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91.
A simple radiochemical method was developed for determining the ATP-citrate lyase activity in mammalian spermatozoa. The determination of enzyme activity was followed by the measurement of the incorporation of the [1-14C]acetyl group from [1,5-14C]citrate into [1-14C]acetylcoenzyme A (ACoA). Separation of 14C-labeled ACoA from the reactants and their products was achieved by rapid anion exchange chromatography. The optimum pH was 6.4 for rat spermatozoal ATP-citrate lyase. The activity was not altered by dithiothreitol. MgCl2 (l0mM) caused a 50 per cent inhibition in the enzyme activity. ATP-citrate lyase activities in rat and human spermatozoa were 154 ± 14 and 90 ± 12 nmoles of ACoA formed/mg of protein/5 min. Citrate may serve as an acetyl source for acetylcholine formation by spermatozoa.  相似文献   
92.
The serum of a case of hyperglobulinaemia with negative thymol and zinc sulphate turbidity reactions was studied. The serum when added to pathological sera with high turbidity values brought about a marked reduction in the original turbidity values. Also, the serum did not give the usual copper proteinate precipitate when added to copper sulphate solutions. The anomalous protein fraction responsible for the above properties was isolated from the γ globulins by precipitation at 28% saturation with ammonium sulphate. It was found to be neither a macroglobulin (Waldenstrom's), a cryoglobulin, nor a collagen protein. Its occurrence in the very γ globulin fraction which is responsible for many of the turbidity reactions is of great significance in the interpretation of these tests. It is suggested that the normal turbidity and flocculation reactions reported in some cases of multiple myelomatosis might be due to some such anomalous proteins.  相似文献   
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BACKGROUND AND PURPOSE: Formation of kidney stones is still not understood but is hypothesized to be associated with the vitamin D receptor gene (VDR). In order to assess the eventual role of VDR start-codon FokI polymorphism in stone formation, we evaluated the association between calcium stone disease and this polymorphism in a North Indian population. PATIENTS AND METHODS: A control group comprised of 166 healthy individuals (age range 22-58 years) and a group of 138 patients with calcium oxalate stones (age range 21-72 years) were examined. The polymorphism was detected using polymerase chain reaction-based restriction analysis. An unexcisable length of 265 bp (CC) and two fragments of 169 bp and 96 bp (TT) were obtained by FokI restriction digestion. RESULTS: There was a statistically significant difference between the control and patient groups (X2 test, P<0.001) for the genotype of the VDR FokI start-codon polymorphism. The odds ratio (with 95% CI) for the C allele in those at risk of stone disease was 1.654 (1.041, 2.628). The VDR frequency distribution was also statistically significant (P<0.001) in case of male sex. The frequency distribution for this genetic polymorphism was not statistically different in normocalciuric and hypercalciuric stone patients (P=0.355). CONCLUSION: The VDR FokI polymorphism may be a good candidate for a marker for calcium oxalate-stone disease. These findings may contribute a small piece to the understanding of the pathogenesis of urinary calculi.  相似文献   
96.
Introduction Atherosclerotic coronary artery disease is in an increasing trend in India. With the advancement of non-surgical methods of revascularisation, the patients coming for surgery are of less attractive anatomy. The role of coronary endarterectomy along with coronary artery bypass grafting for a selected group of these patients is quite promising. Materials and Methods From March 2000 to March 2005, out of 362 CABGs performed, 42 patients had undergone coronary endarterectomy. The age range being from 35 to 76 years, M: F is 38∶4 Hypertension was present in 26 (61%), diabetes mellitus in 20 (47.6%), smoking in 26 (61%) and dyslipidemia in 12 (28.5%) cases. Old myocardial infarction was present in 52.3% cases, unstable angina in 16.6%, stable angina in 23.8% and cardiogenic shock in 7.1% cases. All cases had undergone coronary artery bypass grafting with endarterectomy. Out of 18 LAD endarterectomies 17 cases LIMA was used as onlay patch. Result The average number of grafts anastomosed was 3.7. Single-vessel endarterectomy was done in 37, double vessel in 4 and four vessel in one case. LAD endarterectomy was done in 18, RCA in 12, diagonal in 10, intermediate in 1 and marginals in 8 cases. Postoperatively 3 patients had arrhythmia, two perioperative MI, one recurrent angina and one congestive cardiac failure (CCF). There was 2 (4.76%) mortality. Conclusion Hypertension and smoking are major risk factors. LAD is the most common artery requiring endarterectomy. Usage of LIMA following endarterectomy of LAD is quite satisfactory and short term results are encouraging.  相似文献   
97.
