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91.
Background Negative surgical margins minimize the risk of local recurrence after breast-conserving surgery. Intraoperative frozen section
analysis (FSA) is one method for margin evaluation. We retrospectively analyzed records of patients who received breast-conserving
therapy with intraoperative FSA of the lumpectomy cavity to assess re-excision rates and local control.
Methods Records were retrospectively reviewed for individuals who underwent breast-conserving surgery for ductal carcinoma in situ
(DCIS) or invasive carcinoma between 1993 and 2003. Inclusion criteria were a minimum of 2 years follow-up and intact tumor
at the time of operation. The major outcome measure was local recurrence. The Kaplan-Meier test was used to evaluate local
recurrence rates between groups.
Results 290 subjects with an average age of 57.2 years (range 27–89) underwent 292 lumpectomies with FSA. 11.3% had DCIS, 73.3% had
infiltrating ductal, 5.8% had infiltrating lobular, and 9.6% exhibited other forms of invasive carcinoma. 70 subjects underwent
additional resection at the time of breast surgery, 16 underwent subsequent re-excision, and 17 underwent subsequent mastectomy.
At a median follow-up of 53.4 months (range 5.8–137.8), there were six local recurrences (2.74%) in patients who had breast-conserving
procedures and two local recurrences in patients who underwent mastectomy. There were no statistically significant associations
among local recurrence rate, tumor size, nodal status, or overall stage. Local recurrences were higher in patients with DCIS
compared with invasive carcinoma, and tumors >2cm.
Conclusions Intraoperative FSA allows resection of suspicious or positive margins at the time of lumpectomy and results in low rates of
local recurrence and re-excision. The low local recurrence rate reported here is comparable to those reported with other margin
assessment techniques. 相似文献
92.
Thomas-Martin Wallasch Hartmut Göbel 《Cephalalgia : an international journal of headache》1993,13(1):11-14
Exteroceptive suppression of temporalis muscle activity was proposed by Schoenen and co-workers in 1987 as a tool in headache diagnosis and research. Their finding of a decreased or abolished second silent period (ES2) in chronic tension-type headache sufferers has been confirmed by several independent laboratories during the last five years. Temporalis silent periods have also been studied in various other types of headaches. Their modulation by neuropsychological factors and pharmacological agents has also been investigated as well as their retest reliability. The pathophysiological concept of muscle contraction in tension-type headache has been challenged by studies using temporalis silent periods. The exterocepfive suppression of temporalis muscle activity points unequivocally towards a central pathogenetic mechanism, although it remains unclear whether the abnormalities of temporalis ES2 represent the primary dysfunction or a secondary phenomenon in chronic tension-type headache. 相似文献
93.
94.
Krimer LS; Hyde TM; Herman MM; Saunders RC 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):722-731
The entorhinal cortex (ERC) has been implicated in the pathophysiology of
Alzheimer's disease, schizophrenia and other disorders affecting cognitive
functions. While powerful anatomical and histochemical methods
(immunohistochemistry, in situ hybridization, etc.) may be applied
(although with limitations) to postmortem human brain, each analysis should
utilize a cytoarchitectonic approach to provide appropriate comparisons
within the subdivisions of the ERC. Accordingly, we describe here the
normal cyto- and myeloarchitecture of the human ERC as a prerequisite for
the accompanying study of this region in schizophrenia. Our parcellation of
this cortex differs from previous treatments in three ways. First, we
adopted specific criteria of inclusion to define each subdivision of the
region. Although distinctive ERC features are most prominent in the
intermediate portion of this region, at least one of these features was
considered the minimum necessary criterion to include adjacent tissue in
the entorhinal area. Second, we used morphometric measurements (neuronal
size and density as well as subdivisional volume and laminar thickness) to
support our qualitative evaluation. Third, we have applied to the human ERC
the conventional cytoarchitectonic nomenclature of the entorhinal cortex
used previously in studies of non-human primates. This allows a more
accurate extrapolation of the available numerous experimental anatomical,
physiological and psychological data on this region to the human. As in the
monkey, the five main subareas were recognized in the human (prorhinal,
lateral, intermediate, sulcal and medial) but three required further
subdivision (intermediate, sulcal and medial). The morphometric results
obtained suggested a progression of the human entorhinal cortex from the
peripheral to the central subareas, with the intermediate subarea (281) as
the most complete entorhinal subdivision. Compared with non-human primates,
the human ERC not only retains the basic periallocortical organization but
also demonstrates further evolution. Taken together with available
experimental data on the connectivity of this brain region, these results
provide an anatomical basis for evaluating the ERC in human behavior.
