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1.
Surg Today ; 43(5): 547-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22766896

RESUMO

Fetus in fetu (FIF) is a rare condition in which a malformed fetus resides in the body of its host. The presence of a well-formed vertebral column secures the diagnosis of FIF and differentiates this entity from a teratoma. Although more than 100 cases of FIF have been reported in the literature, the presence of a well-formed vertebral column is not documented in many cases. We herein report the case of a 19-day-old female who presented with a lump in the abdomen. Plain radiograph of the abdomen showed the presence of a well-formed vertebral column with long bones, and the results were confirmed with ultrasonogram and CT scans. Therefore, a preoperative diagnosis of FIF was made, and the mass was successfully excised. Upon opening the sac of the mass, a malformed anencephalic fetus was found.


Assuntos
Abdome/anormalidades , Abdome/cirurgia , Anormalidades Congênitas/cirurgia , Feto/anormalidades , Feto/cirurgia , Testes de Impedância Acústica , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/patologia , Diagnóstico Diferencial , Diagnóstico por Imagem , Feminino , Feto/patologia , Humanos , Recém-Nascido , Laparotomia , Gêmeos
2.
Case Rep Anesthesiol ; 2020: 3714718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082636

RESUMO

A 4-year-old child had closure of tracheocutaneous fistula under general anaesthesia. He developed extensive surgical emphysema over the face, chest, and upper abdomen immediately in the recovery room. We gave him oxygen supplementation, removed surgical stitch, and inserted a 4 mm tracheostomy tube to secure airway. Chest X-ray ruled out pneumothorax or pneumomediastinum. After a week, a tight bandage was applied which approximated the tissue and helped in the closure of stoma; no suture was applied. The patient was discharged home on the fourth postoperative day. The patient needs close observation in the postoperative period with likely complication in mind. Recognizing early signs and symptoms of respiratory distress with quick intervention is lifesaving during the complication of tracheocutaneous fistula surgery. In absence of pneumothorax or pneumomediastinum, extensive surgical emphysema occurring during primary closure of tracheocutaneous fistula can be treated without inserting any drainage tube.

3.
J Inequal Appl ; 2018(1): 65, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29606842

RESUMO

The notion of statistical weighted [Formula: see text]-summability was introduced very recently (Kadak et al. in Appl. Math. Comput. 302:80-96, 2017). In the paper, we study the concept of statistical deferred weighted [Formula: see text]-summability and deferred weighted [Formula: see text]-statistical convergence and then establish an inclusion relation between them. In particular, based on our proposed methods, we establish a new Korovkin-type approximation theorem for the functions of two variables defined on a Banach space [Formula: see text] and then present an illustrative example to show that our result is a non-trivial extension of some traditional and statistical versions of Korovkin-type approximation theorems which were demonstrated in the earlier works. Furthermore, we establish another result for the rate of deferred weighted [Formula: see text]-statistical convergence for the same set of functions via modulus of continuity. Finally, we consider a number of interesting special cases and illustrative examples in support of our findings of this paper.

4.
J Environ Pathol Toxicol Oncol ; 12(4): 219-27, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8189379

RESUMO

Damaging effects of diazinon, an organophosphorus insecticide, on the gills of bluegills, Lepomis macrochirus, are many. Adult bluegills were exposed to 15, 30, 45, 60, and 75 micrograms/L of diazinon and their gills were microscopically examined. Compared to the gill structure of the control fish, all the diazinon concentrations caused various types of changes, such as lifting of the epithelial layer, hyperplasia and necrosis, shortening of the lamellae and frequent epithelial rupture, lamellar fusion, severe hyperplasia and mucous cells hypertrophy, extensive fusion, and clavate lamellae. Some of the structural changes may serve as a defense mechanism in protecting the fish from the diazinon-contaminated water by increasing the diffusion distance. Increase in the diffusion distance and mucus secretion can adversely affect the respiration of the fish, ultimately leading to its death.


