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21.
Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed.  相似文献   
22.
Background: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied. Objective: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats. Methods: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic–acrylic chamber and air sampler. Results: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change ±SD: washing; 487.6 ± 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 ± 871.6 mU per 30 minutes, p = 0.46 acepromazine; −620.6 ± 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72). Conclusions: Our data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats. (J ALLERGY CLIN IMMUNOL 1995;95:1164-71.)  相似文献   
23.
Adhesion formation is a major source of postoperative morbidity and mortality. In this study, the ability of a variety of lazaroid formulations [the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p. adhesion formation in three rabbit models was examined. In initial studies, PNU83836E was administered via Alzet miniosmotic pump to the site of injury. In the sidewall and double uterine horn models, PNU83,836E was administered via Alzet miniosmotic pump for the entire postoperative interval. In the sidewall model, there was a dose- dependent reduction in the area of the sidewall injury that was involved in adhesions. In the double uterine horn model, PNU83,836E was administered via Alzet miniosmotic pump to the area of injury for 1, 2, 3 or 7 days. Administration for as little as 24 h after surgery significantly reduced the extent of adhesion formation and the reduction was increased if it was administered for longer. Further studies were conducted in which various lazaroid formulations were administered as a bolus at the end of surgery. In both the sidewall and double uterine horn models, administration of either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or lipid emulsion vehicles) at the end of surgery reduced adhesion formation. Administration of a bolus of PNU74006F 10 min prior to initiation of surgery with or without additional treatment at the end of surgery further increased its efficacy in the reduction of adhesion formation. Administration of a minimum of 1.5 mg before and after surgery (3 mg total) was required for maximal efficacy. These studies demonstrate that pre- and postoperative administration of either a steroidal (PNU74006F) or non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation and reformation of postoperative adhesions in three animal models.   相似文献   
24.
25.
Calcitonin gene-related peptide (CGRP) has been immunohistochemically co-localized with substance P (SP) in capsaicin-sensitive, varicose axons supplying the skin, viscera and cardiovascular system of the guinea pig. After treatment with colchicine in vitro, 82% of SP neurons in the dorsal root ganglia contained CGRP-like immunoreactivity while 96% of CGRP neurons were immunoreactive for SP. Both CGRP- and SP-like immunoreactive material are transported peripherally and centrally from dorsal root ganglia. Thus, in tissues such as the gut where there are intrinsic nerves containing SP but lacking CGRP, CGRP-like immunoreactivity is a useful means of specifically labelling axons of most sensory neurons containing SP.  相似文献   
26.
Atypical femur fractures (AFF) are a rare but serious complication of long-term bisphosphonate use. Although clearly defined by ASBMR criteria, a proportion of patients with AFFs may go unrecognized and the use of qualitative fracture criteria may lead to uncertainty in AFF diagnosis, with significant therapeutic implications. A score that rapidly and accurately identifies AFFs among subtrochanteric femur fractures using quantitative, measurable parameters is needed. In a retrospective cohort of 110 female patients presenting with AFFs or typical femur fractures (TFFs), multiple logistic regression and decision tree analysis were used to develop the Sydney AFF score. This score, based on demographic and femoral geometry variables, uses three dichotomized independent predictors and adds one point for each: (age ≤80 years) + (femoral neck width <37 mm) + (lateral cortical width at lesser trochanter ≥5 mm), (score, 0 to 3). In an independent validation set of 53 female patients at a different centre in Sydney, a score ≥2 demonstrated 73.3% sensitivity and 69.6% specificity for AFF (area under the receiver-operating characteristic curve [AUC] 0.775, SE 0.063) and remained independently associated with AFF after adjustment for bisphosphonate use. The Sydney AFF score provides a quantitative means of flagging female patients with atraumatic femur fractures who have sustained an AFF as opposed to a TFF. This distinction has clear management implications and may augment current ASBMR diagnostic criteria. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
27.
