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91.
Dacryocystorhinostomy is performed in patients with naso-lacrimal duct obstruction to bypass the site of obstruction so as to relieve the patient of the irritating and socially embarrassing symptoms of epiphora. We discuss the various epidemiological aspects especially the vast difference by which the females out-number the males in patients undergoing DCR and the likely explanations for this difference in our study on 74 patients which underwent DCR in our institute.  相似文献   
92.
A boy with Duchenne muscular dystrophy and facial dysmorphism in conjunction with Klinefelter's genotype 47XXY is presented; this is an unusual situation with two genetic errors evolving over two generations. Karyotyping should be considered in boys with Duchenne muscular dystrophy who have unusual features.  相似文献   
93.
94.
The present study investigated the expression and distribution of three isoforms of nitric oxide synthase (NOS) in different anatomical regions of the human stomach and in gastric neoplastic tissues by immunohistochemistry using specific antibodies. Intracellular localization of individual isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer tissues had a marked reduction of all three NOS isoforms expression. The expression of the endothelial NOS, neuronal NOS and inducible NOS in the tumor tissue was significantly lower than in normal gastric mucosa (P = 0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the expression of inducible NOS was significantly lower than the expression of both constitutive forms of NOS (P < 0.01). There was a tendency to higher expression of both constitutive forms of NOS in earlier stages T2 of the tumor compared to advanced T4 tumor. In contrast, the expression of inducible NOS was higher than in the advanced T4 tumor than in the earlier stages T2 of the tumor. The mapping of the expression of endothelial NOS, neuronal NOS and inducible NOS in human stomach showed higher expression of NOS isoforms in the distal third than in the proximal third of the stomach (P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is greater expression of NOS in the stomach corpus and in antrum than in the proximal third of the normal human stomach mirroring the anatomical predilection of common pathological changes in this part of the human stomach. Furthermore, there was loss of the expression of individual isoenzymes in gastric neoplasms.   相似文献   
95.
The incidence of Papillary Thyroid Carcinoma in a Thyroglossal Cyst is rare. Only about 160 cases have been reported in the last 85 years. We report a case of Thyroglossal Cyst who underwent Sistrunk &#x2019;s Operation. The Cyst was reported to contain a focus of papillary thyroid carcinoma. In the absence of metastases in thyroid gland and neck nodes, only thyroid suppression with Thyroxine was given. After I year of follow-up there are no metastases. The importance of Sistrunk&#x2019;s operation lies not only in complete removal of Thyroglossal Cyst but also in management of small foci of Papillary thyroid Carcinoma.  相似文献   
96.
Neurofilaments (NF), the intermediate filaments of the neuronal cytoskeleton, provide mechanical stability to the cell. High-molecular-weight NF (NFH) comprises a heavily phosphorylated carboxyl terminal ("sidearm") domain which helps determine interfilament spacing distances. Experimental evidence suggests that dephosphorylation greatly increases the rate and extent of proteolysis of NFH. Because NF proteolysis has been implicated as one pathogenic mechanism underlying cell death following traumatic brain injury (TBI), we analyzed the patterns of acute NFH damage in relation to phosphorylation state following focal, concussive, controlled cortical impact (CCI) brain injury in mice. Brains from C57BL/6 male mice (n = 4 injured and n = 1 sham per time point) were evaluated 5 min, 15 min, 90 min, 4 h, and 24 h following CCI injury (1 mm depth, 5 m/s). Immunohistochemistry was performed using antibodies that recognize epitopes on either dephosphorylated (d-NFH) or phosphorylated (p-NFH) sidearms or on the core (c-NFH) domain. As early as 5-15 min postinjury, immunoreactivity for d-, p-, and c-NFH decreased in the ipsilateral cortex, and hippocampal CA3, CA1, and dentate areas. This marked decrease of NFH labeling occurred in the absence of notable cell loss. Furthermore, partial recovery of NFH labeling was observed as early as 90 min postinjury in the cortex and by 24 h postinjury in hippocampal CA3 and dentate. The results of this study suggest that both phosphorylated and dephosphorylated NFH are vulnerable almost immediately following focal brain injury in mice, but that injured neurons may have an adaptive capability to partially restore this important cytoskeletal protein.  相似文献   
97.