Assuntos
Diazinon/toxicidade , Brânquias/efeitos dos fármacos , Perciformes , Animais , Brânquias/patologia , Hiperplasia/induzido quimicamente , Necrose
5.
J Environ Pathol Toxicol Oncol ; 17(1): 51-63, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9490320

RESUMO

Scanning electron microscopic studies of the gills of catfish, Heteropneustes fossilis, exposed to sublethal malathion (4 mg/L and 6 mg/L) revealed that 24-hour exposure to 4 mg/L had a mild effect. However, severe damage was found after 48- and 72-hour exposures. After a 24-hour exposure to a 6 mg/L concentration, more severe damage ensued. The microridged epithelial cells of the gill arch became perforated and the central portion of the filament appeared elevated. Numerous mucous gland openings also became visible. After 48- and 72-hour exposures, the damage and structural changes were more pronounced when compared with the 4 mg/L exposure. Enlarged mucous gland openings were found on the gill arch. The lamellar surface had many crevices, elevations and depressions. Broken microridges in the gill arch surface were visible at a 72-hour exposure. At 96 hours of exposure, structural recovery occurred to some extent in both the 4- and 6-mg/L exposures. Corrugation and dissociated epithelium along with some interlamellar bridges were evident after 72 hours of exposure to both concentrations. Such deleterious effects cause reduction in available water supply as well as available respiratory area that may result in decreased oxygen uptake. Consequently, fish may fail to get sufficient oxygen and asphyxiate.


Assuntos
Peixes-Gato , Brânquias/efeitos dos fármacos , Inseticidas/toxicidade , Malation/toxicidade , Animais , Brânquias/ultraestrutura , Microscopia Eletrônica de Varredura , Poluentes Químicos da Água
6.
J Environ Pathol Toxicol Oncol ; 18(1): 79-83, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-9951843

RESUMO

The use of pesticides to control pests and to increase food production is a normal process in this modern age. The objective of this study was to determine changes in different serum protein fractions caused by the action of malathion, a commonly used pesticide. We used Indian catfish, Heteropneustes fossilis. The fish were exposed to a sublethal dose of 4 mg/L of malathion for 24, 48, 72, and 96 hr. The LC50 value at 96 hr was found to be 11.676 mg/L. The results showed the formation of three low and four high mobility fractions and the disappearance of some protein fractions at different periods of exposure. The appearance of fractions A, B, and C (low-mobility proteins) may be due to altered immune responses caused by cellular damage. The appearance of new high-mobility fractions (D, E, F, and G) is possibly due to the breakdown of red blood cells and other cellular components. The findings of this study indicate that the high concentration of malathion (4 mg/L) induced more alterations in serum proteins compared with the low concentration (1.2 mg/L) used in our previous study.


Assuntos
Proteínas Sanguíneas/efeitos dos fármacos , Inseticidas/toxicidade , Malation/toxicidade , Animais , Peixes-Gato , Eletroforese
7.
Environ Pollut ; 125(3): 355-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12826413

RESUMO

A histopathological analysis of the testis exposed to diazinon, an organophosphorus pesticide was conducted. The testis from the control fish exhibited a normal histological structure with a round, oval or somewhat rectangular shaped with closely associated seminiferous tubules. The seminiferous tubules were surrounded by a layer of connective tissue with myoid cells, Leydig cells, blood vessels, lymph vessels and nerves. Upon exposure for 24 h, the overall structure of the testis looked disrupted and more often the sperm cells appeared to be somewhat larger, but spermatid were smaller than that of the control group. The 48 h exposure caused more dense and closely associated seminiferous tubules. The 72 h exposure induced dilation of the seminiferous tubules and their lumen. Ninety-six hours exposure induced more loose and disrupted structures. In this group (96 h), there was a significant reduction in both lumen and seminiferous tubule size in comparison with the control, 24, 48, and 72 h groups. After 2 weeks of exposure hardly any lumen was seen, which imparted more dense and compacted structures. The biometric analysis gave a highly significant increase in the diameter of the seminiferous lumen. After 48 h of exposure a significant reduction was seen in diameter in comparison with that of the control group. Seventy-two hour exposure indicated an increase in diameter, whereas 96 h exhibited another decrease. One week caused the diameter to increase whereas 2 weeks of exposure caused them to decrease again. The increase in diameter of the seminiferous tabule may be caused by weakening of the surrounding connective tissue and myoid cells, due to exposure to diazinon. The change in the diameters of the seminiferous tabules was very irregular. No apparent co-relation was found between the size of the fish, body weight and weight of the testis after they have been subjected to different exposure periods. There was significant change in the germ cells' diameters. As the germ cells are the essential first step in the process of spermatogenesis, their size reduction may hinder the production of viable spermatozoa, endangering the population dynamics. In order to find out the pathways of this pesticide effects, we propose to study the histopathology of pituitary gland a vital organ of the reproductive axis.


