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In a retrospective study of 36 patients who developed cardiogenic shock after myocardial infarction, intravenous vasopressin therapy increased mean arterial pressure from 56 to 73 mm Hg at 1 hour (p < 0.001) and maintained it for 24 hours without changing pulmonary capillary wedge pressure, cardiac index, urine output, or other inotropic requirements. After norepinephrine administration, mean pulmonary capillary wedge pressure increased at 1 hour from 21 to 24 mm Hg (p = 0.04); however, this increase was not sustained at 12 and 24 hours. Norepinephrine was associated with a significant increase in cardiac power index at 24 hours, whereas there was only a trend for an increase in cardiac power with vasopressin therapy. In a cohort of patients who developed refractory cardiogenic shock after myocardial infarction, vasopressin was associated with increased mean arterial pressure and no adverse effect on other hemodynamic parameters.  相似文献   
995.
The practice of medicine has extended itself to vast areas and requires active clinicians to systematize and organize their workload through the use of the most up-to-date digital and computer communication technologies. Computerization and worldwide accessibility of information has especially provided great assistance in this regard. The explosive growth of medical information increases the need for the use of these new methods of organizing and accessing data. This article briefly summarizes a few of the vital tools that internet technology has provided clinical practice, with the aid of basic concepts of internet, database systems, hospital systems and data security and reliability.  相似文献   
996.
Abstract: The purpose of this study was to assess the potential value of large-needle core biopsies of normal breast tissue for immunohistochemical studies of epithelial risk assessment. A retrospective analysis was performed to determine the yield of nonatrophic terminal duct lobule units (TDLUs) in 11-gauge vacuum-assisted core biopsies of normal adjacent breast tissue which were included in routine stereotactic core biopsies of benign lesions. Fifty-one patients had a median of two normal tissue cores (range 1–7); 82% of the patients had two or more normal tissue cores; 47% had three or more normal tissue cores. Nonatrophic TDLUs were present in only 47% of patients and in 31% (42 of 137) of all cores. Patients with heterogeneous or dense normal mammographic parenchyma at the site of the biopsy were more likely to have nonatrophic TDLUs, 45% (20 of 44), than patients with fatty normal mammographic parenchyma at the biopsy site, 0% (0 of 7), p = 0.007. Seventy percent (7 of 10) of postmenopausal women on hormone replacement therapy had nonatrophic TDLUs as compared to 41% (11 of 27) of premenopausal and postmenopausal women not on hormones (p = not significant). Eleven-gauge vacuum-assisted core biopsies of normal breast tissue have a low yield of nonatrophic TDLUs suitable for histochemical studies of epithelial risk assessment.  相似文献   
997.
Diagnostic peritoneal lavage (DPL) is an accurate technique to diagnose abdominal visceral injury in blunt abdominal trauma. Four-quadrant abdominal paracentesis should be used routinely in all cases of blunt abdominal injuries as a diagnostic tool. The study included 50 cases in whom four-quadrant abdominal paracentesis was done at JN Medical College, Aligarh. There were 13 positive taps, out of which 12 were true positive and one was false positive. In all 37 negative taps DPL was done, out of which 23 had positive lavage, 22 had true positive and one had false negative results. All the patients with true positive peritoneal lavage had intra-abdominal injuries at laparotomy.  相似文献   
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999.
Three new butenolides (1-3), a new cyclopentenone derivative (4), and a known alcohol (5) were isolated from a marine sponge Homaxinella sp. by bioactivity-guided fractionation. The planar structures were established on the basis of NMR and MS analyses. The stereochemistry of the butenolides and cyclopentenone derivative was defined on the basis of optical rotation and CD spectroscopy. The compounds were tested for cytotoxicity against a panel of five human solid tumor cell lines and displayed marginal to significant activity.  相似文献   
1000.
Loss of heterozygosity (LOH) occurs commonly in cancers causing disruption of tumor suppressor genes and promoting tumor progression. BALB/c-Trp53(+/-) mice are a model of Li-Fraumeni syndrome, exhibiting a high frequency of mammary tumors and other tumor types seen in patients. However, the frequency of mammary tumors and LOH differs among strains of Trp53(+/-) mice, with mammary tumors occurring only on a BALB/c genetic background and showing a high frequency of LOH, whereas Trp53(+/-) mice on a 129/Sv or (C57BL/6 x 129/Sv) mixed background have a very low frequency of mammary tumors and show LOH for Trp53 in only approximately 50% of tumors. We have performed studies on tumors from Trp53(+/-) mice of several genetic backgrounds to examine the mechanism of LOH in BALB/c-Trp53(+/-) mammary tumors. By Southern blotting, 96% (24 of 25) of BALB/c-Trp53(+/-) mammary tumors displayed LOH for Trp53. Karyotype analysis indicated that cells lacking one copy of chromosome 11 were present in all five mammary tumors analyzed but were not always the dominant population. Comparative genomic hybridization analysis of these five tumors indicated either loss or retention of the entire chromosome 11. Thus chromosome loss or deletions within chromosome 11 do not account for the LOH observed by Southern blotting. Simple sequence length polymorphism analysis of (C57BL/6 x BALB/c) F1-Trp53(+/-) mammary tumors showed that LOH occurred over multiple loci and that a combination of maternal and paternal alleles were retained, indicating that mitotic recombination is the most likely mechanism of LOH. Nonmammary tumors of BALB/c mice also showed a high frequency of LOH (22 of 26, 85%) indicating it was not a mammary tumor specific phenomenon but rather a feature of the BALB/c strain. In (C57BL/6 x BALB/c) F1-Trp53(+/-) mice LOH was observed in 93% (13 of 14) of tumors, indicating that the high frequency of LOH was a dominant genetic trait. Thus the high frequency of LOH for Trp53 in BALB/c-Trp53(+/-) mammary tumors occurs via mitotic recombination and is a dominant genetic trait that associates with the occurrence of mammary tumors in (C57BL/6 x BALB/c) F1-Trp53(+/-) mice. These results further implicate double-strand DNA break repair machinery as important contributors to mammary tumorigenesis.  相似文献   
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