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排序方式: 共有610条查询结果,搜索用时 15 毫秒
1.
Chakraborty S Garg P Ramamurthy T Thungapathra M Gautam JK Kumar C Maiti S Yamasaki S Shimada T Takeda Y Ghosh A Nair GB 《Journal of medical microbiology》2001,50(10):879-888
This study identified 17 matching serogroups of Vibrio cholerae belonging to serogroups other than O1 and O139 isolated from human cases and from the environment during a concurrent clinical and environmental study conducted in Calcutta, a cholera endemic area. Isolates within these matching serogroups were compared by various phenotypic and genotypic traits to determine if the environment was the source of the organisms associated with the disease. Clinical strains of V. cholerae were resistant to a greater number of drugs and exhibited multi-drug resistance compared with their environmental counterparts. Except for the presence of the genes for the El Tor haemolysin and the regulatory element ToxR in most of the strains of V. cholerae examined, non-O1, non-O139 V. cholerae strains lacked most of the other known virulence traits associated with toxigenic V. cholerae O1 or O139. Restriction fragment-length polymorphism of virulence-associated genes, ribotypes and DNA fingerprints of strains of matched serogroups showed considerable diversity, although some gene polymorphisms and ribotypes of a few strains of different serogroups were similar. It is concluded that despite sharing the same serogroup, environmental and clinical isolates were genetically heterogeneous and were of different lineages. 相似文献
2.
Tetracycline administration restores osteoblast structure and function during experimental diabetes. 总被引:2,自引:0,他引:2
Osteopenia is a recognized complication of diabetes mellitus in humans and experimental animals. We recently found that tetracyclines prevent osteopenia in the streptozotocin-induced diabetic rat and that this effect was associated with a restoration of defective osteoblast morphology (Golub et al., 1990). The present study extends these initial ultrastructural observations by assessing osteoblast function in the untreated and tetracycline-treated diabetic rats. After a 3-week protocol, non-diabetic control and diabetic rats, including those orally administered a tetracycline, minocycline (MC), or a non-antimicrobial tetracycline analog (CMT), were perfusion-fixed with an aldehyde mixture; the humeri were dissected and processed for ultracytochemical localization of alkaline phosphatase (ALPase) and Ca-ATPase activities. Some rats from each experimental group received an intravenous injection of 3H-proline as a radioprecursor of procollagen, and the humeri were processed for light microscopic autoradiography. In addition, the osteoid volume in each experimental group was quantitatively examined by morphometric analysis of electron micrographs. During the diabetic state, active cuboidal osteoblasts in the endosteum of control rats were replaced by flattened bone-lining cells that contained few cytoplasmic organelles for protein synthesis (Golgi-RER system), and active transport (mitochondria). Treating diabetic rats with MC, and even more so with CMT, appeared to "restore" osteoblast structure. During diabetes, bone-lining cells incorporated little 3H-proline or secreted little labeled protein and produced only a very thin osteoid layer. Tetracycline administration to the diabetics increased both the incorporation of 3H-proline by osteoblasts and their secretion of labeled protein toward the osteoid matrix, in a pattern similar to that seen in the non-diabetic controls.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Wilkie SE Newbold RJ Deery E Walker CE Stinton I Ramamurthy V Hurley JB Bhattacharya SS Warren MJ Hunt DM 《Human molecular genetics》2000,9(20):3065-3073
Three different mutations in codon 838 of GUCY2D, the gene for retinal guanylate cyclase 1, have been linked to autosomal dominant cone-rod dystrophy at the CORD6 locus. To examine the relationship between enzyme activity and disease severity, the three disease-causing substitutions (R838C, R838H and R838S) and four artificial mutations (R838A, R838E, R838L and R838K) were generated. Assay of GCAP1-stimulated cyclase activity in vitro shows that, compared with wild-type, R838E, R838L and R838K possess only low activity, whereas R838A, R838C, R838H and R838S have activity equal or superior to wild-type at low Ca(2+) concentrations. These four latter mutants showed a higher apparent affinity for GCAP1 than did wild-type. The Ca(2+) sensitivity of the GCAP1 activation was also altered with marked residual activity at high Ca(2+), the effect increasing: wild-type < R838C < R838H < R838A < R838S. Within the photoreceptor, this would result in a failure to inactivate cyclase activity at high physiological Ca(2+ )concentrations. Amongst the three disease-associated mutations, the effect correlates directly with disease severity. The wild-type and R838H mutant displayed a difference in pH sensitivity, with the mutant showing a higher specific activity with pH > 6.0. Site 838 is in the dimerization domain that forms a coiled-coil in the active protein. A computer-aided structure prediction of this region indicates that R838 in the wild-type breaks the structure at four helical turns, and there is an increasing tendency for the structure to continue for further turns in the order R838C < R838H,S,K < R838E < R838A < R838L. 相似文献
4.
