Liver changes in protein malnutrition. An experimental study in rats

Congenital rubella syndrome has a wide variety of severe ophthalmic and systemic complications. A worldwide rubella epidemic from 1963 to 1965 affected thousands of infants. This is a 20 year follow up study of patients with congenital rubella syndrome analysing the prevalence of ophthalmic disorders, associated systemic problems, and correlations among these defects. The authors statistically analysed 125 cases of congenital rubella seen in the Mayo clinic ophthalmology department over a 32 year interval. Most patients were young adults. Ocular disease was the most commonly noted disorder (78%), followed by sensorineural hearing deficits (66%), psychomotor retardation (62%), cardiac abnormalities (58%), and mental retardation (42%). Multiorgan disease was typical (88%). Ocular disease and hearing loss were frequently associated (53% had both) but not significantly correlated. A similar association existed between ocular and cardiac disease. Cataracts and microphthalmia were significantly correlated with poor visual acuity (each p < 0.0001). Glaucoma was significantly correlated with cataracts (p = 0.0002) and microphthalmia (p = 0.0024) but not poor visual acuity. Four patients with microphthalmia developed late onset glaucoma. No significant association was found between gestational age at time of maternal infection and the incidence of individual ocular conditions. However, several cardiac disorders were significantly associated with gestational age. Although new cases of congenital rubella are rare, surviving victims continue to challenge the ophthalmic and medical communities with a wide range of ocular and systemic disorders.     

Effects of irradiation on osseointegration before and after implant placement: a report of three cases

Three patients irradiated as a part of cancer treatment, both before and after placement of endosseous implants, were studied. Total irradiation doses varied from 80 to 195 Gy in the tumor/implant area. Implants failed at a rate of 64.2% during a 3-year follow-up period. All patients developed osteoradionecrosis in the tumor cavities adjacent to the implants. The combined effects of the pre- and postoperative irradiation, in conjunction with the placement of implants, appear to challenge the limits of osseointegration. Until further knowledge is obtained regarding how such highly radiated tissue should be handled, it is recommended that if anchorage of craniofacial prostheses is attempted according to osseointegration principles, it should be performed with the utmost care.     

Effects of the ability to locomote on infants' social and exploratory behaviors: An experimental study.

In Exp I, 20 normal 6.5–10 mo old infants who were unable to locomote independently were observed for 10 min in an infant "walker" and for 10 min out of the walker. Exp II compared effects of walker-assisted locomotion with effects of independent locomotion in 16 7–20 mo olds who were able to creep or crawl. Age parameters were closely similar to those of the 1st sample. Results indicate that the 2 modes of locomotion, walker-assisted or independent, afforded similar experiences within a standard environment, but experiences quite different from those of the nonlocomoting infant. Some behaviors actually emerged as a function of the ability to locomote; others changed in frequency or were extended to new features of the environment. In addition, all classes of behaviors measured were known from other studies to affect adults' behavior toward infants. Therefore, changes in these behaviors should lead to changes in infants' social experiences. The systematic reorganization of experiences, both social and nonsocial, as a result of locomotion has implications for social, perceptual, cognitive, and language development. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An experimental study of the effectiveness of brainstorming.

In the study of conditions favorable to creativity 2 different ways of conducting brainstorming groups were compared. 3 groups each composed of 7 university students were given instructions to uncritically invent names for 3 kinds of articles; 3 other groups of students each composed of 7 persons were given instructions to also invent names for the same articles only to do so critically. 150 different students rated the invented names of both groups for quality. "For each product, the noncritical condition produced a greater number or responses than the critical condition… . If it is the purpose of problem solving to produce a specific number of ideas of highest possible quality, these best ideas will tend to be of higher or equal quality when the noncritical method is used." From Psyc Abstracts 36:02:2HD45W. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An experimental study of the double bind hypothesis.

The primary aim of the study was to assess whether persons highly conversant with the double bind concept could reliably identify such communication in letters, and, if so, whether its presence or absence was related to the fact of the letter having been written by the parent of a schizophrenic or nonschizophrenic person. The interjudge correlations of the double bind judges were very low, indicating that their judgments regarding presence or absence of double bind communication were not reliable. Other judges achieved statistically significant interjudge reliability and were able to differentiate between letters written by parents of patients and a comparison group. It was concluded from these results that a more critical appraisal of the double bind concept is indicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tooth mobility and resolution of experimental periodontitis. An experimental study in the dog

