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31.
32.
C Whitehead BA L D Sanders PhD M Rosen CBE FCAnaes J O Robinson PhD 《International journal of clinical practice》1991,45(4):263-264
SUMMARY In order to assess the reliability of drug information supplied by day-stay cases, 85 consecutive patients were interviewed. A comparison of the interview answers with the details previously volunteered during the admission procedure showed an increase of 80% in the information given by the patient. While the detailed interviewing technique is time-consuming and may not be infallible, this substantial increase in information highlights problems in the current routine. 相似文献
33.
Laparoscopic bile duct injuries. Risk factors, recognition, and repair. 总被引:18,自引:0,他引:18
R L Rossi W J Schirmer J W Braasch L B Sanders J L Munson 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(5):596-601; discussion 601-2
Records of 11 patients undergoing biliary reconstruction after laparoscopic cholecystectomy are reviewed. Ductal injuries resulted from failure to define the anatomy of Calot's triangle. Risk factors include scarring, acute cholecystitis, and obesity. Presenting findings included anorexia, ileus, failure to thrive, pain, ascites, and jaundice. All patients required hepaticojejunostomies, which were multiple and above the hepatic bifurcation in four patients. Given the extensive nature of these injuries and the frequent need for intrahepatic anastomosis and early stenosis of repairs by referring physicians, we recommend reconstruction be undertaken by an experienced hepatobiliary surgeon. To avoid injuries, a greater appreciation of risk factors and anatomic distortion and variance and strict adherence to principles of dissection and identification of anatomic structures are suggested. The use of cholangiography and a low threshold for conversion to the open procedure are advised. 相似文献
34.
Nicotine discrimination and self-administration in humans as a function of smoking status 总被引:2,自引:2,他引:0
Nicotine’s discriminative stimulus effects may be critical to understanding reinforcement of tobacco smoking. It is not known
whether regular nicotine exposure produces tolerance or sensitivity to these effects. In this study, male and female smokers
(n = 11) and never-smokers (n = 10) were trained to discriminate 20 μg/kg nicotine by nasal spray from placebo (0) on day 1. On day 2, both groups were
tested on generalization of this discrimination across intermittent presentations of 0, 3, 6, 12, and 20 μg/kg nicotine in
random order. Quantitative and quantal behavioral discrimination tasks, used in previous research, were employed. On day 3,
subjects were instructed to self-administer sprays from the 20 μg/kg nicotine versus 0 bottles in a concurrent-choice procedure.
All but one subject (female smoker) learned reliably to discriminate 20 μg/kg nicotine from placebo (≥ 80% correct) on day 1. Nicotine-appropriate responding on day 2 was attenuated in smokers versus never-smokers at 20 μg/kg
on the quantitative task and at 12 μg/kg on the quantal task, suggesting tolerance. There was no difference in responding
at other doses. Smokers also showed attenuated responses on the subjective measure of “head rush”, which was associated with
discrimination responding in both groups. Nicotine self-administration was significantly greater in smokers versus never-smokers,
who self-administered nicotine below chance levels, and was inversely related to discrimination behavior in never-smokers
but unrelated in smokers. Women smokers showed less change in nicotine-appropriate responding across generalization doses,
reported less confidence in discriminating training doses during acquisition on day 1, and tended to self-administer less
nicotine on day 3. These results indicate that smokers may become tolerant to the discriminative stimulus effects of nicotine,
perhaps promoting increased use.
Received: 1 October 1996/Final version: 28 January 1997 相似文献
35.
J H Sanders 《North Carolina medical journal》1989,50(10):584-585
36.
J E Sanders 《Paediatrician》1991,18(1):76-81
As increasing numbers of children are surviving beyond the 1st decade after marrow transplantation and increasing numbers of children are receiving marrow transplants each year, the delayed effects related to the transplant procedure itself, the original disease, and/or the transplant preparative regimen are becoming apparent. Late effects related to the transplant procedure include those of engraftment stability, the chronic immunosuppression of chronic graft-versus-host disease and delayed immunologic recovery. Recurrent disease is the major late effect related to the patient's original disease. The late effects which may be related to previous therapy administered and/or the transplant preparative regimen include abnormalities of neuroendocrine function, ocular problems, dental developmental abnormalities in young children, central nervous system dysfunction and the development of secondary malignancies. To improve the quality of life of marrow transplant recipients and to prevent some of the growth and development abnormalities which may occur, an awareness of the problems encountered to date is needed. 相似文献
37.
Polyacrylamide gel electrophoresis of acid phosphatase from prostatic tissue reveals one more band than seminal plasma. It was attempted to ascertain which subcellular fraction was responsible for that intracellularly localized enzyme. Prostatic epithelium from patients with prostatic hyperplasia was homogenized, and a lysosomal and microsomal fraction were prepared by differential centrifugation. These two fractions were further centrifuged on an isopycnic Percoll gradient. The intracellularly localized form of acid phosphatase was associated with the lysosomal as well as with the microsomal fraction. In a fused rocket electrophoresis experiment these acid phosphatases cross-reacted with antiserum from seminal plasma. After neuraminidase treatment of the acid phosphatase of lysosomal and microsomal origin, only one activity band was found in polyacrylamide gels. It is concluded that only one acid phosphatase protein exists in prostatic epithelium; differences in electrophoretic mobility are caused mainly by different amounts of sialic acid residues, coupled to the same protein backbone. 相似文献
38.
