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991.
In order to study the biological activity of endogenous digitalis-like substance (DLS) and Na-K-ATPase inhibitor (ATPI), human urine was partially purified and administered to rats, and its effects on the urinary volume, urinary Na excretion and blood pressure (BP) were determined. In addition, the effect on myocardial Na-K-ATPase activity was also measured. After the extraction of 40L of urine with a reversed phase cartridge column (S-fraction), 20 ml of chloroform was added and extraction was repeated. The chloroform layer was applied to an open silica gel column, and at a fraction with ethylacetate: methanol (60: 40, T-1 fraction), DLS and ATPI were eluted at the highest concentration. The water layer was treated with charcoal (D-1 fraction). The acute administration of K-1, T-1 fraction to rats in vivo caused significant rises in urinary volume, urinary Na excretion and BP. In chronic administration of K-1 fraction, urinary Na excretion was significantly elevated and myocardial Na-K-ATPase activity was also significantly suppressed. These results suggest that DLS and ATPI cause increase in the urinary volume and urinary Na excretion and also possess a hypertensive action; and moreover, these substance may affect the heart like cardiotonic steroids and regulate BP by increasing cardiac contractility.  相似文献   
992.
S Raam  D M Vrabel 《Clinical chemistry》1988,34(10):2053-2057
We present evidence to show that monoclonal antibodies to estrogen receptors (ER) in solid phase recognize the secondary estrogen binding sites with moderate to low affinity for estradiol (E2). An excellent quantitative agreement was found in five cytosols between the ER values obtained by the enzyme immunoassay (ER-EIA) and the amount of secondary estrogen binding sites measured by the assay involving dextran-coated charcoal (Clin Chem 1986;32:1496). The immunoreactive protein recognized by the antibody-coated beads, when allowed to react with ER(+) cytosols, is shown to bind [3H]estradiol only when the ligand concentration exceeds 8 nmol/L. Further biochemical and functional characterization of the immunoreactive protein is required to establish similarities/dissimilarities between this protein, high-affinity Type I ER sites, and the secondary sites such as Type II sites.  相似文献   
993.
In einer clusteranalytischen Untersuchung mit 137 Patienten, die einen Parasuizid verübt hatten, wurden 6 Subgruppen unter Berücksichtigung der Klassifikationsvariable “suicide intent” isoliert. Es wurde die Hypothese geprüft, dass sich sowohl die Motivstrukturen als auch die Raten an wiederholten Parasuiziden in Abh?ngigkeit der Clusterl?sung bedeutsam voneinander unterscheiden. Die Ergebnisse unterstützen die Annahme einer zunehmenden Ausdifferenzierung der interpersonell orientierten Motivstrukturen mit sinkendem bzw. einer Einengung der Motivstruktur auf den Todeswunsch mit steigendem “suicide intent”. Es wurden folgende Subgruppen differenziert: eine Suizid-Hochrisikogruppe mit ausschlie?licher Todesintention und -motivation, 2 moderate Suizid-Risikogruppen mit hoher Todesintention und leichten Tendenzen zu interpersoneller Motivation, eine Subgruppe, gekennzeichnet durch eine manipulativ/strategisch orientierte Motivstruktur und auff?llig h?ufigen Parasuizidwiederholungen, eine Subgruppe mit vorrangig appellativ orientierten Motiven, Kontrollverlust und vergleichsweise seltenen Parasuizidwiederholungen und eine Subgruppe mit ambivalenter Motivstruktur (interpersonell und todesorientiert).  相似文献   
994.
Predefined monoclonal antibodies (Mabs) were used in an immunoenzymometric assay to study the immunochemical heterogeneity of lipoproteins and to search for potential epitopes with pathological importance. By measuring apolipoprotein B (apo B) epitopes in patients with and without angiographically documented coronary artery disease and in patients with type IIa hyperlipoproteinemia, we have found that both types of patients have a significant increase in Apo B-containing particles specifically recognized by one Mab (BL3). We have also observed that the effects of fenofibrate on type IIa patients vary greatly depending on the plasma concentrations of various Apo B-containing lipoproteins. The greatest effects occurred in patients with epitopes recognized by BL3. Lastly, by sequential precipitation of specific epitopes by BL3, we have obtained evidence that the residual epitope(s) may be related to one or more lipoprotein particles.  相似文献   
995.
OBJECTIVES: to examine the management and outcome of patients with traumatic popliteal artery pseudoaneurysms with delayed presentation. MATERIALS: over a 2-year period 7 patients with traumatic popliteal pseudoaneurysms presenting to a tertiary referral unit after a delay of 1 month were reviewed. METHODS: a retrospective review of clinical records. RESULTS: the median interval between injury and presentation was 1.5 months (range 1-24 months). Penetrating trauma from gunshot wounds was the cause of the initial vascular injury in 6 patients and a stab wound in one. All patients had large pseudoaneurysms of more than 8 cm filling the popliteal fossa with variable degrees of fixed flexion deformity (FFD) of the knee. Severe FFD of more than 40 degrees was noted in 2 patients and 3 others had mild flexion deformities of 10 to 20 degrees. Six patients underwent repair of the pseudoaneurysm. One patient required an above knee amputation due to an infected false aneurysm. There were no deaths or graft related complications. Despite aggressive post-operative physiotherapy only 2 patients were able to completely straighten the leg at the time of discharge. CONCLUSIONS: in patients with neglected popliteal artery pseudoaneurysms, morbidity is associated with the pre-operative degree of fixed flexion deformity of the knee.  相似文献   
996.
INTRODUCTION: The clinical presentation of morphea varies from localized plaques to generalized eruptions. Its cause remains unknown and medical treatments have often proved unsatisfactory. Studies have previously shown that improvement of hypertrophic scars and fibrotic skin can be achieved with the use of a 585 nm pulsed dye laser (PDL). METHODS: A case of plaque-type morphea was treated with 585 nm pulsed dye laser irradiation at an average fluence of 5.0 J/cm2 at bimonthly time intervals. RESULTS: Marked clinical improvement as evidenced by improved pliability and skin coloration was seen after 4 successive PDL treatments. No side effects or complications were encountered. CONCLUSION: Pulsed dye laser therapy is a viable treatment option for morphea. The mechanism of its effect in this condition remains unknown.  相似文献   
997.
Background: The antidepressant amitriptyline is commonly used orally for the treatment of chronic pain, particularly neuropathic pain, which is thought to be caused by high-frequency ectopic discharge. Among its many properties, amitriptyline is a potent Na+ channel blocker in vitro, has local anesthetic properties in vivo, and confers additional blockade at high stimulus-discharge rates (use-dependent blockade). As with other drug modifications, adding a phenylethyl group to obtain a permanently charged quaternary ammonium derivative may improve these advantageous properties.

