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71.
Nishit J. Shah Mukul Navnit Chandrashekhar E. Deopujari Shraddha S. Mukerji 《Indian journal of otolaryngology and head and neck surgery》2004,56(1):71-78
Endonasal endoscopic surgery is now the preferred technique to tackle pituitary tumours. Our paper describes the stepwise
endoscopic approach for surgeons embarking on pituitary surgery. It also highlights the common pitfalls encountered during
surgery and the ways to avoid them. One must proceed in a gradual step- wise manner starting from simple exposure of the sphenoid
sinus to complete endoscopic tumour removal so us to gain the neurosurgeon’s confidence as well as develop our own skills,
confidence and ability to tackle complications. We use the endonasal paraseptal trans- sphenoidal approach. Surgery begins
with gentle packing between the middle turbinate and septum to expose the anterior sphenoid wall and expose the sphenoid astium.
The ostitum is then widened inferiorly and onto the opposite side to expose both sphenoid sinuses. The inter- sphenoid sinus
and necessary mucosa is removed to expose the sella. We then use a bone flap technique or punches to open the sella. After
incising the dura, tumour is removed with a suction curette. An endoscope holder facilitates the operation. The bone flap
is replaced at the end of surgery to reconstruct the sella. This is especially important if a CSF leak is present. Nasal packing
is usually not required. 相似文献
72.
INTRODUCTION: Controversy around sub-specialisation in a district general hospital (DGH) has been ongoing for years. AIM: To study the effect of colorectal sub-specialisation on general surgical cases. METHODS: A retrospective audit between October 2002 and September 2003, including all referrals to the outpatient clinics of a single consultant surgeon in a DGH. RESULTS: 1,055 patients were seen in outpatient clinics, of which 53% (563) were seen in rapid access colorectal clinics. Overall, 87% (914) of patients were diagnosed to have colorectal pathology. The majority of the colorectal cases were referred using the designated referral forms. There were 427 urgent, 162 soon and 325 routine referrals with colorectal pathology, and 35 urgent, 22 soon and 84 routine referrals with non-colorectal pathology. Median waiting times for urgent, soon and routine referrals were 12, 61 and 91 days, respectively, for patients with colorectal pathology, in comparison with 44, 75 and 397 days for non-colorectal pathology. CONCLUSION: This audit confirms that colorectal sub-specialisation has resulted in a significant delay in the management of patients with non-colorectal diseases. This has major implications within a DGH setting. 相似文献
73.
Yang-Sheng Tzeng Eric Hoffman Janice Cook-Granroth Rie Maurer Niral Shah Joey Mansour Juerg Tschirren Mitchell Albert 《Magnetic resonance in medicine》2007,58(3):636-642
An anthropomorphic airway tree phantom was imaged with both hyperpolarized (HP) 3He MRI using a dynamic projection scan and computed tomography (CT). Airway diameter measurements from the HP 3He MR images obtained using a newly developed model-based algorithm were compared against their corresponding CT values quantified with a well-established method. Of the 45 airway segments that could be evaluated with CT, only 14 airway segments (31%) could be evaluated using HP 3He MRI. No airway segments smaller than approximately 4 mm in diameter and distal to the fourth generation were adequate for analysis in MRI. For the 14 airway segments measured, only two airway segments yielded a non-equivalent comparison between the two imaging modalities, while eight more had inconclusive comparison results, leaving only four airway segments (29%) that satisfied the designed equivalence criteria. Some of the potential problems in airway diameter quantification described in the formulation of the model-based algorithm were observed in this study. These results suggest that dynamic projection HP 3He MRI may have limited utility for measuring airway segment diameters, particularly those of the central airways. 相似文献
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BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI. 相似文献
78.
Van Buskirk Glenn A. González Mario A. Shah Vinod P. Barnhardt Scott Barrett Colin Berge Stephen Cleary Gary Chan Keith Flynn Gordon Foster Thomas Gale Robert Garrison Raymond Gochnour Scott Gotto Amanda Govil Sharad Gray Vivian A. Hammar James Harder Samuel Hoiberg Charles Hussain Ajaz Karp Carol Llanos Hector Mantelle Juan Noonan Patrick Swanson David Zerbe Horst 《Pharmaceutical research》1997,14(7):848-852
Pharmaceutical Research - 相似文献
79.
80.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
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