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991.
D. Norouzian K. Rostami D. Nouri Inanlou M. Saleh 《World journal of microbiology & biotechnology》2000,16(2):155-161
Arthrobotrys amerospora ATCC 34468 produced glucoamylase in a medium containing maize starch as carbon source. On native PAGE, crude glucoamylase showed three isoenzymes which were designated as Glu I, Glu II, Glu III according to their electrophoretic mobility. These were purified by column chromatography techniques. The energy of binding for each glucoamylase was calculated using Hiromi's kinetic based calculation. At subsite 1, the binding energies for Glu I, II and III were found to be negative. 相似文献
992.
The phylogenetic positions of three systematically controversial genera of ciliates, Spirotrachelostyla, Uroleptopsis and Tunicothrix, have never been established by molecular data. The small subunit rRNA genes of three species, S. tani, U. citrina and T. wilberti, were sequenced and added to existing sequences of stichotrichs and other ciliates to construct phylogenetic trees. Results indicate the following: (1) Uroleptopsis is most closely related to species of Pseudokeronopsis, supporting its assignment to the family Pseudokeronopsidae; (2) one sampled Tunicothrix branches sister to the two sampled Parabirojimia, and this supports the placement of Tunicothrix in the Parabirojimidae; (3) Spirotrachelostyla clusters consistently with Trachelostyla to form a distinct, divergent clade that associates with Amphisiella at the base of the entire sporadotrich-urostylid clade, confirming the hypothesis that Spirotrachelostyla should be placed in the family Trachelostylidae. 相似文献
993.
994.
David V. Godin Saleh A. Wohaieb Maureen E. Garnett A. D. Goumeniouk 《Molecular and cellular biochemistry》1988,84(2):223-231
Previous studies from our laboratory have demonstrated the presence of complex alterations in the activities of antioxidant enzymes in various tissues of rats with streptozotocin (STZ)-induced diabetes. In the present investigation, it is shown that rats made diabetic with alloxan (ALX), an agent differing from STZ both chemically and in its mechanism of diabetogenesis, show virtually identical tissue antioxidant enzyme changes which, as is the case with STZ, are preventable by insulin treatment. The finding that the patterns of antioxidant enzyme alterations in chemically-induced diabetes are independent of the diabetogenic agent used and the presence of similar abnormalities in tissues of spontaneously diabetic (BB) Wistar rats (particularly when diabetic control is less than optimal) suggest that the changes observed are a characteristic feature of the uncontrolled diabetic state and that these may be responsible for (or predispose to) the development of secondary complications in clinical diabetes. Comparative studies involving red cells of diabetic rats and human diabetics revealed a number of common changes, namely an increase in glutathione reductase activity, a decreased susceptibility to oxidative glutathione depletion (which was related to the presence of hyperglycemia) and an increased production of malondialdehyde (an indirect index of lipid peroxidation) in response to in vitro challenge with hydrogen peroxide. In the diabetic patients, the extent of this increase in susceptibility of red cell lipids to oxidation paralleled the severity of diabetic complications. Our results suggest that increased (or uncontrolled) oxidative activity may play an important role in the pathogenesis of complications associated with the chronic diabetic state.This work was supported by grants from the British Columbia Health Care Research Foundation and the Canadian Diabetes Association. 相似文献
995.
996.
One hundred seventy-nine pregnant women, ages 15–45 yr, were divided into three groups. Group A was orally given one spansule
per day containing 150 mg dried ferrous sulfate, 61.8 mg zinc sulfate, and 500 μg folic acid, starting from the first 4 wk
of pregnancy and ending at the day of delivery. Similarly, group B was given one tablet containing 625 mg calcium carbonate,
1000 mg vitamin C, 300 IU Vitamin D, 1350 mg citric acid, and 15 mg Vitamin B6. Group C was without any supplements and served
as a control. Mothers who received iron/zinc supplements (group A) during pregnancy had significantly higher copper/zinc superoxide
dismutase activity in their placentae than calcium/vitamin-supplemented mothers (group B) or unsupplemented mothers (group
C). The enzyme activity increased with age of the mothers from 15 to 40 yr, then decreased after in both supplemented groups,
whereas this increase and decrease occurred at early age in the unsupplemented group. Immunochemical quantitation of the enzyme
contents showed no significant difference between the supplemented and unsupplemented groups, suggesting that the observed
increase in the enzyme activity might arise from posttranslational processing of the enzyme.
The placental manganese superoxide dismutase activity and contents, however, were similar in the supplemented groups, whereas
they were slightly higher in the unsupplemented group; the overall superoxide dismutase-like activities in the placentae were
the highest in iron-zinc supplemented group and the lowest in the unsupplemented group. 相似文献
997.
Mona Mohammed Saleh Al-Dawsary 《Saudi Journal of Biological Sciences》2014,21(3):275-279
This study deals with the analysis of the integument of the red palm weevil Rhynchophorus ferrugineus of both sexes using the GC–MS technique. The results of the study revealed many promising compounds. These include aspidofractinine-3-methanol (kopsinyl alcohol) which was found in the acetone extract of the sternum of females, and 3-buten-2-ol (32-B) which was found in the extracts of sternum and tergum of males. This compound the aggregation pheromone was secreted by males. Additionally, compounds with methoxy groups were found. These may be responsible for insects’ resistance. This study, through separation and identification of these compounds, aims to open a new possibility for their future medical and therapeutic usage. 相似文献
998.
999.
Warit Jithpratuck Yasmin Elshenawy Hana Saleh George Youngberg David S Chi Guha Krishnaswamy 《Clinical and molecular allergy : CMA》2011,9(1):1-7
Type 1 hyper IgE syndrome (HIES), also known as Job's Syndrome, is an autosomal dominant disorder due to defects in STAT3 signaling and Th17 differentiation. Symptoms may present during infancy but diagnosis is often made in childhood or later. HIES is characterized by immunologic and non-immunologic findings such as recurrent sinopulmonary infections, recurrent skin infections, multiple fractures, atopic dermatitis and characteristic facies. These manifestations are accompanied by elevated IgE levels and reduced IL-17 producing CD3+CD4+ T cells. Diagnosis in young children can be challenging as symptoms accumulate over time along with confounding clinical dilemmas. A NIH clinical HIES scoring system was developed in 1999, and a more recent scoring system with fewer but more pathogonomonic clinical findings was reported in 2010. These scoring systems can be used as tools to help in grading the likelihood of HIES diagnosis. We report a young child ultimately presenting with disseminated histoplasmosis and a novel STAT3 variant in the SH2 domain. 相似文献
1000.
Kamel Saleh Serap Celikler Mohammed A.A. Sarhan 《Saudi Journal of Biological Sciences》2010,17(4):311-314
In this study, a nereistoxin analogue insecticide, thiocyclam, was administered to adult male albino rats by gavage dose of 135, 270 and 540 mg/kg b.w. repeated for 5 days at 24 h intervals. Control animals received only water. Thiocyclam was tested for its potential to cause genotoxic effects in rat bone marrow cells using an in vivo micronucleus assay. After 24 h of the last treatment, rats from all dose levels were sacrificed. Bone marrow cells were collected and assayed for the presence of micronuclei. Thiocyclam did not cause any increase in the incidence of micronucleated polychromatic erythrocytes in rats bone marrow at any of the dose levels. The polychromatic erythrocytes/normochromatic erythrocytes (PCE:NCE) ratio was found to be in the range from 0.50 ± 0.11 to 0.55 ± 0.02. The results of this study demonstrate that the effect of thiocyclam is not significant in the rat in vivo micronucleus assay. 相似文献