bluuebunny/crossref_metadata_2025_split huggingface dataset:
Postmenopozal Kadınlarda Kemik Mineral Dansitometri Değerleri ile Hematolojik Parametrelerin Karşılaştırılması
Authors: GÜZEL Yunus 
Published: May 2021

Öz
Amaç: Postmenopozal kadınlarda hemogram değerleri, nötrofil lenfosit oranı, trombosit lenfosit oranı ve kemik mineral dansitometri değerleri arasındaki ilişkiyi değerlendirerek hangi parametrenin kemik mineral dansitometri değerleri ile daha güçlü bir ilişki içinde olduğunu belirlemeyi amaçladık.
Yöntemler: Bu çalışmada vücut kitle indeksi 25-30 arasında değişen, 50-60 yaş arası 64 postmenopozal kadın hastanın kemik mineral dansitometri değerleri, nötrofil lenfosit oranı, trombosit lenfosit oranı ve hemogram parametreleri (beyaz kan hücresi, kırmızı kan hücresi, hemoglobin, platelet, lenfosit, monosit, basofil, nötrofil, eosinofil) geriye dönük olarak incelendi. Kemik mineral yoğunluğunu veya hemogram değerlerini etkileyebilecek klinik durumlar (akut ve kronik enfeksiyonlar, onkolojik, romatolojik ve hematolojik hastalıklar, kronik karaciğer ve böbrek hastalıkları, hiperparatiroidi, hipotiroidi, hipertiroidi, D vitamini eksikliği, steroid kullanımı ve son 1 yıl içerisinde geçirilmiş travma veya kan transfüzyonu öyküsü) çalışma dışı bırakıldı. Daha sonra kemik mineral dansitometri değerleri ile hematolojik parametreler arasında korelasyon analizi yapıldı.
Bulgular: Çalışmamızda platelet lenfosit oranı ile femur boynu kemik mineral dansitesi, femur boynu Z skoru ve femur boynu T skoru arasında istatistiksel olarak anlamlı negatif korelasyon saptandı (p=0.004, r=-0.353; p=0.005, r=-0.344; p=0.004, r=-0.359, respectively). Ayrıca monosit değerleri ile femur boynu kemik mineral dansitesi, femur boynu Z skoru ve femur boynu T skoru arasında istatistiksel olarak anlamlı pozitif korelasyon saptandı (p=0.030, r=0.272; p=0.038, r=0.259; p=0.022, r=0.285, respectively). Nötrofil lenfosit oranı ile kemik mineral dansitometri parametreleri arasında ilişki saptanmadı.
Sonuç: Yüksek platelet lenfosit oranı ve düşük monosit değeri, menopoz sonrası kemik dansite oranlarındaki değişimleri tahmin etmeye yardımcı olmak için kullanılabilecek basit belirteçler olabilir.
Küçük ve Dev Ensefalosellerin Etiyolojik Faktörler ve Peroperatif Süreç Açısından Karşılaştırılması
Authors: AYDIN ÖZTÜRK Pınar 
Published: May 2021

