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981.
The authors report their experience of anterolateral bilateral approach of cervical spine. They underline the advantages and inconvenience of this route and discuss the indications. 相似文献
982.
983.
Cancer risk after evaluation for infertility 总被引:3,自引:0,他引:3
L A Brinton L J Melton G D Malkasian A Bond R Hoover 《American journal of epidemiology》1989,129(4):712-722
To evaluate cancer risk by various causes of infertility, the authors conducted a retrospective cohort study among 2,335 women evaluated for infertility at the Mayo Clinic between 1935 and 1964. Most cancers occurred at expected frequencies, with the exception of cancers of the thyroid (standardized incidence ratio (SIR) = 2.6) and other endocrine glands (SIR = 6.7), although analyses were based on small numbers. Patients with progesterone deficiencies (31 per cent of the study subjects) had a 20 per cent higher cancer risk than did those with other causes of infertility, with excesses deriving primarily from cancers of the lung, cervix, ovary, and thyroid and from melanoma. Breast cancer risk, however, was not elevated in either patients with progesterone deficiencies (SIR = 0.9) or patients with other causes of infertility (SIR = 1.0). Examination of other parameters of infertility, including age at evaluation, type of infertility (primary vs. secondary), and years of attempted conception, showed no elevated risks of breast cancer in any subgroup. These results fail to support previous studies that have linked progesterone deficiencies among infertile women to elevated breast cancer risk. However, the data suggest a possible involvement of a progesterone deficiency in the etiology of other cancers, particularly thyroid cancer and melanoma. 相似文献
984.
A case of systemic lupus erythematosus (SLE) with focal involvement of the rectum is reported. The lesion roentgenologically resembled a malignant tumour and was resected. Histologic examination disclosed only typical SLE changes in a very restricted area, with the remaining gastrointestinal tract unaffected. This appears to be the first report of focal colitis as a complication of SLE. The case points the importance of suspecting symptoms from any organ system in patients with connective tissue disorders to be manifestations of that underlying pathology. 相似文献
985.
986.
987.
The cell-free medium of isolated human glomeruli exhibited a procoagulant activity and stimulated thromboxane (TXB2) synthesis in human platelets in a dose-dependent manner. The amount of TXB2 measured was 16-fold higher than what could have been predicted (TXB2 synthesized by the platelets under control conditions plus TXB2 present in the glomerular supernatant). The lipid extract of the glomerular supernatant and its purified fraction including the fatty acids was still able to stimulate--although at a lesser degree--TXB2 synthesis in platelets. Stimulation was abolished after treatment of this fraction by charcoal or albumin. Gas chromatography/mass spectrometry analysis demonstrated the presence in the purified glomerular fraction of several long-chain saturated or monoenoic fatty acids at a total concentration of 80 microM with the following order of abundance: stearic, palmitic, myristic and oleic acids. Addition to human platelets of these same exogenous synthetic acids resulted in a dose-dependent stimulation of TX synthesis. It was maximum with three or four fatty acids tested in combination, but still present with myristic acid used separately. Arachidonic acid was absent in the glomerular supernatant. Thus the stimulation observed could not be related to a greater availability of substrate. Fatty acids did not act on platelets through a non-specific detergent effect since addition of high doses of detergents inhibited TXB2 formation in platelets. The combination of fatty acids from glomerular origin identified in the present study represents a novel factor involved in the control of intracapillary hemostasis, but different from the procoagulant activity common to many tissues.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
988.
A general overview of the literature concerning the development of diabetic neuropathic arthropathy is discussed. A case report is presented dealing with spontaneous fractures of the lesser metatarsal in a patient with an amputated hallux and peripheral neuropathy secondary to diabetes mellitus. 相似文献
989.
The authors' 5-year experience in the management and care of prostatic carcinoma are summarized. Their method differs essentially from earlier practice. They have found a new diagnostic and therapeutic method by introducing the TECO irradiation therapy, extensively using bone scintigraphy, by introducing cytostatics, extensively applying the prostate-specific acid phosphatase and by performing rectal biopsy of the prostate. They describe their own observations on the diagnostics and therapy of prostatic carcinoma. They stress that none of the therapies is the method of choice, the use of the various kinds of treatment are defined by strict indications. They state that care of prostatic cancer patients is highly important because only observation of the course of the disease may ensure the evaluation of treatment results and the indication of the adequate therapeutic method. 相似文献
990.
A Pilc 《Polish journal of pharmacology and pharmacy》1987,39(6):691-713
Chronic treatment of rats with imipramine or electroconvulsive shock evokes a significant decrease in binding of [3H]-clonidine to homogenates from the rat brain cerebral cortex. The decrease in binding is accompanied with a functional hyposensitivity of alpha 2-adrenoceptors as measured by attenuation of several central effects of clonidine (e.g. attenuation of clonidine-induced hypothermia, sedation, inhibition of noradrenaline formation). The influence of these antidepressants on alpha 2-adrenoceptors may be of importance in the context of data showing that prolonged treatment with these drugs attenuates the cAMP formation after noradrenergic stimulation, and that the alpha 2-adrenoceptors together with beta-adrenoceptors contribute to the formation of the second messenger. The prolonged administration of imipramine and electroshock, as well as other antidepressant treatments, e.g. administration of the monoamine oxidase inhibitor pargyline or atypical antidepressants such as trazodone, mianserin citalopram, fluoxetine, inhibit the interaction between beta- and-alpha-adrenoceptors (with the alpha 2-subtype playing a major role) and may thus contribute to the phenomenon known as the beta-adrenoceptor down-regulation. The inhibition of the interaction between alpha and beta-adrenoceptors by antidepressants may occur in multiple ways: 1. by lowering the number of beta-adrenoceptors; 2. by lowering the number of alpha 2-receptors (e.g. after imipramine or ETC); 3. by a shift of alpha 2 receptors to a higher affinity state, which represents a desensitized form of the receptor (e.g. decrease in Kd after imipramine or citalopram); 4. by a shift to an antagonist preferring state of the receptor (e.g. after treatment with fluoxetine or trazodone); 5. by a combination of the mentioned above. The functional interaction between alpha and beta adrenoceptors is presumably not dependent upon the integrity of the noradrenergic system, as it not only occurs but also is enhanced in reserpinized or 6OHDA treated rats. 相似文献