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61.
Hall  FM; Storella  JM; Silverstone  DZ; Wyshak  G 《Radiology》1988,167(2):353-358
Carcinoma was found in 30% (119 of 400) of biopsy specimens obtained for mammographically suspicious but nonpalpable findings. The authors reviewed the mammograms of these 400 cases without knowledge of the biopsy results and placed each examination into one of four groups based on their suspicion for carcinoma: minimal (n = 82), slight (n = 91), moderate (n = 174), and high (n = 53). In 127 cases, mammograms showed either minimally suspicious calcifications (n = 33) or minimally (n = 49) or slightly (n = 45) suspicious masses. A 4.7% (six of 127) rate of carcinoma was found in these groups; five of the six cancers were in situ. Had follow-up mammography been done rather than biopsy for these 127 less suspicious lesions, it is probable that the delay in diagnosis would not have altered overall prognosis. In the remaining 273 patients, the positive predictive value of mammography for carcinoma would have risen from 30% (119 of 400) to 41% (113 of 273). The authors conclude that in the management of suspicious nonpalpable mammographic findings, the rate of carcinoma for lesions at biopsy can approximate 40%. This is almost double the rate of most published series.  相似文献   
62.
63.
5种解热镇痛药的胶束电动毛细管色谱分离研究   总被引:1,自引:0,他引:1  
陈勇  韩凤梅  袁倬斌 《药学学报》1996,31(8):637-640
报告了5种解热镇痛药——安替比林、4-氨基安替比林、安基比林、安乃近和保泰松的胶束电动毛细管色谱分离、紫外吸收检测法。研究了pH值、有机改性剂(甲醇)和十二烷基硫酸钠(SDS)浓度对分离的影响。在40mmol·L-1SDS—25mmol·L-1硼砂—15%甲醇(pH10.5)电泳介质中电泳,上述5组分可达基线分离。迁移时间批内和批间的RSD值分别小于1.3%和2.1%(n=5)。分离的理论塔板数在1.83×104~4.15×104之间。  相似文献   
64.
Introduction: Data on the mechanisms of sudden cardiac death are limited and may be biased by delays in rhythm recording and selection bias in survivors. As a result, the relative contributions of monomorphic ventricular tachycardia (VT) (cycle length [CL] > 260 ms), monomorphic fast VT (FVT) (CL ≤ 260 ms), and polymorphic VT (PMVT)/ventricular fibrillation (VF) have not been well characterized nor compared in patients with and without prior arrhythmic events. Methods: A retrospective cohort study of implantable cardioverter‐defibrillator (ICD) recipients with primary or secondary implant indications was used to evaluate intracardiac electrograms (EGMs) for the first spontaneous VT/VF resulting in appropriate ICD therapy. EGMs were categorized into VT, FVT, and PMVT/VF based on CL and morphologic criteria. Results: Of 616 implants, 145 patients (58 [40%] primary indications) received appropriate ICD therapy for VT/VF over mean follow‐up of 3.8 ± 3.2 years. Primary implants had more diabetes (28% vs 12%; P = 0.02) and less antiarrhythmic use (15% vs 33%; P = 0.02). In those patients with spontaneous arrhythmia, PMVT/VF occurred in 20.7% of primary versus 21.8% of secondary implants, FVT in 19.0% versus 21.8%, and VT in 60.3% versus 56.4%, respectively (P = 0.88). Spontaneous VT CL was similar regardless of implant indication (284 ± 56 [primary] vs 286 ± 67 ms [secondary]; P = 0.92). Conclusions: Monomorphic VT is the most common cause of appropriate ICD therapy regardless of implant indication. These results provide insight into the mechanisms of sudden cardiac death and have implications for the use of interventions designed to limit ICD shocks. (PACE 2011; 34:571–576)  相似文献   
65.
66.

Purpose

Based on previous studies that demonstrated the safety profile and preliminary clinical activity of prostate specific antigen (PSA) targeted therapeutic vaccines, as well as recent laboratory data supporting the value of the addition of co-stimulatory molecules B7-1, ICAM-1, and LFA-3 (designated TRICOM?) to these vaccines, we conducted a Phase I study to evaluate the safety and immunogenicity of a novel vaccinia and fowlpox vaccine incorporating the PSA gene sequence and TRICOM.

Methods

In this study, ten patients with androgen independent prostate cancer with or without metastatic disease were enrolled. Patients were treated with 2 × l08 pfu of a recombinant vaccinia virus vaccine (PROSTVAC-V) followed by 1 × 109 pfu of the booster recombinant fowlpox virus (PROSTVAC-F) both with gene sequences for PSA and TRICOM. The mean age of patients enrolled in the study was 70 (range 63 to 79). The mean PSA at baseline was 434 (range 9 – 1424).

