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1.
Martha A. Warpehoski Paul J. Buscemi David C. Osborn Birdwell Finlayson Eugene P. Goldberg 《Calcified tissue international》1981,33(1):211-222
Summary The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found
to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter
ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a “growth
front” on stone surfaces with migration of organic material from the “older” interior. The matrix distribution was not readily
correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations
were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich
surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates
as growth centers. 相似文献
2.
3.
Antibiotic prophylaxis and secondary haemorrhage following transurethral resection of the prostate: a prospective trial 总被引:2,自引:0,他引:2
One hundred and sixty-two patients were studied in a random double-blind controlled trial of co-trimoxazole to prevent secondary haemorrhage following transurethral resection of the prostate (TURP). There was a significant correlation between the incidence of post-operative urinary infection and secondary haemorrhage (P less than 0.05) but no difference between the incidence of bleeding in the treatment and placebo groups. Although infection may play a role in the development of secondary haemorrhage, co-trimoxazole for 10 days does not decrease the incidence of this complication. 相似文献
4.
Guinea pigs were actively sensitized by parenteral injections of ovalbumin (OA), house dust extract (HD) orAscaris suum extract (As) in a variety of multidose regimens. At least 3 weeks after the initial sensitization injection, aerosols of the appropriate antigen were administered to conscious guinea pigs in a double-chamber body plethysmograph. OA elicited the most consistent and intense bronchoconstriction (BC) as measured by decreases in specific airway conductance (sGAW). The airway responses to As were clearly separable into responders and nonresponders. HD produced essentially no BC. However, intense lacrimation and rhinorrhea occurred in all HD-sensitized, but not unsensitized, animals. No late-phase changes in sGAW or increased reactivity to other spasmogens were seen up to 8h after any antigen challenge. Eosinophil influx of magnitude similar to that measured by 24h post-antigen bronchoalveolar lavage (BAL) occurred with all the three antigens. Animals which did not bronchoconstrict to As experienced an equal or greater pulmonary eosinophilia as airway responders. The present data with HD and As suggest that acute BC in response to antigen provocation is not a prerequisite for the eventual pulmonary eosinophilia. The lack of late-phase airway reactions in these models raises a doubt in the direct extrapolation to airway responses in allergic human asthma. The acute lacrimation and rhinorrhea to HD may suggest utility as a model of allergic rhinitis. 相似文献
5.
A recent large increase in Caesarean section (CS) in Italy was the initial stimulus for a study to identify risk factors for CS and, if possible, to suggest strategies to counteract the rise. The study was conducted in three hospitals where a wide range of individual variables was collected from the clinical records and from personal interviews. Crude CS rates and odds ratios were evaluated for each single variable while logistic regression has been used to investigate possible confounding factors. The study involved 1316 consecutive deliveries. Crude CS rates were 29.4%, 15.7% and 16.1%. Variables identified as high risk factors were pre-eclampsia, previous CS, breech and other non-vertex presentations. Antenatal care under an obstetrician working in the same hospital, a low number of antenatal consultations, previous miscarriages, offer (by obstetrician) and request (by women) for CS showed significantly high odds ratios (ORs). Previous live births was strongly negatively associated with CS. No relationship between type of delivery and social status was observed while a physician factor was detected in all three hospitals where rates for different physicians ranged from 0% to 52.8%. Apart from the main medical indications for Caesarean section (previous CS, breech presentation), the results seem to indicate that individual practice style may be an important determinant of the wide variation in the rates of Caesarean delivery. While this may have been suspected before this study, these results are the first hard data to indicate that, in Italy, CS is widely performed for non-medical reasons. 相似文献
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7.
This useful listing of references on radiology administration covers topics from equipment selection to computerization. In addition to available written references, the authors provide information on PC-based access to data bases. 相似文献
8.
The well established differential pulmonary handling of angiotensins I and II indicates the possibility that vascular receptors for the deca- and octa-peptides do not necessarily involve common sites in the renal vasculature either. Experimental findings involving haemodynamic changes within the kidney in anaesthetised and conscious sheep, with utilization of the angiotensins, and also of noradrenaline, are briefly presented; the implications of the intra-renal water and creatinine transfers are discussed, especially as they concern the possible location of angiotensin receptors in the renal blood vessels. Other aspects of the relationships between the peptides are also taken into account particularly with regard to a postulated angiotensin I [NaCl] dependent peritubular capillary antidiuretic action, angiotensin converting enzyme inhibition, Goldblatt clamp induced hypertension and blood flow through the hind-limbs. 相似文献
9.
N. Tait M. L. Greenberg A. J. Richardson R. A. Osborn J. M. Little 《ANZ journal of surgery》1995,65(4):237-241
Frantz's tumour (papillary and cystic tumour) of the pancreas is a rare neoplasm usually seen in young women. It is of low grade malignancy and deserves special note among pancreatic malignancies as it is frequently amenable to local resection and has a good long-term survival rate after excision. Three such cases have been treated at Westmead Hospital, one young male and two females. In two the disease was confined to the pancreas. In one, local invasion outside the pancreas and trans-coelomic spread to the ovaries was present at the time of diagnosis. Complete surgical removal of macroscopic disease was achieved in all three and all remain disease free between 2 and 4 years post-surgery. All have good exocrine and endocrine pancreatic function. These cases are discussed in detail. The need to be aware of this uncommon variant of pancreatic cancer is stressed. Investigation and treatment options are reviewed. The role of cytology studies in diagnosis and the potential for long-term surgical control of this tumour are highlighted on the basis of our limited experience and that presented in recent surgical literature. 相似文献
10.
We investigated the extent of the distribution of polysynaptic connections to the dorsal spinocerebellar tract (DSCT). Recording from a randomly selected population of DSCT units, we found that over 60% responded to maximal stimulation of group I afferent fibers in the gastrocnemius-soleus muscle nerve. Most of the responses had a time course or latency consistent with polysynaptic activation. The extensive distribution of this input into the pool of DSCT neurons suggests that input from muscle nerves in general is widely distributed to these neurons. The results further imply that the DSCT plays a more integrative role in the transmission of information from the hindlimb to the cerebellum than has been previously supposed. 相似文献