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排序方式: 共有851条查询结果,搜索用时 15 毫秒
61.
BACKGROUND: Acute bacterial rhinosinusitis (ABRS) is a common illness that is routinely managed by physicians from several different specialties. However, the actual diagnostic and treatment preferences of physicians from these different specialties are not known. OBJECTIVE: To determine whether the radiographic evaluation and management of community-acquired ABRS differs according to medical specialty. DESIGN, SETTING, AND PARTICIPANTS: Randomized survey of 450 board-certified physicians in the United States from family medicine, general internal medicine, and otolaryngology. MAIN OUTCOME MEASURES: Responding physicians' use of diagnostic radiography as well as choice and duration of antimicrobial and adjunctive treatments of ABRS. RESULTS: Otolaryngologists were more likely to use supportive diagnostic radiography (P =.04). They were also more likely to treat patients with adjunctive therapy, such as topical decongestants (P =.01), guaifenesin (P =.01), and saline nasal irrigation (P =.01), in addition to antibiotics. Otolaryngologists prescribed more medications to treat patients with ABRS than primary care physicians (P =.01). There were no significant differences in diagnosis and management by family physicians and general internists. CONCLUSIONS: Otolaryngologists use more health care resources to diagnose and treat ABRS than primary care physicians despite an absence of evidence that such tests and treatments lead to better outcomes. Otolaryngologists typically treat a patient population with a higher prevalence of ABRS and frequently see referred patients with recurrent acute sinusitis and chronic rhinosinusitis, which may explain their tendency to treat patients more aggressively. Nevertheless, these survey results illustrate a lack of consensus within the medical community regarding the evaluation and management of community-acquired ABRS, suggesting that widely accepted evidence-based practice guidelines need to be developed. 相似文献
62.
Yagmurlu B Ozcan H Aytaç SK Bilgiç S Sanlidilek U 《Journal of clinical ultrasound : JCU》2002,30(2):109-113
We report a case in which an intrarenal arteriovenous fistula caused the nutcracker effect. Color Doppler sonography of the left renal artery showed a peak systolic velocity of 150 cm/second and renoaortic ratio of 2.1. The left renal vein was significantly dilated, and the adjacent renal artery was kinked. A stenosis in the left renal vein at the aorto-mesenteric bifurcation was demonstrated, with a maximum velocity of 201 cm/second. Renal Doppler evaluation showed an area of high-velocity, low-resistance arterial flow consistent with an arteriovenous fistula in the inferior half of the left kidney. Angiography confirmed the fistula. The fistula was successfully occluded by coil embolization. Follow-up sonography showed almost complete obliteration of the fistula, regression of the renal vein dilatation, and a reduction in renal venous and arterial flow velocities. Given the reversibility of the fistula's effects, we suggest the term "pseudonutcracker effect" to describe this case. 相似文献
63.
Sadik S Taskin O Sehirali S Mendilcioglu I Onoğlu AS Kursun S Wheeler JM 《Human reproduction (Oxford, England)》2002,17(5):1343-1344
Various classifications have been used for congenital anomalies of the Müllerian system. We report a case of a previously unknown anomaly of the uterus, and propose its possible embryological causes. The patient presented with primary amenorrhoea and infertility, and during laparoscopy three distinct uterine horns were observed. The tubes were connected to the two most lateral horns, each juxtaposed to a normal ovary. The middle horn had a seemingly normal attachment to the right uterosacral ligament, whereas its attachment to the left uterosacral ligament appeared attenuated and less normal. Furthermore, the right horn was immediately attached to the middle horn, whereas the left horn was, like its ipsilateral uterosacral ligament, attached to the middle horn by a more attenuated, stretched fibrous bridge. Only the middle horn, with its uterosacral ligaments, had an attached, although obstructed, cervix. Ultrasonographic examination revealed no endometrium echogeneity in any of these uterine bulbs. No etiologic factors were noted in the patient's history; her mother denied known ingestion of estrogens or other drugs while carrying her daughter. The pathogenesis of this anomaly cannot be clearly defined, but may involve sequential embryological errors of duplication of the Müllerian tracts, failure of fusion of each set of the Müllerian tracts with expected failed canalization of each tract and, finally, agenesis of the medial horn of the left duplicated tracts. 相似文献
64.
Risk and Outcome of Bowel Resection in Patients with Incarcerated Groin Hernias: Retrospective Study 总被引:1,自引:1,他引:0
The goal of this retrospective study was to evaluate factors that increase the risk of bowel necrosis and document the outcome of bowel resection in patients with strangulated hernias. We identified 102 patients (60 men, 42 women) who underwent surgical treatment for an incarcerated hernia at the Kartal Education and Research Hospital Emergency Unit between April 1997 and April 2001. Patients in group 1 required intestinal resection (n = 16), and patients in group 2 did not (n = 86). The median age of the patients was 53 years (range 3–96). Demographic and surgical data were obtained from the patients charts and compared between the two groups. Women required bowel resections more often than men (p < 0.05). Patients older than 65 years and those with femoral or epigastric hernias required resection more often than patients younger than 65 years and those with inguinal, umbilical, or incisional hernias (p < 0.05 for all). Group 1 patients had a longer hospitalization and experienced more overall complications and wound infections than group 2 (p < 0.05 for all). In conclusion, incarcerated hernias are more common in men, but intestinal resection is required more often in women. The risk of intestinal resection is higher for patients with femoral hernias and those older than 65 years. Patients who undergo intestinal resection have a higher overall complication rate related to wound infections but not an increased risk of other complications or mortality.This study was presented at the 5th European Congress of Trauma and Emergency Surgery, Istanbul, Turkey, October 2002. 相似文献
65.