Results

There were no deaths, and no Grade 3 or 4 adverse events. The most commonly reported adverse events, regardless of causality, were injection site reactions and fatigue. One serious adverse event (SAE) occurred that was unrelated to vaccine; this patient developed progressive disease with a new sphenoid metastasis. PSA was measured at week 4 and week 8. Four patients had stable disease (with less than 25% increase in PSA) through the week 8 study period. Anti-PSA antibodies were not induced with therapy: however, anti-vaccinia titers increased in all patients.

Conclusion

This study demonstrated that vaccination with PROSTVAC-V and PROSTVAC-F combined with TRICOM is well-tolerated and generated an immune response to vaccinia. Therefore, PROSTVAC-VF/TRICOM represents a feasible therapeutic approach for further phase II and III study in patients with prostate cancer.  相似文献   
67.

Objectives

To analyze the concept of “case series” in the medical literature compared with case reports.

Methods

A PubMed search for articles published during 2009 which had “case series” in their title was performed. A total number of 621 articles were retrieved. 586 papers were included in the analysis and 35 were excluded (18 were commentary letters, 5 were not in English, and twelve could not be retrieved by our Library). The number of patients and category of these articles were analyzed.

Results

The median (range) of the number of cases of articles having “case series” in their title was 7 (1–6432) cases. 186/ 586 articles had less than 5 cases (31.7%, 95% CI (28.3–35.1%)). The median (range) of the number of cases of articles having “case report” as their publication type was 4 (1–178) cases. Out of the 219 articles categorized as case reports 114 (52.1%, 95% CI (45.6–58.6%)) had less than five cases.

Conclusions

The concept of “case series” is not well defined in the literature and does not reflect a specific research design. We suggest that a case series should have more than four patients while four paitents or less should be reported individually as case reports.  相似文献   
68.
目的:用HPLC和电荷转移络合UV法分别测定特非那丁粒剂的含量,并对测定结果进行比较,方法:HPLC法,色谱柱:SpherisorbC8(150*4.6mm,5μm);流动相:甲醇-0.1mol/L三乙胺磷酸缓冲液(80:20),检测波长235nm。电荷转移络合UV法,利用碘与TFN在氯仿中形成电荷转移络合物的原理,在紫外294nm的波长处测定TFN的含量。结果:两法测定的线性范围和平均回收率分别  相似文献   
69.
The study of central nervous system (CNS) leukemia has been hampered by the lack of a suitable animal model. We report that severe combined immunodeficiency (SCID) mice invariably develop rapidly progressive fatal CNS leukemia within 3 weeks after intravenous injection of NALM-6 pre-B acute lymphoblastic leukemia (ALL) cells. Colonization of the dura mater and subarachnoid space, usually of the distal spinal cord with occasional extension into the Virchow-Robin spaces of blood vessels subjacent to the meninges, followed involvement of bone marrow in the skull, vertebrae, and, occasionally, the appendicular skeleton. Occult CNS leukemia was detectable by polymerase chain reaction amplification of human DNA as early as 8 days postinoculation of leukemia cells. We used this in vivo model of human CNS leukemia to examine the therapeutic efficacy and toxicity of intrathecally administered B43 (anti-CD19)-pokeweed antiviral protein (PAP), an anti- B-lineage ALL immunotoxin directed against the pan-B-cell antigen CD19/Bp95. Intrathecal therapy with B43 (anti-CD19)-PAP immunotoxin at nontoxic dose levels significantly improved survival of SCID mice and was superior to intrathecal methotrexate therapy.  相似文献   
70.
Bone regeneration can be accelerated by localized delivery of appropriate growth factors/biomolecules. Localized delivery can be achieved by a 2-level system: (i) incorporation of biomolecules within biodegradable particulate carriers (nanoparticles), and (ii) inclusion of such particulate carriers (nanoparticles) into suitable porous scaffolds. In this study, freeze-dried porous chitosan–gelatin scaffolds (CH–G: 1:2 ratio by weight) were embedded with various amounts of poly(lactide-co-glycolide) (PLGA) nanoparticles, precisely 16.6%, 33.3% and 66.6% (respect to CH–G weight). Scaffolds loaded with PLGA nanoparticles were subjected to physico-mechanical and biological characterizations including morphological analysis, swelling and dissolution tests, mechanical compression tests and cell viability tests. Results showed that incorporation of PLGA nanoparticles into porous crosslinked CH–G scaffolds: (i) changed the micro-architecture of the scaffolds in terms of mean pore diameter and pore size distribution, (ii) reduced the dissolution degree of the scaffolds, and (iii) increased the compressive modulus. On the other hand, the water uptake behavior of CH–G scaffolds containing PLGA nanoparticles significantly decreased. The incorporation of PLGA nanoparticles did not affect the biocompatibility of CH–G scaffolds.  相似文献   
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