Amaç: Ensefaloseller konjenital nöral tüp defeklerinden olup beyin ve/veya meninkslerin kafatasındaki bir defektten dışarı çıkması ile karakterizedir. Ensefalosel kesesinin kafadan büyük olduğu olgular ‘dev ensefaloseller’ olarak adlandırılırlar. ‘Dev ensefalosel’lerin yönetimi küçük keseli ensefalosellerden oldukça farklıdır. Bu çalışma ile küçük ve dev ensefaloseller karşılaştırılarak etiyolojik ve peroperatif yönetim açısından karşılaştırılmıştır.
Yöntemler: Hastanemizde yenidoğan döneminde opere edilen ensefaloseller boyutlarına göre iki gruba ayrılarak ayrı ayrı ve karşılaştırılmalı olarak değerlendirilmiştir.
Bulgular: Çalışmaya ensefalosel nedeniyle opere edilen 32 hasta dahil edilmiştir. Hastaların %62,5’i kız bebek, %37,5’i erkek bebektir. Hastaların %15,6’sında ‘dev ensefalosel’ mevcuttu. Hastaların %53,1’inde kese içerisine herniye olmuş nöral doku mevcuttu. Hastaların %21,9’unda ek anomali mevcuttu. Hastaların %65,6’sında doğumda veya bir yıllık takip süresinde şant takılmasını gerektirecek ventriküler dilatasyon saptanmıştır. Kese boyut ortalaması 74.6±110.3 cm² olarak saptanmıştır. Kese boyutu arttıkça defisit gelişme riski daha yüksek bulunmuştur (p = 0.023).
Sonuç: Ensefaloseller peroperatif süreci multidisipliner bir anlayışla iyi yönetilmesi gereken bir hasta grubudur. Her ne kadar ‘dev ensefaloseller’in postoperatif süreci diğer ensefalosellerle aynı olsa da preoperatif hazırlığın dikkatli yapılması, anestezi ve cerrahi ekibin koordine çalışması diğer ensefalosellere göre yüksek olan peroperatif komplikasyon riskini azaltacaktır.
Kanser Tanısı Almış Hastalarda Kemik Metastazlarının Belirlenmesinde Kemik Sintigrafisi ile Kemik Spesifik Alkalen Fosfataz ve Total Alkalen Fosfataz Düzeylerinin Karşılaştırılması
Authors: ALTINDAĞ Serdar 
Published: May 2021

Giriş: Hayatı tehdit eden bir sağlık sorunu olan kanserlerin takibinde metastazların erken tespiti önemlidir. Kanserlerin kemik metastazlarının belirlenmesinde kemik sintigrafisi önemli bilgiler veren ve öncelikle tercih edilen bir yöntemdir. Bu çalışmamızda kemik sintigrafisiyle iskelet sisteminde metastaz saptanan hastalarda, kemik spesifik alkalen fosfataz (bALP) ve total alkalen fosfataz (tALP) değerlerinin kemik sintigrafisi bulguları ile uyumunu göstermeyi amaçladık.
Yöntemler: Patolojik olarak kanser tanısı almış 92 hastaya rutin Tc-99m HDP ile kemik sintigrafisi çekildi. Hastaların bALP ve tALP değerleri çalışıldı. Sayısal verilerin istatistiksel analizleri için SPSS (Statistical Package for Social Sciences) for Windows 15.0 paket programı kullanıldı.
Bulgular: Doksan iki hastanın 54’ünde kemik sintigrafisinde kemik metastazı tespit ettik, 92 hastanın 38’inde ise metastaz tespit etmedik. Sintigrafik olarak kemik metastazı saptadığımız hasta grubu ile kemik metastazı saptamadığımız hasta grubu arasında bALP ve tALP değerleri açısından anlamlı fark bulduk (p
COVID-19’lu Hastalarda Tedaviye Bağlı Karaciğer Hasarı Gelişme Sıklığı, Favipravir bu Tabloda ne Kadar Etkili?
Authors: EBİK Berat 
Published: May 2021

Amaç: Çalışma amacımız; COVID-19 tedavisinde kullanılan ilaçların karaciğer fonksiyon testleri üzerindeki etkisini incelemek ve hastalarda tedavi sırasında ilaca bağlı karaciğer hasarı (İBKH) gelişim sıklığını araştırmaktır. Ayrıca literatürde karaciğer üzerindeki etkisiyle ilgili çok fazla veri olmayan favipravirin; COVID-19 tedavisinde yaygın bir şekilde kullanılmaya başlanmasıyla gelişen karaciğer fonksiyon bozukluklarının favipravir ile ilişkisini araştırmaktır.
Yöntemler: Çalışmamıza 2020 Nisan-Eylül döneminde PZR (polimeraz zincir reaksiyonu) testi ile COVID 19 tanısı konulan ve hastanede yatarak tedavi gören 1301 hasta aldık. Önceden bilinen kronik karaciğer hastalığı olanları, COVID-19 sırasında sitokin fırtınası, sepsis ve iskemik hepatit gelişen hastaları çalışmaya almadık. Hastaları kullandıkları ilaç tedavisine göre gruplara ayırdık. Gruplar arasında, karaciğer fonksiyon bozukluğu ve İBKH gelişen vaka sayısında fark olup olmadığını inceledik.
Bulgular: Çalışmaya aldığımız 1301 hastanın %50.2 sinde tedavi sırasında ALT-AST yüksekliği gelişmesine rağmen bu yüksekliklerin %45.3’ünün hafif ve orta düzeyde enzim artışı olduğu görüldü. Hastaların %4,9’unda İBKH gelişti. Sadece favipravir alan hastaların %1,1’inde İBKH gelişmesine karşın; favipravir+antibiyotik alan hastalarda bu oran %8,7 idi.(p
Deneysel Diyabetik Sıçan Modelinde Zamana Bağlı Gelişen Kemik Dokusundaki Değişikliklerin İncelenmesi
Authors: KEŞİM Dilek Aygün 
Published: May 2021

