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991.
A pseudocyst of the pancreas in a 6-year-old girl persisted for 2 months despite bowel rest and nutritional support. Following percutaneous introduction of a catheter into the cyst under ultrasound guidance and external catheter drainage for 11 days, the pseudocyst resolved completely and permanently. Nonoperative percutaneous techniques for drainage of pancreatic pseudocysts in children may be an effective alternative to surgical intervention.  相似文献   
992.
Immunotherapy, also called desensitization, is effective in treating allergic rhinitis, insect sting venom hypersensitivity and probably allergic asthma. Administration of gradually increasing doses of the sensitizing antigen induces several immunological changes. The humoral responses include an increase in specific IgG titer, a decrease in specific IgE titer with blunting of its seasonal rise, and an increase in the specific anti-idiotype antibody titer. Cellular changes include diminished responsiveness of the patient's lymphocytes to stimulation by allergen as measured by thymidine incorporation. This is accounted for by the generation of suppressor cells specific for the allergen. These suppressor cells also induce suppression of IgE production by mononuclear cells. An additional effect that is attributed to IT is a decrease in basophil sensitivity to the allergen as measured by histamine release. The clinical correlates of these changes are not clear. Currently, none of the responses can be used as a tool for assessing the response in the treated individual patient. Although the increase in specific IgG was shown to correlate with the clinical response in patient groups, it is not applicable to the individual patient. Currently the best parameter for assessing clinical response is probably the increase in the ratio between the specific IgG and the specific IgE. However further studies are warranted to evaluate the significance of the change in anti-idiotype antibodies, basophil histamine release and perhaps immunological changes yet to be discovered.  相似文献   
993.
The angiotensin converting enzyme (ACE) inhibitor [3H]SQ29,852 identified a single high affinity recognition site (defined by 10.0 microM captopril) in the human temporal cortex (pKD 8.62 +/- 0.03; Bmax 248 +/- 24 fmol mg-1 protein, mean +/- S.E.M., n = 4). ACE inhibitors and thiorphan competed to a similar level for the [3H]SQ29,852 binding site in the human temporal cortex with a rank order of affinity (pKi values mean +/- S.E.M., n = 3), lisinopril (9.49 +/- 0.02), captopril (9.16 +/- 0.08), SQ29,852 (8.58 +/- 0.04), epicaptopril (7.09 +/- 0.08), fosinopril (7.08 +/- 0.05) and thiorphan (6.40 +/- 0.04). Since this rank order of affinity is similar to the affinity of these compounds to inhibit brain ACE activity it is concluded that [3H]SQ29,852 selectively labels the inhibitor recognition site of ACE in the human temporal cortex.  相似文献   
994.
995.
A 16-month old baby developed severe respiratory failure because of acute laryngitis and required mechanical ventilation. Intubation was complicated by aspiration and development of chemical pneumonia. Following 4 days of treatment the child was successfully extubated. Thirty six hours after extubation the patient again developed respiratory failure and on chest X-ray pneumomediastinum was seen and later evidence of a mediastinal abscess. Conservative treatment, with antibiotics, effected complete cure.  相似文献   
996.
997.
Serum lipids were estimated in 10 children during the acute phase of hepatitis A and following recovery.Two to 4 days after the appearance of the first symptoms a significant increase in serum lipids (total cholesterol, triglycerides and total phospholipids) was found in all children. This increased concentration persisted throughout the active phase regardless of other liver function tests which showed a gradual improvement. 30 days after the start of the disease all serum lipids returned to normal levels.In serum triglyceride fatty acids a gradual decline in the relative linoleic acid concentration was seen. This may be due to faulty absorption of fat or to increased utilization of carbohydrates during recovery.In the major phospholipid fractions an increase in lecithin and a decrease in lysolecithin was seen in most children. This may indicate a defect in the hydrolysis of lecithin to lysolecithin.  相似文献   
998.
Receptor-ligand dissociation constants are usually calculated from the displacement curve of a radioactively labeled ligand bound to the receptor. The formula used is restricted to cases in which the concentration of receptor is negligible compared to the concentration of both the displacing ligand and the radioactive ligand used. In this study, we rigorously derive a simple equation that can be used for calculating receptor-ligand dissociation constants for any set of experimental conditions. A linearized form of this equation provides a convenient plot from which the dissociation constant of the displacing ligand can be directly obtained. The plot is also a test for the competitive mode of binding. This exact equation now allows us to estimate the error incurred by the conventionally used equations. Similarly, we show that for competitive inhibition in enzymology, one can derive the analogous formula. Our new formula is free of the usual restrictions--namely, that the enzyme concentration is very small compared to the concentration of both the substrate and the inhibitor. It may therefore be applied to any set of experimental conditions.  相似文献   
999.
Three women with neurohypophyseal diabetes insipidus, treated for prolonged periods, including pregnancy, with L-deamino-8-d-arginine vasopressin, gave birth in our hospital. Two of the infants had severe congenital heart disease, one of which was associated with trisomy 21. The third baby, born prematurely, presented with mild intrauterine growth retardation; at the age of 21 months, the boy had severe failure to thrive, hypotonia, and motor retardation. These three cases raise doubts as to the safety of diabetes insipidus or its treatment in pregnancy.  相似文献   
1000.
A Jewish Sephardi family is reported in which 16 members are affected (15 females and 1 male) with inverted nipples. The one affected male and his brother also have gynecomastia. Under the assumption that this trait is transmitted as an autosomal dominant, linkage studies were done but were not revealing. Further family and investigative studies are needed in this disorder to understand better its pathogenesis and precise mode of genetic transmission.  相似文献   
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