相似文献
95.
96.
Control of insulin secretion by sulfonylureas, meglitinide and diazoxide in relation to their binding to the sulfonylurea receptor in pancreatic islets 总被引:12,自引:0,他引:12
U Panten J Burgfeld F Goerke M Rennicke M Schwanstecher A Wallasch B J Zünkler S Lenzen 《Biochemical pharmacology》1989,38(8):1217-1229
Sulfonylureas inhibit an ATP-dependent K+ channel in the B-cell plasma membrane and thereby initiate insulin release. Diazoxide opens this channel and inhibits insulin release. In mouse pancreatic islets, we have explored whether other targets for these drugs must be postulated to explain their hypo- or hyperglycaemic properties. At non-saturating drug concentrations the rates of increase in insulin secretion declined in the order tolbutamide = meglitinide greater than glipizide greater than glibenclamide. The same rank order was observed when comparing the rates of disappearance of insulin-releasing and K+ channel-blocking effects. The different kinetics of response depend on the lipid solubility of the drugs, which controls their penetration into the intracellular space. Allowing for the different kinetics, the same maximum secretory rates were caused by saturating concentrations of tolbutamide, meglitinide, glipizide and glibenclamide. A close correlation between insulin-releasing and K+ channel-blocking potencies of these drugs was observed. The relative potencies of tolbutamide, meglitinide, glipizide and glibenclamide corresponded well to their relative affinities for binding to islet-cell membranes, suggesting that the binding site represents the sulfonylurea receptor. The biphasic time-course of dissociation of glibenclamide binding indicates a complex receptor-drug interaction. For diazoxide there was no correlation between affinity of binding to the sulfonylurea receptor and potency of inhibition of insulin secretion. Thus, opening or closing of the ATP-dependent K+ channel by diazoxide or sulfonylureas, respectively, appears to be due to interaction with different binding sites in the B-cell plasma membrane. The free concentrations of tolbutamide, glipizide, glibenclamide and diazoxide which are effective on B-cells are in the range of therapeutic plasma concentrations of the free drugs. It is concluded that the hypo- and hyperglycaemic effects of these drugs result from changing the permeability of the ATP-dependent K+ channel in the B-cell plasma membrane. 相似文献
97.
98.
99.
U. Panten M. Schwanstecher A. Wallasch S. Lenzen 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(4):459-462
Summary Isolated pancreatic islets from mice were perifused with media containing maximally effective concentrations of glibenclamide (0.1–10 mol/l) or glipizide (1 mol/l). In these islets an increase of the glucose concentration from 10 mmol/l to 40 mmol/l or addition of d-glyc-eraldehyde (20 mmol/1) caused a temporary decrease in insulin release which was followed by a sustained enhancement of release. -Ketoisocaproate (3 or 20 mmol/1) did not inhibit insulin release; at high concentration it was an even stronger secretagogue than d-glucose or d-glyceraldehyde. It is concluded that high energy phosphates couple B-cell fuel metabolism and insulin release by acting both on the ATP-dependent K+ channel and on other targets not yet identified.Some of the results described here are part of the medical thesis of A. WallaschSend offprint requests to U. Panten at the above address 相似文献
100.