Bedirli A Gokahmetoglu S Sakrak O Ersoz N Ayangil D Esin H 《American journal of surgery》2003,185(4):339-343
BACKGROUND: To investigate the effects of beta-glucan on intraabdominal abscess and adhesion formation after ileocolic anastomosis in a rat bacterial peritonitis model. METHODS: Sixty male Wistar rats were used in this study. Bacterial peritonitis was induced by performing a cecal ligation and puncture (CLP). On the first day, abdomen was reopened and peritoneal fluid samples were taken for microbiological examination. Thereafter, cecum was resected and ileocolic anastomosis was made. Group 1 rats were given 1 mL of normal saline as a placebo. Group 2 and group 3 rats were given beta-D-glucan 2 mg/kg by intramuscularly; 1 mg of beta-1,3-D-glucanase was administered to group 3 rats just after the use of beta-D-glucan. Half of each group were killed at day 7 and at day 21, respectively. Adhesions were scored and the presence of intraabdominal abscesses was noted. RESULTS: One day after CLP, microbiological examination showed polymicrobial bacterial peritonitis. Five (8%) of the 60 animals died owing to sepsis. One week after CLP, in two rats in each group developed abscess formation. Three weeks after CLP, abscess formation was observed in only one rat in each group. The rats treated with the beta-glucan had significantly lower adhesion scores than did the saline-treated rats (P = 0.008 at one week; P = 0.001 at 3 weeks). Administration of beta-glucanase inhibited beta-glucan activity and resulted in more adhesions (P = 0.022 at 1 week; P = 0.006 at 3 weeks). CONCLUSIONS: Although the use of beta-glucan after ileocolic anastomosis in rats with experimentally developed intraabdominal sepsis does not have any significantly effect on mortality and abscess formation, beta-glucan is capable of reducing the frequency of adhesion. This effect of beta-glucan has been prevented with beta-glucanase 相似文献
66.
We have recently reported that flavonoids of cocoa inhibit the mammalian 15-lipoxygenase-1-a catalyst of enzymatic lipid peroxidation. To elucidate the structure-activity relationship of the inhibitory effect, we investigated the effects of 18 selected flavonoids of variable structure on pure rabbit reticulocyte and soybean 15-lipoxygenases using linoleic acid as substrate. Moreover, the inhibition by quercetin was studied in detail to gain insight into the mode of action. Quercetin was found to modulate the time-course of the reaction of both lipoxygenases by three distinct effects: (i) prolongation of the lag period, (ii) rapid decrease in the initial rate after the lag phase was overcome, (iii) time-dependent inactivation of the enzyme during reaction but not in the absence of substrate. A comparison of the IC(50) for the rapid inhibition of rabbit reticulocyte 15-lipoxygenase-1 revealed that (i) the presence of a hydroxyl group in the flavonoid molecule is not essential, (ii) a catechol arrangement reinforces the inhibitory effect, (iii) in the presence of a catechol arrangement the inhibitory potency inversely correlates with the number of hydroxyl groups, (iv) a 2,3-double bond in the C ring strengthens the inhibitory effect. The flavone luteolin turned out to be the most potent inhibitor of the mammalian enzyme with an IC(50) of 0.6 microM followed by baicalein (1 microM) and fisetin (1.5 microM). 相似文献
67.
68.
Nève V de la Roque ED Leclerc F Leteurtre S Dorkenoo A Sadik A Cremer R Logier R 《American journal of respiratory and critical care medicine》2000,162(1):139-147
We applied to 20 paralyzed ventilated children (0.15 to 14.3 yr, six with acute respiratory distress syndrome [ARDS]) the low-flow inflation (LFI) technique providing quasi-static volume-pressure (V-P) curves and compared the assessment of overdistension (OD) on dynamic and LFI (reference) inspiratory V-P curves. Dynamic curves were obtained at the airway opening during regular constant flow ventilation (Servo 300). Then LFI curves were obtained. Two analyses were performed: First, the nonlinear coefficient c of a second order polynomial equation (SOPE) fitted to dynamic data obtained during constant flow was compared with the c of SOPE fitted to LFI curve (within tidal volume [VT]). Second, the dynamic C20/C (ratio of compliance of the last 20% of the curve (C20) to total compliance [C]) was compared with the determination of the upper inflection point (UIP) on the LFI curve. OD was defined as a negative value of c, a C20/C < 0.80, an UIP included within the VT range for that child during regular ventilation. Using LFI V-P curves as reference, SOPE offered a better detection of OD than dynamic C20/C or the determination of the UIP by graphical means. Indeed the first analysis showed a substantial agreement (kappa 0.75) between dynamic c and LFI c detection of OD whereas the second analysis showed a poor agreement (kappa 0.22) between C20/ C and LFI detection of the UIP. In conclusion, quasi-static V-P curves can easily be obtained in children with the LFI technique. SOPE offers a good detection of OD on dynamic and LFI V-P curves but the C20/C index seems to be an inadequate measure of OD. 相似文献
69.
70.
S Ersoz S Ozbas O Basaran M Pehlivan S Hazinedaroglu E Anadol 《VASA. Zeitschrift für Gef?sskrankheiten》1999,28(2):127-129
Aneurysms of the coeliac axis are rare. Up to 1997, 137 cases had been reported. Here we present a coeliac aneurysm which involved the origin of the splenic, left gastric, and common hepatic arteries. After making a midline incision, infra-diaphragmatic control of the aorta was obtained. The aorta was clamped for 25 minutes to resect the aneurysm. The defect at the origin of the coeliac axis was closed with 1.5 cm PTFE patch. The distal segments of the splenic and left gastric arteries were ligated. A 6-mm ringed PTFE graft was interposed between the infra-renal aorta and the proper hepatic artery. The control arteriogram showed a good arterial flow. The patient recovered uneventfully after surgery with normalisation of hepatic function. 相似文献