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71.
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73.
Congenital radioulnar synostosis(CRS) is a rare anomaly and approximately 400 cases were reported worldwide so far. CRS is the failure of the longitudinal segmentation and the persistence of the cartilaginous anlage between the radius and ulna during the seventh week of development that results in a persistent bridge of tissue. Here we are discussing on a case of 25yrs old, male patient with bilateral congenital synostosis. On the left hand the pronation and supination movements are restricted completely where as on right side 10 degree of supination and 20 degree of pronation is possible. Radiologically in our patient synostosis is classified as type II variety by Wilkie(1914)1 classification and type IV by the Cleary and Omer classification(1985). The position of forearm was not found to be related to subjective functional limitation, or employment status. Main line of treatment is surgical mainly rotational osteotomy but is rarely indicated. Our patient is not able to rotate his forearm especially on the left side still he has no functional limitation so he has refused for the operative treatment. No study has objectively compared the preoperative functional limitation of the patients with their postoperative functional improvement in order to justify surgical intervention In the authors opinion the only major factor that is to be taken into consideration of operative treatment is functional limitation to the patient.  相似文献   
74.
Burkholderia cepacia selective agar (BCSA) has previously been devised for isolation of B. cepacia from respiratory secretions of patients with cystic fibrosis and tested under research laboratory conditions. Here we describe a study in which BCSA, oxidation-fermentation polymyxin bacitracin lactose agar (OFPBL), and Pseudomonas cepacia agar (PCA) were compared in routine culture procedures for the ability to grow B. cepacia and inhibit other organisms. Three hundred twenty-eight specimens from 209 patients at two pediatric centers and 328 specimens from 109 adults were tested. Plates were inoculated, incubated, and read for quality and quantity of growth at 24, 48, and 72 h. Five (1.5%) specimens from 4 (1.9%) children and 75 (22.9%) specimens from 16 (14.7%) adults grew B. cepacia complex. At 24, 48, and 72 h, BCSA achieved 43, 93, and 100% detection, respectively; OFPBL achieved 26, 84, and 96%, respectively; and PCA achieved 33, 74, and 84% detection, respectively. Quality was assessed as pinpoint or good growth. At 24 h, most cultures growing B. cepacia complex had pinpoint colonies. By 48 and 72 h, 48 and 69% of B. cepacia complex cultures, respectively, had good growth on BCSA, while on OFPBL 19 and 30%, respectively, had good growth and on PCA 11 and 18%, respectively, had good growth. BCSA was superior to OFPBL and PCA in suppressing organisms other than B. cepacia complex; 40 non-B. cepacia complex organisms were isolated from BCSA, 263 were isolated from OFPBL, and 116 were isolated from PCA. We conclude that BCSA is superior to OFPBL and PCA in its ability to support the growth of B. cepacia complex and to suppress other respiratory organisms.  相似文献   
75.
Specificity of color connectivity between primate V1 and V2   总被引:7,自引:0,他引:7  
To examine the functional interactions between the color and form pathways in the primate visual cortex, we have examined the functional connectivity between pairs of color oriented and nonoriented V1 and V2 neurons in Macaque monkeys. Optical imaging maps for color selectivity, orientation preference, and ocular dominance were used to identify specific functional compartments within V1 and V2 (blobs and thin stripes). These sites then were targeted with multiple electrodes, single neurons isolated, and their receptive fields characterized for orientation selectivity and color selectivity. Functional interactions between pairs of V1 and V2 neurons were inferred by cross-correlation analysis of spike firing. Three types of color interactions were studied: nonoriented V1/nonoriented V2 cell pairs, nonoriented V1/oriented V2 cell pairs, and oriented V1/nonoriented V2 cell pairs. In general, interactions between V1 and V2 neurons are highly dependent on color matching. Different cell pairs exhibited differing dependencies on spatial overlap. Interactions between nonoriented color cells in V1 and V2 are dependent on color matching but not on receptive field overlap, suggesting a role for these interactions in coding of color surfaces. In contrast, interactions between nonoriented V1 and oriented V2 color cells exhibit a strong dependency on receptive field overlap, suggesting a separate pathway for processing of color contour information. Yet another pattern of connectivity was observed between oriented V1 and nonoriented V2 cells; these cells exhibited interactions only when receptive fields were far apart and failed to interact when spatially overlapped. Such interactions may underlie the induction of color and brightness percepts from border contrasts. Our findings thus suggest the presence of separate color pathways between V1 and V2, each with differing patterns of convergence and divergence and distinct roles in color and form vision.  相似文献   
76.
The constitutional t(11;22)(q23;q11) is the only known recurrent, non-Robertsonian translocation. To analyze the genomic structure of the breakpoint, we have cloned the junction fragments from the der(11) and der(22) of a t(11;22) balanced carrier. On chromosome 11 the translocation occurs within a short, palindromic AT-rich region (ATRR). Likewise, the breakpoint on chromosome 22 has been localized within an ATRR that is part of a larger palindrome. Interestingly, the 22q11 breakpoint falls within one of the 'unclonable' gaps in the genomic sequence. Further, a sequenced chromosome 11 BAC clone, spanning the t(11;22) breakpoint in 11q23, is deleted within the palindromic ATRR, suggesting instability of this region in bacterial clones. Several unrelated t(11;22) families demonstrate similar breakpoints on both chromosomes, indicating that their translocations are within the same palindrome. It is likely that the palindromic ATRRs produce unstable DNA structures in 22q11 and 11q23 that are responsible for the recurrent t(11;22) translocation.  相似文献   
77.
