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101.
Comparing clinical productivity is important for strategic planning and the evaluation of resource allocation in any large organization. This process of benchmarking performance allows for the comparison of groups with similar characteristics. However, this process is often difficult when comparing the operative service productivity of large and small military treatment facilities because of the significant heterogeneity in mission focus and case complexity. However, in this article, we describe the application of a new method of benchmarking operative service productivity based on normalizing data for operating room sites, cases, and total American Society of Anesthesiologists units produced per hour. We demonstrate how these benchmarks allow for valid comparisons of operative service productivity among these military treatment facilities and how the data could be used in expanding or contracting operating locations. In addition, these benchmarks are compared with those derived from the use of this system in the civilian sector.  相似文献   
102.
The aim of this study is to understand the value of specific sites in extended peripheral and transition zone biopsy schemes in order to define the optimal systematic biopsy regimen correlated with the percentage of positivity of each single bioptic site. A total of 165 consecutive patients underwent transrectal ultrasonography examination to detect prostate cancer followed by a lesion-directed and systematic 14-step biopsy scheme. The detection rate was examined for the lesion-directed and for each zone region biopsy. The frequency of positive biopsies in the various prostate regions was determined to evaluate the diagnostic yield of each biopsy site. Analysis was stratified for prostate-specific antigen (PSA), free-to-total PSA ratio, age, prostate size and digital rectal examination. The biopsy protocol detected 40% of patients (66/165) as positive and 55.1% (91/165) as negative for cancer. Standard sextant biopsy was expected to detect only 51 cancer on 66, lateral peripheral (PZ), transition (TZ) and central zone (CZ) biopsies only 56 cancer on 66, while the combination of sextant, PZ, TZ and CZ biopsies, for a total of 14 zone biopsies, detected 64 on 66 patients with cancer (97%) at recruitment. Sampling only the eight prostate regions with higher frequency of positive cancer biopsy was expected to detect 61 cancer patients against the 64 found with the 14-step scheme. This eight-biopsy regimen outperforms the conventional sextant regimen in cancer detection rate (93 vs 77%) and has an overall detection rate lower by only 3.1% (36.9 vs 40%) compared to the 14-biopsy regimen. This difference in detection rate is even smaller in patients with PSA values <10 ng/ml, age <70 y and prostate size <50 ml. This eight-biopsy scheme, including sampling in PZ and TZ toward the base, should be considered in an initial biopsy scheme to maintain a similar detection rate of an extensive biopsy scheme reducing the number of biopsies.  相似文献   
103.
BACKGROUND: Terazosin and tamsulosin are drugs currently used in the treatment of benign prostatic hypertrophy (BPH). The potency of these two alpha(1) receptor antagonists and that of prazosin to inhibit contractions induced by noradrenaline and the binding of [(3)H]-prazosin in human prostate and four different human arterial and venous vessels (saphenous and umbilical veins, renal and mesenteric arteries) was studied. METHODS: By bioassay and binding studies, we examined the receptor affinities of different alpha(1) receptor antagonists in different human tissues. RESULTS: pKb of terazosin, tamsulosin, and prazosin obtained in the prostatic tissues (8.15, 9.64, and 8.59, respectively) were not different from those obtained in the umbilical veins (8.07, 9.56, and 8.30, respectively), in the mesenteric artery (8.27, 10.29, and 9.01, respectively), renal artery (8.35, 10.13, and 8.76, respectively) and saphenous vein (7.8, 10.3, and 9.32, respectively). IC(50) (nM) of prazosin, terazosin, and tamsulosin obtained from binding studies in membrane preparations from prostate tissue were similar to those from umbilical veins, saphenous vein, and renal artery. CONCLUSIONS: All of the evaluated drugs showed similar selectivity for prostatic vs. vascular tissues. Thus, different clinical profiles of the present drugs should not result from their differential affinity for prostatic versus vascular alpha(1)-adrenoceptors.  相似文献   
104.
The response to vascular injury is a complex wound healing response involving cell proliferation, migration, remodeling and inflammation. In the present studies we employed a rat balloon angioplasty model of vascular injury to investigate the potential role of sphingolipid signaling in the response to vascular injury. The enzyme serine palmitoyltransferase (SPT) catalyzes the first committed step in de novo sphingolipid biosynthesis. We observed marked upregulation of expression of both SPT subunits in actively proliferating cells in injured vessels. This enhanced SPT expression occurs in de-differentiated fibroblasts and proliferating vascular smooth muscle cells. The upregulation is particularly apparent in the proliferating luminal edge of the neointima and the adventitial de-differentiated fibroblasts and may serve as a hallmark of this process. The possible functional consequences of this enzyme upregulation and its role in the response to vascular injury are suggested but remain to be determined.  相似文献   
105.
