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At least 19 recordsLinked to original sources
PubMed1976

Perception as a possible source of conservation: evidence for length conservation.

In conservation problems, it is commonly assumed that equivalence judgments are not facilitated by observation of the stimuli following transformation. The reverse is usually assumed to be the case. These assumptions were tested in a training experiment. Perceptual counterparts of a series of conservation of length tests were presented to subjects who were catagorized as conservers or nonconservers on conservations of length pretests, and to conservers and nonconservers given conservation of length training. Perceptual performance of the untrained nonconservers was significantly worse than that of the other 3 groups, that is, trained nonconservers, untrained conservers, and trained conservers. These findings are interpreted as consistent with the hypothesis that conservation is attained with the support of perception, not in spite of it.

Child↗
PubMed1991

Changing indications for breast conserving therapy: proportion of patients with operable breast cancer suitable for breast conservation.

The changes in indication for breast conserving therapy and the proportion of operable stage-I and stage-II breast cancers suitable for breast conserving therapy were studied in three time periods. The percentage of patients treated with breast conserving therapy gradually increased through the years: 77/199 (39%) in 1980-1981, 122/245 (50%) in 1985-1987, and 168/305 (55%) in 1987-1989. Using the actual selection criteria more patients might have been candidates for breast conserving therapy: 69, 64 and 59 per cent respectively. In the period 1987-1989 almost all patients who were considered good candidates for breast conserving therapy had a breast sparing procedure. Indications widened in relation to age limit (less than or equal to 70 years) and, over the years, more factors became relative contra-indications: very young age, presence of extensive intra-ductal component, data from mammography (multicentricity, size and aspect of the lesion). About 40 per cent of the patients were no appropriate candidates for breast conserving therapy. This percentage would be higher when operable stage-III patients would have been included.

Age Factors↗
PubMed1977

Semi-conservative and non-conservative replication of DNA in temperature-sensitive mouse L-cells.

The mode of DNA replication has been studied in wild-type mouse L-cells (WT-4) and in two subclones (TS A1S9 and ts C1 cells) which are temperature-sensitive in DNA synthesis. It has been demonstrated that DNA is replicated by the semi-conservative mechanism in WT-4 cells grown at 34 degrees C or at 38.5 degrees C throughout the logarithmic phase and into the stationary phase. Similar results were obtained with ts A1S9 and ts C1 cells grown at the permissive temperature (34 degrees C). When the latter cells were incubated at the non-permissive temperature (38.5 degrees C) inactivation of DNA synthesis appeared to proceed through three general stages. During the first 24 h after temperature upshift suppression of semi-conservative DNA replication occurred. During the second stage a very low level of semi-conservative synthesis was maintained. During the third stage, incorporation of dThd into DNA began to increase, often reaching 10-20% of control levels after 3-5 days. During this third stage DNA synthesis was effected by a non-conservative mechanism. Temperature-inactivated ts A1S9 cells and ts C1 cells were able to perform semi-conservative synthesis upon back-shift to 34 degrees C, using as template that DNA synthesized prior to temperature upshift.

Centrifugation, Density Gradient↗
PubMed2025

Conservation genomics of a threatened subtropical Rhododendron species highlights the distinct conservation actions required in marginal and admixed populations.

With the impact of climate change and anthropogenic activities, the underlying threats facing populations with different evolutionary histories and distributions, and the associated conservation strategies necessary to ensure their survival, may vary within a species. This is particularly true for marginal populations and/or those showing admixture. Here, we re-sequence genomes of 102 individuals from 21 locations for Rhododendron vialii, a threatened species distributed in the subtropical forests of southwestern China that has suffered from habitat fragmentation due to deforestation. Population structure results revealed that R. vialii can be divided into five genetic lineages using neutral single-nucleotide polymorphisms (SNPs), whereas selected SNPs divide the species into six lineages. This is due to the Guigu (GG) population, which is identified as admixed using neutral SNPs, but is assigned to a distinct genetic cluster using non-neutral loci. R. vialii has experienced multiple genetic bottlenecks, and different demographic histories have been suggested among populations. Ecological niche modeling combined with genomic offset analysis suggests that the marginal population (Northeast, NE) harboring the highest genetic diversity is likely to have the highest risk of maladaptation in the future. The marginal population therefore needs urgent ex situ conservation in areas where the influence of future climate change is predicted to be well buffered. Alternatively, the GG population may have the potential for local adaptation, and will need in situ conservation. The Puer population, which carries the heaviest genetic load, needs genetic rescue. Our findings highlight how population genomics, genomic offset analysis, and ecological niche modeling can be integrated to inform targeted conservation.

Rhododendron↗
PubMed1992

Nucleotide sequence of the capsid protein gene of two serotypes of San Miguel sea lion virus: identification of conserved and non-conserved amino acid sequences among calicivirus capsid proteins.