Assuntos
Diazinon/toxicidade , Inseticidas/toxicidade , Perciformes/anatomia & histologia , Testículo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biometria , Peso Corporal/efeitos dos fármacos , Inibidores da Colinesterase/toxicidade , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/patologia , Testículo/patologia
8.
Environ Pollut ; 92(3): 329-41, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-15091386

RESUMO

Transmission electron microscopy study of the gills of Heteropneustes fossilis, exposed to 4 mg/liter of malathion (1/3 of LC50) for 24, 48, 72, and 96 h showed significant changes in its ultrastructures. Exposure to the pesticide after 24 h caused a slightly disarrayed condition in the double layered epithelial structure. Lymphatic spaces became more apparent, and a few chloride cells appeared which protruded toward the peripheral margin of the secondary lamellae. Chloride cells were exposed to the exterior by an apical pit. Pinocytosis was observed with marginal folds (MF) originating from the pillar and epithelial cells. Some vascular constrictions were also seen in the capillaries with erythrocytes. After 48 h exposure, the outer epithelial cells were stretched into a thin boundary wall and lymphatic spaces were engorged with plasma exudate. Chloride cells transversed the whole epithelium of the lamella and came into direct contact with lymphoid space and exterior to epithelial lining. Basement membrane of the capillaries became thicker. After 72 h a distorted lamellar epithelium ruptured in a few places allowing many spheroid bodies and some chloride cells come out. Marginal folds of pillar cells migrated into vascular spaces. Basement membrane of capillaries became thicker and blood channels were constricted causing vascular stasis. No erythrocytes were visible. Blood channels were filled with leukocytes and amoebocytes. After 96 h exposure to malathion narrowing of lymphatic spaces, proliferation of epithelial cells and development of pinocytotic vesicles from marginal folds of pillar cell flanges were observed. Only marginal blood channels maintained normal configuration. Vascular stasis due to thickening of the basal lamina were still evident in centrally located blood channels filled with leukocytes. Vascular stasis would likely cause a decrease in respiratory efficiency. This study has revealed that the gills of H. fossilis were affected by a sublethal dose of malathion. The ultrastructural damages to the gills were observed as early as at 24 h exposure, but the most severe damage occurred at 72 h exposure. However, signs of gill structure regeneration were seen in malathion-exposed fish after 96 h.

9.
J Pediatr Surg ; 35(3): 438-41, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10726684

RESUMO

BACKGROUND/PURPOSE: Histopathologic examination of the esophagus has not been reported often in esophageal atresia (EA) and tracheoesophageal fistula (TEF). Abnormal esophageal motility has been reported after successful repair of EA and TEF, although the exact etiology of this motility disorder remains unclear. Histological evaluation of the fistulous portion of the esophagus has been performed to document any abnormality that may be responsible for the abnormal motility. METHODS: Histopathological study of fistulous segment of esophageal atresia and distal TEF was conducted on 65 patients, which included autopsy material from 3 patients in whom the entire esophagus was examined by serial section. Special stains were administered to each specimen to look for tracheobronchial remnants and the arrangement of muscle fibers. Clinical evaluation was performed in 27 patients who were available for review 6 months to 9 years after successful surgical treatment. These patients were categorized into 3 groups according to their clinical status. RESULTS: These findings showed that the majority of these patients have tracheobronchial remnants in the esophagus in the form of abnormal mucous glands and ducts, abnormal mucin secretion, presence of cartilage, and a disorganized muscle coat. CONCLUSIONS: The presence of abnormal mucous glands and abnormal mucin secretion has not been highlighted before. Although tracheobronchial remnants and a disorganized muscle coat are common findings in the fistulous portion of the esophagus, these may not reflect the structure of the remaining esophagus.


