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21.
The authors examine weight gains associated with smoking cessation in the Lung Health Study (1986-1994) over a 5-year follow-up period. A cohort of 5,887 male and female smokers in the United States and Canada, aged 35-60 years, were randomized to either smoking intervention or usual care. Among participants who achieved sustained quitting for 5 years, women gained a mean of 5.2 (standard error, 5.0) kg in year 1 and a mean of 3.4 (standard error, 5.5) kg in years 1-5. Men gained a mean of 4.9 (standard error, 4.9) kg in year 1 and a mean of 2.6 (standard error, 5.8) kg in years 1-5. In regression analyses, smoking-change variables were the most potent predictors of weight change. Participants going from smoking to quit-smoking in a given year had mean weight gains of 2.95 kg/year (3.61%) in men and 3.09 kg/year (4.69%) in women. Over 5 years, 33% of sustained quitters gained > or = 10 kg compared with 6% of continuing smokers. Also among sustained quitters, 7.6% of men and 19.1% of women gained > or = 20% of baseline weight; 60% of the gain occurred in year 1, although significant weight gains continued through year 5. The average gains and the high proportions of sustained and intermittent quitters who gained excessive weight suggest the need for more effective early interventions that address both smoking cessation and weight control.  相似文献   
22.
Electron microscopy of toad (Bufo marinus) muscle fixed without relaxing after a single eccentric contraction at muscle lengths greater than optimum showed over-stretched half-sarcomeres in sufficient numbers to account for more than half of the imposed stretch. Such sarcomeres were absent in another muscle fixed without relaxing after an isometric contraction at the same length and largely absent in a third muscle that underwent eccentric contraction at muscle lengths less than optimum. This provides direct evidence in support of the hypothesis that lengthening of muscles at long length involves lengthening of a few half sarcomeres to beyond filament overlap, while most half sarcomeres are extended much less than in proportion to muscle extension.  相似文献   
23.
A new class of potent, orally active phenyl piperazine-based GH secretagogues have been discovered from attempts to mimic the arrangement of the phenyl substituent in the spiroindanyl piperidine and spiroindoline sulfonamide privileged structures of 4 and 1, respectively. The best of these compounds, 18 (EC50 = 2.8 nM) is nearly as potent as MK-0677 for releasing GH from rat pituitary cells.  相似文献   
24.
Evaluating behavioral interventions for HIV prevention   总被引:1,自引:0,他引:1  
We report a case of primary amyloidosis affecting the kidney and presenting as a renal infarction on computed tomography and ultrasound examination. To our knowledge, it is the first case in the radio-logical literature with these imaging characteristics.  相似文献   
25.
The ever-increasing number of proteins identified as belonging to the family of small heat-shock proteins (shsps) and alpha-crystallins enables us to reassess the phylogeny of this ubiquitous protein family. While the prokaryotic and fungal representatives are not properly resolved, most of the plant and animal shsps and related proteins are clearly grouped in distinct clades, reflecting a history of repeated gene duplications. The members of the shsp family are characterized by the presence of a conserved homologous "alpha-crystallin domain," which sometimes is present in duplicate. Predictions are made of secondary structure and solvent accessibility of this domain, which together with hydropathy profiles and intron positions support the presence of two similar hydrophobic beta-sheet-rich motifs, connected by a hydrophilic alpha-helical region. Together with an overview of the newly characterized members of the shsp family, these data help to define this family as being involved as stable structural proteins and as molecular chaperones during normal development and induced under pathological and stressful conditions.  相似文献   
26.
A new experimental model of a vascular carrier to prefabricate a "secondary" island flap, the popliteal musculovascular pedicle, was developed in the rat. Using quantitative skin-surface fluorometry 30 minutes after sodium fluorescein injection and a flap survival area in the prefabricated 8 x 2.5-cm abdominal composite island flap, we compared the revascularization ability of our muscular carrier to nonrevascularized controls: the skeletonized arteriovenous pedicle and the fasciovascular pedicle. The free composite graft with no vascular carrier exhibited near-total necrosis. The skeletonized vascular pedicle demonstrated 15.2% +/- 7.8% perfusion of normal skin on dye fluorescence index measurements and 50% flap survival. The fasciovascular pedicle exhibited better revascularization, with a dye fluorescence index of 36.2 +/- 15.5 (p < 0.01) and 90% +/- 10% flap survival (p < 0.001). India ink injection study and histological examination of our model provided visual evidence of revascularization from the musculovascular pedicle, along with preservation of the carrier's muscular architecture. The musculovascular pedicle is a reliable carrier for making new, vascularized composite flaps.  相似文献   
27.
