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We have determined the complete cDNA and deduced amino acid sequences of the heavy chain, regulatory light chain and essential light chain which constitute the molecular structure of myosin from the striated adductor muscle of the scallop, Pecten maximus. The deduced amino acid sequences of P. maximus regulatory light chain, essential light chain and heavy chain comprise 156, 156 and 1940 amino acids, respectively. These myosin peptide sequences, obtained from the most common of the eastern Atlantic scallops, are compared with those from three other molluscan myosins: the striated adductor muscles of Argopecten irradians and Placopecten magellanicus, and myosin from the siphon retractor muscle of the squid, Loligo pealei. The Pecten heavy chain sequence resembles those of the other two scallop sequences to a much greater extent as compared with the squid sequence, amino acid identities being 97.5% (A. irradians), 95.6% (P. magellanicus) and 73.6% (L. pealei), respectively. Myosin heavy chain residues that are known to be important for regulation are conserved in Pecten maximus. Using these Pecten sequences, we have overexpressed the regulatory light chain, and a combination of essential light chain and myosin heavy chain fragment, separately, in E. coli BL21 (DE3) prior to recombination, thereby producing Pecten regulatory domains without recourse to proteolytic digestion. The expressed regulatory domain was shown to undergo a calcium-dependent increase (7%) in intrinsic tryptophan fluorescence with a mid-point at a pCa of 6.6.  相似文献   
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A Kumar  N Kumar  J C Vij  S K Sarin    B S Anand 《Gut》1987,28(2):150-155
To determine the optimum dose of ispaghula husk in patients with irritable bowel syndrome (IBS) and to assess the correlation, if any between the relief in patients' symptoms and the whole gut transit time, and the increase in stool weight, a two part study was carried out. In part 1, 14 male patients were given ispaghula husk in increasing doses of 10 g, 20 g, and 30 g a day for a duration of 17 days each (14 days of study period + three days of stool collection). Ten patients completed the trial. The symptom score improved significantly with all the three doses of ispaghula. Both 20 g and 30 g doses of ispaghula were superior to the 10 g dose but there was no significant difference between the 20 g and 30 g doses. There was a significant (p less than 0.001) increase in the daily stool weight with 10 g dose of fibre with further significant increases with the 20 g and 30 g doses. A positive correlation was seen between the improvement in the symptom score and the increase in stool weight with the 10 g dose of ispaghula but not with the 20 g and 30 g doses. Whole gut transit time remained fairly constant throughout the study period and there was no relationship with either the dose of ispaghula, the alteration in stool weight, or the improvement in the patients symptoms. Ten patients completed part 2 of the study in which ispaghula husk was given in the same dose (10 g, 20 g, and 30 g) but in a random order and with a "washout" period of one week between individual doses. Again all the three doses of ispaghula produced a significant improvement in the symptoms; 20 g and 30 g doses were equally effective and both were significantly superior to the 10 g dose. Assessed individually, all the three symptoms improved significantly; improvement in constipation and pain abdomen was more pronounced than diarrhoea. It is concluded that the optimum dose of ispaghula husk in irritable bowel syndrome is 20 g per day. There is some correlation between the increase in stool weight and the improvement in symptom score but the whole gut transit time remains unchanged despite alterations in stool weight and patients' symptoms.  相似文献   
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Background/Purpose of the StudyC-arm-guided biopsy is a safe and effective technique for evaluating TB spine and is useful in planning therapy. The purpose of this study was to find a correlation between clinically and radiologically suspected TB spine and C-arm image-guided biopsy-proven cases and to study the complications encountered.MethodsAfter evaluating the clinical, laboratory, X-ray and MRI findings, 92 patients with provisionally diagnosed tubercular spine were subjected to C-arm image-guided biopsy.ResultsAmong our 92 cases, histopathology was positive in 55 cases (59.78%). Out of these 55 histologically positive cases, CBNAAT was positive in 42 cases and negative in the rest 13 cases. Overall, among the 92 cases, CBNAAT was positive in 51(55.43%) of cases, and out of these, histopathology turned out to be positive in 42 of cases. Out of 41 cases with negative CBNAAT, histopathology was suggestive of tuberculosis in 13. The strength of agreement between CBNAAT and histopathology was statistically significant (p < 0.0001; kappa = 0.511). No complication such as bleeding, nerve/cord injury, infection, injury to aorta or pneumothorax was encountered during and after the C-arm biopsy in any case.ConclusionC-arm image-guided biopsy is reasonably accurate and should be used as a tool for diagnosis of TB spine. We recommend histopathological examination as a key component for the diagnosis of TB spine, as it is precise and consumes relatively shorter time. CBNAAT is more rapid but is not a substitute for histopathology for spine TB diagnosis.  相似文献   
5.
Virtually all forensic experts deal not only with criminal, suspicious, accidental and suicidal deaths, but are also confronted with a wide range of deaths where a significant natural element is revealed at autopsy. The assaulted victim that dies suddenly or unexpectedly from a stroke during or immediately succeeding the receipt of some non-fatal injuries, or otherwise suffers a clinically unexplained death, can pose far greater difficulties over causation than a gun-shot or a stabbing. This paper presents an analysis of the problem and an approach for determining the cause of death in cases of concurrent trauma with heart disease, and in cases with a substantial natural element of disease but exclusion of trauma. Relevant cases with history, autopsy findings, histopathological findings and toxicological findings are presented in order to illustrate the issue from a practical angle.  相似文献   
6.
Palliative care (PC) training and experience of United States (US) adult nephrology fellows was not known. It was also not clear whether nephrology fellows in the US undergo formal training in PC medicine during fellowship. To gain a better understanding of the clinical training and experience of US adult nephrology fellows in PC medicine, we conducted a national survey in March 2012. An anonymous on-line survey was sent to US adult nephrology fellows via nephrology fellowship training program directors. Fellows were asked several PC medicine experience and training questions. A total of 105 US adult nephrology fellows responded to our survey (11% response rate). Majority of the respondents (94%) were from university-based fellowship programs. Over two-thirds (72%) of the fellows had no formal PC medicine rotation during their medical school. Half (53%) of the respondents had no formal PC elective experience during residency. Although nearly 90% of the fellows had a division or department of PC medicine at their institution, only 46.9% had formal didactic PC medicine experience. Over 80% of the respondent's program did not offer formal clinical training or rotation in PC medicine during fellowship. While 90% of the responding fellows felt most comfortable with either writing dialysis orders in the chronic outpatient unit, seeing an ICU consult or writing continuous dialysis orders in the ICU, only 35% of them felt most comfortable “not offering” dialysis to a patient in the ICU with multi-organ failure. Nearly one out of five fellows surveyed felt obligated to offer dialysis to every patient regardless of benefit. Over two-thirds (67%) of the respondents thought that a formal rotation in PC medicine during fellowship would be helpful to them. To enhance clinical competency and confidence in PC medicine, a formal PC rotation during fellowship should be highly considered by nephrology training community.  相似文献   
7.
Traumatic palsy of the descending branch of the posterior interosseous nerve (PIN) is rare. Traumatic palsy usually involves the entire PIN around the elbow, leading to finger drop with loss of extension of all fingers and thumb. In the literature, to the best of our knowledge, only one case of traumatic palsy of the descending branch of the PIN due to penetrating injury is reported [1]. We report a neglected, rare case with complete loss of thumb extension and weakness in index finger extension following penetrating injury to the forearm. Our report shows that to diagnose the lesion site in partial PIN palsy, detailed knowledge of the PIN branching pattern is necessary.  相似文献   
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Introduction

