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71.
72.
Pulse sequences are presented for the measurement of3JCC and3JNC scalar couplings for allC containing residues in15N,13C uniformly labeled proteins. The methodsdescribed are based on quantitative J correlation spectroscopy pioneered byBax and co-workers [Bax et al. (1994) Methods Enzymol., 239, 79–105].The combination of 3JCC and3JNC scalar coupling constants allows theassignment of discrete rotameric states about the 1 torsion angle in cases where such states exist or, alternatively,facilitates the establishment of noncanonical 1conformations or the presence of rotameric averaging. The methods areapplied to a 1.5 mM sample of staphylococcal nuclease.  相似文献   
73.
OBJECTIVE--To determine the causes of non-attendance at new outpatient appointments. DESIGN--Case-control study of non-attenders and attenders. SETTING--Outpatient department of a general hospital. SUBJECTS--All non-attenders (n = 277) for first outpatient appointments in six specialties during a three month period were included. Controls (n = 135) were the attenders who followed every second non-attender; thus they attended the same consultant on the same day that the non-attenders were expected. INTERVENTIONS--None. MEASUREMENTS AND MAIN RESULTS--Information on the clinical problem, difficulties in attending the hospital, and reasons for non-attendance from the questionnaire were coded and classified. Non-attenders had received shorter notice of their appointment than attenders (14% v 1% had received three days'' notice or less). There were small differences in the seriousness of patients'' clinical condition. CONCLUSIONS--Client factors are less important than aspects of the service in explaining non-attendance at outpatient appointments.  相似文献   
74.
We tested the hypothesis that 1-desamino-8-D-arginine vasopressin (DDAVP), a V2-receptor agonist, could inhibit the diuresis induced by water immersion in humans. Water and electrolyte excretion, plasma atrial natriuretic factor concentration, and plasma aldosterone concentration were measured initially and after 3 h of water immersion in 13 healthy sodium-replete men given either placebo or 20 micrograms of intranasal DDAVP. Guanosine 3',5'-cyclic monophosphate and urea excretion and urine osmolality were also determined. DDAVP inhibited the diuresis induced by water immersion in men: 758 +/- 168 (SE) ml/3 h in the placebo group vs. 159 +/- 28 ml/3 h in the DDAVP group (P less than 0.05). After 3 h of water immersion, plasma atrial natriuretic factor concentrations were increased from 11 +/- 2 to 20 +/- 4 pg/ml in the placebo group and from 14 +/- 2 to 33 +/- 4 pg/ml in the DDAVP group (P less than 0.05). Plasma aldosterone concentrations were decreased from 98 +/- 18 to 45 +/- 6 pg/ml in the placebo group (P less than 0.05) and from 54 +/- 17 to 25 +/- 5 pg/ml in the DDAVP group (P less than 0.05). Despite these changes in aldosterone and atrial natriuretic factor concentrations, which should increase sodium excretion, DDAVP decreased the natriuresis induced by water immersion in humans: 56 +/- 8 meq Na+/3 h in the placebo group vs. 36 +/- 6 meq Na+/3 h in the DDAVP group (P less than 0.05). DDAVP may be used to prevent the diuresis associated with central redistribution of blood volumes that occur during water immersion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Heterofermentative lactobacilli have been isolated from kefir grains obtained from four different sources. A number of these isolates ferment only L-arabinose and gluconate and are similar to the species 'Lactobacillus desidiosus'. The DNA of these isolates, however, have 85-109% homology with 'L. caucasicus' NCDO 190 which is now regarded as L. kefir. The relationship between these strains is discussed.  相似文献   
77.
OBJECTIVE--To examine the causes of non-admission to hospital. DESIGN--Validation of published rates of non-admission by examination of medical records, followed by a case-control study of non-attenders (cases) and attenders (controls). SETTING--General hospital. SUBJECTS--246 Patients (cases in the case-control study) booked for admissions in four specialties (general surgery, gynaecology, otorhinolaryngology, and trauma and orthopaedics) during April, May, and June 1987 who were not admitted for reasons that seemed to be attributable to the patients. Controls comprised 167 patients admitted to the same specialty on the same day. RESULTS--The validation of administrative records indicated that it is unusual for patients to fail to present for admission without advising the hospital beforehand; this occurred in only 1-3% of all bookings. Information on the circumstances of non-admission and clinical and personal details were collected by means of a six page questionnaire completed by the patients. The case-control study showed that those not admitted were younger and had been on the waiting list longer. Otherwise only small differences were found in the social and clinical characteristics. CONCLUSIONS--Despite a common tendency to blame patients for non-admission, factors due to patients are fairly unimportant.  相似文献   
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79.
Noncoding RNAs have recently been identified as essential components of the nuclear suborganelles called paraspeckles. This finding will facilitate our understanding of the molecular dynamics and physiological role of these enigmatic macromolecular structures.  相似文献   
80.
A novel series of pyrazole sEH inhibitors is reported. Lead optimization efforts to replace the aniline core are also described. In particular, 2-pyridine, 3-pyridine and pyridazine analogs are potent sEH inhibitors with favorable CYP3A4 inhibitory and microsomal stability profiles.  相似文献   
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