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71.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
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Chiropractic practitioners with accredited qualifications should have the right to diagnose, the right to operate diagnostic imaging machines, and the right to the title doctor and Yee San. This paper reviews chiropractic practice in Hong Kong as well as laws and provisions of the health professions namely Chiropractors Registration Ordinance, Medical Registration Ordinance, Dentists Registration Ordinance, Radiation Ordinance, and the provisions of codes of practice of Medical Laboratory Technologists and Radiographers. The need for amendments of relevant sections of health laws and provisions, which concern chiropractic rights, chiropractic practice, and clinical research of mechanical neuromusculoskeletal disorders is discussed. Patient privileges relevant to chiropractic practice are proposed. The Chinese title Yee San or Yee and the English title Doctor are generic terms. Hence, legally “Yee San” and “Doctor” should not be coined by medical practitioners and vice versa. Diagnostic imaging and laboratory procedures are essential for differential diagnosis of neuromusculoskeletal disorders, which may indicate or contraindicate the application of manipulation, and hence are essential for chiropractic practice and clinical research. Proposed amendments of the listed sections of the ordinances and provisions are also outlined.  相似文献   
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This study has shown that the retinae of Prototherian (egg-laying) mammals possess two neuronal types that are present in non-mammalian retinae, but absent or morphologically different in the retinae of Eutherian (placental) mammals. First, endogenous serotonin-like immunoreactivity has been localized in a population of presumptive amacrine cells in the platypus retina, the first such report in a mammalian retina. Second, the protein kinase C-immunoreactive (PKC-IR) bipolar cells in the echidna retina appear similar to the PKC-IR bipolars in the chicken retina, in that their dendrites give rise to a Landolt's club and their axons are multistratified. By contrast, the PKC-IR rod bipolar cells in the rabbit and in the brushtail possum, a Metatherian (marsupial) mammal, have no Landolt's clubs and their axons form terminal lobes in the innermost stratum of the inner plexiform layer.  相似文献   
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Summary Gene therapy is the delivery of genetic material to specific cell types of an organism to alter its physiology or function. This technology is being explored as a means of treating diseases caused by deficiencies of hepatic gene products. The two diseases being used as models for hepatic gene therapy are classical phenylketonuria (PKU) and haemophilia B. Vectors derived from adenoviruses can be used to completely correct these diseases in animal models. The phenotypic correction generated in these studies is transient, and cannot be duplicated by vector readministration. The transient nature of transgene expression results from the destruction of the virally-transduced cells by a cellular immune response directed against the late viral gene products that are also expressed in the target cells. The inability to repeatedly administer virus is caused by a humoral immune response directed against viral proteins present at the time of infusion. If the host immune response is suppressed, transgene expression can persist for 6 months or more. These findings suggest that host immunomodulation in combination with further modification of the adenoviral vector to reduce or eliminate late viral gene expression may permit long-term expression of potentially therapeutic gene products in mammalian liver.  相似文献   
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PURPOSETo evaluate the efficacy, safety, and results of direct thrombolytic therapy in intracranial dural sinus thrombosis by infusion of alteplase (recombinant tissue plasminogen activator).METHODSNine patients were treated during a 2-year period for intracranial dural sinus thrombosis. A microcatheter was placed directly into the thrombus in the dural sinus via the transfemoral route. Thrombolysis was initiated with a rapid injection of 10 mg of alteplase over 10 minutes, followed in 3 hours by a continuous infusion of 50 mg, then a continuous infusion at 5 mg per hour until complete thrombolysis or a total dose of 100 mg per day had been reached. Repeat thrombolysis was tried the following day if complete recanalization did not occur at 100 mg per day.RESULTSSuccessful recanalization with improvement of symptoms was achieved in all cases. Time required for complete thrombolysis was between 8 and 43 hours. The total dose of alteplase ranged from 50 to 300 mg. Complications of a small intrapelvic hemorrhage and oozing at a femoral puncture site occurred in separate cases, but were not related to the amount of infused alteplase. MR venograms obtained 1 to 4 weeks after the procedure showed no evidence of reocclusion of the dural sinuses.CONCLUSIONDirect fibrinolytic therapy with alteplase is safe, fast, and effective in treating dural sinus thrombosis. However, to prevent hemorrhagic complications, further studies are required to determine its optimal dose and proper rate of administration.  相似文献   
80.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
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