A controlled trial of transcutaneous electrical nerve stimulation (TENS) and exercise for chronic low back pain 总被引:11,自引:0,他引:11
R A Deyo N E Walsh D C Martin L S Schoenfeld S Ramamurthy 《The New England journal of medicine》1990,322(23):1627-1634
A number of treatments are widely prescribed for chronic back pain, but few have been rigorously evaluated. We examined the effectiveness of transcutaneous electrical nerve stimulation (TENS), a program of stretching exercises, or a combination of both for low back pain. Patients with chronic low back pain (median duration, 4.1 years) were randomly assigned to receive daily treatment with TENS (n = 36), sham TENS (n = 36), TENS plus a program of exercises (n = 37), or sham TENS plus exercises (n = 36). After one month no clinically or statistically significant treatment effect of TENS was found on any of 11 indicators of outcome measuring pain, function, and back flexion; there was no interactive effect of TENS with exercise. Overall improvement in pain indicators was 47 percent with TENS and 42 percent with sham TENS (P not significant). The 95 percent confidence intervals for group differences excluded a major clinical benefit of TENS for most outcomes. By contrast, after one month patients in the exercise groups had significant improvement in self-rated pain scores, reduction in the frequency of pain, and greater levels of activity as compared with patients in the groups that did not exercise. The mean reported improvement in pain scores was 52 percent in the exercise groups and 37 percent in the nonexercise groups (P = 0.02). Two months after the active intervention, however, most patients had discontinued the exercises, and the initial improvements were gone. We conclude that for patients with chronic low back pain, treatment with TENS is no more effective than treatment with a placebo, and TENS adds no apparent benefit to that of exercise alone. 相似文献
5.
Alexander Rosewell Phil Shearman Sundar Ramamurthy Rob Akers 《Bulletin of the World Health Organization》2021,99(5):381
In the context of declining economic growth, now exacerbated by the coronavirus disease 2019 pandemic, Papua New Guinea is increasing the efficiency of its health systems to overcome difficulties in reaching global health and development targets. Before 2015, the national health information system was fragmented, underfunded, of limited utility and accessed infrequently by health authorities. We built an electronic system that integrated mobile technologies and geographic information system data sets of every house, village and health facility in the country. We piloted the system in 184 health facilities across five provinces between 2015 and 2016. By the end of 2020, the system’s mobile tablets were rolled out to 473 facilities in 13 provinces, while the online platform was available in health authorities of all 22 provinces, including church health services. Fractured data siloes of legacy health programmes have been integrated and a platform for civil registration systems established. We discuss how mobile technologies and geographic information systems have transformed health information systems in Papua New Guinea over the past 6 years by increasing the timeliness, completeness, quality, accessibility, flexibility, acceptability and utility of national health data. To achieve this transformation, we highlight the importance of considering the benefits of mobile tools and using rich geographic information systems data sets for health workers in primary care in addition to the needs of public health authorities. 相似文献
6.