Amaç: Streptozotocin (STZ) ile oluşturulan diyabetin, kemik metabolizması üzerine etkisinin araştırılması amaçlanmıştır.
Yöntemler: Çalışmada 28 adet 350-400 gr ağırlığında Wistar albino türü erkek sıçanlar kullanıldı. Her bir grupta 7 adet sıçan kullanıldı. Sıçanlar 2 haftalık kontrol ve diyabet (streptozotocin), 8 haftalık kontrol ve diyabet olmak üzere toplam 4 gruba ayrıldı. Diyabetli gruplara tek seferlik streptozotocin 45 mg/kg doz karın boşluğuna enjekte edildi. Sıçanlar belirlenen haftalarda ketamin anestezisi altında kardiyak ponksiyonla feda edilerek, kan ve sağ tibia örnekleri alındı. Tibiaları hemotoksilen boya ile boyanıp, histopatolojik görüntüleri elde edildi. Tibia uzunlukları ölçülüp kaydedildi. Kan serum örneklerinden vitamin D, kalsiyum, magnezyum, fosfat ve alkalen fosfataz değerleri ölçüldü.
Bulgular: Hem iki hem de sekiz haftalık diyabetik grupların kendi kontrollerine kıyasla vücut ağırlığında anlamlı azalma göründü (p
Lumbal Disk Hernili Hastalarda Hastalık Evresi Postüral Kontrolü Etkiler Mi?
Authors: SOYSAL TOMRUK Melda 
Published: May 2021

Amaç: Lumbal disk hernisi (LDH) genellikle L5-S1 düzeyinde meydana gelen, ağrı ve somatosensöriyel kayıplara neden olan bir durumdur. Bu nedenle hastalarda postüral kontrolde azalmalar meydana gelir. Çalışmanın amacı LDH hastalarında hastalık evresinin postüral kontrole etkisini araştırmaktı.
Yöntemler: Çalışma kesitsel bir araştırmadır. Çalışmaya bulging evresinde 22, protrüzyon evresinde ise 33 hasta olmak üzere L5-S1 seviyesinde LDH olan 55 hasta dahil edildi. Hastaların ağrı, özürlülük ve postüral kontrolleri sırasıyla; Görsel Ağrı Skala (GAS), Oswestry Özürlülük İndeksi ve Biodex denge cihazı ile ölçüldü. Postüral kontrol değerlendirmesi için kararlılık sınırları (KS) ve duyusal etkileşim denge testi (DEDT) kullanıldı. Gruplar arası farklar, Student’s t test testi ile belirlendi.
Bulgular: Gruplar arasında yaş, hastalık süresi, ağrı ve özürlülük düzeyi açısından anlamlı fark yoktu (p>0.05). Bulgingi olan grubun sol yön KS test skoru protrüzyon evresinde olan hastalardan anlamlı ölçüde düşüktü (p
Resveratrol improves cardiac function and left ventricular fibrosis after myocardial infarction in rats by inhibiting NLRP3 inflammasome activity and the TGF-β1/SMAD2 signaling pathway
Authors: Jiang Jinjin , Gu Xiuping , Wang Huifeng , Ding Shibin 
Published: May 2021

Background
Several studies have shown that resveratrol (RES), a naturally occurring polyphenol found in many plants, is beneficial for preventing cardiovascular diseases. However, the mechanism underlying the RES-mediated protection against myocardial infarction has not yet been revealed entirely. In this study, we investigated the protective effects of RES on cardiac function in a rat model of acute myocardial infarction (AMI) and the related underlying mechanisms.