106.
Expression of protease-activated receptor-1 (PAR-1), a cell-surface receptor for thrombin, is increased in balloon-injured rat carotid artery and human atherosclerotic tissue. To examine the role of PAR-1 in vascular injury, we compared vascular injury responses in wild-type (WT) and PAR-1-deficient (PAR-1(-/-)) mice. Arterial injury was induced by inserting a flexible guidewire into the common carotid artery and withdrawing it 6 times with rotation. Bromodeoxyuridine, delivered subcutaneously by osmotic minipump, was used to measure cellular proliferation. Mice were perfusion-fixed at 1, 2, 5, 10, and 14 days after injury. Extensive endothelial damage, mural thrombosis, platelet adherence, and medial smooth muscle cell loss and necrosis were apparent at day 1 in both WT and PAR-1(-/-) mice. The incidence of thrombosis or platelet deposition in WT and PAR-1(-/-) mice declined from 100% at day 1 to 25% and 21%, respectively, at 14 days. Endothelial disruption, as assessed by Evan's blue uptake, was maximum at day 1 and declined by day 14. This apparent endothelial regrowth was similar in WT and PAR-1(-/-) mice. Significant medial thickening at 14 days after injury was similar in WT (from 22.8+/-1.7 to 30.7+/-1.9 microm) and PAR-1(-/-) (from 23.2+/-2.1 to 30.5+/-2.2 microm) mice. Medial area also increased in response to injury but to a lesser extent in PAR-1(-/-) mice (from 0.0250+/-0.0044 to 0.0312+/-0.0047 mm(2)) than in WT mice (from 0.0266+/-0.0040 to 0.0398+/-0.0050 mm(2)). Neointima was variable and occurred in 6 of 13 WT and 5 of 12 PAR-1(-/-) mice. However, intimal area tended to be less in PAR-1(-/-) mice (0. 0016+/-0.0007 mm(2)) compared with WT mice (0.0082+/-0.0032 mm(2)), although this difference did not achieve statistical significance (P=0.06). Cell density was significantly greater in normal carotids from PAR-1(-/-) (6.4+/-0.5 x 10(3)/mm(2)) compared with WT (4.3+/-0. 8 x 10(3)/mm(2)) mice and remained elevated after injury. Vessel and lumen diameters tended to increase in WT mice after injury, whereas vessel diameter was unchanged and lumen diameter actually decreased in PAR-1(-/-) mice. Cell proliferation in injured carotid arteries was similar in PAR-1(-/-) and WT mice. These data suggest that PAR-1(-/-) may play a role in vascular injury responses in this mouse model via possible effects on extracellular matrix regulation.  相似文献   
107.
Epidermal growth factor (EGF)-related proteins such as transforming growth factor alpha (TGF-alpha) control cancer cell growth through autocrine and paracrine pathways. Overexpression of TGF-alpha and/or its receptor (EGFR) has been associated with a more aggressive disease and a poor prognosis. The blockade of EGFR activation has been proposed as a target for anticancer therapy. Monoclonal antibody (MAb) C225 is an anti-EGFR humanized chimeric mouse MAb that is presently in Phase II clinical trials in cancer patients. Previous studies have suggested the potentiation of the antitumor activity of certain cytotoxic drugs, such as cisplatin and doxorubicin, in human cancer cell lines by treatment with anti-EGFR antibodies. We have evaluated in human ovarian, breast, and colon cancer cell lines, which express functional EGFR, the antiproliferative activity of MAb C225 in combination with topotecan, a cytotoxic drug that specifically inhibits topoisomerase I and that has shown antitumor activity in these malignancies. A dose-dependent supraadditive increase of growth inhibition in vitro was observed when cancer cells were treated with topotecan and MAb C225 in a sequential schedule. In this respect, the cooperativity quotient, defined as the ratio between the actual growth inhibition obtained by treatment with topotecan followed by MAb C225 and the sum of the growth inhibition achieved by each agent, ranged from 1.2 to 3, depending on drug concentration and cancer cell line. Treatment with MAb C225 also markedly enhanced apoptotic cell death induced by topotecan. For example, in GEO colon cancer cells, 5 nM topotecan, followed by 0.5 microg/ml MAb C225, induced apoptosis in 45% cells as compared with untreated cells (6%) or to 5 nM topotecan-treated cells (22%). Treatment of mice bearing established human GEO colon cancer xenografts with topotecan or with MAb C225 determined a transient inhibition of tumor growth because GEO tumors resumed the growth rate of untreated tumors at the end of the treatment period. In contrast, an almost complete tumor regression was observed in all mice treated with the two agents in combination. This determined a prolonged life span of the mice that was significantly different as compared with controls (P < 0.001), to MAb C225-treated group (P < 0.001), or to the topotecan-treated group (P < 0.001). All mice of the topotecan plus MAb C225 group were the only animals alive 14 weeks after tumor cell injection. Furthermore, 20% of mice in this group were still alive after 19 weeks. The combined treatment with MAb C225 and topotecan was well tolerated by mice with no signs of acute or delayed toxicity. These results provide a rationale for the evaluation of the anticancer activity of the combination of topoisomerase I inhibitors and anti-EGFR blocking MAbs in clinical trials.  相似文献   
108.
