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51.
In 1969, Opitz et al. reported the first case of G Syndrome (Opitz-Frias Syndrome). They presented their clinical observations on 4 brothers from the 'G Family' who shared a constellation of findings with a generalised tendency to midline defects. Major manifestations of this multiple congenital anomaly syndrome include hypertelorism, prominent forehead, cleft lip and palate, narrow palpebral fissures with epicanthal folds, dysphagia, stridor, laryngotracheal oesophageal clefts, and hypospadias. The most significant manifestation of a midline field developmental defect in these infants is aspiration which poses the greatest threat to life. Urgent evaluation should include a water-soluble contrast oesophagram and aerodigestive endoscopy. In addition to repair of the laryngeal cleft, which occurs in approximately 30% of the cases, a tracheostomy, feeding gastrostomy, and Nissen fundoplication are often needed. We report a male infant born with G. syndrome. BBB Syndrome (Opitz Syndrome) is also discussed which bears a striking resemblance to the G Syndrome; in fact, they may be variants of the same allelic syndrome.  相似文献   
52.
The fingers of seven women with primary Raynaud's phenomenon (PRP), 10 female controls, seven men with vibration induced white finger (VWF), and eight male controls were exposed to vibration and the relative change in finger capillary blood flow was measured by an atraumatic 133xenon washout technique without and during proximal nervous blockade. All four groups showed a vasoconstriction to vibration (p less than or equal to 0.02) which was abolished by proximal nervous blockade. Women with PRP had an augmented response to vibration (p less than 0.01) and men with VWF had a normal response (p greater than 0.10) when compared with that of their respective sex matched controls. The results show the existence of a vibration elicited central sympathetic vasoconstrictor reflex in the normal finger and in fingers affected by PRP and VWF. The results indicate a hyperreactivity of the central sympathetic nervous system in PRP and VWF and a dysfunction of the peripheral sensory nerve fibres in subjects with VWF. The described vibration test may be of guidance in the differentiation of PRP from VWF.  相似文献   
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Impact of clinical history on fracture detection with radiography   总被引:3,自引:0,他引:3  
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.  相似文献   
56.
Health behaviour during pregnancy was examined before and after a comprehensive health campaign targeted at pregnant women in Odense, Denmark. Furthermore, lifestyle habits were compared before and during the campaign with similar habits in Aalborg, Denmark. All 13,815 pregnant women (equal numbers from each city) were enrolled in the study, and 11,980 gave information on eating, drinking, and smoking habits during pregnancy. Data collection in both cities took place from April 1984 to April 1987. The campaign, which was entitled "Healthy Habits for Two", ran from April 1985 to April 1987 in the city of Odense only. No significant change in health behaviour in the Odense area was noted after the start of the campaign.  相似文献   
57.
Comparable pathological changes in the mitral valve have been described in dogs, pigs and human patients with myxomatous mitral valve disease (MMVD), i.e., primary mitral valve prolapse. The progressive myxomatous changes are probably a response to repeated impact on the leaflets, and endothelial stress or damage probably plays a central role in the pathogenesis. Little, however, is known about the vasoactive substances that mediate the subendothelial changes. The aim of this study was to investigate the expression of nitric oxide synthase (NOS) in canine mitral valve leaflets and to relate the findings to MMVD changes. The mitral valve was taken post mortem from 12 dogs (six males and six females) and a whole valve NADPH (the reduced form of nicotinamide-adenine dinucleotide phosphate) diaphorase (NADPH-d) reaction was performed. Macroscopical (semiquantitative) and microscopical (computer image analysis) evaluations of the staining due to NADPH-d activity were performed at four specific areas of the valve and related to microscopical signs of MMVD and gross signs of thickening or prolapse, or both. Macroscopically, the NADPH-d colour grade was correlated with the degree of MMVD (P=0.01). In addition, endothelial NADPH-d staining intensity was correlated with macroscopical signs of disease (P=0.004) as well as with collagen degeneration (P=0.008) and deposition of mucopolysaccharides (P=0.02). Age, gender and specific area of the valve did not seem to influence the NADPH-d activity. In conclusion, increased NADPH-d activity, suggesting increased NOS expression, was found in areas of the mitral valve with myxomatous changes. This indicates that nitric oxide (NO) may play a role in the pathogenesis of MMVD in dogs.  相似文献   
58.
Pasteurella multocida causes fowl cholera, a highly contagious and severe disease in chickens and water fowls. The disease is not well described in less intensive production systems, including scavenging family poultry production in developing countries. P. multocida was isolated from 25.9% of healthy-looking ducks and 6.2% of chickens from free-range family poultry farms and at slaughter slabs at market. On experimental infection with 1.2 to 2.0 x 10(8) organisms of the P. multocida type strain (NCTC 10322(T)), 12-week-old chickens expressed fowl cholera clinical signs significantly more times (372 signs) than those of 4-week-old, 8-week-old and 16-week-old chickens (173, 272 and 187 signs) and more signs were severe. In family ducks the 8-week-old birds expressed clinical signs significantly more times (188 signs) than those of the other age groups (117, 80, and 83 signs, respectively) and severe signs were more frequent. P. multocida transmitted from seeder birds (n=12) to sentinel birds (n=30), which developed clinical signs, and in some cases lesions of fowl cholera allowed bacterial re-isolation, whether infected ducks served as seeders for chickens or chickens served as seeder for ducks. This study has documented the occurrence of P. multocida among healthy-appearing family poultry in a tropical setting, and demonstrated that age susceptibility is highest in 12-week-old family chickens and 8-week-old family ducks when challenged with a low-virulent strain of P. multocida. It has further demonstrated that cross-transmission of fowl cholera may happen between family ducks and chickens, and vice versa.  相似文献   
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HbhA of Mycobacterium tuberculosis is a multifunctional binding protein, binding to both sulfated sugars such as heparin and to human complement component C3. HbhA may therefore interact with host molecules and/or host cells during M. tuberculosis infection and play a role in the pathogenesis of this bacterium. The purpose of this study was to use allelic exchange to create an M. tuberculosis strain deficient in expression of HbhA to determine whether this protein's C3-binding activity plays a role in the pathogenesis of M. tuberculosis. An in-frame, 576-bp unmarked deletion in the hbhA gene was created using sacB as a counterselectable marker. Southern blotting and PCR analyses confirmed deletion of hbhA in the DeltahbhA mutant. The DeltahbhA mutant strain grew at a rate similar to that of the parent in broth culture and in J774.A1 murine macrophage-like cells but was deficient in growth compared to the parent strain in the lungs, liver, and spleen of infected mice. In addition, the DeltahbhA mutation did not reduce binding of M. tuberculosis to human C3 or to J774.A1 cells in the presence or absence of serum, suggesting that in the absence of HbhA, other molecules serve as C3-binding molecules on the M. tuberculosis surface. Taken together, these data indicate that HbhA is important in the infectivity of M. tuberculosis, but its ability to bind C3 is not required for mycobacterial adherence to macrophage-like cells. Using the DeltahbhA mutant strain, a second M. tuberculosis C3-binding protein similar in size to HbhA was identified as HupB, but the role of HupB as a C3-binding protein in intact organisms remains to be determined.  相似文献   
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