Assuntos
Atresia Esofágica/patologia , Esôfago/patologia , Fístula Traqueoesofágica/patologia , Biópsia , Atresia Esofágica/cirurgia , Esôfago/anormalidades , Humanos , Fístula Traqueoesofágica/cirurgia
10.
Eur J Pediatr Surg ; 11(6): 371-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11807665

RESUMO

Symptoms related to esophageal dysmotility are common following successful repair of esophageal atresia (EA) and tracheo-esophageal fistula (TEF). Esophageal manometry was performed in 27 survivors of EA/TEF at a mean age of 30.5 +/- 30.3 months and in 25 age-matched controls (mean age 36.8 +/- 22.6 months). The patients were also evaluated clinically to grade them into 3 result-oriented groups "Excellent", "Good" and "Fair", depending on pre-existing criteria evaluating the ability and ease of swallowing. Gastroesophageal reflux (GER) was evaluated with the help of a radionuclide scan. The mean esophageal and peak esophageal pressures and therefore also the lower esophageal sphincter (LES) pressure were lower in the patients (12.4 +/- 5.5, 34.9 +/- 20.4 and 12.2 +/- 6.8 mm Hg, respectively) compared to the controls (21.1 +/- 6.9, 62.3 +/- 19.3 and 16.8 +/- 4.3 mm Hg, respectively). The mean body pressures were highest with "Excellent" results and lowest with "Fair" results and the LES pressures followed a similar trend. Likewise, in the patients with GER, LES pressure was 12.0 +/- 7.1, 12.3 +/- 3.7, 11.0 +/- 5.7 and 6.9 +/- 5.6 mm Hg with nil, mild, moderate and severe GER, respectively. The pressure and contractility profile of the esophagus was abnormal in the majority of patients, even in the absence of symptoms.


Assuntos
Atresia Esofágica/cirurgia , Refluxo Gastroesofágico/etiologia , Complicações Pós-Operatórias/etiologia , Fístula Traqueoesofágica/cirurgia , Estudos de Casos e Controles , Pré-Escolar , Atresia Esofágica/complicações , Transtornos da Motilidade Esofágica/etiologia , Transtornos da Motilidade Esofágica/fisiopatologia , Humanos , Lactente , Manometria/métodos , Complicações Pós-Operatórias/fisiopatologia , Fístula Traqueoesofágica/complicações
11.
Indian J Exp Biol ; 31(1): 21-5, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8500812

RESUMO

Phospholipid content of whole blood lipid decreases significantly when goat blood is incubated for different length of time with different amebicidal agents (e.g., emetine, metronidazole and diloxanide furoate). The plots of relative per cent phosphate loss against incubation period show biphasic nature and suggest that the rates of phospholipid loss bears some relation with the drug's lipophilicity (log P in 1 octanol/water system). The absolute phospholipid loss seems to be governed by the drug's aquasolubility. Implication of these finding were discussed in terms of their clinical profiles assuming that the loss of phospholipid is due to drug's binding with the phospholipid layer in amebic cyst-coat, being the first step which may trigger a chain of events leading to the onset of drug action.


Assuntos
Amebicidas/farmacologia , Fosfolipídeos/sangue , Animais , Emetina/farmacologia , Furanos/farmacologia , Cabras , Técnicas In Vitro , Metronidazol/farmacologia , Solubilidade
12.
Indian J Pediatr ; 64(6 Suppl): 48-56, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-11129881

