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11.
OBJECTIVE--To compare the efficacy and tolerability of hydrochlorothiazide, sustained release verapamil, and their combination in patients with mild to moderate hypertension. DESIGN--Randomised multicentre trial of 48 weeks'' duration with a double blind comparison of hydrochlorothiazide and verapamil followed by an open trial of combined treatment for patients not achieving the target diastolic blood pressure (less than 90 mm Hg) during treatment with a single drug. SETTING--Outpatient departments in 10 clinics and 10 private practices of general practitioners or internists. PATIENTS--369 Hypertensive patients with a diastolic blood pressure of 95-120 mm Hg during a placebo run in period of two weeks. INTERVENTIONS--Initial treatment consisted of 12.5 mg hydrochlorothiazide (n = 187) or 120 mg sustained release verapamil (n = 182) once daily (regimen I). If the target diastolic blood pressure of less than 90 mm Hg was not achieved within four weeks doses were increased to 25 mg hydrochlorothiazide or 240 mg verapamil once (regimen II) and twice daily (regimen III). Patients not achieving target blood pressure were given the combination of hydrochlorothiazide and verapamil--that is, 25 and 240 mg once (regimen IV) and twice daily (regimen V). MAIN OUTCOME MEASURE--Blood pressure determined with a device permitting automatic repeated measurements with printouts. RESULTS--After eight weeks of treatment with a single drug 76 out of 178 (43%) and 101 out of 175 (58%) patients achieved the target blood pressure with hydrochlorothiazide and verapamil, respectively. During follow up until 48 weeks patients treated with verapamil reached the target blood pressure more often and at lower doses and were less likely to switch to combination treatment than patients randomised to hydrochlorothiazide treatment. Adding verapamil to hydrochlorothiazide was more effective than the addition of hydrochlorothiazide to verapamil. At the end of the study 42 out of 169 (25%) and 73 out of 163 (45%) patients initially randomised to hydrochlorothiazide and verapamil, respectively, were at target blood pressure without combination treatment. After adding verapamil to hydrochlorothiazide or hydrochlorothiazide to verapamil an additional 58 (34%) and 29 (18%) patients reached the target blood pressure, respectively. Altogether 92 out of 332 (28%) patients failed to achieve target blood pressure with regimen V. There were four, 10, seven, and seven withdrawals due to possible adverse effects to treatment with hydrochlorothiazide, verapamil, combining verapamil with hydrochlorothiazide, and combining hydrochlorothiazide with verapamil, respectively. CONCLUSIONS--In doses currently used in antihypertensive treatment verapamil was more effective than hydrochlorothiazide as a single agent and in combination in mild to moderate hypertension, whereas withdrawal rates caused by side effects possibly related to treatment were similar.  相似文献   
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Two different genes encoding class II chitinases from peanut (Arachis hypogaea L. cv. NC4), A.h.Chi2;1 and A.h.Chi2;2, have been cloned. In peanut cell suspension cultures, mRNA levels of A.h.Chi2;2 increased after ethylene or salicylate treatment and in the presence of conidia from Botrytis cinerea. The second gene, A.h.Chi2;1, was only expressed after treatment with the fungal spores. Transgenic tobacco plants containing the complete peanut A.h.Chi2;1 gene exhibited essentially the same expression pattern in leaves as observed in peanut cell cultures. Expression characteristics of transgenic tobacco carrying a promoter-GUS fusion of A.h.Chi2;1 are described.  相似文献   
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The Djungarian hamster (Phodopus sungorus) is a markedly photoperiodic rodent which exhibits daily torpor under short photoperiod. Normative data were obtained on vigilance states, electroencephalogram (EEG) power spectra (0.25–25.0 Hz), and cortical temperature (TCRT) under a 168 h light-dark schedule, in 7 Djungarian hamsters for 2 baseline days, 4 h sleep deprivation (SD) and 20 h recovery.During the baseline days total sleep time amounted to 59% of recording time, 67% in the light period and 43% in the dark period. The 4 h SD induced a small increase in the amount of non-rapid eye movement (NREM) sleep and a marked increase in EEG slow-wave activity (SWA; mean power density 0.75–4.0 Hz) within NREM sleep in the first hours of recovery. TCRT was lower in the light period than in the dark period. It decreased at transitions from either waking or rapid eye movement (REM) sleep to NREM sleep, and increased at the transition from NREM sleep to waking or REM sleep. After SD, TCRT was lower in all vigilance states.In conclusion, the sleep-wake pattern, EEG spectrum, and time course of TCRT in the Djungarian hamster are similar to other nocturnal rodents. Also in the Djungarian hamster the time course of SWA seems to reflect a homeostatically regulated process as was formulated in the two-process model of sleep regulation.Abbreviations EEG electroencephalogram - EMG electromyogram - N NREM sleep - NREM non-rapid eye movement - R REM sleep - REM rapid eye movement - SD sleep deprivation - SWA slow-wave activity - TCRT cortical temperature - TST total sleep time - VS vigilance state - W waking  相似文献   
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Aim

Land use is the most pervasive driver of biodiversity loss. Predicting its impact on species richness (SR) is often based on indicators of habitat loss. However, the degradation of habitats, especially through land-use intensification, also affects species. Here, we evaluate whether an integrative metric of land-use intensity, the human appropriation of net primary production, is correlated with the decline of SR in used landscapes across the globe.

