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排序方式: 共有890条查询结果,搜索用时 46 毫秒
1.
Yair Lotan Matthew T Gettman Claus G Roehrborn Margaret S Pearle Jeffrey A Cadeddu 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2003,7(2):111-115
BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated. 相似文献
2.
Selective elimination of mRNAs in vivo: complementary oligodeoxynucleotides promote RNA degradation by an RNase H-like activity. 总被引:29,自引:11,他引:18
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P Dash I Lotan M Knapp E R Kandel P Goelet 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(22):7896-7900
Oligodeoxynucleotides lead to translation arrest of complementary mRNAs in the wheat germ translation system by a degradation of the mRNA. In an attempt to develop an effective reverse genetic approach in vivo, we demonstrate that injection of short (15- to 30-nucleotide) oligonucleotides into Xenopus oocytes leads to complete degradation of both injected and endogenous mRNAs by means of an RNase H-like activity. 相似文献
3.
Nathan Dascal Ilana Lotan Yoram Lass 《Pflügers Archiv : European journal of physiology》1987,409(4-5):521-527
InXenopus follicular oocytes, activation of muscarinic receptors evokes a slow potassium current (H-response); a similar current is evoked by intracellular injection of cyclic guanosine 3,5-monophosphate, cGMP (Dascal et al. 1984). We have tested the hypothesis that cGMP may be the second messenger that mediates the opening of K channel by acetylcholine (ACh). ACh elevated the intracellular level of cGMP with a time course similar to that of the development of the muscarinic H-response; maximal increase in cGMP concentration above the control was about 0.2 pmole/oocyte. The amount of injected cGMP that produced a detectable K current (threshold dose) varied between 0.5 and 3 pmole/oocyte. At low doses of cGMP, the slope of log dose-log response curve was about 2.5, suggesting involvement of a biochemical process with a positive cooperativity of at least 3. Higher doses of cGMP evoked, in addition to the outward current, an irregular, rapidly developing, long-lasting inward current, that never reached amplitudes comparable to those of ACh-evoked Cl currents. The K current elicited by cGMP was insensitive to elevation or depletion of external Ca. It was potentiated by isobutylmethylxanthine (IBMX). ACh strongly inhibited the cGMP-evoked K current when applied at the plateau of the latter. 4-Phorbol 12,13-dibutyrate (PDBu) (1 M) rapidly and completely inhibited the cGMP response. It is concluded, that most of the results presented in this report contradict the hyothesis that cGMP is the intracellular mediator of ACh-induced changes in membrane conductance in the oocytes.Abbreviations ACh
acetylcholine
- cAMP
cyclic adenosine 3,5-monophosphate
- cGMP
cyclic guanosine 3,5-monophosphate
- EGTA
ethylenediaminetetraacetic acid
- Hepes
N-2-hydroxyethyl-piperazinc-N-2-hydroxypropanesulphonic acid
- IBMX
3-isobutyl-l-methylxanthine
- IP3
inositol 1,4,5-trisphosphate
- PDBu
4-phorbol 12,13-dibutyrate 相似文献
4.
A family with hypobetalipoproteinaemia with 10 affected members is described. In six patients low density lipoprotein cholesterol (LDL-c) concentrations were about 10 % of normal. In four LDL-c was reduced to about 50 % of normal; these four patients probably represent the "intermediate" form of hypobetalipoproteinaemia. This variation in total cholesterol concentration and LDL-c among the affected individuals of the same family could reflect differences of expression in a single aberrant gene or additive expression of a gene at a second locus. 相似文献
5.
Mina Ben-bassat Diana Braslavsky Danny Lotan Bella Eisenstein Miriam Davidovitz Harry Stark 《Ultrastructural pathology》1988,12(1):1-16
In an attempt to recognize early stages of focal segmental glomerulosclerosis (FSGS) in patients with a clinical course suggesting a diagnosis other than minimal change disease (MCD) and normal histology, or minor, nondiagnostic changes on light microscopy (LM), we used a protocol for systematic and extensive electron microscopy (EM) examination of kidney biopsies obtained from such patients. By this method ultrastructural pathology was found in 8 patients. These changes were localized, involving only portions of single glomerular segments. The findings included mild to moderate increase of the mesangial matrix, focal wrinkling of the capillary basement membrane, and early obliteration of the normal architecture of individual capillary loops, as well as electron-dense deposits in a mesangial and subendothelial distribution. Of these 8 patients, 2 are at present in remission without therapy (in 1, following therapy with cyclophosphamide); 3 are in remission on steroid therapy; 1 developed massive proteinuria during pregnancy, after a spontaneous remission lasting almost 2 years; 1 patient advanced to terminal renal failure 3 1/2 years after biopsy; and 1 died of sepsis 1 month after biopsy. We believe that the ultrastructural changes found may represent early or mild FSGS and that the protocol described can add valuable information in clinically worrisome patients in whom renal histology appears normal. 相似文献
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8.
