Role of CT angiography in the preoperative evaluation for laparoscopic nephrectomy

Laparoscopic nephrectomy (LN) was recently introduced as a minimally invasive alternative to open nephrectomy in living related renal donation. Because of the limited field of view available with laparoscopic techniques, the role of preoperative radiologic evaluation in LN has expanded to include anatomic definition of the renal arteries, collecting system, renal parenchyma, and renal venous anatomy. Computed tomographic (CT) angiography has proved to be a minimally invasive alternative to conventional angiography in the preoperative evaluation of living related renal donors. CT angiography has been shown to have an accuracy comparable to that of conventional angiography in predicting renal arterial anatomy. In addition, CT angiography provides comprehensive definition of the renal vascular anatomy including the location, size, and length of the renal, adrenal, gonadal, and lumbar veins. Dual-phase spiral CT combined with three-dimensional CT angiography constitute a single, minimally invasive procedure that can provide a complete preoperative evaluation of potential living related renal donors prior to LN. Comprehensive anatomic depiction of the renal arterial and venous supplies aids in surgical planning and helps avoid potential complications.     

Short-term memory impairment and arithmetical ability

We document the dissociation of preserved calculation skills in a patient with impaired auditory short-term memory. The patient (MRF) had a memory span of three digits. Furthermore, he showed rapid decrement in performance of single digits and letters with both auditory and visual presentation in the Brown-Peterson forgetting task. Analysis of his calculation skills revealed a normal ability to solve auditorily presented multidigit addition and subtraction problems such as 173 + 68 and to execute the Paced Auditory Serial Addition Task (Sampson, 1956, 1958; Gronwall, 1977). In addition, his performance on other tests, including arithmetic manipulation of natural numbers, decimals and fractions, approximation, magnitude, ratio, and percentage, appeared to be normal (Hitch, 1978b). It is argued that these findings require a revision of Baddeley and Hitch's (1974) concept of the function of working memory.     

一种摩托车用ABS的试验研究

本文详细介绍了一种摩托车用ABS的结构，设计了其输入输出特性的试验方案，并测定了输入输出特性。根据结构和输入输出特性分析了该装置的工作原理，认为该ABS实际上只是一个限压装置，以用来防止抱死，有很大的局限性。     

Controlled-release products for the control of the estrus cycle in cattle, sheep, goats, deer, pigs, and horses

This paper describes the estrus cycles of a number of livestock breeds and reviews the controlled-release drug delivery systems that are currently available for the purpose of controlled breeding. The bovine estrus cycle is reviewed in detail, and the estrus cycles of other species are described in a manner that highlights similarities and differences between species. Pertinent formulation and pharmacokinetic information about current drug delivery systems is presented and discussed, and recent advances in this area are also described.     

A novel interpretation of Prony's method

The two key steps in Prony's method are interpreted as two key approximation problems. In the first, a nonhomogeneous, constant coefficient, linear difference equation is fitted to the samples. This difference equation is fitted so that the nonhomogeneous part of the difference equation is minimized in the least-squares sense. For the second problem, a homogeneous solution to the difference equation is obtained that minimizes the particular solution. This homogeneous solution is used to approximate the general solution     

Cell cycle regulation of human pancreatic cancer by tamoxifen

BACKGROUND: Clinical trials have suggested a survival advantage for selected patients with metastatic pancreatic cancer treated with tamoxifen. We sought to identify the molecular mechanism by which tamoxifen inhibits human pancreatic cancer cell (HPCC) growth. METHODS: HPCCs were grown in tamoxifen and growth inhibition was determined by 3H-thymidine uptake and by the MTT assay; changes in cell viability were determined by cell counts. Cell cycle alterations were evaluated by FACS, and the induction of apoptosis was evaluated using the TUNEL assay. Total cellular RNA was isolated after tamoxifen treatment, and Northern blot analysis was performed for p21waf1. RESULTS: Tamoxifen inhibited HPCC growth as measured by inhibition of 3H-thymidine incorporation and by the MTT assay. However, there was no decrease in the total number of viable cells after 6 days of treatment with 10 microM of tamoxifen and no evident apoptosis, confirming the absence of a cytotoxic effect. Cell cycle analysis revealed cellular arrest in the G0/G1 phase, which correlated with p21waf1 mRNA upregulation in response to tamoxifen treatment. CONCLUSIONS: Tamoxifen inhibits HPCC growth by inducing G0/G1 arrest with an associated increase in p21waf1 mRNA expression. Tamoxifen is an effective inhibitor of HPCC growth in vitro and warrants further in vivo study.