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61.
Faheem Shah Tasneem Gul Kazi Hassan Imran Afridi Naveed Kazi Jameel Ahmed Baig Abdul Qadir Shah Sumaira Khan Nida Fatima Kolachi Sham Kumar Wadhwa 《Biological trace element research》2011,141(1-3):131-149
Anemia affects a substantial portion of the world’s population, provoking severe health problems as well as important economic losses to the region in which this condition is found. This study was designed to compare the levels of essential trace and toxic elements in scalp hair, blood, and urine samples of anemic children (n = 132) with age range 1–5 and 6–10 years of both genders. For a comparative study, 134 non-anemic age- and sex-matched children as control subjects, residing in the same city, were selected. The metals in the biological samples were measured by flame atomic absorption spectrophotometry/electrothermal atomic absorption spectrometry prior to microwave-assisted acid digestion. The proposed method was validated using certified reference samples of hair, blood, and urine. The results indicated significantly lower levels of iron, copper, and zinc in the biological samples as compared to the control children of both genders (p = 0.01–0.008). The mean values of lead and cadmium were significantly high in all three biological samples of anemic children as compared to non-anemic children of both age groups (p = 0.005–0.001). The ratios of essential metal to toxic metals in the biological samples of anemic children of both age groups were significantly lower than that of controls. Deficiency of essential trace metals and high level of toxic metals may play a role in the development of anemia in the subjects under study. 相似文献
62.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Sirajuddin Ghulam Abbas Kandhro Jameel Ahmed Baig Abdul Qadir Shah Mohammad Khan Jamali Mohammad Balal Arain Sham Kumar Wadhwa Sumaira Khan Nida Fatima Kolachi Faheem Shah 《Biological trace element research》2011,142(3):259-273
It has been speculated that trace elements may play a role in the pathogenesis of heart diseases In the present study, we aimed to access the levels of chromium (Cr) and manganese (Mn) in biological samples (whole blood, urine, and scalp hair) of myocardial infarction (MI) patients of both gender age ranged (45?C60?years) at first, second, and third heart attack (n?=?130), hospitalized in cardiac ward of National Hospital of Hyderabad city (Pakistan). For comparison, healthy age-matched referent subjects (n?=?61), of both gender were also selected. The Cr and Mn in biological samples were measured by electrothermal atomic absorption spectrometry, prior to microwave-assisted acid digestion. The validity of the methodology was checked by the biological certified reference materials. During this study, 78% of 32 registered patients of third MI attack (aged >50?years) were died. In these subjects the concentration of Cr and Mn were decreased by 24.7% and 19.8% in scalp hair, while in blood samples 17.9% and 12.4%, respectively, as compared to those who tolerated third MI attack (p?=?0.063). Although these data do not prove a causal relationship, these results are consistent with the hypothesis that heart disease may cause deficiencies of certain essential trace elements. The excretion levels of Cr and Mn in urine samples of first MCI were higher than controls at p values (0.029 and 0.011), respectively, whereas the excretion rates of both elements were further enhance after second myocardial infarction attack. The Cr and Mn concentration was inversely associated with the risk of myocardial infarction attacks in both genders. These results add to an increasing body of evidence that, Cr and Mn are importance for cardiovascular health. 相似文献
63.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Jameel Ahmed Baig Abdul Qadir Shah Sham Kumar Wadhwa Sumaira Khan Nida Fatima Kolachi Faheem Shah Mohammad Khan Jamali Mohammad Balal Arain Sirajuddin 《Biological trace element research》2011,143(1):20-40
The most common cause of blindness in developing countries is vitamin A deficiency. The World Health Organization estimates 13.8 million children to have some degree of visual loss related to vitamin A deficiency. The causes of night blindness in children are multifactorial, and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological samples composition. Vitamin and mineral deficiency prevents more than two billion people from achieving their full intellectual and physical potential. This study was designed to compare the levels of Zn, Mg, Ca, K, Na, As, Cd, and Pb in scalp hair, blood, and urine of night blindness children age ranged 3–7 and 8–12 years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure was developed as a sample pretreatment, for the determination of As, Ca, Cd, K, Pb, Mg, Na, and Zn in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood, and urine. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The results of this study showed that the mean values of As, Cd, Na, and Pb were significantly higher in scalp hair, blood, and urine samples of male and female night blindness children than in referents (p?<?0.001), whereas the concentrations of Zn, Ca, K, and Mg were lower in the scalp hair and blood but higher in the urine samples of night blindness children. These data present guidance to clinicians and other professional investigating deficiency of essential mineral elements in biological samples (scalp hair and blood) of night blindness children. 相似文献
64.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Abdul Qadir Shah Jameel Ahmed Baig Sham Kumar Wadhwa Sumaira Khan Nida Fatima Kolachi Faheem Shah Mohammad Khan Jamali Mohammad Balal Arain 《Biological trace element research》2011,143(1):103-115
This study was designed to compare the levels of chromium (Cr) and manganese (Mn) in scalp hair, blood, and urine of night blindness in children age ranged (3–7) and (8–12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure, was developed as a sample pretreatment, for the determination of Cr and Mn in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood and urine. The digests of all biological samples were analyzed for Cr and Mn by electrothermal atomic absorption spectrometry. The results indicated significantly higher levels of Cr, whilst low level of Mn in the biological samples (blood and scalp hair) of male and female night blindness children, compared with control subjects of both genders. These data present guidance to clinicians and other professional investigating deficiency of Mn and excessive level of Cr in biological samples (scalp hair and blood) of night blindness children. 相似文献
65.