The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) has been shown to induce apoptosis in various malignant cells including human prostate carcinoma cells (HPC). We examined several possible mechanisms by which 4HPR could induce apoptosis in HPC cells. 4HPR exhibited concentration- and time-dependent decrease in cell number both in androgen-dependent (LNCaP) and -independent (DU145 and PC-3) cells. The 4HPR concentrations causing 50% decrease in cell number in LNCaP, DU145, and PC-3 cultures were 0.9 +/- 0.16, 4.4 +/- 0.45, and 3.0 +/- 1.0 microM, respectively, indicating that LNCaP cells were more sensitive to 4HPR than the other cells. 4HPR-induced apoptosis in all three cell lines was evidenced by increased enzymatic labeling of DNA breaks and formation of a DNA ladder. 4HPR increased the level of reactive oxygen species, especially in LNCaP cells. 4HPR-induced apoptosis could be suppressed in LNCaP cells by antioxidant and in DU145 cells by a nuclear retinoic acid receptor-specific antagonist, suggesting the involvement of reactive oxygen species or retinoic acid receptors in mediating apoptosis induced by 4HPR in the different HPC cells. Furthermore, 4HPR modulated the expression levels of some apoptosis-related gene (p21, c-myc, and c-jun), which may also contribute to the induction of apoptosis by 4HPR in HPC cells. 相似文献
9.
Histone deacetylase inhibitors such as sodium butyrate or (R)-trichostatin A {(R)-TSA; 7- [4-(dimethylamino) phenyl]-N-hydroxy-4,6-dimethyl-7-oxo-2, 4-heptadienamide} have been reported to modulate the proliferation and differentiation of certain cell types. In this study, we analyzed the effects of these agents on KM12 human colon carcinoma (HCC) cells in culture. We found that (R)-TSA induced cell flattening, inhibited anchorage-dependent and anchorage-independent growth, increased the level of the differentiation marker carcinoembryonic antigen, and increased the expression of gelsolin, a candidate tumor suppressor, in these HCC cells. Cells treated with (R)-TSA for 3 h exhibited a high degree of histone (primarily H4) acetylation. (R)-TSA exerted these effects at concentrations in the range between 0.1 to 1 mu M that are at least 1,000 times lower than those required to achieve similar effects by n-butyrate. Trichostatin C, which exhibits some histone deacetylase inhibitory activity but not the analogs (S)-TSA or (R)- or (S)-trichostatic acid, which lack histone deacetylase inhibitory activity, also showed some growth inhibitory activity. These results indicate that histone deacetylase inhibitors may lead to suppression of the transformed phenotype and enhanced differentiation in the KM12 HCC cells. 相似文献
10.
Implications of the prostate cancer prevention trial: a decision analysis model of survival outcomes. 总被引:2,自引:0,他引:2
Yair Lotan Jeffrey A Cadeddu J Jack Lee Claus G Roehrborn Scott M Lippman 《Journal of clinical oncology》2005,23(9):1911-1920
PURPOSE: To assess the estimated effect of finasteride prevention of prostate cancer on overall survival. METHODS: Data for our decision tree model came from men in the two arms (finasteride or placebo) of the Prostate Cancer Prevention Trial (PCPT) and from clinically localized prostate cancer patients studied for long-term survival outcomes. Our model compared survival outcomes for men treated with finasteride or placebo. Prostate cancer rates were based on the 7-year period prevalence of prostate cancer detected in the PCPT; survival probabilities were abstracted from the long-term outcome studies. We assessed variability in the PCPT and long-term survival studies to test the variability of our model. RESULTS: Survival advantages for a finasteride-treated (v those not treated with finasteride) population include gains of 1.7 months in 15-year cause-specific survival (assuming finasteride-altered Gleason scores and prostate cancer prevalence rates in the PCPT), of up to 3 months for cancers treated conservatively or surgically (assuming finasteride does not alter Gleason scores), and of 0.35 months (assuming the rate of cancers detected by for-cause biopsies in the PCPT), which increased to 1.7 months when assuming a 30% rate of biopsy-detected cancer in the PCPT placebo group. Model-variability analyses support several survival benefits associated with finasteride (eg, the uniform benefits assuming finasteride does not alter Gleason scores) but question certain others (eg, in 15-year recurrence-free survivals assuming finasteride does alter Gleason scores). CONCLUSION: Finasteride can impart survival benefits according to our model, especially when we assume that finasteride does not alter Gleason scores. 相似文献