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排序方式: 共有802条查询结果,搜索用时 15 毫秒
61.
Many aspects of bladder cancer remain obscure under clinical conditions. The natural course of the illness is seldom known in human patients, in whom only the treated natural history is subject to investigation. Cancer research in animals can complement clinical investigations. The following experimental set-ups are of importance; chemically induced bladder cancer; transplantation of human urothelial carcinoma in immunodeficient nude mice (xenograft model); transplantation of clinically induced bladder cancer in syngenetic animals (syngenetic model). These models are used for tumour induction and the development of immunotherapy, chemotherapy and new techniques. The extrapolation of these experimental results to clinical situations is being discussed. Some experimental results are of interest for practising urologists, e.g. increased incidence of tumour development in dilated upper urinary tract or in the bowel segment after urinary diversion; new therapeutic approaches such as breakdown of multidrug resistance to chemotherapy or administration of photodynamic therapy; planning of intravesical therapy relating to aspects of cell proliferation. 相似文献
62.
63.
H. K. DÜRR CHRISTIANE BODE R. KRUPINSKI J. CH. BODE 《European journal of clinical investigation》1978,8(3):189-191
Macroamylasaemia was produced in vitro by incubation of hydroxyethylstarch with serum, and in vivo by intravenous infusion of hydroxyethylstarch. Gel filtration on Sephadex G-100 revealed distinct differences in molecular size distribution between such hydroxyethylstarch-induced macroamylase and the usual form of naturally occurring macroamylase which was observed in a few patients from our hospital. Further studies demonstrated that the gel filtration elution pattern of amylase activity in serum containing hydroxyethylstarch-induced macroamylase is significantly altered with time in vitro and in vivo, probably because of an enzymatic degradation of the hydroxyethylstarch components of the macromolecular complexes. In a healthy volunteer the serum amylase activity was elevated to a maximum of 797 u/l and the renal clearance rate of amylase was diminished to a minimum of 0.3 ml/min after infusion of 500 ml of a 6% solution of hydroxyethylstarch, as compared to 300 u/l, and 0.95 ml/min, respectively, during the pre-infusion period. 相似文献
64.
Valdecoxib does not impair platelet function 总被引:3,自引:0,他引:3
Leese PT Talwalker S Kent JD Recker DP 《The American journal of emergency medicine》2002,20(4):275-281
The platelet effects of a supratherapeutic dose of the new cyclooxygenase (COX)-2 specific inhibitor, valdecoxib (40 mg twice a day), naproxen 500 mg twice a day, diclofenac 75 mg twice a day, and placebo were compared in 62 healthy adult subjects in this 7(1/2) day single-center, randomized, placebo-controlled trial. Platelet aggregation responses (to arachidonate [AA], collagen, and adenosine diphosphate [ADP]), bleeding time, and serum thromboxane B(2) (TxB(2)) concentrations were measured at baseline and at regular intervals on days 1 and 8. Valdecoxib had no effect on platelet function. Naproxen and diclofenac significantly reduced the platelet aggregation response to AA and to a lesser extent collagen and ADP at most assessments compared with placebo. Naproxen significantly lowered serum TxB(2) levels. In contrast to standard doses of 2 nonsteroidal antiinflammatory drugs (NSAIDs), a supratherapeutic valdecoxib dosage does not impair platelet function (COX-1). Valdecoxib may be a safer analgesic option than conventional NSAIDs in patients for whom bleeding complications are a concern. (Am J Emerg Med 2002;20:275-281. 相似文献
65.
Familial hemiplegic migraine: a clinical comparison of families linked and unlinked to chromosome 19 总被引:5,自引:0,他引:5
GM Terwindt RA Ophoff J Haan RR Frants MD Ferrari for the DMGRG 《Cephalalgia : an international journal of headache》1996,16(3):153-155
We compared the clinical characteristics of 50 patients from three unrelated families with familial hemiplegic migraine (FHM) linked to chromosome 19, with those of 20 patients from two families with FHM not linked to chromosome 19. We found no significant differences for age at onset, frequency and duration of attacks, duration of the paresis, and occurrence of basilar migraine symptoms. In the linked families, significantly more patients reported unconsciousness during attacks (39%, vs 15%; p<0.05) and provocation of attacks by mild head trauma (70% vs 40%; p< 0.05). In one linked family patients also displayed chronic progressive cerebellar ataxia, whereas in one unlinked family benign infantile convulsions occurred in addition to FHM. Interestingly, so far an association with cerebellar ataxia was only described in chromosome 19-linked families. FHM linked to chromosome 19 and FHM unlinked to chromosome 19 do not differ with respect to clinical features. 相似文献
66.
