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51.
A standard Glenn anastomosis between the superior vena cava and the right pulmonary artery has been the accepted mode of treatment for patients with complex cyanotic congenital heart disease. We report our experience in 18 patients with such disease who underwent a bidirectional cavopulmonary shunt because of increasing cyanosis and growth cessation. All patients were considered less than "ideal" candidates for a Fontan procedure. We divided the patients into two groups: group 1 had azygos continuation and group 2 did not. Fourteen patients required hypothermic cardiopulmonary bypass. Bidirectional pulmonary blood flow was achieved in all patients. Only 1 death occurred (group 2). The improvement in oxygen saturation and overall clinical condition of these patients, together with the low mortality and morbidity, is encouraging. However, long-term follow-up is mandatory for a comprehensive evaluation of this surgical approach as definitive palliation or as a first stage for a Fontan operation.  相似文献   
52.
Summary Up-to-date unsatisfactory results obtained in multimodality treatments of malignant glioma have prompted the research of new therapeutic modalities with unconventional modes of action. Lonidamine (LND) is a drug which reduces aerobic glycolytic activity in both human and experimental tumors. This effect mainly depends on the inhibition of mitochondrially-bound hexokinase (HK) which is present in large amounts in malignant cells. A Phase II study was conducted on patients with recurrent glioma; 12 patients were admitted to the study. Clinical side effects were moderate, necessitating a reduction of the dosage in only 1 case. The objective results were evaluated according to the indications of Levin. 2 responders and 3 cases of stable disease were observed out of 10 evaluable patients. The potential value of this new drug is discussed.  相似文献   
53.
The susceptibility to Aspiculuris tetraptera of European Mus musculus hybrids is thought to reflect the disruption of genomic co-adaptation through recombination of the parental genomes. Here, we compared the susceptibility to this parasite between parents and experimental hybrids (intersubspecific until F4, intrasubspecific F1, F2) to clarify the contributions of heterosis and subspecies incompatibility. F1 showed hybrid vigor. Unlike intrasubspecific F2, intersubspecific F2 were less resistant than F1, but revealed no increased susceptibility relative to the parents. Intersubspecific F3 and F4 showed the same hybrid vigor as F1. Heterosis contributed most to the resistance, but the differences between intra- and intersubspecific F2 suggested genomic incompatibilities between subspecies. However, the susceptibility did not increase through the recombination process, showing that disruption of co-adaptation does not directly affect resistance. Even if previous studies still support the selective role of parasites in the current hybrid zone, an alternative hypothesis on the origin of hybrid susceptibility is warranted.  相似文献   
54.
Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.  相似文献   
55.
We present two cases of a thrombus in the ascending aorta causing an acute myocardial infarction (AMI) and review the 10 other cases previously reported in the literature. This life-threatening condition appears to be more common in female smokers in their fifth decade. Suspicion should be raised in individuals at low risk for atherosclerotic disease with coronary angiographic findings not in keeping with the clinical presentation. The diagnosis may be obtained by transesophageal echocardiography, and we generally recommend surgical thrombectomy.  相似文献   
56.
Four affected siblings in a Costa Rican family presented an aggressive polyneuropathy with widespread involvement of many visceral organs and onset during the third decade of life with rapid loss of muscle mass in the lower limbs and severe dysautonomy. The medical histories include vitreous opacity, cardiac enlargement, dermal and gastrointestinal infiltration, and autonomic dysfunction including circulatory compromise and gastrointestinal disturbances. Histological studies using Congo red stain and immunohistochemical assays with antibodies against the transthyretin (TTR) protein showed widespread deposition of amyloid in extracellular areas, including dermis and gastrointestinal lamina propia, endo- and perineural spaces, and vascular walls. A mutation search in the transthyretin (ttr) gene was performed seeking the cause of this severe form of familial amyloidotic polyneuropathy (FAP). We applied single-stranded conformational polymorphism (SSCP)-analyses followed by sequencing of the four exons of the ttr gene, revealing a point mutation in exon 3, a G to A transition that causes a Glu54Lys codon change. Western blots of plasma proteins incubated with anti-transthyretin antibodies after gel electrophoresis provided separation of wild-type and mutant TTR protein in affected family members.  相似文献   
57.
Objectives: To evaluate and to compare the bleeding patterns obtained with two regimens of hormone replacement therapy given to early postmenopausal women with asymptomatic uterine leiomyomas. Methods: In this randomised prospective 1-year study 50 early postmenopausal women with one to four asymptomatic uterine leiomyomas were enrolled into two study-groups to take two regimens of hormone replacement therapy for 12 28-day cycles: (A) Tibolone, 2.5 mg/day; (B) conjugated equine estrogens (CEE), 0.625 mg/day plus medroxyprogesterone acetate (MPA), 5 mg/day. The bleeding patterns and the changes in uterine volume of the 47 outpatients who completed the study were evaluated and compared. Results: Amenorrhea incidence was higher in group A (75.0% of the cycles) than in group B (65.6% of the cycles), while irregular bleeding and irregular spotting incidences were higher in group B (29.7 and 4.7% of the cycles, respectively) compared to group A (22.6 and 2.4% of the cycles, respectively). The mean bleeding and spotting lengths were not statistically different between patients in group A and those in group B. Finally, at the end of the study period transvaginal ultrasonography showed no significant change in leiomyoma size. Conclusions: The results demonstrate that, in early postmenopausal patients with asymptomatic uterine leiomyomas, Tibolone treatment seems to be preferable compared to CEE–MPA continuous combined treatment in relation to the lesser occurrence of irregular bleeding. Furthermore, neither Tibolone nor CEE–MPA therapy, at the doses used here, promote fibroid growth.  相似文献   
58.
59.
A case of somatostatin-producing pancreatic tumor associated with severe insulindependent diabetes mellitus and ketoacidotic coma is reported. The tumor, a 10-cm expansile mass arising from the pancreatic tail of a 70-yr-old woman, was first detected by ultrasonography, performed because of abdominal pain, and subsequently confirmed by computed tomography and fine-needle tumor aspiration. Pathologic investigation showed a predominatly solid-trabecular structure with scattered microacini and psammomatous bodies. A large proportion of tumor cells expressed somatostatin and/or calcitonin. Following resection of the primary tumor and three peripancreatic lymph nodes with metastases, the patient recovered rapidly from her diabetic syndrome and remained in substantially good health during a subsequent 8-yr follow-up period, without evidence of tumor recurrence.  相似文献   
60.
Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society. PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z  相似文献   
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