Orhan Ak - Academia.edu (original) (raw)
Papers by Orhan Ak
Journal of clinical gastroenterology, 2003
... Viral markers for hepatitis B virus and hepatitis C virus (including hepatitis C virus RNA), ... more ... Viral markers for hepatitis B virus and hepatitis C virus (including hepatitis C virus RNA), antinuclear antibody, anti-smooth muscle antibody, anti-liver-kidney microsomal antibodies type 1, antimitochondrial antibody, ATA, SLA, p-ANCA, and c-ANCA were found ... Öznur Ak, MD. ...
Cahiers de Biologie Marine
The diet of common stingray, Dasyatis pastinaca, was studied for the first time in specimens coll... more The diet of common stingray, Dasyatis pastinaca, was studied for the first time in specimens collected in the southeastern Black Sea between June 2007 and May 2008. Fish were collected in bottom trawl catch at 20-40 m depth. Overall, 8 prey taxa were identified to species level. The stomach content analysis showed that this species fed usually on crustaceans. Mud shrimp Upogebia pusilla was the most important prey. Other preys, such as anchovy Engraulis encrasicholus, red mullet Mullus barbatus ponticus and harbor crab Liocarcinus depurator were eaten occasionally whereas horse mackerel Trachurus mediterraneus, Mediterranean shore crab Carcinus mediterraneus, brown shrimp Crangon crangon and clam Venus gallina were eaten in very small amounts. The non-parametric tests with rankings were applied to feeding data to assess season, ontogenetic or sex-related changes in diet. No difference was detected between sexes and diet of small and large fish, but significant differences were found between seasons.
STECF reviewed the report of the EWG 13-12 and note d the progress made regarding the assessment ... more STECF reviewed the report of the EWG 13-12 and note d the progress made regarding the assessment of Bla ck Sea stocks. STECF acknowledges the considerable eff orts of the WG participants in undertaking its work . The EWG 13-12 attempted to develop quantitative sto ck assessments for nine species but only five of th e assessments (sprat, turbot, whiting, dogfish, and r ed mullet) are of sufficient quality to provide ana lytical estimates of recent exploitation rates and stock st atus in relation to proposed biological reference p oints. The assessment results for whiting and piked dogfish, h owever, are not sufficiently reliable to be used as a basis for short-term catch forecasts. The assessment results for horse mackerel and anchovy are less reliable a nd indicative of relative trends only. The assessment s for Atlantic bonito and rapa whelk, which were ex plorations of the available data, are inconclusive with respec t to stock status.
In this study, population features (age and sex composition, condition factor, growth and mortali... more In this study, population features (age and sex composition, condition factor, growth and mortality) and reproductive biology of golden grey mullet, Liza aurata (Risso, 1810), were determined on speciments collected from the Middle Black Sea coast (between Sinop-Samsun) between October 2001 and October 2002. The age composition varied between 1 and 6, with age group 3 dominant. The population composed
Helgoland Marine Research, 2012
Specimens of Raja clavata were monthly collected at the coast of Havaalanı (Trabzon/Turkey) from ... more Specimens of Raja clavata were monthly collected at the coast of Havaalanı (Trabzon/Turkey) from January 2009 to December 2009 at depths between 20 and 40 m. A total of 230 individuals of thornback ray (131 females and 99 males) were collected by bottom trawls during research cruises. Using logistic regression, it was determined that TL at 50% maturity of males was 718 mm TL and of females 746 mm TL. The ovarian fecundity ranged from 27 to 60 yellow follicles in both ovaries. Females carrying egg cases were found in July and October. Variations in the gonadosomatic and hepatosomatic indices indicated a continuous reproductive cycle during the year.
fbe.erciyes.edu.tr
Bu çalışmada, Karadeniz Bölgesindeki dereler üzerinde etkisi bulunan doğal ve insan kaynaklı faal... more Bu çalışmada, Karadeniz Bölgesindeki dereler üzerinde etkisi bulunan doğal ve insan kaynaklı faaliyetlerin sürdürülebilir sucul ekosistem üzerine olası etkileri incelenmiştir. Aralık 2006-Kasım 2007 döneminde aynı habitattan aylık olarak örnekleme yapılmıştır. Pilot dere olarak seçilen Yanbolu Deresinde yaşayan balık türleri tespit edilmiştir. Dere yatağını etkileyen doğal ve insan kaynaklı faktörlerin balık gruplarının biyolojik özelliklerine etkiledikleri belirlenmiştir. Anahtar Kelimeler: Yanbolu Deresi; Sucul fauna; Doğal ve insan kaynaklı faaliyetler.