The aim of the present experiment was to study alterations in the mobility of teeth that occurred during resolution of experimentally induced periodontitis lesions in the dog. 5, 1-year-old, beagle dogs were used in the study. The left and right 4th, 3rd, and 2nd mandibular premolars (4P4, 3P3, 2P2) served as experimental teeth. Periodontal tissue breakdown was initiated by placing plaque-collecting cotton-floss ligatures around the neck of the experimental teeth. The ligatures were replaced to the level of the receding gingival margin 1 x every month. On Day 120, the ligatures were removed and debridement was performed. A groove, parallel to the long axis of the mesial root, was prepared in the mesio-buccal surface of the crowns of 2P and P2. Guided by the groove and with a probing force of 0.5 N, a probe was inserted into the buccal gingival pocket of the mesial root and was attached to the buccal surface. Biopsies including both the mesial and distal root of 2P and P2 and the surrounding hard and soft tissues were harvested. The biopsy procedure was repeated in a similar manner 15 days (i.e. Day 135) and 3 months (i.e. Day 225) after ligature removal in the 4th (4P4) and 3rd (3P3) premolar regions. After fixation, decalcification and sectioning, the biopsy material was exposed to histometric and morphometric measurements. Assessment of the mobility of the experimental teeth was performed on Days 120, 135 and 225 using the Periotest system.(ABSTRACT TRUNCATED AT 250 WORDS)     

Decadron in the treatment of cerebral abscess. An experimental study

Forty rabbits were inoculated with Streptococcus pyogenes or Staphylococcus aureus to produce cerebral abscesses. One-third of the rabbits received no treatment and served as controls. One-third received dexamethasone (Decadron) plus an appropriate antibiotic. One-third received only the appropriate antibiotic in the same dosage. The animals were sacrificed 10 days after inoculation and the brains examined. In the control group, an abscess at the stage of granulation tissue encapsulation containing the inoculated organisms was found. The surrounding brain showed a marked inflammatory response. In the Decadron plus antibiotic group, necrotic lesions were found containing the inoculated organisms and surrounded by relatively normal brain. In the group treated with antibiotic alone, healed glial scars were found in relatively normal brain. Our findings are discussed with reference to the medical literature regarding the influence of glucocorticoids on the inflammatory response and the efficacy of antibiotics when this response is suppressed.     

Influence of metal implants on infection. An experimental study in rabbits

We implanted cylinders of cobalt-chrome or titanium, with smooth or porous surfaces, into rabbit bones which had been inoculated with suspensions of Staphylococcus aureus in various doses. The bacterial concentration required to produce infection of porous-coated titanium implants was 2.5 times smaller than that necessary to infect implants with polished surfaces. Porous-coated cobalt-chromium implants required bacterial concentrations that were 40 times smaller than those needed to infect implants with polished surfaces, and 15 times smaller than those required to infect porous-coated titanium implants. The other advantages and disadvantages of the various implants, such as improved osseointegration, larger ion-release surfaces, surface wear and relative stiffness, must be weighed against the higher infection rates in the porous-coated implants, and particularly in the cobalt-chromium implants.     

Percutaneous reinsertion of the nucleus pulposus. An experimental study

STUDY DESIGN: An analysis of the histologic changes in intervertebral discs after percutaneous reinsertion of the nucleus pulposus in rats. OBJECTIVE: To devise a way to delay further disc degeneration resulting from spinal deformity and the adverse effects of various treatments. SUMMARY OF BACKGROUND DATA: The role of the nucleus pulposus of the intervertebral disc described by many investigators has not been fully clarified. METHODS: Disc herniation was induced in the tails of 112 Wistar rats, using a fixation device between the 5th and 8th coccygeal vertebrae. After percutaneous nucleotomy at coccygeal vertebrae 5-6 and 6-7, fresh nucleus pulposus, cryopreserved nucleus pulposus, or an artificial substitute was inserted into the intervertebral disc at coccygeal vertebrae 5-6. Two, 4, or 8 weeks after reinsertion, disc sections from each coccygeal level were studied histopathologically. RESULTS: In the groups with reinsertion of fresh or cryopreserved nucleus pulposus, degenerative changes of the disc with the reinserted nucleus at coccygeal vertebrae 5-6 were milder than those of the disc without reinsertion at coccygeal vertebrae 6-7. However, no apparent benefit from reinsertion was observed in the group with artificial substitutes. CONCLUSIONS: Early reinsertion of the nucleus pulposus (fresh or cryopreserved) delays degeneration of such disc materials as the anulus fibrosus, endplate, and remaining nucleus pulposus.     

Reversibility of medialization laryngoplasty. An experimental study

Medialization laryngoplasty has become a routine procedure for cases of unilateral vocal fold paralysis. In certain clinical situations, it may become desirable to reverse the procedure and remove the implant. This process was studied experimentally in eight dogs in a chronic model of induced canine phonation. A silicone polymer implant was inserted to medialize one normal vocal fold for a period of 1 month, after which it was removed. Motion of the cricoarytenoid (CA) joint and induced phonation were studied weekly while the implant was in place, and for another month following implant removal. Significant abnormalities were found even with this relatively short period of implantation. With the implant in place, impairment of CA joint mobility was found in seven of the eight dogs, precluding phonation. A dense fibrous capsule rapidly developed around the implant, making its removal technically difficult. Following implant removal, a gradual return to normal function was found in only three of the eight dogs. One of the animals had evidence of neural injury, while four had intact neural function but impaired mobility or fixation of the CA joint. Medialization laryngoplasty should not be considered a reversible procedure. The clinical implications of these findings are discussed.     

