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1.
Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa. 相似文献
2.
Shchelkanov MIu Kolobukhina LV Moskvina TM Aushev ID Kartoev AA Kelli EI Merkulova LN Grenkova EP Samokhvalov EI Petriaev VG Serobian AG Klimova EA Galkina IV Malyshev NA Aristova VA Slavskiĭ AA Luk'ianova NA Deriabin PG Gromashevskiĭ VL Efremenko VI Onishchenko GG L'vov DK 《Voprosy virusologii》2005,50(5):9-15
The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed. 相似文献
3.
Stanley G. Rane George G. Holz IV Kathleen Dunlap 《Pflügers Archiv : European journal of physiology》1987,409(4-5):361-366
Dihydropyridine (DHP) calcium channel antagonists, which inhibit the slowly inactivating or L-type cardiac calcium (Ca) current, have been shown to be ineffective in blocking45Ca influx and Ca-dependent secretion in a number of neuronal preparations. In the studies reported here, however, the antagonist DHP nifedipine inhibited both the L-type Ca current and potassium-evoked substance P (SP) release from embryonic chick dorsal root ganglion (DRG) neurons. These results suggest that, in DRG neurons. Ca entry through L-type channels is critical to the control of secretion. The inhibition of Ca current by nifedipine was both voltage and time-dependent, significant effects being observed only on currents evoked from relatively positive holding potentials maintained for several seconds. As expected from these results, nifedipine failed to inhibit L-type Ca current underlying the brief plateau phase of the action potential generated from the cell's normal resting potential; likewise, no significant effect of the drug was observed on action potential-stimulated SP release evoked by electrical field stimulation. The results of this work are discussed in terms of an assessment of the role of L-type Ca channels in neurosecretion.This work was supported by United States Public Health Service Grant NS16483 (KD) and by a USPHS Postdoctoral Fellowship (SGR) 相似文献
4.
James P. Thompson Richard B. Crandall Thomas J. Doyle IV Stephen A. Hines Catherine A. Crandall 《Parasitology research》1986,72(4):525-535
Eleven of 15 ferrets experimentally infected withBrugia malayi became amicrofilaremic after a brief patency; only four ferrets remained patent after 6 months of infection and two of these ferrets developed a high, persistent microfilaremia. Blastogenic responses of peripheral blood lymphocytes to antigens of microfilariae (mf), assayed in vitro, demonstrated an antigen sensitivity at prepatent, patent and postpatent periods of infection. Lymphocytes from ferrets with high microfilaremia had elevated background responses in culture which were directly correlated with the number of circulating mf. This background response was attributed to antigenic stimulation by mf present in the lymphocyte cultures; addition of mf to cultures of lymphocytes from postpatent ferrets induced responses equivalent to those observed in microfilaremic ferrets. Lymphocyte responses to the mitogen, concanavalin A, did not differ significantly among microfilaremic, amicrofilaremic and uninfected ferrets. Antibody in IgG to antigens of mf measured by ELISA and by immunoblots from SDS-PAGE showed similar patterns of response in ferrets which became amicrofilaremic and in the few ferrets which remained microfilaremic. Prausnitz-Kustner tests demonstrated no consistent differences in titers to microfilarial antigens between patent and amicrofilaremic ferrets. The results suggest a high level of immune responsiveness to antigens of mf in infected ferrets with no evidence of immunosuppression associated with prolonged microfilaremia or of major changes in immune responses with development of amicrofilaremic infections. 相似文献
5.
