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991.
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The premenstrual syndrome 总被引:1,自引:0,他引:1
PMS is probably a group of entities which include various symptoms that occur during the 7 to 10 days before menstruation and disappear a few hours after the onset of menstruation. The definition of PMS lacks objective criteria. The most common symptoms are irritability, bloating, aggressiveness, mastodynia, and headaches. The prevalence of PMS is estimated at 30 to 40 per cent. PMS is more prevalent among women working outside the home, alcoholics, women of high parity, and women with toxemic tendency; it probably runs in families. The etiology of PMS is no less obscure to us than when it was first described by Frank in 1931. No single theory has been established to explain the entire diversity of PMS symptomatology. The multitude of possible etiologic factors includes psychosocial bases, progesterone deficiency, prolactin excess, thyroid hypofunction, renin angiotensin alternations, antidiuretic hormone excess, decreased colloidosmotic pressure, endorphin activity alternations, serotonin metabolism alternations, prostaglandin action, vitamin deficiency, and such unconventional theories as the ovarian infection or the "yeast overgrowth" theory. A partial resolution of this divergence of hypotheses comes from the biopsychosocial model developed by Keye and Trunnel. According to this model, a biologic, perhaps genetically determined, predisposition to PMS is realized when past and present life experiences, attitudes, beliefs, coping styles, and social forces interact to stress a woman. The diagnosis of PMS is based on establishing a relationship between the luteal phase of the cycle and the symptoms. The evaluation of PMS patients includes the use of a monthly diary to scale the symptoms, a physical examination, and biochemical studies to rule out other disorders. Management includes education, reassurance, and drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
995.
996.
Circulating carcinoembryonic antigen (CEA) levels and their relation to liver function test values were studied in 29 jaundiced patients with benign extrahepatic biliary tract obstruction and inflammation. During the obstructive and inflammatory phase, 15 (52%) of the patients had CEA levels greater than 2.5 ng/ml. Elevated CEA levels were associated more frequently with common bile duct stones (and cholangitis) than with gallbladder stones (and cholecystitis) alone, although this difference was not statistically significant. The former often had values greater than 5.0 ng/ml. The highest values were found in two patients with liver abscesses. T'HE CEA levels returned to normal following relief of obstruction in seven of ten patients and increased in two patients who had progressive inflammation. Serum alkaline phosphatase and bilirubin levels were significantly higher in the patients with elevated CEA levels (p smaller than .05). Serum alkaline phosphatase levels showed a significant positive correlation with CEA levels (p smaller than .02). Patients with obstructive jaundice and elevated CEA levels do not necessarily have cancer. 相似文献
997.
n-Dipropylacetate (nDPA), at a dose of 100 mg/kg, has a facilitating action on the acquisition of conditioned reactions with negative reinforcement in mice. On the other hand, nDPA reduces the number of conditioned reactions with a dose of 200 mg/kg. These effects of nDPA on conditioned behaviour are correlated with the increase of the level of brain gamma-aminobutyric acid, following administration of nDPA. 相似文献
998.
T. Madhavan Edward L. Quinn Earl Freimer Evelyn J. Fisher Frank Cox Keith Burch Donald Pohlod 《Antimicrobial agents and chemotherapy》1973,4(5):525-531
Cefazolin, a new cephalosporin derivative, was studied in the treatment of 105 hospitalized patients with a variety of infections including endocarditis, pneumonia, and urinary and soft tissue infections, and was found to be effective in 104 patients. Cefazolin was also tested in vitro and shown to be effective against staphylococci, pneumococci, Escherichia coli, Klebsiella sp., and Proteus mirabilis by agar dilution method. It was shown to produce high serum levels when administered in a 250- to 1,000-mg intramuscular dose and was well tolerated and free from renal toxicity. Comparison of the results of this study with those from our prior studies on cephaloridine revealed equivalent antibiotic potency, good tolerance to both the agents when given intramuscularly, superior, average blood levels with cefazolin, equal clinical efficacy, and absence of renal toxicity with cefazolin (unlike cephaloridine). Similarly, the results of treatment of pneumococcal pneumonia with intramuscular cefazolin were found to be superior to those for oral cephalexin. 相似文献
999.
1000.
Peter J. Dawson Winston E. Gutteridge Keith Gull 《Molecular and biochemical parasitology》1983,7(3):267-277
We have developed a method for the purification of tubulin from a parasitic nematode using DEAE-Sephadex column chromatography and temperature-dependent assembly. The resulting microtubules were morphologically similar to those obtained from mammalian brain. The nematode tubulin showed similar properties to mammalian tubulin on one and two dimensional polyacrylamide gels, although certain electrophoretic conditions revealed a slight difference in the α-tubulins from mammals and nematodes. This was confirmed by limited proteolytic peptide mapping. The β subunit of nematode tubulin appeared almost identical to that of mammals. Peptide maps of these tubulins were also compared with those of eukaryotic micro-organisms and these results interpreted in terms of the evolution of the tubulin polypeptides and the sensitivity of helminths to antimicrotubular agents. 相似文献