An experimental study of cross-cultural norm conflict.

"An experimental study was conducted in which normative conflict of foreign students was examined. From a treatment of norms as force-fields, predictions were made about the resolution of intergroup norm conflict under two conditions of situational potency of membership. It was hypothesized that the resolution of intergroup norm conflict favors the norm of the group whose situational potency is increased. The results obtained did not show the clarity necessary for a definitive validation of the hypotheses. The major analyses led to acceptable levels of significance in only half of the tests made; nevertheless, all the results presented a consistent pattern in harmony with the theoretical formulation." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of right hemithoracic irradiation on ceftazidime penetration into the alveolar space in rats

We experienced with three patients with pulmonary dirofilariasis found in resected lungs. Two patients showed abnormal shadows on chest roentgenograms without symptoms. Another patients had chest discomfort. All patients underwent diagnostic thoracotomy. Histopathological examination showed necrotic granulomatous lesions surrounded by fibrous tissue and transverse section of Dirofilaria immits was found. It has been an increasing reported disease. It is important to keep in mind the possibility of dirofilariasis.     

Regeneration of the spinal ventral roots. An experimental study in cats

From a clinical standpoint recovery of spinal nerve roots is less likely than that of peripheral nerves, despite their identical structures. This may be due to several factors including the length of gap to be bridged, changes in the proximal stump or neuroma, and chromatolysis. In this paper we discuss the roles of some of these factors in relation to the neuronal depopulation in the spinal cord anterior horn area following section of the anterior root. The lack of growth or the successful growth of the axon through the gap in the root influences the degree of depopulation in the anterior horn area.     

Translocation of bacteria due to direct mucosal damage caused by Gastrografin. An experimental study in newborn rats

The aim of this study was to investigate the role of heat-shock proteins after heat-shock stress on the post-ischemic recovery of cardiac mechanical and endothelial function following a prolonged cardiac arrest. Isolated working rat hearts were subjected to a cardioplegic arrest for 4 hours at 4 degrees C. Three groups (n = 8 in each) were studied: (1) control, (2) sham-treated, and (3) heat-shocked rats. Postischemic recovery of cardiac output and endothelial function (as percent of preischemic control values) was 57.8% +/- 2.8% and 20.8% +/- 3.9% in group 1, 50.9% +/- 4.0% and 26.3% +/- 5.9% in group 2, and 74.0% +/- 2.4% and 51.2% +/- 8.0% in group 3, respectively. Both postischemic myocardial and endothelial function were improved by heat stress.     

An experimental study of internalization fantasies in schizophrenic men.

Explored the types of internalization fantasies involving the constructs (or concepts or fantasies) of mother that are ameliorative in schizophrenia, using 120 18–65 yr old male schizophrenics (nonorganic). Four groups of 30 Ss received a subliminal experimental stimulus designed to activate a different fantasy of internalization as well as a subliminal neutral control message. The experimental messages were "Mommy and I are one," "Mommy and I are the same," "Mommy is inside me," and "Mommy and I are alike"; the control message was "People are walking." Assessments of pathological thinking and behavior were made before and after the presentation of each stimulus. Only the stimulus "Mommy and I are one" was effective in reducing pathology. Findings lend strong support to the contention that fantasies of oneness identification with the "good" mother are ameliorative for schizophrenics. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effectiveness of cigarette advertisements on women: An experimental study.

Investigated three factors that could influence subjects' reactions to print advertisements for cigarettes. A total of 115 college women were shown cigarette ads that varied on two dimensions: whether an attractive model was shown and whether a general or specific warning label was shown. One half of the women were pretested on their beliefs about the hazards of smoking prior to seeing the ads; all of the women completed a posttest beliefs measure. Ratings of the attractiveness, persuasiveness, and credibility of the ads were collected, and the smoking status of subjects was assessed. Results indicated that specific warnings on ads can act as a counterinfluence to an ads' appeal by making it appear less attractive and less persuasive than if the ad contained only a general warning. This effect was especially true for smokers. Subjects also rated an ad as more attractive, more persuasive, and less credible when it showed an attractive model than when it did not. Being pretested on their beliefs about the hazards of smoking resulted in high attractiveness and persuasion ratings and in smokers' recalling and recognizing more of the specific warnings that appeared on ads. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

湿法黄金精炼提纯工艺试验研究

针对经典的电解法精炼黄金的一些不足,提出了湿法化学方法提纯,并对金山矿黄金精炼提纯进行了试验研究。通过批量试验结果表明,采用该方法提纯,金的纯度可达９９．９９％。而且工艺流程简单、操作技术条件易掌握、污染少、生产周期短、黄金积压少。