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31.
32.
Yadav Jyoti Verma Anoop Kumar Ahmad Md. Kaleem Garg Ravindra K. Shiuli Mahdi Abbas Ali Srivastava Shrikant 《Molecular biology reports》2021,48(4):3245-3252
Molecular Biology Reports - Alzheimer's disease is a common neurodegenerative disease in the elderly population and a leading cause of dementia. Genetics and environmental risk factors were... 相似文献
33.
Pradeep Koppolu Sunkara Sirisha Ashank Mishra Kopparesh Deshpande Amara Swapna Lingam Dalal H. Alotaibi Mohammed Saleh Alwahibi Soumya Penela 《Saudi Journal of Biological Sciences》2021,28(1):380-385
Periodontitis is commonly diagnosed based on clinical parameters. However, the analysis of a few unique biomarkers of the disease process present in the saliva and blood can further assist the estimation of the rate of disease progression.AimThe present study attempted to correlate the alkaline phosphatase (ALP) and acid phosphatase (ACP) levels in saliva and serum between patients with healthy periodontium, gingivitis, and chronic periodontitis.Materials and methodsThe present study was conducted in 135 subjects between 20 and 55 years of age. The subjects were divided into three groups, namely healthy (Group A), gingivitis (Group B), and chronic periodontitis (Group C). The clinical parameters were recorded using the plaque index (PI), gingival index (GI), and probing depth (PD). Saliva and serum were analyzed for ALP and ACP levels using an auto analyzer. All patients underwent scaling and root planning (SRP) along with oral hygiene instructions. Patients were then recalled after four weeks, and blood and saliva samples were collected to estimate ALP and ACP levels prior to clinical examination.ResultsThe clinical parameters exhibited a statistically significant decrease in the PI and GI in both group B and group C after SRP. A significant change in the PD and attachment levels (AL) was observed in the periodontitis group after SRP. The mean salivary & serum ALP levels exhibited a statistically significant decrease in group B & C after SRP. The mean serum ACP levels exhibited a statistically significant decrease in group B & C after SRP However, the salivary ACP levels decrease after SRP was only statistically significant in group C.ConclusionSerum and salivary ALP and ACP levels were markedly decreased in the gingivitis and periodontitis groups after SRP and were positively correlated with the clinical parameters. 相似文献
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Xavier Fioramonti Adam Deak Srinidhi Deshpande Lionel Carneiro Chunxue Zhou Nazish Sayed Branly Orban Joshua R. Berlin Luc Pénicaud Corinne Leloup Annie Beuve Vanessa H. Routh 《PloS one》2013,8(7)
Aims
Hypoglycemia is a severe side effect of intensive insulin therapy. Recurrent hypoglycemia (RH) impairs the counter-regulatory response (CRR) which restores euglycemia. During hypoglycemia, ventromedial hypothalamus (VMH) production of nitric oxide (NO) and activation of its receptor soluble guanylyl cyclase (sGC) are critical for the CRR. Hypoglycemia also increases brain reactive oxygen species (ROS) production. NO production in the presence of ROS causes protein S-nitrosylation. S-nitrosylation of sGC impairs its function and induces desensitization to NO. We hypothesized that during hypoglycemia, the interaction between NO and ROS increases VMH sGC S-nitrosylation levels and impairs the CRR to subsequent episodes of hypoglycemia. VMH ROS production and S-nitrosylation were quantified following three consecutive daily episodes of insulin-hypoglycemia (RH model). The CRR was evaluated in rats in response to acute insulin-induced hypoglycemia or via hypoglycemic-hyperinsulinemic clamps. Pretreatment with the anti-oxidant N-acetyl-cysteine (NAC) was used to prevent increased VMH S-nitrosylation.Results
Acute insulin-hypoglycemia increased VMH ROS levels by 49±6.3%. RH increased VMH sGC S-nitrosylation. Increasing VMH S-nitrosylation with intracerebroventricular injection of the nitrosylating agent S-nitroso-L-cysteine (CSNO) was associated with decreased glucagon secretion during hypoglycemic clamp. Finally, in RH rats pre-treated with NAC (0.5% in drinking water for 9 days) hypoglycemia-induced VMH ROS production was prevented and glucagon and epinephrine production was not blunted in response to subsequent insulin-hypoglycemia.Conclusion
These data suggest that NAC may be clinically useful in preventing impaired CRR in patients undergoing intensive-insulin therapy. 相似文献36.