RESUMO

The present study is an analysis of 747 patients with hydrocephalus, treated and followed up in the Hydrocephalus Clinic run by the department of Paediatric Surgery at the All India Institute of Medical Sciences, New Delhi. The distribution of patients was: congenital-46%, post-meningomyelocoele excision-28%, post-meningitic-21% and others-5% (including post haemorrhagic and post encephalocoele excision hydrocephalus. The average age was 7 months in the shunted group and 10 months in the medical group with overall male to female ratio of 2.3:1. The data were analysed to study the effect of treatment on ventriculomegaly and mental development with special reference to the type of treatment (shunt versus medical) and age at starting treatment. The probability of shunt failure was also studied. A comparison of ventricular size in US/CAT scans between the time of starting treatment and last follow-up revealed improvement in ventriculomegaly in 60% of the shunted patients but only 30% of the medically treated patients. A significant difference was particularly noted in patients with severe hydrocephalus, 72% and 22%, respectively. Comparison of the mean Mental Performance Quotient (MPQ) scores in the shunted & medically treated patients also revealed significantly better MPQ scores in the shunted group (p = < 0.001). Probability of shunt survival, as depicted by the Kaplan-Meier survival curve, revealed that there is a high rate of shunt failure in the first 12 months, followed by a dramatic slowing down. Our observations support the contention that CSF shunt surgery offers better outcome than medical management even when ventriculomegaly is severe at the time of presentation.


Assuntos
Derivações do Líquido Cefalorraquidiano , Hidrocefalia/terapia , Ventrículos Cerebrais/patologia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Pré-Escolar , Feminino , Seguimentos , Humanos , Hidrocefalia/classificação , Hidrocefalia/diagnóstico , Hidrocefalia/etiologia , Hipertrofia , Lactente , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/etiologia , Testes de Inteligência , Masculino , Seleção de Pacientes , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
Indian J Biochem Biophys ; 33(1): 76-80, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8744839

RESUMO

Two cardiac glycosides, namely digitoxin and digoxin when treated with goat blood, were found to alter the lipid constitution as measured by their phosphorus content, fatty acid composition and malonaldehyde content. There was significant increase in the poly-unsaturated fatty acids (PUFA) and malonaldehyde contents in blood treated with these drugs. Possible correlation between the lipophilicity of the drugs and their biological activity is discussed.


Assuntos
Cardiotônicos/farmacologia , Digitoxina/farmacologia , Digoxina/farmacologia , Lipídeos/sangue , Animais , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos Insaturados/sangue , Cabras , Malondialdeído/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/análise
14.
Indian J Biochem Biophys ; 28(3): 210-3, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1786972

RESUMO

To correlate lipophilicity of lignocaine with changes in lipid composition of blood as a result of in vitro incubation with the drug, phosphorus content and fatty acid compositions of blood lipids before and after lignocaine treatment have been compared with those of a standard phospholipid, lecithin, under similar conditions of drug treatment. The change in fatty acid constituents has been correlated with the biological activity (both therapeutic and toxic) of lignocaine.


Assuntos
Lidocaína/farmacologia , Lipídeos/sangue , Animais , Cromatografia Gasosa , Cromatografia em Camada Fina , Ácidos Graxos/análise , Ácidos Graxos não Esterificados/sangue , Cabras , Lipídeos/isolamento & purificação , Fosfolipídeos/sangue
15.
Indian J Biochem Biophys ; 30(2): 128-32, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8354520

RESUMO

Considering the high lipophilicity of propranolol (log P = 3.56), its interactions with the cell membrane lipids of goat blood have been investigated. It is observed that lipid loss after incubation of blood cells with propranolol hydrochloride in salt glucose medium for varying periods of time was accompanied with significant increases in PUFAs. Amongst the PUFAs studied the omega 3 and omega 6 fatty acids, the two important precursors of eicosenoids, have shown increase in varying amounts. This phenomenon is presumably responsible for the significant cardiovascular activity of this drug.