Methods
Male Sprague-Dawley rats were randomly divided into four groups: Sham (sham operation), Sham-RES, AMI (AMI induction), and AMI-RES. The rat AMI model was established by the permanent ligation of left anterior descending coronary artery method. The rats in the RES-treated groups were gavaged with RES (50 mg/kg/day) daily for 45 days after the Sham operation or AMI induction; rats in the Sham and AMI groups were gavaged with deionized water. Cardiac function was evaluated by echocardiography. Atrial interstitial fibrosis was assessed by hematoxylin-eosin or Masson’s trichrome staining. Real-time PCR and western blotting analyses were performed to examine the levels of signaling pathway components.

Results
RES supplementation decreased the inflammatory cytokine levels, improved the cardiac function, and ameliorated atrial interstitial fibrosis in the rats with AMI. Furthermore, RES supplementation inhibited NLRP3 inflammasome activity, decreased the TGF-β1 production, and downregulated the p-SMAD2/SMAD2 expression in the heart.

Conclusion
RES shows notable cardioprotective effects in a rat model of AMI; the possible mechanisms underlying these effects may involve the improvement of cardiac function and atrial interstitial fibrosis via the RES-mediated suppression of NLRP3 inflammasome activity and inhibition of the TGF-β1/SMAD2 signaling pathway in the heart.
Establishment of a modified percutaneous CT-guided paraspinal intramuscular VX-2 squamous cell carcinoma dual tumor model in rabbits
Authors: Meng Liangliang , Shan Husheng , He Xiaofeng , Zhou Jiantao , Huang Jingxiang , Zhang Xin , Ma Li , Xue Xiaodong , Zhang Zhongliang , Xiao Yueyong 
Published: May 2021

Background
The rabbit VX-2 tumor model is a commonly used transplanted tumor model and is widely used in surgical, radiological, and interventional studies. Most of the known tumor models for each site are single solid tumors. This study aimed to establish an accurate and stable intramuscular dual tumor model guided by computed tomography (CT).

Methods
In this study, we compared three different inoculation methods to select the most appropriate dual tumor model. Six New Zealand White rabbits were used as tumor-carrying rabbits for tumor harvesting. Thirty rabbits were divided into three groups as experimental rabbits. Group A applied the tumor cell suspension method, in which the suspension was injected into the designated location with a syringe under CT guidance. Groups B and C used tumor tissue strips obtained in vivo or under direct in vitro vision. The tumor tissue strips were implanted into the designated locations using a guide needle under CT guidance. The differences in tumorigenic rate, the size difference between bilateral tumors, and metastasis between the three methods were compared.

Results
It was found that group A obtained a 100% tumor survival rate, but the size of the tumor was more variable, and needle tract implantation metastasis occurred in 5 cases. In group B, tumor tissue strips were taken in vivo for implantation, in which one case failed to survive. Tumor tissue strips in group C were obtained in vitro under direct vision. The tumor tissue strips obtained in vitro by puncture using a biopsy needle in group C had a 100% tumorigenicity rate and stable tumor size. No significant needle tract implantation metastases were found in either group B or C. The variance of tumor size obtained in group A was significantly higher than in groups B and C. The variance of tumor size in group C was the smallest. Group C had high tumorigenicity and a more stable size and morphology of the formed tumors.