Lucy A. Jury Brett Sitzlar Sirisha Kundrapu Jennifer L. Cadnum Kim M. Summers Christine P. Muganda Abhishek Deshpande Ajay K. Sethi Curtis J. Donskey 《PloS one》2013,8(7)
Background
Recent reports suggest that community-associated Clostridium difficile infection (CDI) (i.e., no healthcare facility admission within 90 days) may be increasing in frequency. We hypothesized that outpatient clinics could be an important source for acquisition of community-associated CDI.Methods
We performed a 6-month prospective study of CDI patients to determine frequency of and risk factors for skin and environmental shedding during outpatient visits and to derive a prediction rule for positive cultures. We performed a point–prevalence culture survey to assess the frequency of C. difficile contamination in outpatient settings and evaluated the frequency of prior outpatient visits in patients with community-associated CDI.Results
Of 67 CDI patients studied, 54 (81%) had 1 or more outpatient visits within 12 weeks after diagnosis. Of 44 patients cultured during outpatient visits, 14 (32%) had skin contamination and 12 (27%) contaminated environmental surfaces. Decreased mobility, fecal incontinence, and treatment with non-CDI antibiotics were associated with positive cultures, whereas vancomycin taper therapy was protective. In patients not on CDI therapy, a prediction rule including incontinence or decreased mobility was 90% sensitive and 79% specific for detection of spore shedding. Of 84 clinic and emergency department rooms cultured, 12 (14%) had 1 or more contaminated environmental sites. For 33 community-associated CDI cases, 31 (94%) had an outpatient visit during the 12 weeks prior to onset of diarrhea.Conclusions
Patients with recent CDI present a significant risk for transmission of spores during outpatient visits. The outpatient setting may be an underappreciated source of community-associated CDI cases. 相似文献37.
Ariopsis macrosperma sp. nov. from Western Ghats of Maharashtra, India, is described and illustrated. It differs from the other two species in the genus, A. peltata and A. protanthera, in having a typical terrestrial habit, growing on the soil as undergrowth below the forest canopy, thick, leathery leaves and lower number of larger, ovoid and ribbed seeds. 相似文献
38.
Biological nitrification inhibition (BNI) activity in sorghum and its characterization 总被引:5,自引:0,他引:5
G. V. Subbarao K. Nakahara T. Ishikawa H. Ono M. Yoshida T. Yoshihashi Yiyong Zhu H. A. K. M. Zakir S. P. Deshpande C. T. Hash K. L. Sahrawat 《Plant and Soil》2013,366(1-2):243-259
Aims
The ability to suppress soil nitrification through the release of nitrification inhibitors from plant roots is termed ‘biological nitrification inhibition’ (BNI). Here, we aimed at the quantification and characterization of the BNI function in sorghum that includes inhibitor production, their chemical identity, functionality and factors regulating their release.Methods
Sorghum was grown in solution culture and root exudate was collected using aerated NH4Cl solutions. A bioluminescence assay using recombinant Nitrosomonas europaea was employed to determine the BNI activity. Activity-guided chromatographic fractionation was used to isolate biological nitrification inhibitors (BNIs). The chemical structure was analyzed using NMR and mass spectrometry; pH-stat systems were deployed to analyze the role of rhizosphere pH on BNIs release.Results
Sorghum roots released two categories of BNIs: hydrophilic- and hydrophobic-BNIs. The release rates for hydrophilic- and hydrophobic- BNIs ranged from 10 to 25 ATU?g?1 root dwt. d?1. Addition of hydrophilic BNIs (10 ATU?g?1 soil) significantly inhibited soil nitrification (40 % inhibition) during a 30-d incubation test. Two BNI compounds isolated are: sakuranetin (ED80 0.6 μM; isolated from hydrophilic-BNIs fraction) and sorgoleone (ED80 13.0 μM; isolated from hydrophobic-BNIs fraction), which inhibited Nitrosomonas by blocking AMO and HAO enzymatic pathways. The BNIs release required the presence of NH 4 + in the root environment and the stimulatory effect of NH 4 + lasted 24 h. Unlike the hydrophobic-BNIs, the release of hydrophilic-BNIs declined at a rhizosphere pH >5.0; nearly 80 % of hydrophilic-BNI release was suppressed at pH ≥7.0. The released hydrophilic-BNIs were functionally stable within a pH range of 5.0 to 9.0. Sakuranetin showed a stronger inhibitory activity (ED50 0.2 μM) than methyl 3-(4-hydroxyphenyl) propionate (MHPP) (ED50 100 μM) (isolated from hydrophilic-BNIs fraction) in the in vitro culture-bioassay, but the activity was non-functional and ineffective in the soil-assay.Conclusions
There is an urgent need to identify sorghum genetic stocks with high potential to release functional-BNIs for suppressing nitrification and to improve nitrogen use efficiency in sorghum-based production systems. 相似文献39.
Shrikant Mali 《Indian journal of human genetics》2013,19(1):3-8
The structure of DNA was unraveled by Watson and Crick in 1953, and two decades later Arber, Nathans and Smith discovered DNA restriction enzymes, which led to the rapid growth in the field of recombinant DNA technology. From expressing cloned genes in bacteria to expressing foreign DNA in transgenic animals, DNA is now slated to be used as a therapeutic agent to replace defective genes in patients suffering from genetic disorders or to kill tumor cells in cancer patients. Gene therapy provides modern medicine with new perspectives that were unthinkable two decades ago. Progress in molecular biology and especially, molecular medicine is now changing the basics of clinical medicine. A variety of viral and non-viral possibilities are available for basic and clinical research. This review summarizes the delivery routes and methods for gene transfer used in gene therapy. 相似文献
40.
Ayan Dey Natalie A. Molodecky Harish Verma Prashant Sharma Jae Seung Yang Giulietta Saletti Mohammad Ahmad Sunil K. Bahl Thomas F. Wierzba Ranjan K. Nandy Jagadish M. Deshpande Roland W. Sutter Cecil Czerkinsky 《PloS one》2016,11(1)