Kim EK  Jeong JH  Youn HS  Koo YB  Roe JH 《Current genetics》2000,38(5):283-290
The gene structure and expression of the linear mitochondrial plasmids of the white-rot fungus Pleurotus ostreatus, pMLP1 and pMLP2, were analyzed. Cleavage by proteinase K and exonucleases indicated that the 5′ ends of pMLP1 and pMLP2 DNAs were associated with terminal proteins. Nucleotide sequencing of the entire pMLP1 DNA revealed that it consists of 9,879 bp with terminal inverted repeat (TIR) sequences of 381 bp. The end sequence of TIR in pMLP1 is 3′-CCCCC-5′, similar to those of Escherichia coli phage PRD1. The pMLP1 plasmid harbors two long open reading frames (ORF1 and ORF2) and at least one minor ORF (mORF1). The deduced product of ORF1 is homologous to RNA polymerases of yeast mitochondria and several bacteriophages, whereas that of ORF2 is homologous to the protein-primed DNA polymerases of family B type. The mORF1 encodes a highly basic protein, most likely a TIR-binding protein, with no apparent sequence homology in the database. Expression of the predicted gene products from pMLP1 in mitochondria was demonstrated by Western blot analysis using antibodies against various expressed regions of pMLP1 ORFs. A plasmid-free strain, generated by curing with ethidium bromide, did not express any of these gene products. Terminal proteins of 70 kDa (TP1) and 73 kDa (TP2) were identified from pMLP1 and pMLP2, respectively. Western blot analysis indicated that TP1 was generated from the N-terminal half of the full-length product of ORF2 encoding a putative DNA polymerase. Received: 9 February 2000 / Accepted: 18 July 2000  相似文献   
78.
H.D. Lu  G. Chen  D.Y. Ts'o  A.W. Roe 《NeuroImage》2009,44(3):636-646
In optical imaging experiments, it is often advantageous to map the field of view and to converge the eyes without electrophysiological recording. This occurs when limited space precludes placement of an electrode or in chronic optical chambers in which one may not want to introduce an electrode each session or for determining eye position in studies of ocular disparity response in visual cortex of anesthetized animals. For these purposes, we have developed a spot imaging method that can be conducted rapidly and repeatedly throughout an experiment. Using small 0.2°–0.5° spots, the extent of the imaged field of view is mapped by imaging cortical response to single spots, placed at different positions (0.2° steps) in either the horizontal or vertical axes. By shifting the relative positions of two spots, one presented to each eye, eye convergence can be assessed to within 0.1° resolution. Once appropriate eye alignment is determined, stimuli for further optical imaging procedures (e.g. imaging random dot stimuli for study of disparity responses) can then be confidently placed. This procedure can be quickly repeated throughout the experiment to ensure maintained eye alignment.  相似文献   
79.
Amyloid involvement of the breast is infrequently reported and may have clinical and radiological features suspicious for a primary breast malignancy. We describe a case of amyloid of the breast in which asymptomatic mammographic findings were suspicious for locally recurrent disease in a patient with previously treated breast cancer.  相似文献   
80.
BACKGROUND: The risks of colorectal cancer and adenoma, the precursor lesion, are believed to be influenced by dietary factors. Epidemiologic evidence that cereal fiber protects against colorectal cancer is equivocal. We conducted a randomized trial to determine whether dietary supplementation with wheat-bran fiber reduces the rate of recurrence of colorectal adenomas. METHODS: We randomly assigned 1429 men and women who were 40 to 80 years of age and who had had one or more histologically confirmed colorectal adenomas removed within three months before recruitment began to a supervised program of dietary supplementation with either high amounts (13.5 g per day) or low amounts (2 g per day) of wheat-bran fiber. The primary end point was the presence or absence of new adenomas at the time of follow-up colonoscopy. Subjects and physicians, including colonoscopists, were unaware of the group assignments. RESULTS: Of the 1303 subjects who completed the study, 719 had been randomly assigned to the high-fiber group and 584 to the low-fiber group. The median times from randomization to the last follow-up colonoscopy were 34 months in the high-fiber group and 36 months in the low-fiber group. By the time of the last follow-up colonoscopy, at least one adenoma had been identified in 338 subjects in the high-fiber group (47.0 percent) and in 299 subjects in the low-fiber group (51.2 percent). The multivariate adjusted odds ratio for recurrent adenoma in tile high-fiber group, as compared with the low-fiber group, was 0.88 (95 percent confidence interval, 0.70 to 1.11; P=0.28), and the relative risk of recurrence according to the number of adenomas, in the high-fiber group as compared with the low-fiber group, was 0.99 (95 percent confidence interval, 0.71 to 1.36; P=0.93). CONCLUSIONS: As used in this study, a dietary supplement of wheat-bran fiber does not protect against recurrent colorectal adenomas.  相似文献   
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