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11.
The anatomical relationship between the kidney position and its arterial supply was investigated in 21 mammals, 1 bird, and 3 reptiles (n = 1 for each species) and in 43 human cadavers. The following observations were made. (1) Although the right kidney was located caudal to the left kidney in 29 out of 43 human cadavers (67.4%), the origin of the right renal artery from the aorta was located cranial to the origin of the left renal artery in 36 human cadavers (83.7%). Therefore, the relative positions of the kidneys do not correspond with the relative origins of the renal arteries in humans. (2) Among the mammals that were examined, the position of the kidney and the branching level of the renal artery on the right side were usually cranial to those on the left side. (3) In the bird and most reptiles that were examined, kidneys were typically located in the pelvic region and were supplied by segmental arterial branches. These results suggest that the right kidney and its arterial supply are generally located cranial to the left kidney in phylogeny of mammals. While the presence of a human accessory renal artery in 9 out of 86 sides (10.5%) and a cranial origin of the left renal artery relative to the right renal artery in 7 out of 43 cadavers (16.3%), shows some variation in the arterial supply to the kidneys, the origin of the renal arteries can generally be used as phylogenetic landmarks indicating the relative positions of the kidneys. Hence, from an ontological perspective, the human right kidney may be initially situated cranial to the left kidney during the early stages of development. Thereafter, the human right kidney may shift downwards secondary.  相似文献   
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Background/Purpose

The aim of this study was to investigate the current use of antibiotic prophylaxis (AP) in association with pancreatoduodenectomy (PD) in Japan, and to determine its surgical implications.

Methods

We surveyed 2331 patients who underwent PD for treatment of disease in the periampullary region. Data, obtained during the period January 2002 through December 2003, from 111 major surgical services associated with the Japanese Society for Pancreatic Surgery, were analyzed with regard to patient characteristics, preoperative complications, AP, and postoperative morbidities.

Results

Eighty-five (78.7%) of the 108 eligible institutions chose a first- or second-generation cephalosporin for AP, given for a mean duration of 4.3 days. At all but 1 institution, the first dose was administered prior to surgical incision of the skin. At 42% of the institutions, an additional antibiotic was administered during surgery. The overall rate of wound infection was 6.8% of the 2266 patients for whom data were available. Preoperative jaundice was found in 55.3% of these 2266 patients, and 92.6% of these jaundiced patients were suffering from preoperative infections. In addition, those with preoperative infections were also diagnosed as having biliary infections. The number of patients with preoperative jaundice in combination with preoperative infections was significantly related to the rate of postoperative morbidity (P < 0.0001).

Conclusions

Administration of AP in association with PD in Japan seems appropriate. Icteric patients with biliary infections are at high risk for postoperative morbidities and need careful monitoring after surgery.  相似文献   
19.
Cleavage of the hemagglutinin (HA) in tissue culture systems has been correlated with virulence of avian influenza viruses. To examine the structural requirements for cleavage of the HA, the HA gene from a virulent H5 influenza virus was expressed in mammalian cells (CV-1), and the cleavage site of the HA was explored by using site-specific mutagenesis. The expressed HA protein exhibited normal cleavage, transport to the cell membrane, and ability to adsorb and to fuse erythrocytes at pH 5. Site-specific mutagenesis of the HA directly established that (i) most of the basic amino acids at this site are critical for cleavage activation; (ii) besides the connecting peptide sequence, at least one other structural feature of the HA is required for enzyme recognition; and (iii) the length of the connecting peptide can abrogate the structural feature(s).  相似文献   
20.
This study was conducted to clarify the characteristics of colestimide responders. Forty-seven non-diabetic patients with high levels of low-density lipoprotein cholesterol (LDL-C) received colestimide at 3,000 mg/day and were followed up for 4 months. After 4 months, body weight was reduced but the change was not statistically significant. Total serum cholesterol (TC) and LDL-C levels significantly decreased from 280 to 232 mg/dl and from 195 to 150 mg/dl, respectively (p<0.01 versus before colestimide was administered). Serum triglyceride (TG) levels increased, but the change was not significant. Preheparin lipoprotein lipase mass (preheparin LPL mass) at baseline was significantly higher in colestimide responders (greater than a 20% decrease of LDL-C: n=28) than non-responders (76.2 ng/ml versus 50.3 ng/ml, p<0.05: n=19). Next, the subjects were divided into those with a high (n=33) and low (n=14) preheparin LPL mass at baseline. LDL-C levels were significantly decreased in patients with a high preheparin LPL mass while TG levels were significantly increased in patients with a low preheparin LPL mass. These results suggest that baseline preheparin LPL mass may be a marker of the response to colestimide.  相似文献   
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