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991.
992.
Complete prolapse of rectum (procedentia) is said to occur when the full circumference of the rectal wall is everted through the anus. Numerous techniques have been developed in order to treat procedentia, an uncommon pathology that is managed occasionally by the general surgeon. A simple, safe and effective procedure is recommended for surgeons who treat procedentia recti once in a while. We describe a simple rectopexy procedure which has been used effectively in 38 patients in the last 10 years. In this prospective study we evaluated the results which are comparable to other standard operative techniques in terms of morbidity, anatomic correction and bowel function. This technique is based on sound scientific principles in the aetiopathogenesis of rectal prolapse. This procedure obliterates the abnormally deep cul de sac of rectovesical pouch and supports the anterior rectal wall by suturing it to the bladder base to prevent initiation of sliding herniation of anterior rectal wall, which causes procedentia recti. Posterior dissection fibrosis fixes the posterior rectal wall to the sacrum after healing and restores the normal posterior curve of rectal canal and corrects the pathogenic straightening of rectum which promotes prolapse. Minimal mobilization of rectum is done and lateral ligaments are not dissected hence all attendant complications e.g. impotence, urinary incontinence, constipation etc are avoided. Simplicity, effectiveness, safety and non requirement of prosthetic material makes it an ideal operation suitable for a general surgeon working in the periphery.KEY WORDS: Procedentia, Rectopexy  相似文献   
993.
Aims: To investigate the correlation between the ‘perfusion index’ (PI) and other commonly used estimates of cutaneous blood flow [heart rate (HR), surface temperatures (ST) and central‐to‐peripheral thermal gradients (C‐P grad)] and to use this new non‐invasive tool to compare differences between prone and supine sleep position in low birth weight (LBW) infants. Methods: Six‐hour continuous recordings of pulse oximetry, cardiac activity and absolute ST from three sites (flank, forearm and leg), along with minute‐to‐minute assessment of behavioural states were performed in 31 LBW infants. Infants were randomly assigned to the prone or supine position for the first 3 h and then reversed for the second 3 h. PI data were correlated with HR and C‐P grad, and compared across sleep positions during quiet sleep (QS) and active sleep (AS). Results: Perfusion index correlated significantly with HR (r2 = 0.40) and flank‐to‐forearm thermal gradient (r2 = 0.28). In the prone position during QS, infants exhibited higher PI (3.7 ± 0.9 vs. 3.1 ± 0.7), HR (158.4 ± 8.9 vs. 154.1 ± 8.8 bpm), SpO2 (95.8 ± 2.6 vs. 95.2 ± 2.6%), flank (36.7 ± 0.4 vs. 36.5 ± 0.4°C), forearm (36.1 ± 0.6 vs. 35.5 ± 0.4°C) and leg (35.4 ± 0.7 vs. 34.7 ± 0.7°C) temperatures and narrower flank‐to‐forearm (0.6 ± 0.4 vs. 0.9 ± 0.3°C) and flank‐to‐leg (1.3 ± 0.6 vs. 1.8 ± 0.7°C) gradients, compared to those of the supine position. Similar differences were observed during AS. Conclusion: Perfusion index is a good non‐invasive estimate of tissue perfusion. Prone sleeping position is associated with a higher PI, possibly reflecting thermoregulatory adjustments in cardiovascular control. The effects of these position‐related changes may have important implications for the increased risk for sudden infant death syndrome in prone position.  相似文献   
994.

Introduction

Genetic factors predisposing individuals to cancer remain elusive in the majority of patients with a familial or clinical history suggestive of hereditary breast cancer. Germline DNA copy number variation (CNV) has recently been implicated in predisposition to cancers such as neuroblastomas as well as prostate and colorectal cancer. We evaluated the role of germline CNVs in breast cancer susceptibility, in particular those with low population frequencies (rare CNVs), which are more likely to cause disease."

Methods

Using whole-genome comparative genomic hybridization on microarrays, we screened a cohort of women fulfilling criteria for hereditary breast cancer who did not carry BRCA1/BRCA2 mutations.

Results

The median numbers of total and rare CNVs per genome were not different between controls and patients. A total of 26 rare germline CNVs were identified in 68 cancer patients, however, a proportion that was significantly different (P = 0.0311) from the control group (23 rare CNVs in 100 individuals). Several of the genes affected by CNV in patients and controls had already been implicated in cancer.

Conclusions

This study is the first to explore the contribution of germline CNVs to BRCA1/2-negative familial and early-onset breast cancer. The data suggest that rare CNVs may contribute to cancer predisposition in this small cohort of patients, and this trend needs to be confirmed in larger population samples.  相似文献   
995.
Background: This study was conducted to assess the dental treatment requirements of psychiatric patients in comparison with the non psychiatric patients admitted in the hospital.  相似文献   
996.
997.
998.
Summary— Cardiac arrhythmias and sudden death have been associated with both therapeutic and toxic doses of a number of cardiotropic and non-cardiac drugs. Generally the drug-induced electrocardiographic (ECG) alterations have been well described, whereas corresponding cellular electrophysiological effects are poorly documented or lacking. Taking into account the recent advances in the understanding of the mechanisms underlying arrhythmias and antiarrhythmic effects, suitable relationships can be established between ECG alterations and drug effects on cardiac action potential. Thus, a decrease in maximal upstroke velocity (Vmax) and membrane depolarisation leading to cellular inexcitability may slow conduction, prolong QRS interval duration and result in incessant wide QRS ventricular tachycardia. On the other hand, lengthening of the repolarisation phase and early afterdepolarisations (EADs) have been proposed as a mechanism for prolonged QT interval and subsequent Torsades de Pointes. A representative study aimed at detecting the arrhythmogenic potentiality of a drug is given, by examining carefully the concentration- and frequency-dependent effects of four neuroleptics (sultopride, droperidol, thioridazine and clozapine) on Purkinje fibers and comparing them with the reported iatrogenic arrhythmias. The results showed that 10 to 100 μM sultopride and 0.01 to 1 μM droperidol exerted “pure” class III effects. In addition, higher concentrations (3 to 30 μM) of droperidol reversed the prolonging effect on repolarisation concomitantly with a dose- and frequency-dependent decrease in Vmax, action potential amplitude and resting membrane potential (class I effects) resulting in cellular inexcitability at 30 μM. Similar class I effects were induced by thioridazine and clozapine concomitantly with a slight prolonging effect on final repolarisation (class la effects). In the presence of sultopride (30 and 100 μM) and droperidol (0.3 to 3 μM), EADs developed at plateau level. Their incidence, amplitude and number were influenced by extracellular K or Mg concentration, stimulation frequency, modification of Ca entry (by nifedipine or isoproterenol). These experimental results fit well with clinical data although they need further development to precise underlying ionic mechanisms. Therefore, in vitro studies should be considered before clinical prospects for future drug development.  相似文献   
999.
High ligation of the hernial sac is a hallowed and time-honoured concept in inguinal hernia repair and it is considered essential for preventing recurrence. However, this concept has been contested in recent reports. We conducted a prospective study of 186 cases of inguinal hernia repair. In 92 cases the sac was ligated at the neck and excised, in 94 cases the sac was not ligated at all but either simply inverted or excised without ligation. The type of repair was Bassini''s repair, Shouldice repair or Lichtenstein''s repair. Degree of post-operative pain was significantly less in those cases where sac was not ligated. There were no cases of recurrence in either group at 3 years follow up. Ligation of sac in inguinal hernia surgery is not only unnecessary and time consuming but also leads to increased post-operation pain. Recurrence is unaffected by not ligating the sac.Key Words: Hernial sac, Recurrence  相似文献   
1000.
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