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231.
The standard semen analysis frequently fails to identify subfertile males even when findings are normal and conversely often fails to identify fertile males with subnormal semen analyses. This has created the need to produce other tests of sperm physiology that will better distinguish a fertile from a subfertile specimen. Understanding more about the nature of the sperm defect should lead to the establishment of more specific and effective therapies. Until that time, it would still be reasonable to try some of the available empirical therapies even though they may work merely by a placebo mechanism.  相似文献   
232.
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis. Received: 16 February 1998  相似文献   
233.
Gastrointestinal dysfunction among intensive care unit patients   总被引:3,自引:0,他引:3  
This study used the Acute Physiological and Chronic Health Evaluation (APACHE II) system to select two groups of ICU patients with comparable risk of hospital death to evaluate the importance of GI dysfunction, defined as failure to tolerate enteral nutrition (EN), as a prognostic factor. In our ICU, patients who have not undergone recent bowel surgery are treated by EN. Those patients who cannot tolerate EN are treated by total parenteral nutrition (TPN). One hundred and eleven patients who tolerated EN (functioning gut) and 97 TPN patients who failed to tolerate EN (GI dysfunction) were studied. The mean APACHE II scores of the two groups were 17.7 +/- 6.5 (SD) and 17.7 +/- 5.1, respectively. The observed mortality of patients with GI dysfunction (51%) was significantly higher (p less than .0005) than that of patients with a functioning gut (25%). This was associated with significantly poorer APACHE II mean BP, oxygenation, and creatinine scores among the GI dysfunction patients. Our results suggest that shock, ischemia, and hypoxemia, in addition to causing impairment of renal function, may bring about changes in the GI tract, evident clinically only as a failure to tolerate EN, which have an adverse effect on the prognosis of ICU patients so affected.  相似文献   
234.
HIPDM-Single photon emission computed tomography brain imaging was performed during interictal and ictal stages in three patients with complex partial seizures and secondarily generalized tonic-clonic seizures. In all three patients, interictal studies demonstrated decreased regional cerebral perfusion (rCP) and ictal studies showed increased rCP in the epileptogenic region. The demonstration of focal hyperperfusion by SPECT performed during secondarily generalized tonic-clonic seizures suggests that rCP in the epileptic focus remains higher than in other cerebral regions during immediate postictal stages, even in secondarily generalized seizures.  相似文献   
235.
The association of replacement estrogens with breast cancer   总被引:4,自引:0,他引:4  
This epidemiologic case-control study examined the relationship between replacement estrogen use and breast cancer risk in 2 population groups in Hawaii. No significant associations were observed when 161 Caucasian cases were compared with either their neighborhood controls (RR = 0.9; 95% Cl = 0.5-1.3) or their hospital controls (RR = 0.7; 95% Cl = 0.4 to 1.1) and when 183 Japanese cases were compared with either their neighborhood controls (RR = 1.1; 95% Cl = 0.7-1.6) or their hospital controls (RR = 1.0; 95% Cl = 0.6-1.4). The results indicate that the use of replacement estrogens cannot account for the large difference in breast cancer incidence between the 2 Hawaiian ethnic groups. However, further data analysis involving neighborhood controls was suggestive of a possible increase in breast cancer risk with estrogen use for certain sub-groups of women who are at high risk for the disease. These included estrogen users with a family history of breast cancer or a history of benign breast disease. These findings are in agreement with other studies which have used non-hospitalized controls. Because the numbers of cases in this study are not substantial, it is recommended that a large population-based case-control study be undertaken to clarify the relationship between breast cancer risk and replacement estrogen use, especially in sub-groups of women at high risk for the disease.  相似文献   
236.
Background: Remifentanil is commonly used to replace nitrous oxide in general anesthesia to avoid the side effects of the latter. However, there are reports that intraoperative remifentanil infusion can lead to acute opioid tolerance. In this study, the authors tried to determine the dose of remifentanil comparable in efficacy to 70% nitrous oxide and to evaluate its effect on postoperative pain and morphine consumption after colorectal surgery using isoflurane anesthesia.