The San Miguel sea lion viruses, members of the calicivirus family, are closely related to the vesicular disease of swine viruses which can cause severe disease in swine. In order to begin the molecular characterization of these viruses, the nucleotide sequence of the capsid protein gene of two San Miguel sea lion viruses (SMSV), serotypes 1 and 4, was determined. The coding sequences for the capsid precursor protein were located within the 3' terminal 2620 bases of the genomic RNAs of both viruses. The encoded capsid precursor proteins were 79,500 and 77,634 Da for SMSV 1 and SMSV 4, respectively. The SMSV 1 protein was 47.7% and SMSV 4 was 48.6% homologous to the feline calicivirus (FCV) capsid precursor protein while the two SMSV capsid precursors were 73% homologous to each other. Six distinct regions within the capsid precursors (denoted as regions A-F) were identified based on amino acid sequence alignment analysis of the two SMSV serotypes with FCV and the rabbit hemorrhagic disease virus (RHDV) capsid protein. Three regions showed similarity among all four viruses (regions B, D and F) and one region showed a very high degree of homology between the SMSV serotypes but only limited similarity with FCV (region A). RHDV contained only a truncated region A. A fifth region, consisting of approximately 100 residues, was not conserved among any of the viruses (region E) and, in SMSV, may contain the serotype-specific determinants. Another small region (region C) contained between 15 and 27 amino acids and showed little sequence conservation. Region B showed the highest degree of conservation among the four viruses and contained the residues which had homology to the picornavirus VP3 structural protein. An open reading frame, found in the 3' terminal 514 bases of the SMSV genomes, encoded small proteins (12,575 and 12,522 Da, respectively for SMSV 1 and SMSV 4) of which 32% of the conserved amino acids were basic residues, implying a possible nucleic acid-binding function.

Amino Acid Sequence↗
PubMed1992

[Conservative treatment for trauma of the spleen in adults. Comparative study of thirty-four cases of conservative treatment and sixty-one cases of splenectomy].

Between 1983 and 1990, 95 patients with abdominal injury and splenic damage underwent surgery. Conservative treatment was performed in 34 cases (group I) and splenectomy was performed in 61 cases (group II). In group I, one patient died and post-operative complications occurred in 18 patients (53%). In group II, 3 patients died (of a 0hrenic abscess for one of them), and postoperative complications occurred in 38 patients (62%). There was no significant difference between group I and group II in terms of length of hospital stay and operation time; but a greater number of red cell concentrates was required during the operation in group II. No patient of group I developed post-operative infection during the mean interval of 18 months. This experience confirms that the conservative treatment of splenic contusions does not worsen the prognosis of abdominal injuries. Medium and long term infectious complications might be prevented by the conservative treatment but it is still too early to assess the real benefit of this option.

Abdominal Injuries↗
PubMed1991

Mapping of the gene for a major penicillin-binding protein to a genetically conserved region of the Bacillus subtilis chromosome and conservation of the protein among related species of Bacillus.

Penicillin-binding protein 5 is the most abundant penicillin-binding protein in the vegetative membranes of Bacillus subtilis and accounts for 95% of the D,D-carboxypeptidase activity of the cell. The structural gene for penicillin-binding protein 5 was mapped to a genetically conserved region near guaB at 0 degrees on the B. subtilis chromosome, and immunoassays revealed that there is conservation of this major penicillin-binding protein among related species.

Bacillus↗
PubMed1992

Factors influencing local relapse and survival and results of salvage treatment after breast-conserving therapy in operable breast cancer: EORTC trial 10801, breast conservation compared with mastectomy in TNM stage I and II breast cancer.

A (modified) radical mastectomy (RM) was compared with breast-conserving therapy (BCT) in stage I and stage II breast cancer patients. Treatment of the study arm comprised lumpectomy, axillary clearance and radiotherapy to the breast (50 Gy in 5 weeks external irradiation and a boost with iridium implant of 25 Gy). 902 patients were included. There were 734 TNM stage II patients. Patients with microscopically incomplete excision of the tumour were not excluded. After a median follow-up of 6 years, overall survival and local recurrence rates do not differ significantly between the two study arms. Actuarial survival at 8 years was 73% after RM and 71% after BCT; actuarial local recurrence at 8 years was 9% and 15%, respectively. In the mastectomy group tumour size did not affect local relapse, but after BCT the incidence of local recurrences was higher for tumours of 2-5 cm (16%) than for smaller tumours (7%) (at 8 years, P = 0.08). Results of salvage treatment for local recurrence so far were similar in both the BCT and the mastectomy group.

Aging↗
PubMed1979

Conservative treatment with total parenteral nutrition in patients with gastroesophageal anastomotic leaks (anastomotic leaks conservatively treated).