Abuye C Tsegaye A West CE Versloot P Sanders EJ Wolday D Hamann D De Wit TF Fontanet AL 《Journal of clinical immunology》2005,25(2):127-133
To study the determinants of CD4% and CD4 counts among HIV-negative Ethiopians, and to identify factors susceptible to explain the low CD4 counts observed among Ethiopian subjects. Cohort studies among factory workers in Akaki and Wonji, Ethiopia. Clinical and laboratory examinations, including determination of HIV serological status and T-cell subsets, were performed during follow-up visits every six months. In addition, micronutrients (retinol, carotenoids, tocopherol, transferrin receptor, and selenium) plasma concentrations were determined in a subset of 38 HIV-positive and 121 HIV-negative participants. HIV-negative participants with at least one CD4 count measurement were 157 females in Akaki, 203 males in Akaki, and 712 males in Wonji. CD4 counts were independently and positively associated with body mass index (through an increase in lymphocyte counts), female gender (through an increase in CD4%), cigarette smoking (through an increase in CD4%), khat chewing (through an increase in both lymphocyte counts and CD4%), and Akaki study site (through a large increase in lymphocyte counts compensating a decrease in CD4%). Intestinal parasitic infections were not associated with CD4% or CD4 counts. Retinol, carotenoids, and -tocopherol plasma concentrations decreased with HIV infection and advancing immunosuppression, but were not associated with CD4 counts among HIV-negative subjects. Low body mass index among Ethiopians may have contributed to their overall low CD4 counts. Other factors remain to be elucidated. 相似文献
39.
We have used an antibody against a TGFβ peptide fragment to localize this growth factor in the early chick embryo from laying to the ten-somite stage of development. Western blotting showed that the antibody reacted with both mammalian TGFβ1 and chicken TGFβ3. By immunocytochemistry we find that at the earliest developmental stage (stage X of Eyal-Giladi and Kochav) immunoreactivity to this antibody is primarily located in the cells of the area opaca and marginal zone, as well as in the most peripheral edge cells of the blastoderm. The yolk is non-reactive, except in a highly localized region subjacent to the edge cells. This pattern persists at stage XII, and at both stages individual isolated cells in the epiblast and hypoblast are also reactive. By the time to gastrulation, reactivity in the epiblast is polarized to the ventral extremity of the cells, and again some isolated cells in this layer are intensely immunoreactive. At this stage also, the endoderm cells, particularly those underlying the primitive streak, are positive, as are the mesoderm cells lateral to the streak. At somite stages, the neuroepithelium is not reactive but the ectoderm lateral to it is strongly positive. At the caudal primitive streak levels of early somite embryos, the ectoderm and endoderm are immunoreactive while the mesoderm loses the reactivity it showed at the early gastrulation stages. The neuroepithelial cells later show reactivity at their apical poles, and, as at the earlier stages, individual cells show intense labelling. These results indicate that TGFβ1 and/or TGFβ3 immunoreactivity is developmentally regulated from very early stages of morphogenesis in the chick, and together with data from earlier functional studies, suggest that this factor has roles in embryonic axis formation and in blastoderm expansion. © 1994 Wiley-Liss, Inc. 相似文献
40.
H. F. Helander S. S. Sanders L. L. Shanbour W. S. Rehm 《Acta physiologica (Oxford, England)》1975,95(4):353-363
Functional and morphological properties of the in vitro frog gastric mucosa were studied during and after exposure to very hypotonic (? 25 mOsM) solutions. Within 20 min the acid secretory rate decreased to zero, but it returned to normal levels after isotonic fluids had been restored. The potential difference (PD) dropped within the first minutes after the exposure to hypotonic solutions, and became inverted. Following the return of isotonic conditions the PD increased to levels higher than in the controls. The electrical resistance increased about 10–fold during the hypotonic period, but decreased to near normal values when isotonic conditions were restored. By light and electron microscopy the cells of the hypotonic mucosae appeared greatly swollen, and the alterations were assessed by morphometric methods. The gland lumina were almost obliterated, and the lamina propria was reduced to about 60% of its former volume. After the return to isotonic conditions normal morphology was restored. It is conceivable that the great increase in resistance during the hypotonic period was caused by the occlusion of the gland lumina. Quantitative analyses of the Na, K, and C1 tissue concentrations indicated a large loss of these ions during the hypotonic state. Presumably the epithelial cells in the hypotonic mucosae avoid bursting by rapidly letting large numbers of ions exit, which results in a cellular osmolarity close to that of the bathing fluids. 相似文献