The impact of the dose and fractionation of thoracic radiotherapy on the risk of developing brain metastasis (BM) has not been evaluated prospectively in limited stage SCLC patients receiving prophylactic cerebral irradiation (PCI).

Methods

Data from patients treated with PCI from the CONVERT trial were analyzed.

Results

Four hundred forty-nine of 547 patients (82%) received PCI after completion of chemoradiotherapy. Baseline brain imaging consisted of computed tomographic scans in 356 of 449 patients (79%) and magnetic resonance imaging in 83 of 449 (18%) patients. PCI was delivered to 220 of 273 participants (81%) in the twice-daily (BD) group and 229 of 270 in the once-daily (OD) group (85%; p = 0.49). Total median PCI dose was 25 Gy in both the BD and OD groups (p = 0.74). In patients who received PCI, 75 (17%) developed BM (35 [8%] in OD and 40 [9%] in BD) and 173 (39%) other extracranial progression. In the univariate analysis, gross tumor volume (GTV) was associated with an increased risk of BM (p = 0.007) or other radiological progression events (p = 0.006), whereas in a multivariate analysis both thoracic GTV (tGTV) and ECOG performance score were associated with either progression type. The median overall survival (OS) of patients treated with PCI was 29 months. In the univariate analysis of OS, PCI timing from end of chemotherapy, weight loss of more than 10%, and tGTV were prognostic factors associated with OS. In the multivariate analysis, only tGTV was associated with OS. Delay between end of chemotherapy and PCI was not associated with OS.

Conclusions

Patients receiving OD or BD thoracic radiotherapy have the same risk of developing BM. Larger tumors are associated with a higher risk of BM.  相似文献   
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