This paper describes the implementation and evaluation of a nonsanction seat belt law enforcement program in two experimental communities of contrasting size in a state with a mandatory belt law. The main ingredients of the program were seat belt "salutes," public information and education, and limited use of inexpensive economic incentives. Driver shoulder belt use data collected before, during, and after the experimental programs, compared to similar data collected in a comparison community, showed the approach to be effective. While standard seat belt enforcement activities without incentives have been shown to be effective, many police departments, especially in smaller communities, are reluctant to make wholesale increases in seat belt citations. Although requiring some additional level of manpower and resources, a nonsanction approach to seat belt law enforcement can provide an alternate way of increasing belt use in these communities.  相似文献   
28.
Necrotizing enterocolitis (NEC) usually occurs in low birth weight infants who have had perinatal stress, and the mortality remains significant. There are a few reports of NEC in the postoperative period, especially in young infants. Nine neonates developed NEC following operations and form the basis of this report. The interval between operation and the diagnosis of NEC varied from 3 days to 4 mo. The surgical lesions included one case each of esophageal atresia, tetralogy of Fallot, supralevator rectal atresia with rectourethral fistula, and multiple intestinal atresias. Three babies had gastroschisis and two had "apple peel" intestinal atresia. Only 3 of the 9 survived. The usual clinical findings of NEC, abdominal distention, bile stained gastric residuals and diarrhea (with or without blood), can occur in the postoperative period without NEC and are, therefore, not reliable diagnostic signs. Significant changes in the clinical course of these babies occurred from 7 hr to 5 days before the diagnosis was established. In these patients the roentgen findings that established the diagnosis of NEC included intestinal ileus, pneumatosis intestinalis, and portal vein gas. Pneumatosis intestinalis and portal vein gas were the most reliable diagnostic signs, but appeared relatively late in the course of the disease. In one case pneumatosis was seen only in retrospect. None of the patients had definite pneumoperitoneum. Awareness of NEC as a potential postoperative complication may result in early recognition, treatment and survival.  相似文献   
29.
108 tendons of the m. extensor hallucis longus were examined with a tensile testing machine within 36 h after death. The specimen were kept at a resting length of 20 mm. After the "steady state" was reached by cyclic loading, the tendons were stretched up to a maximum load of 18 kp, then deloaded to a certain level and after that the elongation was kept constant. At high loading level the tension of the tendon decreases with time (relaxation). At medium and low loading level the tension increases slightly (mechanical recovery). Between that two regions there is a certain load, where the tension will not change with time (isorheological point). The position of the isorheological point depends on the velocity of the elongation. At low velocity (2 mm/min) the isorheological point is situated at 70%, at high velocity (12 mm/min) at 60% of the maximum load. One will find the maximum relaxation, when no deloading occurs. The mechanical recovery, however, has its maximum at 5--25% of the maximum load. But when the tendon is totally deloaded, there seems to occur no recovery. The maximum relaxation is 5 to 6 times larger than the maximum recovery. Supposingly the relaxation- and recovery-processses will happen at the same time but with different intensity depending on the loading level. At least the relaxation-process consists of different relaxation components with different relaxation times. This will explain the phenomenon of a "secondary relaxation": After a long time of registration the recovery will turn into a slight relaxation.  相似文献   
30.
The objective of the research described here was to develop a set of predictive models that would be used to show the performance of hydroxypropylcellulose as a pharmaceutical tablet binder. A statistically designed set of experiments was used to relate tablet formulation to functionality. It was found that the binder level affected both hardness and dissolution time. Useful predictive models were generated for tablet hardness and dissolution time as a function of the binder or binder-drug ratio. The optimal formulation can be predicted from this study, and will depend upon the combination of desired hardness and the dissolution time for a particular drug.  相似文献   
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