Seventeen patients with anastomotic leaks after operation for cardiac or upper gastric cancers were treated conservatively with parenteral nutrition, antibiotics and drainage. Ten patients healed after in mean 33 days, while seven died. All febrile patients had elevation of blood urea, and four had abnormal hepatic enzymes during the parenteral nutrition. There were no significant venous or infectious complications due to the parenteral nutrition.

Anti-Bacterial Agents↗
PubMedDate not supplied

Conservative total hip arthroplasty: a procedure to conserve bone stock. Part I: analysis of sixty-six patients. Part II: analysis of failures.

Pain relief, function, and range of motion in surface replacement hip arthroplasty is comparable to the Charnley-type conventional arthroplasty. Patients with primary and secondary degenerative hip disease are the most suitable candidates for surface replacement. Previous operations, especially mold arthroplasty, increases incidence of failure. Osteopenia, obesity, or congenital deficiency of the acetabulum also increases the incidence of failure. Intraoperative preservation of abductor continuity and rigorous postoperative abductor strengthening are necessary to insure the success of the procedure. A minimum of 18 months is necessary to adequately evaluate the procedure. Acetabular loosening is avoidable. Hemispherical reaming of the femoral head did not contribute to femoral component loosening. Traumatic femoral neck fracture is a concern, but atraumatic femoral neck fracture can be avoided through improved operative technique, and by a program of rehabilitation of hip musculature. The procedure is indicated in the relatively young, well-motivated, non-obese patient with degenerative joint disease who has normal hip musculature.

Acetabulum↗
PubMed1991

Adhesive small bowel obstruction in children: the place and predictors of success for conservative treatment.

The records of 230 adhesive small bowel obstruction (ASBO) episodes in 181 patients have been reviewed to observe the place of conservative treatment and to establish criteria to predict the success of conservative trial. Immediate operation has been reserved for 81 episodes that have presented with fever and leucocytosis and/or localized abdominal tenderness, or complete obstruction. The remaining 149 episodes have initially undergone conservative trial. Although 110 episodes (73.8%) have been cured with conservative trial, 39 (26.2%) subsequently necessitated surgical intervention. No adverse occurrences have been observed during or after delayed operations. There was no strangulated bowel nor mortality both in delayed operation and conservatively treated groups. Recurrence has occurred with rate of 18.75% and 36.47% after surgery and conservative treatment, respectively, being significantly different (P less than .01), but the treatment method of the previous episode has been without influence on the method used in the recurrent obstruction (P less than .05). Among the assumed predictive criteria, age at recent laparotomy (P less than .02), time elapsed between recent laparotomy and obstructive episode (P less than .01), the primary condition necessitating laparotomy (P less than .01), the incision of previous laparotomy (P less than .05), and duration of conservative trial (P less than .01) correlated significantly with the success of conservative trial. The number of previous laparotomies and obstructive episodes (P less than .05) have not showed correlation. By the conservative approach used in selected patients with ASBO, 40% overall have been spared operation, without any adverse occurrences. Using the proposed criteria, the success rate of conservative treatment can be predicted.

Adolescent↗
PubMed2026

Beauty bias in butterfly research and conservation.

Conservation biases have been documented since the first emergence of the concept of biodiversity in the 1980s,1,2,3 showing a systematic disproportion in the allocation of research and conservation efforts among taxa.4,5,6,7,8,9,10,11 One factor underlying this disproportion, gaining prominence in recent literature, is species' perceived beauty, shaped by human visual preferences.12,13,14,15,16,17 Here, we integrate a large-scale survey of the perceived beauty of European butterflies yielding >21,000 survey completions from >100 countries into a time-explicit network linking species' beauty, public attention, research and conservation efforts, and the EU regulatory framework. We found that species beauty is consistently associated with public attention, research, and conservation efforts in a temporally structured pattern compatible with a cumulative beauty bias. Research effort and public attention concentrate on widespread and visually attractive species, whereas species included in the legal conservation framework, particularly the Convention on the Conservation of European Wildlife and Natural Habitats (hereafter, Bern Convention, BC, 1979)18 and the EU Habitats Directive (hereafter, HD, 1992)19 are disproportionately represented by visually appealing and historically protected taxa. Because these frameworks guide funding and management actions, early associations between species beauty and BC/HD inclusion have contributed to long-lasting institutional patterns in butterfly research and conservation. By contrast, European IUCN Red Lists20,21 do not overrepresent beautiful species and identify more inconspicuous taxa as threatened. This mismatch reveals a tension between scientific assessments of extinction risk and historically embedded conservation priorities. Our findings suggest that recognizing beauty bias is vital for aligning conservation with actual ecological urgency. VIDEO ABSTRACT.

Animals↗