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1.
Although acute ozone (O3) exposure injures tracheal epithelium, the response of the tracheal epithelium to prolonged O3 exposure, and the degree of repair following cessation of exposure have not been previously reported. The purpose of this experiment was to characterize the morphologic response of rat tracheal epithelium to acute (3 days) and prolonged (60 days) exposure to 0.96 ppm O3 as well as to evaluate repair in a 7- and 42-day post-60-day exposure period. Quantitative light- and electron-microscopic evaluation and thymidine labeling indices showed that after 3 days of O3 exposure there was ciliary damage, cell necrosis, an increased density of intermediate cells, and an elevated thymidine labeling index. Following 60 days of exposure, the only major change from controls was the presence of ciliated cells with uniformly short cilia. Tracheal superoxide dismutase levels did not differ between control and 60-day exposure groups. Our findings suggest that the tracheal epithelium adapts to prolonged ozone exposure with the exception of cilia formation in ciliated cells. Complete epithelial recovery occurred by 42 days after exposure.  相似文献   
2.
Surgery has increasingly become a technology-driven specialty. Robotic assistance is considered one innovation within abdominal surgery over the past decade that has the potential to compensate for the drawbacks of conventional laparoscopy. The dramatic evolution of robotic surgery over the past 10 years is likely to be eclipsed by even greater advances over the next decade. We review the current status of robotic technology in surgery. The Medline database was searched for the terms “robotic surgery, telesurgery, and laparoscopy.” A total of 2,496 references were found. All references were considered for information on robotic surgery in advanced laparoscopy. Further references were obtained through cross-referencing the bibliography cited in each work. There is a paucity of control studies on a sufficient number of subjects in robot-assisted surgeries in all fields. Studies that meet more stringent clinical trials criteria show that robot-assisted surgery appears comparable to traditional surgery in terms of feasibility and outcomes but that costs associated with robot-assisted surgery are higher because of longer operating times and expense of equipment. While a limited number of studies on the da Vinci robotic system have proven the benefit of this approach in regard to patient outcomes, including significantly reduced blood loss, lower percentage of postoperative complications, and shorter hospital stays, there are mechanical and institutional risks that must be more fully addressed. Robotic assistance will remain an intensively discussed subject since clinical benefits for most procedures have not yet been proven. While the benefit still remains open to discussion, robotic systems are spreading and are available worldwide in tertiary centers.  相似文献   
3.
We evaluated the optimal preemptive dose of gabapentin for postoperative pain relief after single-level lumbar diskectomy and its effect on fentanyl consumption during the initial 24 hours in a randomized, double-blinded, placebo-controlled study in 100 patients with American Society of Anesthesiologists physical status I and II. Patients were divided into five groups to receive placebo or gabapentin 300, 600, 900, or 1200 mg 2 hours before surgery. After surgery, patients were transferred to the postanesthesia care unit (PACU). A blinded anesthesiologist recorded the pain scores at time points of 6, 12, 18, and 24 hours in the PACU on a Visual Analog Scale (VAS; 0-10 cm) at rest. Patients received patient-controlled analgesia (fentanyl 1.0 mug/kg on each demand with lockout interval of 10 minutes); total fentanyl consumption during initial 24 hours was recorded. Data were entered into the statistical software package SPSS 9.0 for analysis (one-way analysis of variance and Student-Newman-Keuls test). Patients who received gabapentin 300 mg had significantly lower VAS score at all time points. They consumed less fentanyl (patients who received placebo processed 1217.5 +/- 182.0 versus 987.5 +/- 129.6 mug; P < 0.05). Patients who received gabapentin 600, 900, and 1200 mg had lower VAS scores at all time points than patients who received gabapentin 300 mg (P < 0.05). Increasing the dose of gabapentin from 600 to 1200 mg did not decrease the VAS score, nor did the increasing dose of gabapentin significantly decrease fentanyl consumption (702.5, 635, and 626.5 microg). Thus, gabapentin 600 mg is the optimal dose for postoperative pain relief following lumbar diskectomy.  相似文献   
4.
Background: The population in the Gaza Strip has been living under chronically stressful conditions as a result of the ongoing Israeli–Palestinian conflict.