This study employed the articulated thoughts in simulated situations (ATSS) paradigm in the investigation of college students' thoughts upon confrontation with a conspiracy to commit a sexual-orientation-based hate crime versus a nonbias crime. In a between-subjects experimental design, participants were exposed to an audiotaped scenario depicting either the planning of a hate crime or a comparable nonhate crime. Content analysis of participants' articulated thoughts in response to these stimuli revealed that the hate crime resulted in more intentions to physically aggress against the perpetrator. This supports the notion that hate crimes have a greater potential than other crimes to lead to future violence. More people were also willing to intervene and help the hate crime victim than the nonhate crime victim. In addition, antigay attitudes turned out to be predictive of anger against the hate crime victim, disapproval of the hate crime victim, and support of the hate crime perpetrators. Implications of these findings, as well as suggestions for future research, are discussed. 相似文献
67.
Prostate cancer is a mayor health care problem, especially in the industrialised countries of the Western world. At this time it is the second most common cancer reason for death (CH: 1500 men/year) which will even get more importance in the future by demographic developments. While there is no doubt that in individuals early detection of organ confined disease with localised treatment the prostate cancer can be eradicated and individual men be cured there are uncertainties whether mass screening a population will contribute to reducing prostate cancer related mortality. Its value has not been proved definitively by prospective randomised controlled studies. Most of Medical Societies recommend a "well informed" decision by family physicians, where the men between 50-70 years know about the benefits and harms including: risk of cancer, diagnostic procedures, therapeutic consequences and possible side effects. After agreement of early detection a biopsy has to be done directly above a PSA level of 4.0 ng/ml or a suspicious digital rectal examination. A PSA "grey zone" 4-10 ng/ml can not further be postulated. The ratio of free/total PSA gives no support to prolong biopsy in this moment, because an elevated benign prostate with a higher production of free PSA can mask the tumor in the peripheral zone. Results of the ERSPC and the PLCO trials are expected to give information about the benefits and harms of mass screening in 2006/8. 相似文献
68.
Red cell loss following orthopedic surgery: the case against postoperative blood salvage 总被引:3,自引:0,他引:3
J Umlas ; RR Foster ; SA Dalal ; SM O'Leary ; L Garcia ; MS Kruskall 《Transfusion》1994,34(5):402-406
BACKGROUND: Expensive devices have been developed for the collection and transfusion of blood salvaged after hip or knee arthroplasty. STUDY DESIGN AND METHODS: The volume of salvaged red cells was measured for the first 6 hours after operation. This volume was compared to total red cell loss during hospitalization and to the volume of allogeneic red cells transfused. RESULTS: Mean postoperative red cell loss in 31 patients following hip replacement was 55 +/− 29 mL and that in 20 patients following knee replacement was 121 +/− 50 mL. The 6-hour wound drainage represented 8.7 and 16.8 percent of overall red cell loss during hospitalization for hip and knee replacement, respectively. The transfusion of postoperatively salvaged red cells would have supplanted transfusion of less than one-third of a unit of allogenic blood after hip replacement and two-thirds of a unit after knee replacement. Only three patients (5.9%) lost red cell volume in the drainage equivalent to or in excess of 1 unit of red cells (180 mL). The volume of red cells salvaged postoperatively bore no relationship to perioperative red cell losses as a whole. CONCLUSION: The relatively small red cell loss in the postoperative period in most arthroplasty patients does not appear to justify the routine use of this technique for the recovery of autologous blood. 相似文献
69.