Aquaculture Research, 2006
... Even after primary sex determination in fishes, sexual development contrary to the genotype c... more ... Even after primary sex determination in fishes, sexual development contrary to the genotype can be ... The result of this study showed that the lowest and the highest lethal temperature were 19 ... treatments to affect sex ratios must begin before the onset of histological gonadal sex ...
... 3.4.6. Postlarva Ergin bireyin özelliklerini göstermeye başlamış, kıskaçlar tam oluşmuş ve la... more ... 3.4.6. Postlarva Ergin bireyin özelliklerini göstermeye başlamış, kıskaçlar tam oluşmuş ve larva yerde yürümektedir. Pleopodlar tam oluşmuştur. Rostrumun üstünde ve altında dişler vardır. ... 14.Blaxter, JHS, Development: Eggs and Larvae. Fish Physiology (Edt. ...
The Turkish journal of gastroenterology: the official journal of Turkish Society of Gastroenterology
Herpes simplex hepatitis is a rare cause of acute hepatitis in immunocompetent patients. Herpes h... more Herpes simplex hepatitis is a rare cause of acute hepatitis in immunocompetent patients. Herpes hepatitis presents with nonspecific symptoms like fever, loss of appetite, vomiting, nausea and abdominal pain. Elevated transaminase values with leukopenia, relatively low bilirubin level and mucosal herpetic lesions often provide clues to the diagnosis. We describe an immunocompetent woman with herpes simplex hepatitis presenting with multiple hypodense lesions in the liver and mucocutaneous herpetic lesions.
Journal of clinical gastroenterology, 2003
... Viral markers for hepatitis B virus and hepatitis C virus (including hepatitis C virus RNA), ... more ... Viral markers for hepatitis B virus and hepatitis C virus (including hepatitis C virus RNA), antinuclear antibody, anti-smooth muscle antibody, anti-liver-kidney microsomal antibodies type 1, antimitochondrial antibody, ATA, SLA, p-ANCA, and c-ANCA were found ... Öznur Ak, MD. ...
Cahiers de Biologie Marine
The diet of common stingray, Dasyatis pastinaca, was studied for the first time in specimens coll... more The diet of common stingray, Dasyatis pastinaca, was studied for the first time in specimens collected in the southeastern Black Sea between June 2007 and May 2008. Fish were collected in bottom trawl catch at 20-40 m depth. Overall, 8 prey taxa were identified to species level. The stomach content analysis showed that this species fed usually on crustaceans. Mud shrimp Upogebia pusilla was the most important prey. Other preys, such as anchovy Engraulis encrasicholus, red mullet Mullus barbatus ponticus and harbor crab Liocarcinus depurator were eaten occasionally whereas horse mackerel Trachurus mediterraneus, Mediterranean shore crab Carcinus mediterraneus, brown shrimp Crangon crangon and clam Venus gallina were eaten in very small amounts. The non-parametric tests with rankings were applied to feeding data to assess season, ontogenetic or sex-related changes in diet. No difference was detected between sexes and diet of small and large fish, but significant differences were found between seasons.
STECF reviewed the report of the EWG 13-12 and note d the progress made regarding the assessment ... more STECF reviewed the report of the EWG 13-12 and note d the progress made regarding the assessment of Bla ck Sea stocks. STECF acknowledges the considerable eff orts of the WG participants in undertaking its work . The EWG 13-12 attempted to develop quantitative sto ck assessments for nine species but only five of th e assessments (sprat, turbot, whiting, dogfish, and r ed mullet) are of sufficient quality to provide ana lytical estimates of recent exploitation rates and stock st atus in relation to proposed biological reference p oints. The assessment results for whiting and piked dogfish, h owever, are not sufficiently reliable to be used as a basis for short-term catch forecasts. The assessment results for horse mackerel and anchovy are less reliable a nd indicative of relative trends only. The assessment s for Atlantic bonito and rapa whelk, which were ex plorations of the available data, are inconclusive with respec t to stock status.