The adaptive response is an error-free DNA repair mechanism induced by low levels of physical or chemical agents. Cells pre-exposed to such agents are resistant to genetic damage induced by subsequent treatment at a high dose. There are many reports on such adaptive responses. Recently we have shown the existence of adaptive responses in vivo in the grasshopper Poecilocerus pictus and the mouse and in vitro in human lymphocytes. Different enzymes are implicated in this DNA repair pathway. In an attempt to understand the molecular mechanism of the methyl methanesulfonate (MMS)-induced adaptive response, the present investigations have been undertaken employing nicotinamide, an inhibitor of the DNA repair enzyme poly(ADP-ribose) polymerase (PARP). Pre-, inter- and post-treatments with nicotinamide of MMS-treated mouse bone marrow cells were carried out. The results revealed that there is a significant reduction in the frequency of chromosomal aberrations compared with combined treatment, suggesting an enhancement of the adaptive response by nicotinamide. Further, the results of NAD+ assay in the inter-treatment experiment showed that there is no depletion of NAD+. Thus, it can be stated that PARP is not involved in the MMS-induced adaptive response in mouse bone marrow cells. 相似文献
7.
Lakshmi B Ramamurthy Ridhi Bhandari Savitha Kanakpur P Thejaswini 《Indian journal of ophthalmology》2022,70(3):1019
Purpose:To assess the outcome and response of transcutaneous retrobulbar injection of amphotericin B (TRAMB) in post-coronavirus disease of 2019 (COVID-19) rhino-orbito-cerebral mucormycosis (ROCM) and to establish a scoring system in guiding treatment modalities.Methods:An interventional, prospective study was done on 82 eyes of post-COVID-19 ROCM from May 2021 to July 2021. A comprehensive multi-departmental evaluation along with detailed ophthalmic examination, laboratory investigations, and radiological examination was done. Scoring points were given to each symptom, sign, and radiological features of orbit and the total score was taken. Based on these scores, severity of disease was grouped into A, B, and C corresponding to mild, moderate, and severe orbital ROCM. One milliliter of reconstituted liposomal amphotericin B was given to all patients every alternate day as three doses. Efficacy of these injections was assessed in all groups, even though other treatment modalities like orbital debridement and exenteration were considered for moderate and severe cases. Patients were followed up for a period of 8 weeks.Results:Out of 82 eyes, symptomatic improvement was seen in a major proportion (72%) of patients. A statistically significant improvement in scores was noted in group A (93% improved) with a P value of 0.002, while 68.4% showed improvement in group B (P-value- 0.0001). Group C with severe disease showed minimal improvement in post-injection scores of 41% (P-value 0.086), necessitating surgical intervention. No serious adverse effect of the drug or procedure was noted.Conclusion:Significant improvement in scores of groups A and B highlights TRAMB as an effective and safe treatment modality in mild to moderate ROCM. It is an effective adjunct in severe cases, along with other interventions. Also, the scoring system helps in assessing the severity and guiding in management strategies. 相似文献
8.
9.
Kishanchand Chethan Seetharam Prasad Lingadakai Ramachandra 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2012,23(3):e65-e66
Mucormycosis is a relatively uncommon, aggressive and lethal mycosis. Fungi from the order Mucorales are the etiological agents of mucormycosis. The condition is more common among the immunocompromised, diabetic patients with ketoacidosis and people with iron overload syndromes. Diagnosis of mucormycosis requires a high index of suspicion regarding the possibility of the condition in high-risk individuals. Timely diagnosis is critical to survival and minimization of morbidity. A favourable outcome is possible only if appropriate treatment is initiated as early as possible. The present article reports a case of ileocolic mucormycosis involving a patient with chronic renal failure and familial hyperuricemia. 相似文献
10.
Chethan Ramprasad Jane Yellowlees Douglas Baharak Moshiree 《Current Treatment Options in Gastroenterology》2018,16(4):489-510