BACKGROUND: Joint angular velocity (the rate of flexion and extension of a joint) is related to the dynamics of muscle activation and force generation during walking. Therefore, the goal of this research was to examine the joint angular velocity in normal and spastic gait and changes resulting from muscle-tendon lengthening (recession and tenotomy) in patients who have spastic cerebral palsy. METHODS: The gait patterns of forty patients who had been diagnosed with spastic cerebral palsy (mean age, 8.3 years; range, 3.7 to 14.8 years) and of seventy-three age-matched, normally developing subjects were evaluated with three-dimensional motion analysis and electromyography. The patients who had cerebral palsy were evaluated before muscle-tendon lengthening and nine months after treatment. RESULTS: The gait patterns of the patients who had cerebral palsy were characterized by increased flexion of the knee in the stance phase, premature plantar flexion of the ankle, and reduced joint angular velocities compared with the patterns of the normally developing subjects. Even though muscle-tendon lengthening altered sagittal joint angles in gait, the joint angular velocities were generally unchanged at the hip and knee. Only the ankle demonstrated modified angular velocities, including reduced dorsiflexion velocity at foot-strike and improved dorsiflexion velocity through mid-stance, after treatment. Electromyographic changes included reduced amplitude of the gastrocnemius-soleus during the loading phase and decreased knee coactivity (the ratio of quadriceps and hamstring activation) at toe-off. Principal component analyses showed that, compared with joint-angle data, joint angular velocity was better able to discriminate between the gait patterns of the normal and cerebral palsy groups. CONCLUSIONS: This study showed that muscle-tendon lengthening corrects biomechanical alignment as reflected by changes in sagittal joint angles. However, joint angular velocity and electromyographic data suggest that the underlying neural input remains largely unchanged at the hip and knee. Conversely, electromyographic changes and changes in velocity in the ankle indicate that the activation pattern of the gastrocnemius-soleus complex in response to stretch was altered by recession of the complex.  相似文献   
109.
The current study aims to compare injectable and oral first-line disease-modifying therapies (DMTs) for time to first relapse, time to confirmed disability progression (CDP), and time to discontinuation using a cohort of relapsing remitting multiple sclerosis (RRMS) patients, with data extracted from the Italian MS Register. This multicenter, observational, retrospectively acquired, and propensity-adjusted cohort study utilized RRMS-naïve patients from the Italian MS Register who started either injectable or oral first-line DMTs between January 1, 2010, and December 31, 2017, to evaluate the impact on disability outcomes in patients. Enrolled patients were divided into two groups, namely the injectable group (IG) and the oral group (OG). Of a cohort of 11,416 patients, 4602 were enrolled (3919 in the IG and 683 in the OG). The IG had a higher rate of women (67.3% vs 63.4%, p < 0.05) and a lower mean age (36.1 ± 10.9 vs 38.9 ± 11.8, p < 0.001). The event time to first relapse demonstrated a lower risk in the OG (HR = 0.58; CI 95% 0.48–0.72, p < 0.001). However, no differences were found between the two groups with respect to the risk of CDP (HR = 0.94; CI 95% 0.76–1.29, p = 0.941), while a lower risk of DMT was found in the OG (HR = 0.72; CI 95% 0.58–0.88, p = 0.002) for the event time to discontinuation. Real-world data from the Italian MS Register suggests that first-line oral DMTs are associated with a lower risk of experiencing a new relapse and of therapy discontinuation compared to injectable DMTs.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-020-01001-6.Key Words: Multiple sclerosis, injectable DMTs, oral DMTs, real-world setting, EDSS score  相似文献   
110.
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