The number of times an article is cited in scientific journals reflects its impact on a specific biomedical field or specialty and reflects the impact of the authors’ creativity. Our objective was to identify and analyze the characteristics of the 100 most frequently cited articles published in journals dedicated to general surgery and its close subspecialties. Using the database (1945–1995) of the Science Citation Index of the Institute for Scientific Information, 1500 articles cited 100 times and more were identified and the top 100 articles selected for further analysis. The 100 articles were published between 1931 and 1990, with more than two-thirds of them published after 1960. The mean number of citations per article was 405, (range 278–1013). Altogether, 84 of the articles originated from North America (USA 78, Canada 6) and the UK (12). New York State led the list of U.S. states with 14, and Harvard and Columbia University led the list of institutions with 6 articles each. The 100 articles were published in 10 surgical journals led by theAnnals of Surgery (n = 40), followed bySurgery (n = 15), Archives of Surgery (n = 12), Surgery, Gynecology and Obstetrics (n = 11), and British Journal of Surgery (n = 10). A total of 80 of the articles reported clinical experiences, 6 were clinical review articles, and 14 dealt with basic science. Eighteen articles reported a new surgical technique and six a prosthetic device. Gastrointestinal surgery and trauma and critical care led the list of the surgical fields, each with 25 articles, followed by vascular surgery (n = 15). Thirty-four persons authored two or more of the top-cited articles. This list of the top-cited papers identifies seminal contributions and their originators, facilitating the understanding and discourse of modern surgical history and offering surgeons hints about what makes a contribution a "top-cited classic." To produce such a "classic" the surgeon and his or her group must come up with a clinical or nonclinical innovation, observation, or discovery that has a long-standing effect on the way we practice—be it operative or nonoperative. Based on our findings, to be well cited such a contribution should be published in the English language in a high-impact journal. Moreover, it is more likely to resonant loudly if it originates from a North American or British "ivory tower."  相似文献   
98.
99.
From the stems of Indigofera longeracemosa, a novel abietane diterpenoid, indigoferabietone was isolated. The structure was established by spectral techniques. The inhibitory activity of indigoferabietone (1) tested against Mycobacterium tuberculosis and Candida albicans, and the antibacterial activity tested against Staphylococcus aureus, Proteus vulgaris, and Escherichia coli were found to be significant.  相似文献   
100.
Twelve children with vertebrobasilar artery stroke are reported (seven males, five females; aged 6 months to 15 years). Patient 1 showed an arcuate foramen in the posterior arch of the atlas, an anatomical variant occurring in 3 to 15% of the population. It was hypothesized that the presence of the arcuate foramen might cause tethering of the vertebral artery and lead to its dissection by repetitive trauma. Lateral plain films of the cervical spine in cases of posterior circulation stroke were taken. Eight of 11 patients showed aberrant arcuate foramina. Of the remaining three patients, one had normal cervical spine X-rays, one had an absent right posterior arch of the atlas following previous surgery for a cervical meningocele, and one patient had incomplete ossification of the vertebrae. Seven of the nine patients with arcuate foramina had vertebral angiograms. In all cases this showed the vertebral artery passing through the arcuate foramen before entering the brain and an appearance consistent with arterial dissection and occlusion at the same site below the foramen. Most documented cases of posterior circulation stroke in children follow trauma, which may be minimal or repetitive, with thrombotic occlusion of the artery at C1-C2 level. The association with an arcuate foramen and its possible causative role in the genesis of posterior circulation stroke in children has not been previously recognized. There may be a causal association between the presence of an arcuate foramen, tethering of the vertebral artery in the foramen, and dissection from repetitive trauma with movement of the neck.  相似文献   
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