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301.
In 22 renal transplant recipients, 23 open-lung biopsy procedures were performed. There were two (8.7%) biopsy-related complications (hemorrhage and pneumothorax) and five deaths (22.7%), although the deaths could not be definitely related to the biopsy procedure itself. Seventeen biopsy specimens yielded specific diagnoses, and six were nonspecific. The mortality rate for the patients with specific diagnoses was not significantly different from that of patients with nonspecific diagnoses (25% vs. 16.7%). Other factors analyzed, such as age, diabetes, hypoxia, leukopenia, and donor source, did not affect the result of biopsy. We conclude that the patient's underlying disease and added immunosuppressive therapy are the factors most responsible for the clinical outcome. We suggest that without early treatment of the infectious agents, the mortality rate of the group with specific diagnoses would likely have been higher.  相似文献   
302.
The ability of intramuscular injections of gonadal steroids to exert a positive feedback action on LH secretion was investigated in the ovariectomized hen. Plasma LH was measured by radioimmunoassay. Single injections of progesterone (dose range: 0.05-10 mg/kg) or oestradiol benzoate (dose range: 0.01-1 mg/kg) did not result in an increase in plasma LH concentration. After priming with 0.1 mg oestradiol benzoate/kg on alternate days for 7 days and with 0.5 mg progesterone/kg on days 5, 6 and 7, a single injection of progesterone on day 8 (dose range: 0.1-2 mg/kg) caused the plasma LH concentration to start increasing after 15 to 30 min. Peak LH concentration was reached around 1.5-2 h after injection. The magnitude of LH response to progesterone was dose related. In contrast, a single injection of oestradiol benzoate (dose range: 0.01-1 mg/kg) failed to stimulate LH release in the oestrogen-progesterone primed ovariectomized (O-P-OVX) hen. A single injection of testosterone (dose range: 0.1-2.0 mg/kg) failed to stimulate LH release in ten out of 12 O-P-OVX hens. A small increase in LH secretion was observed in the two remaining birds. When oestrogen or progesterone was omitted from the priming schedule, a LH positive feedback response to a single injection of progesterone was not observed. Increasing or decreasing the mount of oestrogen or progesterone in the priming schedule modified the LH response to a single injection of progesterone on the day following the last priming injection. This suggested that a critical oestrogen to progesterone ratio was required to prime the LH positive feedback mechanism. It is suggested that, in the hen, the release of LH is facilitated by the positive feedback effect of a combination of oestrogen and progesterone in a two-phase process. The first is the priming phase, which depends on the presence in the blood of oestrogen and progesterone; the second is the ind .uctive phase, which depends only on an incremental change in plasma progesterone concentration. Oestrogen is not involved in the induceive phase.  相似文献   
303.
A case is reported of subcutaneous emphysema of the neck in association with emphysematous cystitis and uncontrolled diabetes. Problems in its management are discussed. Anatomic pathway for the spread of the gas from the bladder to the subcutaneous tissues of the neck and the back is speculated.  相似文献   
304.
When studying enzymic and fluorescence properties of myosin and DTNB-treated myosin in the presence of K+, Na+, Li+, NH4+, Ca2+ and Mg2+ cations the following results were obtained. By the intrinsic protein fluorescence techniques no essential structural changes of myosin molecule at the dissociation of the DTNB light chain and activation myosin ATPase in the presence of different cations were found. The decrease of K+-EDTA-, the increase of Mg2+-activated and the stability of Ca2+-activated myosin ATPase may be the result of the modification of SH1 or SH2 sulfhydryl groups when treating the DTNB myosin in our conditions. The different level of decrease of the K+- and NH4+-activated myosin. ATPase may be explained by the fact, that myosin sulfhydryl groups have different effects on the activation of its ATPase by these cations.  相似文献   
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307.
As a result of ultraviolet light and coal tar therapy, a white ring (Woronoff) may develop in the normal skin adjacent to psoriatic plaques. Injection of prostaglandin E2 (PGE2) 1 cm outside of Woronoff ring produced redness in the ring, demonstrating that vessels within the ring were not unresponsive to PGE2. Whole skin homogenates from Woronoff ring contained an inhibitor of prostaglandin synthesis that was not found in uninvolved skin that was obtained from either psoriatics or normal controls. Prostaglandin E2 levels in the ring were one third of those in uninvolved skin from either psoriatics or normal controls. These findings suggest that the white ring that surrounds ultraviolet-light-treated psoriatic plaques is produced by a local inability to synthesize PGE2 in response to an ultraviolet light stimulus, resulting from the presence of an inhibitor of prostaglandin synthesis.  相似文献   
308.
Inactive mutants of the nystatin-producing organism Act. noursei were selected. When 2 of them were cultivated together, nystatin biosynthesis was restored. The substance or substances restoring the antibiotic biosynthesis was excreted into the culture broth. It had non-protein nature and was stable on storage. Reduction of the nystatin biosynthetic chain proceeded without changes in the cultivation conditions.  相似文献   
309.
Study of the hormonal activity of the gonads of 97 males suffering from chronic alcoholism was undertaken to investigate the effects on hormonal secretion. An increased synthesis of androgens and estrogens was noted. The regularity of this increased with the duration of alcoholism. It is thought that the increased synthesis of sex hormones in chronic alcoholism is a defense adaptation directed to reducing the unfavorable effects of high concentration of alcohol in the blood. Alcoholism treatment involving teturam along with abstinence of alcohol caused a decrease in the functional activity of gonads, indicating the reversibility of this effect. The nature of functional alteration in the synthesis of sex hormones shows that it plays an essential role in the genesis of sexual impotence in alcoholism, through dyshormonal disruption of the endocrinal system.  相似文献   
310.
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