Nida Fatima Kolachi Tasneem Gul Kazi Hassan Imran Afridi Naveed Kazi Ghulam Abbas Kandhro Abdul Qadir Shah Jameel Ahmed Baig Sham Kumar Wadhwa Sumaira Khan Faheem Shah Mohammad Khan Jamali Mohammad Balal Arain 《Biological trace element research》2011,143(1):116-130
The aim of the present study was to compare the level of copper (Cu), iron (Fe) and zinc (Zn) in biological samples (serum, blood, urine, and scalp hair) of patients suffering from different viral hepatitis (A, B, C, D, and E; n?=?521) of both gender age ranged 31–45 years. For comparative study, 255 age-matched control subjects, of both genders residing in the same city were selected as referents. The elements in the biological samples were analyzed by flame atomic absorption spectrophotometry, prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked by using certified reference materials (CRMs) and with those values obtained by conventional wet acid digestion method on same CRMs. The results of this study showed that the mean values of Cu and Fe were higher in blood, sera, and scalp hair samples of hepatitis patients, while Zn level was found to be lower than age-matched control subjects. The urinary levels of these elements were found to be higher in the hepatitis patients than in the age-matched healthy controls (p?<?0.05). These results are consistent with literature-reported data, confirming that the deficiency of zinc and hepatic iron and copper overload can directly cause lipid peroxidation and eventually hepatic damage. 相似文献
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68.
Dipl. Geol. Volker Thiel Dr. Martina Merz-Preiß Prof. Dr. Joachim Reitner PD Dr. Walter Michaelis 《Facies》1997,36(1):163-172
Summary Biomarker investigations are applied to the free lipid fractions of a naturally grown freshwater microbial mat, constructed
by calcifying cyanobacteria (Scytonema sp. andSchizothrix sp.). The absolute and relative concentrations of hydrocarbons, free alcohols and carboxylic acids are studied and their
probable biological precursors are discussed. A significant signal of cyanobacterial lipids is recognized by the strong predominance
ofn-heptadecane (C17),n-heptadecene, two monomethyl-heptadecanes, and the pentacyclic triterpenoid diploptene. Their occurrences parallel the lipid
distributions found in pure cultured cyanobacteria and in recent cyanobacterial mats grown in particular environments (hypersaline,
lagoonal, hot spring). The observed compound signature appears to be a suitable reference for environments, where cyanobacteria
are directly associated with theloci of carbonate precipitation and thus, rock formation. In the studied material, a significant contribution of organic matter
from other sources, especially higher plants is characterized by the occurrence of several specific marker compounds, namely
lup-20(29)-ene-3-ol, high molecular weightn-alkanes and carboxylic acids. Although these components comprise a notably high portion of the sample’s lipid inventory,
they are shown to be distinguished easily from the signal left by the predominant mat building organisms. 相似文献
69.
A method was devised for the removal of deleterious minerals and metals from high ash-containing Indian coals. A selective
enriched mixed culture developed for this purpose was used for stepwise aerobic bioleaching of two high ash Indian bituminous
coals (Topa coal and Godavari coal) and Neyveli lignite. The process of bioleaching resulted in the removal of more than 50%
of the mineral matter in five repeated steps and thus produced relatively demineralized, clean coal. Various parameters were
optimized for bioleaching in order to maximize the removal of mineral matter. Based on the above studies a two-step pilot
experiment was conducted under optimum conditions. The results obtained indicated removal of 75% of the mineral matter from
one of the coals. The changes in mineral matter composition of these coals were evaluated using Fourier Transform Infra Red
(FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The results indicated a decrease in the intensity of many peaks
when seen in combination with the amount of mineral matter removed from the bioleached coals. The mechanism of the bioleaching
process is discussed and many uses of the clean coal produced are suggested. 相似文献
70.
Renu Wadhwa Didik Priyandoko Ran Gao Nashi Widodo Nupur Nigam Ling Li Hyo Min Ahn Chae-Ok Yun Nobuhiro Ando Christian Mahe Sunil C. Kaul 《Cell stress & chaperones》2016,21(4):631-644
In order to identify the cellular factors involved in human melanogenesis, we carried out shRNA-mediated loss-of-function screening in conjunction with induction of melanogenesis by 1-oleoyl-2-acetyl-glycerol (OAG) in human melanoma cells using biochemical and visual assays. Gene targets of the shRNAs (that caused loss of OAG-induced melanogenesis) and their pathways, as determined by bioinformatics, revealed involvement of proteins that regulate cell stress response, mitochondrial functions, proliferation, and apoptosis. We demonstrate, for the first time, that the mitochondrial stress chaperone mortalin is crucial for melanogenesis. Upregulation of mortalin was closely associated with melanogenesis in in vitro cell-based assays and clinical samples of keloids with hyperpigmentation. Furthermore, its knockdown resulted in compromised melanogenesis. The data proposed mortalin as an important protein that may be targeted to manipulate pigmentation for cosmetic and related disease therapeutics. 相似文献