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排序方式: 共有8143条查询结果,搜索用时 15 毫秒
61.
0 引言 胰腺多房性潴留性囊肿极为罕见,我科收治1例,报道如下.1 病例报告 患者,男,29岁,因发现右上腹包块11d入院,缘于11d前无明显诱因感右上腹痛,仅局限于右上腹部,无肩背部放散痛,伴间歇性发热,体温最高达38.3℃,经抗炎,对症治疗无效.并逐渐可触及右上腹有一肿块,在当地医院行穿刺检查为脓血性液体.镜检发现炎性细胞,B超示:胆囊窝下方及右肾内侧及腹腔动脉,下腔静脉外前方可见异常区,大小约9.1cm×6.6cm×7.6cm,边界清楚,形态不规则,内呈蜂窝状,可见多个大小不等的液性暗区,CT示:右上腹部上腔静脉前方6.0cm×9.0cm肿块和周围组织粘… 相似文献
62.
Epothilone A, a novel macrolide antibiotic, is produced by the myxobacterium Sorangium cellulosum. Similarly to paclitaxel (Taxol), epothilone A inhibits cell proliferation and induces apoptosis by binding to tubulin and stabilizing of microtubuli. Like paclitaxel, epothilone A induced apoptosis in neuroblastoma cells which exhibit constitutive cytoplasmic sequestration of p53 and, hence, an impaired DNA-damage-dependent apoptosis. However, in contrast to paclitaxel, epothilone A was also effective against a constitutively Pgp-expressing, multidrug resistant neuroblastoma cell line (SK-N-SH). Moreover, the efficacy of epothilone A was not impaired even though the Pgp level was further increased during treatment with the drug. 相似文献
63.
Incidental cholecystectomy during colorectal surgery. 总被引:1,自引:0,他引:1
E S Juhasz B G Wolff A P Meagher R M Kluiber A L Weaver J A van Heerden 《Annals of surgery》1994,219(5):467-474
OBJECTIVE: To assess the risks and benefits of incidental cholecystectomy in patients having colorectal surgery. SUMMARY BACKGROUND DATA: Cholelithiasis is found commonly during abdominal surgery. Previous studies used disparate methods to assess the risks and benefits of incidental cholecystectomy and have reached contradictory conclusions. METHODS: All patients in whom asymptomatic cholelithiasis was noted during colorectal surgery between January 1982 and December 1986 were studied. Operative morbidity and long-term outcome were assessed by chart review and questionnaire. RESULTS: Three hundred five patients were identified, of whom 195 (63.9%) had an incidental cholecystectomy and 110 (36.1%) did not. The two groups were similar in terms of age, sex, primary disease, and associated medical conditions, although fewer emergency procedures, abdominoperineal resections, and Hartmann's procedures were needed in the cholecystectomy group. The overall operative morbidity rate was the same in both groups. The long-term risk for developing small bowel obstruction was also similar. After a median follow-up of 6 years after hospital discharge, biliary pain or cholecystitis developed in 16 patients (14.6%) in the "no cholecystectomy" group, 12 of whom have had cholecystectomy. Two additional patients had cholecystectomy for acute postoperative cholecystitis while still in the hospital. Six more patients have had incidental cholecystectomy at subsequent laparotomies. The cumulative probability of needing cholecystectomy at 2 and 5 years after the initial colorectal operation was 12.1% and 21.6%, respectively. CONCLUSIONS: Incidental cholecystectomy was not associated with increased postoperative morbidity, whereas the long-term risk that previously asymptomatic gallstones would become symptomatic was substantial. Unless there are clear contraindications, patients with asymptomatic gallstones who have colorectal surgery should have concomitant cholecystectomy. 相似文献
64.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition 相似文献
65.
Francisco Cano Angela Delucchi Eduardo Wolff Eugenio Rodriguez Angel Fuentes 《Pediatric nephrology (Berlin, Germany)》1995,9(5):606-608
A 6-month protocol of oral pulse calcitriol was used in nine uraemic children (2–14 years old) on dialysis who presented with renal osteodystrophy. Calcitriol was administered twice a week, 4 g per dose for patients over 30 kg and 3g for patients less than 30 kg. Plasma levels of parathyroid hormone, calcium, phosphorus and alkaline phosphatase were carefully controlled during the study. Parathyroid hormone levels decreased by 68% and 56% by the 2nd and 6th months of treatment in seven patients, while they remained unchanged in two patients with focal segmental glomerulosclerosis and massive proteinuria. Eight hypercalcaemic episodes from 77 determinations were observed, all of them recovered after 1 week of vitamin D withdrawal. We conclude that oral calcitriol pulse therapy is a good alternative for renal osteodystrophy in uraemic children. Careful monitoring of plasma parathyroid hormone and calcium is needed during follow-up when using this approach in paediatric patients. 相似文献
66.
Hatch M von Ehrenstein O Wolff M Meier K Geduld A Einhorn F 《Journal of women's health / the official publication of the Society for the Advancement of Women's Health Research》1999,8(2):269-277
The period during and after puberty seems to be important for breast cancer initiation. Because experiences during that time are likely to be influenced by a woman's cultural background, we conducted a pilot study among Hispanic and Caucasian women to elicit their memories of early life events. These data were used to design culture-specific questionnaire modules for the retrospective assessment of peripubertal breast cancer risk factors, using specific strategies to trigger accurate recall. Study subjects were volunteer breast cancer survivors or relatives of survivors. In carrying out this work, we took methods from the social sciences and applied them to a research question in chronic disease epidemiology. We found both qualitative and quantitative differences in recall of peripubertal exposures and experiences between Hispanic and Caucasian subjects. Our preliminary data indicate that in contrast to Caucasian women, Hispanic women consider the church rather than school a touchstone for recalling past events. Under the domain "body development," Hispanic women are more likely to mention menstruation than Caucasian women but less likely to recall changes in body hair and breast development. Caucasian women cited team sports as an important physical activity during the peripubertal period, whereas Hispanic women listed more sedentary games and housework as the main activities. Results of our pilot study support the view that to enhance the validity of retrospective data on peripubertal breast cancer risk factors, it is important to take account of cultural differences. Our experience using qualitative methods to elicit data of this kind in the context of a larger epidemiologic research effort suggests that such innovative approaches are valuable. 相似文献
67.