Assuntos
Lipídeos/sangue , Propranolol/farmacologia , Animais , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Ácidos Graxos/sangue , Cabras , Técnicas In Vitro
16.
Nepal J Ophthalmol ; 4(1): 68-72, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22344000

RESUMO

INTRODUCTION: Mitomycin C is gaining widespread popularity as an adjunctive with trabeculectomy, as it significantly increases the success rate of the procedure. But it is associated with serious sight-threatening complications. MATERIALS AND METHODS: Twenty eyes planned for trabeculectomy from the glaucoma clinic were enrolled for the study after obtaining an informed consent. The baseline impression cytology was taken. Ten eyes underwent trabeculectomy with mitomycin C (Group A) and the rest underwent trabeculectomy without any antimetabolites (Group B). Impression cytology samples were taken on months 1, 3, 6, 9 and 12. RESULTS: In Group A, the difference between goblet cell density preoperatively and 12 month postoperatively was statistically significant (p less than 0.0001). In Group B, the difference was not statistically significant. (p = 0.27). CONCLUSION: Mitomycin C, though used to augment the success rate of trabeculectomy, has deleterious effect on the conjunctival goblet cell population as is evident from the conjunctival impression cytology.


Assuntos
Túnica Conjuntiva/patologia , Glaucoma/cirurgia , Células Caliciformes/efeitos dos fármacos , Mitomicina/farmacologia , Trabeculectomia/métodos , Adulto , Idoso , Antibióticos Antineoplásicos/farmacologia , Contagem de Células , Túnica Conjuntiva/efeitos dos fármacos , Feminino , Seguimentos , Glaucoma/patologia , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade
19.
Ecotoxicol Environ Saf ; 60(1): 21-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15482836

RESUMO

An attempt to reveal endocrine disruption in bluegill fish (Lepomis macrochirus) upon exposure to diazinon was made. Fish blood serum was collected and estradiol levels were measured following times of exposure to 60 microg/L of diazinon. Samples were drawn from the fish during each exposure period of 24, 48, 72 and 96 h and 1 and 2 weeks. The sample estradiol levels were compared to those of a control. Ovarian tissue was examined. As necrosis increased within the ovaries, estradiol blood serum levels altered from those of the control sample (101 pg/mL). Histopathology within the follicles became apparent as exposure time to diazinon increased. The changes in the ovarian follicles can be correlated to the estradiol levels in the blood. Mean estradiol level for the control group was 101.53 pg/mL. Estradiol levels from the trial groups varied from those of the control (24 h, undetectable; 48 h, 74.04 pg/mL; 72 h, 57.16 pg/mL; 96 h; 39.15 pg/mL; 1 week, 66.50 pg/mL; 2 weeks, undetectable). It seems that the initial shock experienced by the fish after 24 h of exposure resulted in an undetectable level of estradiol. The level of estradiol initially ascended, but it began to decline and after 1 week of exposure it ascended a little and became undetectable after 2 weeks. Nevertheless, throughout the exposure period the level of estradiol was lower than normal. Severe damage to the mature oocytes may be the reason for undetectable levels of estradiol after 2 weeks of exposure.


Assuntos
Diazinon/intoxicação , Sistema Endócrino/efeitos dos fármacos , Exposição Ambiental , Inseticidas/intoxicação , Ovário/efeitos dos fármacos , Ovário/patologia , Perciformes/fisiologia , Animais , Estradiol/sangue , Feminino , Necrose , Oócitos/efeitos dos fármacos , Oócitos/fisiologia
20.
Gerontology ; 40(2-4): 97-112, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7926860

RESUMO

Fishes exhibit a 'determinate' type of growth in short-lived species of warmer regions and an 'indeterminate' type in long-lived species of colder regions. Growth is measured in units of length and weight and is best represented as the specific growth rate. The relationship between weight and length provides an index of the state of well-being of a fish (condition factor 'K'). Growth could also be measured by using certain other criteria such as glycine uptake by scales, hepatosomatic index, RNA:DNA ratio and protein retention in the tissues. Nutrition, including the quality and quantity of food, plays a significant role in growth regulation. A number of environmental factors, such as temperature, oxygen concentration, salinity and photoperiod, influence the rate of growth. Recent data suggest that genotypes, hormones and physiological conditions of the individual are also equally important endogenous regulators of growth.


Assuntos
Peixes/crescimento & desenvolvimento , Envelhecimento/genética , Envelhecimento/patologia , Envelhecimento/fisiologia , Animais , Dieta , Meio Ambiente , Feminino , Peixes/genética , Peixes/fisiologia , Glicina/metabolismo , Hormônios/fisiologia , Masculino , Comportamento Social , Temperatura
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