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101.
Penetration of human sperm into a underlaying Percoll layer is very effective in isolating forward motile sperm. A plastic funnel, the bottom of which having been plugged with a 1.0-ml disposable syringe, was used as a separation vessel. Ejaculated semen (2.0 ml) was loaded on 2.0 ml of 80% Percoll; after allowing to stand 60 min, forward motile sperm penetrating into the lower part of Percoll layer (1.0 ml) were collected into the syringe. Sperm motility was enhanced to 91.5% +/- 3.3% regardless of the original motility (48.4% +/- 14.6%) with a mean recovery of 34.1% +/- 6.8% (n = 22). Measurement of residual lactate dehydrogenase activity suggested that seminal plasma was excluded almost completely from the purified sperm fraction.  相似文献   
102.
103.
Cardiac contusion following blunt chest trauma remains a diagnostic problem because of a lack of sensitive diagnostic tests. This study evaluated thallous chloride Tl 201 single-photon-emission computed tomography in a series of 48 patients following blunt chest trauma. Of the 48 patients, 23 had normal scans. None of these patients proved to have serious arrhythmias during three days of continuous monitoring. Of 25 patients with abnormal or ambiguous studies, five (20%) developed serious arrhythmias requiring therapy. Single-photon-emission computed tomography scanning thus was sensitive in indicating that group of patients at risk of serious arrhythmias, and may therefore prove to be a useful screening test to determine the need for hospitalization and arrhythmia monitoring following blunt chest trauma.  相似文献   
104.
105.
The derivatives (2) of 3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl) acrylic acid (2b) were synthesized. The compounds (3a-g) in which bromo, methoxy, nitro, amino or acetamido group was introduced on the benzene ring of the derivatives (2) and the compounds (3h-k) in which acryloyl moiety was introduced on the 6- or 7-position of the benzofuranone skeleton also synthesized. Furthermore, propionic acid derivatives (4a-c), acetic acid derivatives (4d-g), formic acid derivatives (4h-k) and oxyacetic acid derivatives (5) were prepared by converting the acryloyl moiety of the derivatives (2) into propionyl, acetyl, formyl and oxyacetyl groups. These compounds were tested for antiulcer activities. Among these compounds, 1-[3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl)acryloyl]piperidine (2d) and 4-[3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl)acryloyl] morpholine (2g) were found to have stronger antiulcer activities.  相似文献   
106.
107.
To assess the pathophysiological role of atrial natriuretic factors in the regulation of blood pressure, we studied the effect of chronic infusion of a synthetic atrial natriuretic factor of 25 amino-acid residues on blood pressure and sodium-water excretion. Experimental subjects were rats with hypertension made by chronic infusion of vasopressin on regular intakes of sodium or on sodium loading with 1% NaCl as drinking water. When a subdepressor dose (150 micrograms/kg/day) of synthetic atrial natriuretic factor was delivered via an osmotic minipump into the jugular vein simultaneously with 7.2 U/kg/day of vasopressin infused intraperitoneally by another osmotic minipump, the expected elevation of systolic blood pressure was completely inhibited. This was not accompanied by any changes in urine volume and urinary sodium excretion. The antihypertensive effect was sustained throughout the experimental period lasting 3 days in rats on regular sodium intake (p less than 0.01) or on sodium loading with 1% NaCl as drinking water (p less than 0.01). These results indicate that a subdepressor dose of synthetic atrial natriuretic factor can modulate the vasopressor effect of vasopressin. Therefore it is suggested that an atrial natriuretic factor may be involved in the regulation of blood pressure via its antagonizing effect to vasopressin.  相似文献   
108.
109.
Protein kinase C (PKC) has been implicated in enhancing cellular sensitivity to cis-diamminedichloroplatinum(II) (CP). We have synthesized a series of novel analogues of lyngbyatoxin A (7-linalylindolactam V), a natural tumor promoter and a potent activator of PKC, and investigated the effects of these synthetic compounds on PKC activity and the antiproliferative activity of CP. Lyngbyatoxin A was as effective as phorbol esters, such as 12-O-tetradecanoylphorbol-13-acetate, in enhancing the sensitivity of HeLa cells to CP. A 24-h pretreatment of HeLa cells with 1 to 100 nM lyngbyatoxin A caused an approximately 9-fold sensitization to CP. All analogues of lyngbyatoxin A that retained the lactam ring portion of the molecule but contained different hydrophobic substituents at C-7 including indolactam V (ILV), tert-butyl-ILV, or n-hexyl-ILV increased cellular sensitivity to CP in a concentration-dependent manner. Maximum cellular sensitization to CP (9-fold) was seen with 10 nM n-hexyl or tert-butyl compounds, and ILV devoid of any C-7 substitution required higher concentrations (1 microM) for equivalent sensitization. The ability of lyngbyatoxin A analogues to sensitize cells to CP correlated directly with their ability to activate PKC in vitro. Synthetic analogues that lacked the lactam ring structure neither activated PKC nor sensitized cells to CP. The C-9 epi analogue of n-hexyl-ILV was less effective than the corresponding natural stereoisomer in activating PKC as well as sensitizing cells to CP. Exposure of HeLa cells to 100 nM lyngbyatoxin A for 24 h caused a substantial decrease in cellular PKC activity to 20% of the untreated control value, but a similar treatment of cells with n-hexyl- or tert-butyl-ILV led to only a 25% reduction in PKC activity. Concentrations of ILV (e.g. 1 microM) that sensitized HeLa cells to CP caused no down-regulation of PKC. Thus, on the basis of results with these novel lyngbyatoxin A analogues, we conclude that activation but not down-regulation of PKC is necessary for sensitization of HeLa cells to CP.  相似文献   
110.
Summary A new gas-liquid chromatographic (GLC) determination of cholesterol sulfate (CS) and dehydroepiandrosterone sulfate (DHEAS) for a biochemical diagnosis of recessive X-linked ichthyosis (RXLI) is described. Although the GLC method for determination of CS is known to be more sensitive than the thin layer chromatographic (TLC) method, the former method has not been widely employed because of its complicated pre-purification steps. The present method allows us to measure the serum levels of CS and DHEAS without tedious purification steps such as multiple conventional column chromatography and preparative thin layer chromatography. Sulfated steroids are rapidly purified with a commercially available mini disposable cyclohexylsilane-bonded phase (CH) column, CH BOND ELUT, and the purified steroids after desulfation are converted to water-resistant tert-butyldimethylsilyl ether derivatives for the GLC analysis on dual 2 m glass columns packed with 2% XE-60 on Chromosorb W.By the present method, serum CS concentrations in RXLI patients were shown to be about 10 times higher than those in patients with ichthyosis vulgaris, carriers of RXLI, and healthy subjects. This method is more suitable not only for a biochemical diagnosis of RXLI but also for studies on the metabolism of sulfated steroids than the previous time-consuming GLC methods.  相似文献   
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