Location

Global.

Time period

Present.

Major taxa studied

Birds, mammals and amphibians.

Methods

Based on species range maps (spatial resolution: 20 km × 20 km) and an area-of-habitat approach, we calibrated a “species–energy model” by correlating the SR of three groups of vertebrates with net primary production and biogeographical covariables in “wilderness” areas (i.e., those where available energy is assumed to be still at pristine levels). We used this model to project the difference between pristine SR and the SR corresponding to the energy remaining in used landscapes (i.e., SR loss expected owing to human energy extraction outside wilderness areas). We validated the projected species loss by comparison with the realized and impending loss reconstructed from habitat conversion and documented by national Red Lists.

Results

Species–energy models largely explained landscape-scale variation of mapped SR in wilderness areas (adjusted R2-values: 0.79–0.93). Model-based projections of SR loss were lower, on average, than reconstructed and documented ones, but the spatial patterns were correlated significantly, with stronger correlation in mammals (Pearson's r = 0.68) than in amphibians (r = 0.60) and birds (r = 0.57).

Main conclusions

Our results suggest that the human appropriation of net primary production is a useful indicator of heterotrophic species loss in used landscapes, hence we recommend its inclusion in models based on species–area relationships to improve predictions of land-use-driven biodiversity loss.  相似文献   
18.
 CD44 isoforms have been implicated in tumor progression and metastasis formation. This study presents a thorough immunohistochemical analysis of CD44 standard and isoform expression in normal human skin appendages and epidermis applying monoclonal antibodies against CD44s, CD44v3, -v4, -v5, -v6, and -v9. An improved immunohistochemical protocol with microwave-based antigen retrieval in paraffin sections and heavy metal amplification of the diaminobenzidine reaction product provided enhanced resolution and sensitivity as compared to studies on frozen sections. The hair follicle, the seborrheic and eccrine sweat glands were strongly positive for all CD44 isoforms studied. In the latter, the clear cells but not the dark (intercalated) cells were positive. The sudoriferous ducts adjacent to the glands were weakly positive for all CD44 isoforms and strongly positive near the skin surface. In the apocrine glands, the basal cells showed only a moderate positivity. The myoepithelial cells expressed only CD44s. In the epidermis, all CD44 isoforms were detectable, with strongest CD44 immunostaining in the lower third of the stratum spinosum and weaker staining in the stratum basale and the upper two-thirds of the stratum granulosum. The stratum granulosum and corneum were unreactive. Thus, a regional and cell type-specific CD44 expression was revealed. Accepted: 10 May 1996  相似文献   
19.
Human immunodeficiency virus Nef protein accelerates virulent progression of AIDS by its interaction with specific cellular proteins involved in cellular activation and signal transduction. Here we report the purification and crystallization of the conserved core of HIV-1LAI Nef protein in the unliganded form and in complex with the wild-type SH3 domain of the P59fyn protein-tyrosine kinase. One-dimensional NMR experiments show that full-length protein and truncated fragment corresponding to the product of HIV-1 protease cleavage have a well-folded compact tertiary structure. The ligand-free HIV-1 Nefcore protein forms cubic crystals belonging to space group P23 with unit cell dimensions of a = b = c = 86.4 A. The Nef-Fyn SH3 cocrystals belong to the space group P6(1)22 or its enantiomorph, P6(5)22, with unit cell dimensions of a = b = 108.2 A and c = 223.7 A. Both crystal forms diffract to a resolution limit of 3.0 A resolution using synchrotron radiation, and are thus suitable for X-ray structure determination.  相似文献   
20.
The development is described of a new procedure to genetically transform plant species using the male gametophyte as a natural transformation vector. Our system avoids the need for complicated regeneration procedures thus making it broadly applicable. Naked plasmid DNA encoding kanamycin resistance and GUS activity was introduced by particle gun bombardment into mature pollen grains ofNicotiana glutinosa. Bombarded pollen was used for pollinations and the resulting seeds were selected for kanamycin resistance. Two different kanamycin-resistant plants, designated VIP A and VIP B, were obtained in two independent experiments. In VIP A, TR2-driven GUS activity was observed in vascular bundles, trichomes and in a small number of pollen grains. DNA gel blot analysis indicated that the introduced DNA was integrated independently into the genome of VIP A and VIP B. It was shown that male and female gametophyte development and seed set were highly aberrant in both VIP A and VIP B and that the offspring of self- and cross-pollinations did not contain the transgenes. This might be caused by a recombination event during the integration of the naked DNA resulting in a deletion of part of the target chromosome. After meiosis such a deletion is lethal for the gametes. Our observation that the transgenes were detected in DNA isolated from sporophytic tissues but not in DNA from VIP A and VIP B pollen grains is in line with this explanation. Future experiments designed to increase the frequency of transformation and to transfer the transgenes to the offspring are discussed.  相似文献   
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