Conclusion
The results showed that the method of obtaining tumor tissue strips using in vitro direct vision puncture and implanting them into the muscle with CT guidance and guide needles can establish an accurate and stable dual tumor model. This dual tumor model can provide substantial support for relevant preclinical studies.
Passive Propagation of Electrical Signals
Authors: Elmslie Keith S 
Published: May 2021

Abstract

Electrical potentials can be propagated along biological membranes in either an active or passive manner. Passively propagated potentials include synaptic and receptor potentials, which are potentials that can be summed in a time and spatially dependent manner to alter their amplitude. The time course, speed and distance travelled of passively propagated potentials depend on three properties: membrane resistance, membrane capacitance and axial resistance. Of these properties, membrane resistance and axial resistance can vary among neurons to affect conduction of electrical signals. Any change in axonal properties that increase the distance travelled by passively propagated electrical signals will increase the speed by which the action potential travels along the axon (i.e. conduction velocity). To increase conduction velocity, vertebrate axons can be wrapped with myelin to increase the membrane resistance and decrease membrane capacitance, and they can have increased axonal diameter to decrease axial resistance. The passive electrical properties have wide ranging effects on neuronal electrical signalling.

Key Concepts

Electrical signals can be propagated along membranes by passive and active processes.

The neuronal properties that govern passive propagation impact the integration of synaptic signals and the speed of action potential propagation.

These properties are the membrane resistance (
R
M
), membrane capacitance (
C
M
) and resistance of the cytoplasm (also called axoplasm when in the axon).

R
M
and
C
M
combine to determine the change in membrane voltage with time in response to an injection of current (e.g. synaptic current due to activation of postsynaptic neurotransmitter receptors).

These properties, including the resistance of the axoplasm (also called axial resistance,
R
A
) determine the passive change in membrane voltage with distance from the current injection.

Myelination increases axonal
R
M
and decreases axonal
C
M
, both of which increase the speed by which action potentials are propagated along the axon (axonal conduction velocity).

R
A
is decreased in axons with larger diameters, and the axonal conduction velocity increases with decreased
R
A
.

Demyelination of axons by diseases such as multiple sclerosis disrupts action potential propagation along axons by decreasing
R
M
, which shortens the distance by which electrical signals are propagated. This results in action potential propagation failure, which leads to the functional deficits associated with this disease.
Protozoa
Authors: Pánek Tomáš 
Published: May 2021

AbstractProtozoa may be considered as (mostly) microscopic, essentially single‐celled, eukaryotes that ingest other organisms or their products (i.e. as heterotrophic protists). Protozoa are no longer recognised as a taxonomic group because they do not constitute a monophylum and can be found in all main eukaryotic lineages, informally called supergroups. They play important roles in the ecology of aquatic habitats and soils, for example, by controlling bacterial populations and releasing nutrients for use by other organisms. As parasites, protozoa have very profound effects on humans, both directly and through their effects on domesticated animals. Some protozoa have shells or skeletal structures that can fossilise and certain groups, particularly the foraminifera, are used in biostratigraphy and in locating oil deposits.Key ConceptsProtozoa are single‐celled eukaryotes (protists) that obtain their food by eating other organisms or their products.Protozoa are not a taxonomic group but rather a diverse assemblage of heterotrophic, distantly related lineages, with representatives in all eukaryote supergroups.Protozoa help to understand evolution of multicellularity since animals and fungi evolved from them.Study of protozoa provides an inside into the biology of the last eukaryotic common ancestor and the evolution of eukaryotic cell.Algae (photosynthetic protists) evolved from protozoa several times independently by acquiring plastid from cyanobacteria (primary plastid) or other plastid‐bearing protists (secondary and tertiary plastids).Protozoa diversified to a tremendous number of morphological forms; two elementary body plans are flagellate and amoeba. The amoeboid body plan was invented several times during the evolution of eukaryotes.Protozoa are found in almost every habitat where there is a sufficient amount of water and may survive adverse environmental conditions by the production of cysts or spores.Protozoa play key roles in nutrient cycling and soil fertility and are the main predators of bacteria in many environments.A wide range of human and animal diseases are caused by protozoa.Fossil protozoa are used to help locate oil deposits and to reconstruct past climate changes.
Reproduction in Monotremes and Marsupials
Authors: Renfree Marilyn , Shaw Geoffrey 
Published: May 2021

Abstract

The three subclasses of mammals – the monotremes, the marsupials and the eutherians – are most clearly distinguished from one another by their mode of reproduction and the anatomy of their reproductive tracts. The monotremes are all oviparous, delivering an egg from which hatches an immature young that depends on milk. The echidna has a transient pouch. Similarly, the living species of marsupials all give birth to small, altricial young that in most species are retained in the mother's pouch during the extended lactational period. Marsupials can also have a period of embryonic diapause in which development of the early embryo in the uterus ceases until it receives a signal to reactivate such as a seasonal or lactational one. New molecular studies and genome analyses are highlighting similarities and differences in these mammals that inform us about their evolution.