68.
p
< 0.05). On postoperative
days 3 and 7 the values were 7.2 (5.3–8.2) and 7.5 (5.4–9.4) mmol/L,
respectively, in the erythropoietin group compared to 6.7 (5.2–7.8)
and 6.9 (5.1–8.6) mmol/L in the placebo group (
p
<
0.01). At discharge the hemoglobin concentration was 7.8 (5.9–8.8)
mmol/L in the erythropoietin group and 7.2 (5.4–8.6) mmol/L in the
placebo group (
p
< 0.002). The blood loss during
operation was similar in the two groups. In the erythropoietin group
the median value was 280 ml (range 25–2000 ml), with the lower and
upper quartiles 150 and 500 ml, respectively. In the placebo group the
blood loss was median 300 ml (range 50–1800 ml), with the lower and
upper quartiles 200 and 750 ml, respectively. The number of blood
transfusions given was significantly lower in the erythropoietin group,
with a mean of 0.3 (range 0–6) units compared to 1.6 (0–9) units in
the control group (
p
< 0.05). In conclusion, the
hemoglobin concentration at the time of surgery and during the week
following surgery was significantly higher in the group of patients
receiving r-HuEPO perioperatively compared to the placebo group
together with a significant lower use of blood transfusions in the
r-HuEPO group. However, the clinical implications of these findings has
yet to be proven.RID=" ID=" <E5>Correspondence to:</E5> N. Qvist, M.D., D.Sci. 相似文献
69.
Rationale: Understanding the contribution of the various serotonin (5-HT) receptor subtypes to the behavioral effects of selective serotonin
reuptake inhibitors (SSRIs) may contribute to the discovery of increasingly effective drugs for the treatment of conditions
such as depression, panic and obsessive-compulsive disorders. Objectives: A drug discrimination procedure was used to determine whether the administration of an SSRI was associated with a specific
interoceptive stimulus cue and to what extent that cue was related to activation of the 5-HT1A receptor. Method: Pigeons were trained to discriminate 20 mg/kg of the short acting, SSRI, LY233708 dihydrochloride dihydrate [(–)-cis-1-(6-chloro-1,2,3,4-
tetrahydro-1-methyl-2-naphthalenyl)piperazine] from saline. Results: LY233708 induced a specific, dose-related stimulus cue. The SSRIs, fluoxetine and citalopram, induced dose-related responding
on the LY233708-associated key. In contrast, nisoxetine, a selective norepinephrine uptake inhibitor, induced responding on
the saline-associated key. The prototypical 5-HT1A agonist, 8-OH-DPAT [8-hydroxy-(2-di-n-propylamino)tetralin] substituted for LY233708. This generalization was blocked by the selective 5-HT1A antagonist, WAY-100635 [N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridinyl) cyclohexanecarboxamide]. Conclusion: These data demonstrate that an SSRI can induce a specific, stable discriminative stimulus that appears to involve activation
of the 5-HT1A receptor in the pigeon.
Received: 11 January 1999 / Final version: 7 May 1999 相似文献
70.
D L Allen P A Leiter R L Tielking W P Hoffman A N Vidyashankar R B van Lier R K Wolff 《Drug and chemical toxicology》1999,22(4):595-611
Information was needed on effects of possible occupational inhalation exposure to an M1-receptor agonist (xanomeline) such as might occur during the manufacturing process. Both acute and repeated inhalation exposures to xanomeline were carried out in six male rhesus monkeys using a head-dome exposure system. Exposure concentrations ranged from 0.3 to 10 mg/m3. The exposure durations were up to 2 weeks. Decreases in tidal volume and increases in respiratory frequency were both time and concentration related during acute exposures. These effects were blocked with atropine pre-treatment. Correlation with pulmonary resistance measurements in two monkeys suggested that these were bronchoconstrictive changes that increased with severity with time at a given concentration and with concentration when measured after a constant exposure time. The dose-response was relatively steep with 10 mg/m3 becoming intolerable to the monkeys after approximately 15 minutes, but no measurable effects were observed at 0.3 mg/m3 after up to 4 hours of exposure. To investigate the effects of repeated exposures, monkeys were exposed for 4 hr/day, 5 days/wk for 2 weeks to 0.0 (air only), 0.3, and 1.2 mg xanomeline/m3 of air. When compared to the air-only exposure, 0.3 mg/m3 caused no significant changes in tidal volume. In contrast, 1.2 mg/m3 caused a rapid and significant decrease in tidal volume that was sustained throughout the 4-hr exposure. A slower rise in breathing frequency also occurred. Repeated exposures did not alter the effects seen after a single exposure. It is concluded that xanomeline, a M1-receptor agonist, can acutely alter normal ventilation in non-human primates at airborne concentrations > or = 0.6 mg/m3 and should be carefully controlled in a manufacturing environment. The no-observed-effect concentration was 0.3 mg/m3. 相似文献