AIM: To 1) compare post-wash and post-thaw parameters of sperm processed with PureSperm density gradient technique and swim-up method; and 2) test the efficacy of two commonly available density gradient media PureSperm and ISolate. METHODS: This prospective study used semen specimens from 22 patients. Specimens from nine patients were processed by both PureSperm density gradient and swim-up method. These specimens were then cryopreserved. Thirteen specimens were processed by both PureSperm (40 % and 80 %) and Isolate (50 % and 90 %) double density gradient techniques. The two fractions processed by both PureSperm and swim-up were analyzed for post-wash sperm characteristics. Post-thaw analysis was done after 24 hours. Sperm fractions obtained after processing with PureSperm and ISolate were compared for post-wash sperm characteristics and ROS levels. Results: Specimens prepared with PureSperm had significantly higher median total motile sperm counts (TMSC) (32.2 x 10(6) vs. 17.6 x 10(6)), recovery rates (69.2 % vs. 50.0 %), and longevity at 4 hours (83.0 % vs. 55.0 %) compared to specimen prepared by swim-up. Post-thaw specimens also had a higher recovery and longevity at 4 hours with PureSperm as compared to the swim-up. Semen specimens processed by PureSperm had significantly higher total sperm count, TMSC, and percentage recovery rates (30.0 % vs. 19.7 %) than ISolate. CONCLUSION: Semen quality is better preserved in fresh and cryopreserved semen prepared with PureSperm density gradient compared to swim-up. A significant enrichment of sperm is observed with PureSperm compared to ISolate. Higher recovery rates of mature motile sperm obtained after PureSperm sperm preparation may be beneficial for successful ART.  相似文献   
98.
In view of the recent discussion concerning the safety of combined therapy with haloperidol and lithium carbonate,1,2 we wish to present our experience with 28 patients who received this combination of drugs for the treatment of acute mania.  相似文献   
99.
Cardiovascular disease poses a major health care burden in the Western world. Following myocardial injuries, ventricular remodelling and dysfunction ensue, which can eventually culminate in heart failure. An important event in left ventricular (LV) remodelling is alteration of the extracellular matrix (ECM) integrity, the structural network that interconnects the myocardial components. The critical role of ECM remodelling in cardiac dilation and heart failure was recognized more than a decade ago, and the molecular factors responsible for this process are now being explored. Abnormal ECM turnover is primarily brought about by an imbalance in the activity of matrix metalloproteinases (MMPs) that degrade ECM components, and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs). Here we provide an overview of composition of the cardiac ECM, and alterations in ECM regulatory proteins, MMPs and TIMPs, in human heart disease. We also discuss the role of TIMPs, MMPs, and a disintegrin and metalloproteinase (ADAMs) enzymes in cardiac development and function as learned through genetically altered mouse models.  相似文献   
100.
OBJECTIVE: The purpose of this study was to identify residual symptoms in a sample of older adults treated for major depression and compare individual symptoms present at baseline with those at three months by remission status. METHODS: The sample was comprised of 229 patients with DSM-IV major depression who were participants in the NIMH Mental Health Clinical Research Center at Duke University. Symptoms were measured using the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: At three months, 86 patients (37.6%) had remitted, or had a MADRS score less than or equal to 9. In the remitted group, the most frequently reported symptoms at three months were inner tension and lassitude. Among nonremitters, the most frequently reported symptoms were reported and apparent sadness, as well as lassitude and inner tension. In the sample as a whole, the symptoms most likely to be present at baseline but not three months were pessimistic and suicidal thoughts, while the most frequently reported emergent symptoms were reduced appetite and inner tension. Patients were much more likely to no longer have a particular symptom than to acquire a new symptom. Overall, the symptoms present at three months were not severe in either group. CONCLUSIONS: In older adults treated for major depression, residual symptoms at three months may include emergent symptoms as well as persistent symptoms, and are likely to include symptoms of anxiety as well as sadness. These findings have clinical implications for the treatment of late-life depression.  相似文献   
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