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81.
Doppman  JL; Brennan  MF; Dunnick  NR; Kahn  CR; Gorden  P 《Radiology》1981,138(3):557-562
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production.  相似文献   
82.
ObjectiveTo estimate health care systems'' value in treating major illnesses for each US state and identify system characteristics associated with value.Data sourcesAnnual condition‐specific death and incidence estimates for each US state from the Global Burden Disease 2019 Study and annual health care spending per person for each state from the National Health Expenditure Accounts.Study designUsing non‐linear meta‐stochastic frontier analysis, mortality incidence ratios for 136 major treatable illnesses were regressed separately on per capita health care spending and key covariates such as age, obesity, smoking, and educational attainment. State‐ and year‐specific inefficiency estimates were extracted for each health condition and combined to create a single estimate of health care delivery system value for each US state for each year, 1991–2014. The association between changes in health care value and changes in 23 key health care system characteristics and state policies was measured.Data collection/extraction methodsNot applicable.Principal findingsUS state with relatively high spending per person or relatively poor health‐outcomes were shown to have low health care delivery system value. New Jersey, Maryland, Florida, Arizona, and New York attained the highest value scores in 2014 (81 [95% uncertainty interval 72‐88], 80 [72‐87], 80 [71‐86], 77 [69‐84], and 77 [66‐85], respectively), after controlling for health care spending, age, obesity, smoking, physical activity, race, and educational attainment. Greater market concentration of hospitals and of insurers were associated with worse health care value (p‐value ranging from <0.01 to 0.02). Higher hospital geographic density and use were also associated with worse health care value (p‐value ranging from 0.03 to 0.05). Enrollment in Medicare Advantage HMOs was associated with better value, as was more generous Medicaid income eligibility (p‐value 0.04 and 0.01).ConclusionsSubstantial variation in the value of health care exists across states. Key health system characteristics such as market concentration and provider density were associated with value.  相似文献   
83.

Background

In 2002, the World Health Organization published a health system performance ranking for 191 member countries. The ranking was based on five indicators, with fixed weights common to all countries.

Methods

We investigate the feasibility and desirability of using mathematical programming techniques that allow weights to vary across countries to reflect their varying circumstances and objectives.

Results

By global distributional measures, scores and ranks are found to be not very sensitive to changes in weights, although differences can be large for individual countries.

Conclusions

Building the flexibility of variable weights into calculation of the performance index is a useful way to respond to the debates and criticisms appearing since publication of the ranking.  相似文献   
84.
玻璃体切除术治疗外伤性眼内炎62例   总被引:2,自引:1,他引:2  
王金兰  蒋宏苏  惠延年 《医学争鸣》2000,21(2):S018-S018
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…  相似文献   
85.
易军  戴辉  张聚良 《医学争鸣》2000,21(5):86-86
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   
86.
New N-methylpiperazino-substituted quinazolines 8 and 9, phthalazine 13, and quinoline 19 have been synthesized. The receptor binding profiles (α1, 5-HT1A, 5-HT2A) of these compounds and their analogs (7–22) have been determined. It has been demonstrated that orientation of a local dipole moment of the heteroaromatic ring system affects both the α1 and 5-HT2A affinity of the investigated class of ligands. Distortion of the coplanar unfused heteroaromatic ring system results in a decreased 5-HT2A affinity. 4-(4-Methylpiperazino)-2-(2-thienyl)quinoline 18 is the most active and selective α1 ligand (Ki = 4.9 nM) with a much lower affinity for 5-HT1A (Ki = 3420 nM) and 5-HT2A (Ki = 211 nM) receptors.  相似文献   
87.

Objective

To examine hypertension management across countries and over time using consistent and comparable methods.

Methods

A systematic search identified nationally representative health examination surveys from 20 countries containing data from 1980 to 2011 on blood pressure measurements, the diagnosis and treatment of hypertension and its control with antihypertensive drugs. For each country, the prevalence of hypertension (i.e. systolic blood pressure ≥ 140 mmHg or antihypertensive use) and the proportion of hypertensive individuals whose condition was diagnosed, treated or controlled with medications (i.e. systolic pressure < 140 mmHg) were estimated.

Findings

The age-standardized prevalence of hypertension varied between countries: for individuals aged 35 to 49 years, it ranged from around 12% in Bangladesh, Egypt and Thailand to around 30% in Armenia, Lesotho and Ukraine; for those aged 35 to 84 years, it ranged from 20% in Bangladesh to more than 40% in Germany, the Russian Federation and Turkey. The age-standardized percentage of hypertensive individuals whose condition was diagnosed, treated or controlled was highest in the United States of America: for those aged 35 to 49 years, it was 84%, 77% and 56%, respectively. Percentages were especially low in Albania, Armenia, the Islamic Republic of Iran and Turkey. Although recent trends in prevalence differed in England, Japan and the United States, treatment coverage and hypertension control improved over time, particularly in England.

Conclusion

Globally the proportion of hypertensive individuals whose condition is treated or controlled with medication remains low. Greater efforts are needed to improve hypertension control, which would reduce the burden of noncommunicable diseases.  相似文献   
88.
89.

Background  

High-quality, cause-specific mortality data are critical for effective health policy. Yet vague cause of death codes, such as heart failure, are highly prevalent in global mortality data. We propose an empirical method correcting mortality data for the use of heart failure as an underlying cause of death.  相似文献   
90.

BACKGROUND AND PURPOSE

The use of tubulin-binding compounds, which act in part by inhibiting tumour angiogenesis, has become an integral strategy of tumour therapy. Recently, tubulysins were identified as a novel class of natural compounds of myxobacterial origin, which inhibit tubulin polymerization. As these compounds are structurally highly complex, the search for simplified precursors [e.g. pretubulysin (Prt)] and their derivatives is mandatory to overcome supply problems hampering clinical development. We tested the anti-angiogenic efficacy of Prt and seven of its derivatives in comparison to tubulysin A (TubA).

EXPERIMENTAL APPROACH

The compounds were tested in cellular angiogenesis assays (proliferation, cytotoxicity, cell cycle, migration, chemotaxis, tube formation) and in vitro (tubulin polymerization). The efficacy of Prt was also tested in vivo in a murine subcutaneous tumour model induced with HUH7 cells; tumour size and vascularization were measured.

KEY RESULTS

The anti-angiogenic potency of all the compounds tested ran parallel to their inhibition of tubulin polymerization in vitro. Prt showed nearly the same efficacy as TubA (EC50 in low nanomolar range in all cellular assays). Some modifications in the Prt molecule caused only a moderate drop in potency, while others resulted in a dramatic loss of action, providing initial insight into structure–activity relations. In vivo, Prt completely prevented tumour growth and reduced vascular density to 30%.

CONCLUSIONS AND IMPLICATIONS

Prt, a chemically accessible precursor of some tubulysins is a highly attractive anti-angiogenic compound both in vitro and in vivo. Even more simplified derivatives of this compound still retain high anti-angiogenic efficacy.  相似文献   
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