In this study, population features (age and sex composition, condition factor, growth and mortali... more In this study, population features (age and sex composition, condition factor, growth and mortality) and reproductive biology of golden grey mullet, Liza aurata (Risso, 1810), were determined on speciments collected from the Middle Black Sea coast (between Sinop-Samsun) between October 2001 and October 2002. The age composition varied between 1 and 6, with age group 3 dominant. The population composed
Helgoland Marine Research, 2012
Specimens of Raja clavata were monthly collected at the coast of Havaalanı (Trabzon/Turkey) from ... more Specimens of Raja clavata were monthly collected at the coast of Havaalanı (Trabzon/Turkey) from January 2009 to December 2009 at depths between 20 and 40 m. A total of 230 individuals of thornback ray (131 females and 99 males) were collected by bottom trawls during research cruises. Using logistic regression, it was determined that TL at 50% maturity of males was 718 mm TL and of females 746 mm TL. The ovarian fecundity ranged from 27 to 60 yellow follicles in both ovaries. Females carrying egg cases were found in July and October. Variations in the gonadosomatic and hepatosomatic indices indicated a continuous reproductive cycle during the year.
fbe.erciyes.edu.tr
Bu çalışmada, Karadeniz Bölgesindeki dereler üzerinde etkisi bulunan doğal ve insan kaynaklı faal... more Bu çalışmada, Karadeniz Bölgesindeki dereler üzerinde etkisi bulunan doğal ve insan kaynaklı faaliyetlerin sürdürülebilir sucul ekosistem üzerine olası etkileri incelenmiştir. Aralık 2006-Kasım 2007 döneminde aynı habitattan aylık olarak örnekleme yapılmıştır. Pilot dere olarak seçilen Yanbolu Deresinde yaşayan balık türleri tespit edilmiştir. Dere yatağını etkileyen doğal ve insan kaynaklı faktörlerin balık gruplarının biyolojik özelliklerine etkiledikleri belirlenmiştir. Anahtar Kelimeler: Yanbolu Deresi; Sucul fauna; Doğal ve insan kaynaklı faaliyetler.
Aquaculture Research, 2006
... Even after primary sex determination in fishes, sexual development contrary to the genotype c... more ... Even after primary sex determination in fishes, sexual development contrary to the genotype can be ... The result of this study showed that the lowest and the highest lethal temperature were 19 ... treatments to affect sex ratios must begin before the onset of histological gonadal sex ...
... 3.4.6. Postlarva Ergin bireyin özelliklerini göstermeye başlamış, kıskaçlar tam oluşmuş ve la... more ... 3.4.6. Postlarva Ergin bireyin özelliklerini göstermeye başlamış, kıskaçlar tam oluşmuş ve larva yerde yürümektedir. Pleopodlar tam oluşmuştur. Rostrumun üstünde ve altında dişler vardır. ... 14.Blaxter, JHS, Development: Eggs and Larvae. Fish Physiology (Edt. ...
The Turkish journal of gastroenterology: the official journal of Turkish Society of Gastroenterology
Herpes simplex hepatitis is a rare cause of acute hepatitis in immunocompetent patients. Herpes h... more Herpes simplex hepatitis is a rare cause of acute hepatitis in immunocompetent patients. Herpes hepatitis presents with nonspecific symptoms like fever, loss of appetite, vomiting, nausea and abdominal pain. Elevated transaminase values with leukopenia, relatively low bilirubin level and mucosal herpetic lesions often provide clues to the diagnosis. We describe an immunocompetent woman with herpes simplex hepatitis presenting with multiple hypodense lesions in the liver and mucocutaneous herpetic lesions.