Male Wistar rats were trained to discriminate either the opioid receptor like (ORL)-1 receptor agonist Ro 64-6198 (1S,3aS-8-2,3,3a,4,5,6-hexahydro-1H-phenalen-1-yl-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-one) or morphine from saline using a two-choice, food reinforced, operant procedure. Acquisition of Ro 64-6198 discrimination was relatively slow (mean trials to criterion 113 +/- 6), and a final 4 mg/kg dose (initial training dose 2 mg/kg) was required to establish appropriate stimulus control. In comparison, a separate group of rats attained a morphine (2 mg/kg) discrimination in 44 +/- 4 trials. In tests of substitution, Ro 64-6198 produced a dose-related generalization to its own cue (ED(50) of 1.1 mg/kg i.p.), yet only weakly generalized to the morphine cue (19% at 10 mg/kg i.p.). In contrast, morphine generalized completely to the morphine cue (ED(50) of 0.7 mg/kg s.c.), yet only partially generalized to the Ro 64-6198 cue (40% at 6 mg/kg s.c.). The kappa opioid receptor agonist U50,488 [trans-3,4-dichloro-N-methyl-N(2-[1-pyrrolidinyl]cyclohexyl) benzeneacetamide methanesulfonate] (0.3-6 mg/kg s.c.) and the delta opioid receptor agonist SNC-80 [(+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide] (0.3-6 mg/kg i.p.) failed to evoke significant generalization to either cue. The mu opioid receptor agonists codeine (0.3-20 mg/kg) and buprenorphine (0.01-1 mg/kg) completely generalized to the morphine cue, but only buprenorphine partially generalized to the Ro 64-6198 cue. Naloxone pretreatment completely blocked the morphine cue (ED(50) of 0.005 mg/kg s.c.), yet only weakly attenuated the Ro 64-6198 cue at 0.3 mg/kg. Finally, the selective ORL-1 antagonist J-113397 [1-[(3R,4R)-1-cyclooctylmethyl-3-hydroxymethyl-4-piperidyl]-3-ethyl-1, 3-dihydro-2H-benzimidazol-2-one] completely blocked the Ro 64-6198 cue at a dose (30 mg/kg i.p.) that had no effect against the morphine cue. The present studies demonstrate that rats may be trained to discriminate Ro 64-6198 from saline, and the pharmacological characteristics of this cue are most consistent with ORL-1 receptor activation. 相似文献
70.
Lan‐Juan Zhao Xiao‐Gang Liu Yao‐Zhong Liu Yong‐Jun Liu Christopher J Papasian Bao‐Yong Sha Feng Pan Yan‐Fang Guo Liang Wang Han Yan Dong‐Hai Xiong Zi‐Hui Tang Tie‐Lin Yang Xiang‐Ding Chen Yan Guo Jian Li Hui Shen Feng Zhang Shu‐Feng Lei Robert R Recker Hong‐Wen Deng 《Journal of bone and mineral research》2010,25(2):320-329
Poor femoral neck bone geometry at the femur is an important risk factor for hip fracture. We conducted a genome‐wide association study (GWAS) of femoral neck bone geometry, examining approximately 379,000 eligible single‐nucleotide polymorphisms (SNPs) in 1000 Caucasians. A common genetic variant, rs7430431 in the receptor transporting protein 3 (RTP3) gene, was identified in strong association with the buckling ratio (BR, P = 1.6 × 10?7), an index of bone structural instability, and with femoral cortical thickness (CT, P = 1.9 × 10?6). The RTP3 gene is located in 3p21.31, a region that we found to be linked with CT (LOD = 2.19, P = 6.0 × 10?4) in 3998 individuals from 434 pedigrees. The replication analyses in 1488 independent Caucasians and 2118 Chinese confirmed the association of rs7430431 to BR and CT (combined P = 7.0 × 10?3 for BR and P = 1.4 × 10?2 for CT). In addition, 350 hip fracture patients and 350 healthy control individuals were genotyped to assess the association of the RTP3 gene with the risk of hip fracture. Significant association between a nearby common SNP, rs10514713 of the RTP3 gene, and hip fracture (P = 1.0 × 10?3) was found. Our observations suggest that RTP3 may be a novel candidate gene for femoral neck bone geometry. © 2010 American Society for Bone and Mineral Research 相似文献