Key Concepts

Monotremes and marsupials are mammals having fur and can lactate.

Reproductive anatomy differs between all three mammalian groups.

Monotremes are the only egg‐laying mammals and also have a short‐lived yolk sac placenta.

Pregnancy is short in marsupials and always less than one month.

Marsupials have a fully functional yolk sac placenta.

Lactation is relatively long, and the milk changes its composition throughout the growth and development of the young.

Sexual differentiation occurs after birth in marsupials.

Marsupial and monotreme genomics is advancing our understanding of mammalian evolution.
Arboreal Locomotion: Moving in the Trees
Authors: Polet Delyle T , Bertram John EA 
Published: May 2021

Abstract

Diverse groups of animals have adapted to exploiting the unique environment of the forest canopy. The arboreal environment is complex and these animals encounter many unique physical challenges as they move up to and through tree branches. Solving these challenges involves dealing with the physical implications of moving on surfaces of various sizes and surface textures. Understanding how these organisms contend with the environment depends on understanding the fundamental factors involved in moving vertically and horizontally while maintaining stability. In most cases, highly specialised anatomy is required to support adhesion, claw penetration and friction contact through gripping, either with digits, a prehensile tail or the body wall. Body size provides hard limits on the ability to exploit the arboreal environment. In the remarkably agile brachiating apes, their specialised locomotion involves subtle dynamics to exploit the energy‐saving benefits of swinging below their supports – an advantage not available in overground locomotion.

Key Concepts

To climb, an animal must resist gravity, whether horizontal or vertical to the surface.

On a vertical trunk, limbed animals must resist a weight‐induced tipping moment.

On a horizontal branch, an animal must stabilise itself to avoid falling, unless it hangs from the branch.

Small animals have more supports available to them in climbing and are relatively strong compared to their weight.

Animals have evolved various specialisations to attach to surfaces, whether through sticking, clinging or gripping.

Brachiation is an economical and adaptable locomotor mode unique to the arboreal environment.
Hybrid Zones
Authors: Stankowski Sean , Shipilina Daria , Westram Anja M 
Published: May 2021

AbstractHybrid zones are narrow geographic regions where different populations, races or interbreeding species meet and mate, producing mixed ‘hybrid’ offspring. They are relatively common and can be found in a diverse range of organisms and environments. The study of hybrid zones has played an important role in our understanding of the origin of species, with hybrid zones having been described as ‘natural laboratories’. This is because they allow us to study,in situ, the conditions and evolutionary forces that enable divergent taxa to remain distinct despite some ongoing gene exchange between them.Key ConceptsHybrid zones are narrow geographic regions where different populations, races or interbreeding species meet and mate, producing mixed ‘hybrid’ offspring.They are relevant to understanding local adaptation and speciation as they show us how taxa can remain distinct despite gene flow.Hybrid zones can occur at environmental boundaries between taxa adapted to different habitats or separate taxa with genetic incompatibilities.Many hybrid zones are maintained by a balance between selection and gene flow, creating sharp spatial gradients (clines) in traits and allele frequencies.Extensive theory has been developed that quantitatively relates cline shapes to evolutionary processes in hybrid zones.The strength of selection can vary across the genome and phenome, which causes some loci or phenotypes to show sharper clines than others.Hybrid zones can form in a continuous population (primary origin) or when two populations diverge in isolation and come into secondary contact (secondary origin).The long‐term outcomes of hybridisation can vary: Hybrid zones can collapse, move in space or be maintained as stable phenomena.An array of methods can be applied to empirical data collected from hybrid zones, in particular to identify loci under selection.Emerging methods will ensure that hybrid zones will continue to advance our understanding of speciation in the future.