Methods: Sixty adult patients undergoing open colorectal surgery were randomly assigned to receive either remifentanil or 70% nitrous oxide along with isoflurane anesthesia. After morphine analgesia titration in the postanesthesia care unit, patient-controlled analgesia was commenced. Morphine consumption and pain were scored at rest and during cough or movement for 24 h.

Results: The mean remifentanil infusion rate was 0.17 [mu]g [middle dot] kg-1 [middle dot] min-1. The median visual analog pain score on arrival in the postanesthesia care unit was 1 (0-10) in the nitrous oxide group and 3 (0-9) in the remifentanil group (P < 0.05). Otherwise, there was no difference in pain scores at 5, 10, and 15 min and no difference in the total morphine consumption during the stay in the postanesthesia care unit. The two groups had similar total morphine consumption in the first 24 h and pain scores at rest and during movement. The incidence of postoperative nausea and vomiting was 10% in both groups. There was no difference in the sedation scores.  相似文献   

237.
OBJECTIVE: The aim of this study was to examine the dental condition and oral manifestations in diabetic and nondiabetic uremic patients undergoing hemodialysis. STUDY DESIGN: A total of 128 patients undergoing hemodialysis therapy were classified into the diabetic and nondiabetic groups and examined for uremic oral manifestations, dental caries, and the periodontal status. All the patients received predialytic salivary pH examination. In the diabetic group, the correlation between oral findings and glycemic controlled levels, which was collected based on Hb A1C values, were further studied. RESULTS: The diabetic group exhibited significantly higher prevalence of caries and more severe dry mouth, taste change, and mucosa pain than the nondiabetic group. The diabetic group tended to have lower predialytic salivary pH, and patients with poor glycemic control (ie, Hb A1C > 9%) showed higher incidence of dry mouth, mucosal pain, and tongue coating. However, the DMFT and CPI index were not associated with glycemic control in the diabetic group. CONCLUSIONS: This study reveals that diabetic uremic patients undergoing maintained hemodialysis exhibited a potentially higher risk for dental decay and xerostomia. Lower salivary pH and poor glycemic control may affect oral manifestations. Further research is needed to clarify the combined influence of diabetic nephropathy on oral health.  相似文献   
238.
239.
THIS IS THE FIRST OF 2 ARTICLES EVALUATING cardiac events in patients undergoing noncardiac surgery. In this article, we review the magnitude of the problem, the pathophysiology of these events, approaches to risk assessment and communication of risk. The number of patients undergoing noncardiac surgery worldwide is growing, and annually 500 000 to 900 000 of these patients experience perioperative cardiac death, nonfatal myocardial infarction (MI) or nonfatal cardiac arrest. Although the evidence is limited, a substantial proportion of fatal perioperative MIs may not share the same pathophysiology as nonoperative MIs. A clearer understanding of the pathophysiology is needed to direct future research evaluating prophylactic, acute and long-term interventions. Researchers have developed tools to facilitate the estimation of perioperative cardiac risk. Studies suggest that the Lee index is the most accurate generic perioperative cardiac risk index. The limitations of the studies evaluating the ability of noninvasive cardiac tests to predict perioperative cardiac risk reveals considerable uncertainty as to the role of these popular tests. Similarly, there is uncertainty as to the predictive accuracy of the American College of Cardiology / American Heart Association algorithm for cardiac risk assessment. Patients are likely to benefit from improved estimation and communication of cardiac risk because the majority of noncardiac surgeries are elective and accurate risk estimation is important to allow informed patient and physician decision-making.  相似文献   
240.
SUMMARY: Large simulations have become increasingly complex in many fields, tending to incorporate scale-dependent modeling and algorithms and wide-ranging physical influences. This scale of simulation sophistication has not yet been matched in neuroscience. The authors describe a framework aimed at enabling natural interaction with complex simulations: their configuration, initial conditions, monitoring, and analysis. The architecture is built on three cornerstone components: active probes, adaptive data capture, and visual interface. The resulting synthesis will enable interactive exploration of live simulations running on supercomputing platforms.  相似文献   
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