Methods: The electrophysiologic properties of N-phenylethyl amitriptyline were assessed in cultured neuronal GH3 cells with the whole cell mode of the patch clamp technique, and the therapeutic range and toxicity were evaluated in the rat sciatic nerve model.

Results: In vitro, N-phenylethyl amitriptyline at 10 [mu]m elicits a greater block of Na+ channels than amitriptyline (resting block of approximately 90%vs. approximately 15%). This derivative also retains the attribute of amitriptyline in evoking high-degree use-dependent blockade during repetitive pulses. In vivo, duration to full recovery of nociception in the sciatic nerve model was 1,932 +/- 72 min for N-phenylethyl amitriptyline at 2.5 mm (n = 7) versus 72 +/- 3 min for lidocaine at 37 mm (n = 4; mean +/- SEM). However, there was evidence of neurotoxicity at 5 mm.  相似文献   

998.
There is considerable interobserver variation in the diagnosis of low-grade squamous intraepithelial lesion that involves mature squamous epithelium. Our aim was to evaluate the utility of MIB-1 immunostaining as an adjunct test to increase diagnostic accuracy. Consecutive cervical biopsies originally diagnosed as normal (n = 26) or low-grade squamous intraepithelial lesion (n = 23) were reviewed by three pathologists to obtain a consensus diagnosis. MIB-1 immunostaining was performed, and positive staining was defined as a cluster of at least two stained nuclei in the upper two thirds of the epithelial thickness. Human papillomavirus (HPV) DNA detection was performed using a polymerase chain reaction assay. All cases were subsequently reclassified as low-grade squamous intraepithelial lesion (LSIL) or normal (NL) when two or three of three gold standard criteria were satisfied (LSIL gold standard criteria = consensus diagnosis of LSIL, HPV+, MIB-1+; NL gold standard criteria = consensus diagnosis of NL, HPV-, MIB-1-). Using the gold standard diagnoses, we have identified that 14 normal cases (36%) were originally overdiagnosed as LSIL, and one LSIL case (10%) was originally underdiagnosed as normal. All MIB-1-positive cases were HPV+ and identified as LSIL in the consensus review. All MIB-1-negative cases were NL by gold standard criteria. The sensitivity (1.0) and the specificity (1.0) of MIB-1 staining for identifying LSIL were superior to the sensitivity (0.9) and the specificity (0.8) of HPV testing. In conclusion, MIB-1 is a highly sensitive and specific marker for identifying low-grade squamous intraepithelial lesion and is helpful in verifying the diagnosis of equivocal cases.  相似文献   
999.
1000.
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