Prospective trials demonstrate that sentinel node (SN) biopsy after neo-adjuvant chemotherapy (NACT) has a significant false-negative rate (FNR) when only 1 or 2 SNs are removed. It is unknown whether this increased FNR correlates with an elevated risk of recurrence. Tumor Registry data at an NCI-Designated Comprehensive Cancer Center were reviewed from 2004 to 2018 for patients having a negative SN biopsy after NACT. Among 190 patients with histologically negative nodes after NACT having 1 (n = 42), 2 (n = 46), and ≥3 (n = 102) SNs, axillary recurrences occurred in 7.14%, 0%, and 1.96% (p = 0.09), breast recurrences occurred in 2.38%, 6.52%, and 0.98% (p = 0.12), and distance recurrences occurred in 16.67%, 8.70%, and 7.84% (p = 0.27), respectively. Time to first recurrence did not differ by SN count (p = 0.41). After adjustment for age, race, clinical stage, and receptor status, there were no differences in the rates of axillary (p = 0.26), breast (p = 0.44), or distance recurrence (p = 0.24) by numbers of SNs harvested. Median follow-up was 46.8 months. Despite higher post-NACT FNRs reported in randomized trials for patients having <3 sentinel nodes, recurrence rates were not significantly different for 1 versus 2 versus ≥3 SNs. This suggests that patients having 1 or 2 post-NACT SNs identified may not necessitate axillary dissection.  相似文献   
28.
29.
The purpose of this study was to characterize presenting imaging findings in women younger than 40 diagnosed with invasive breast cancer in the context of pathology and clinical course. Retrospective chart and imaging reviews were performed in patients under 40 diagnosed with breast cancer between July 1, 2004, and December 31, 2013. Patient demographic, imaging, pathology, and clinical data were collected. Overall and recurrence-free survival were estimated using the Kaplan-Meier method. Univariate Cox proportional hazards models were performed to identify factors associated with recurrence-free survival. Our study cohort consisted of 110 patients with invasive mammary carcinoma. One hundred one (91.8%) presented with a palpable mass. The mean size of all lesions on imaging was 3.5 cm ± 2.9 cm. Malignant calcifications were present in 54 (49.1%) cases. Imaging demonstrated multifocal or multicentric disease in 45 (40.9%) cases. Seventy four (67.3%) cancers were high grade. Luminal genomic subtypes were the most common (n = 61, 55.5%). At presentation, 4 (3.6%) patients had bilateral malignancy and 8 (7.3%) patients had distant metastatic disease. Ninety seven (88.2%) underwent neoadjuvant chemotherapy and 67 (60.9%) underwent radiation therapy. Seventy five (68.2%) of the patients underwent mastectomy. The restricted mean time to recurrence was 9.01 years (standard error 3.162 months). ER positivity was associated with compromised recurrence-free survival. The overall survival rate was 0.962 at 10 years. Young patients diagnosed with breast cancer typically present with advanced breast imaging findings and undergo aggressive treatment. Recurrence often occurs >5 years from diagnosis, and ER positive subtypes are at increased risk for recurrence.  相似文献   
30.
Objective: Our purpose was to determine whether primary and preventive care is practiced by a university obstetrician-gynecologist group practice.Study design: A retrospective chart review spanning 2 years of four academic physicians' private practices was performed. A total of 335 patients were reviewed with 739 patient encounters and 1032 patient problems identified. The definition of a primary care physician according to The American College of Obstetricians and Gynecologists was used to standardize data collection and evaluation.Results: Obstetric complaints accounted for 27.7% of all visits, whereas 65.4% were for gynecologic problems. Almost 7% of all complaints were neither obstetric nor gynecologic, and of those 74.6% were primary care problems completely managed by the obstetrician-gynecologist. Only 19.7% of these were referred for management. More than 89% of all encounters () involved some element of primary care.Conclusion: This study provides evidence that the majority of health care provided by the obstetrician-gynecologists is primary care.  相似文献   
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