1, Tegner 4.5 ± 1.7, NAS pain 6.5 ± 2.6 and NAS function 6.4 ± 2.3. Significantly better clinical outcome was observed in male patients than in female patients. Regression analysis including all patient and defect characteristics highlighted that singly the parameter shorter symptom duration (P = 0.018) significantly predicted an improved postoperative clinical outcome.Conclusion
Microfracturing results in a satisfying clinical outcome, but no full recovery in patients without previous surgery and single lesions. Specific parameters facilitate outcome prognosis and therefore may aid in indicating surgery. 相似文献25.
Rapid prenatal diagnosis of beta thalassemia using DNA amplification and nonradioactive probes 总被引:3,自引:0,他引:3
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common. 相似文献
26.
Biomechanics of cartilage articulation: effects of lubrication and degeneration on shear deformation
OBJECTIVE: To characterize cartilage shear strain during articulation, and the effects of lubrication and degeneration. METHODS: Human osteochondral cores from lateral femoral condyles, characterized as normal or mildly degenerated based on surface structure, were selected. Under video microscopy, pairs of osteochondral blocks from each core were apposed, compressed 15%, and subjected to relative lateral motion with synovial fluid (SF) or phosphate buffered saline (PBS) as lubricant. When cartilage surfaces began to slide steadily, shear strain (Exz) and modulus (G) overall in the full tissue thickness and also as a function of depth from the surface were determined. RESULTS: In normal tissue with SF as lubricant, Exz was highest (0.056) near the articular surface and diminished monotonically with depth, with an overall average Exz of 0.028. In degenerated cartilage with SF as lubricant, Exz near the surface (0.28) was 5-fold that of normal cartilage and localized there, with an overall E(xz) of 0.041. With PBS as lubricant, Exz values near the articular surface were approximately 50% higher than those observed with SF, and overall Exz was 0.045 and 0.062 in normal and degenerated tissue, respectively. Near the articular surface, G was lower with degeneration (0.06 MPa, versus 0.18 MPa in normal cartilage). In both normal and degenerated cartilage, G increased with tissue depth to 3-4 MPa, with an overall G of 0.26-0.32 MPa. CONCLUSION: During articulation, peak cartilage shear is highest near the articular surface and decreases markedly with depth. With degeneration and diminished lubrication, the markedly increased cartilage shear near the articular surface may contribute to progressive cartilage deterioration and osteoarthritis. 相似文献
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29.
Kevin T. Love Kerry P. Mahon Christopher G. Levins Kathryn A. Whitehead William Querbes J. Robert Dorkin June Qin William Cantley Liu Liang Qin Timothy Racie Maria Frank-Kamenetsky Ka Ning Yip Rene Alvarez Dinah W. Y. Sah Antonin de Fougerolles Kevin Fitzgerald Victor Koteliansky Akin Akinc Robert Langer Daniel G. Anderson 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(5):1864-1869
Significant effort has been applied to discover and develop vehicles which can guide small interfering RNAs (siRNA) through the many barriers guarding the interior of target cells. While studies have demonstrated the potential of gene silencing in vivo, improvements in delivery efficacy are required to fulfill the broadest potential of RNA interference therapeutics. Through the combinatorial synthesis and screening of a different class of materials, a formulation has been identified that enables siRNA-directed liver gene silencing in mice at doses below 0.01 mg/kg. This formulation was also shown to specifically inhibit expression of five hepatic genes simultaneously, after a single injection. The potential of this formulation was further validated in nonhuman primates, where high levels of knockdown of the clinically relevant gene transthyretin was observed at doses as low as 0.03 mg/kg. To our knowledge, this formulation facilitates gene silencing at orders-of-magnitude lower doses than required by any previously described siRNA liver delivery system. 相似文献
30.
SP Walker M Permezel SF Berkovic 《BJOG : an international journal of obstetrics and gynaecology》2009,116(6):758-767
While most women with epilepsy can expect a normal pregnancy outcome, epilepsy remains a significant contributor to both maternal and perinatal morbidity. Pre-pregnancy planning must address reliable contraception and optimisation of antiepileptic drug (AED) regimens to minimise teratogenic risk while maintaining seizure control. The most recent data from the AED registries regarding malformations is presented in this review, as is the limited data on the newer AEDs and studies linking neurocognitive outcomes to AED exposure. During pregnancy, important considerations include; therapeutic drug monitoring, surveillance for obstetric complications and vigilance for seizures during the intrapartum and postpartum period. 相似文献