Objectives: To identify health complaints reported by attendants consulting primary care physicians in the Gaza Strip.

Methods: The study took place in 10 governmental primary health care centres and 5 clinics of the United Nations Relief and Works Agency in the Gaza Strip, during autumn 2005. Self-reported health complaints were recorded through face-to-face interviews with 956 respondents using a validated and reliable questionnaire.

Results: Abdominal pain and headache were the most frequent complaints reported among patients aged 18 to 44 years, accounting for 23.3% and 22.7% of total complaints in males and females, respectively. Fatigue and joint pain were the most common complaints among patients aged 45 years and above, accounting for 26% and 33.9% of total complaints in males and females, respectively.

Conclusions: The most common complaints, as reported by patients attending PHC facilities were stress-related and could be attributed to the ongoing conflict and high level of violence and uncertainty in the area. These complaints present a challenge to primary care providers in their efforts to improve the everyday quality of life of Palestinian residents with scarce means and resources.  相似文献   
5.
BACKGROUND: Previous linkage studies have suggested prostate cancer susceptibility genes located on chromosomes 1, 20, and X. Several putative prostate cancer candidate genes have also been identified including RNASEL, MSR1, and ELAC2. Presently, these linkage regions and candidate genes appear to explain only a small proportion of hereditary prostate cancer cases suggesting the need for additional whole genome analyses. METHODS: A genome-wide mode-of-inheritance-free linkage scan, using 405 genetic markers, was conducted on 175 pedigrees, the majority containing three or more affected individuals diagnosed with prostate cancer. Stratified linkage analyses were performed based on previously established criteria. RESULTS: Results based on the entire set of 175 pedigrees showed strong suggestive evidence for linkage on chromosome 17q (LOD = 2.36), with strongest evidence coming from the subset of pedigrees with four or more affected individuals (LOD = 3.27). Race specific analyses revealed strong suggestive evidence for linkage in our African-American pedigrees on chromosome 22q (LOD = 2.35). CONCLUSIONS: Genome-wide analysis of a large set of prostate cancer families indicates new areas of the genome that may harbor prostate cancer susceptibility genes. Specifically, our linkage results suggest that there is a prostate cancer susceptibility gene on chromosome 17 that is independent of ELAC2. Further research including combined analyses of independent genome-wide scan data may clarify the most important regions for future investigation.  相似文献   
6.

Background  

Volume of disease in the sentinel lymph node (SLN) is a significant predictor of additional nodal metastasis. This study assesses incidence of residual non-SLN disease in a large cohort of women with minimal SLN metastases and compares three methods of SLN micrometastasis volume measurement to determine which best predicts residual disease on completion axillary lymph node dissection (cALND).  相似文献   
7.
In the bone marrow (BM) nucleated differential cell count (NDC), myeloblasts are enumerated as a percentage of total nucleated cells, which are inevitably diluted with peripheral blood nucleated cells (PBNC) during BM aspiration. We propose a partial NDC (PNDC) comprising only immature haemopoietic cells capable of division, i.e. myeloblasts, promyelocytes, myelocytes and erythroblasts. We show that the myeloid : erythroid (M : E) ratio of the PNDC remains approximately constant in progressively dilute aliquots of BM aspirates. We determined the PNDC in 22 healthy subjects and investigated the effect of peripheral blood dilution on disease stratification of 66 BM aspirates with myelodysplastic syndromes (MDS). NDC and PNDC myeloblast counts were compared and the equivalent PNDC myeloblast counts for NDC myeloblast threshold counts of 5, 10 and 20% were derived. Reclassification of MDS samples with the PNDC resulted in a change in disease category in 33.3% of 51 MDS samples with NDC myeloblast counts ranging from 3 to 26%. The PNDC is independent of PBNC dilution and can be determined in dilute BM samples. It alters the disease category in a significant proportion of BM aspirates with MDS and has the potential to better stratify MDS to improve clinical outcomes and treatment.  相似文献   
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