Magnitude of the inflammatory response to cardiopulmonary bypass and its relation to adverse clinical outcomes 总被引:12,自引:0,他引:12
J. H. Holmes IV N. C. Connolly D. L. Paull M. E. Hill S. W. Guyton S. F. Ziegler R. A. Hall 《Inflammation research》2002,51(12):579-586
INTRODUCTION: Cardiopulmonary bypass (CPB) induces an inflammatory response believed to contribute to postoperative morbidity. We hypothesized that the magnitude of the inflammatory response following CPB would be associated with adverse clinical outcomes. METHODS: Twenty-nine patients had plasma TNF, IL-6, IL-8, elastase, histamine, complement C5a, and complement C3a measured by ELISA before, during, and after cardiac operations employing CPB. Inflammatory mediator levels were analyzed with respect to outcomes. RESULTS: Mediator levels peaked at 4 h post-CPB and either returned to baseline or substantially decreased by 24 h. Patients with peak mediator levels above the median for the group as a whole were classified as 'hyper-responders'; those with levels below the median were classified as 'normal responders'. While IL-8, C3a, and IL-6 levels were independently associated with adverse outcomes, TNF, histamine, and C5a levels were not. Elastase levels trended towards adverse outcomes. IL-8 'hyper-responders' experienced significantly greater postoperative weight gain and had higher IL-8 levels at 24 h (p<0.05), with trends towards renal impairment and protracted supplemental oxygen requirements. C3a 'hyper-responders' strongly trended towards increased bleeding, delayed extubation, greater postoperative weight gain, and decreased levels of independent functioning at discharge (p < or = 0.10). IL-6 'hyper-responders' experienced significantly more postoperative bleeding, delayed extubation, and higher IL-6 levels at 24 h compared to 'normal responders' (p < 0.05). They strongly trended towards greater postoperative weight gain and decreased levels of independent functioning at discharge (p < or = 0.10). CONCLUSIONS: Patients who have an exaggerated inflammatory response to CPB tend to bleed more, require more respiratory support, demonstrate greater capillary leak via weight gain, and display a decline in independent functioning relative to normal responders. Thus, it appears that the magnitude of the inflammatory response to CPB adversely influences clinical outcomes. 相似文献
6.
Merrill S. Kies David Grinblatt Melissa Runge-Morris Richard Blough Arletrice Watkins Sam Taylor IV 《Investigational new drugs》1994,12(1):45-47
The Illinois Cancer Center entered 25 patients on a phase II trial of intravenous melphalan treating patients with recurrent, metastatic or locally advanced and inoperable squamous cell carcinoma of the head and neck. All patients had bi-dimensionally measurable disease, at least a sixty day life expectancy, and adequate performance status (ECOG scale 2). All patients except one had received prior radiotherapy, chemotherapy or both. Melphalan dosage was 30 mg/m2 every three weeks. Twenty-four patients were evaluable for response. One patient with laryngeal carcinoma had a clinical complete response of a nodal metastasis. Four patients had stabilization of disease for one to three months. There was formidable toxicity, including neutropenia (ANC < 1000/l 36%), and thrombocytopenia (< 50,000/l 32%). There were no drug-related deaths. Melphalan administered intravenously does not appear to be efficacious therapy in patients with previously treated advanced head and neck squamous carcinomas. 相似文献
7.
Identification of amino-terminal sequences contributing to tryptophan hydroxylase tetramer formation
Tryptophan hydroxylase (TPH) catalyzes the rate-limiting step in the biosynthesis of serotonin. In the rabbit, TPH exists
as a tetramer of four identical 51-kDa subunits comprised of 444 amino acids each. The enzyme consists of an amino-terminal
regulatory domain and a carboxyl-terminal catalytic domain. Previous studies demonstrated that within the carboxyl-terminus
of TPH, there resides an intersubunit binding domain (a leucine zipper) that is essential for tetramer formation. However,
it is hypothesized that a 4,3-hydrophobic repeat identified within the regulatory domain of TPH (residues 21–41) may also
be involved in macromolecular assembly. To test this hypothesis, a series of amino-terminal deletions (NΔ15, 30, 41, and 90)
were created and assessed for macromolecular structure using size-exclusion chromatography. The amino-terminal deletion NΔ15,
upstream from the 4,3-hydrophobic repeat, was capable of forming tetramers. However, when a portion of the 4,3-hydrophobic
repeat was deleted (NΔ30), a heterogeneous elution pattern of tetramers, dimers, and monomers was observed. Complete removal
of the 4,3-hydrophobic repeat (NΔ41) rendered the enzyme incapable of forming tetramers; a monomeric form predominated. In
addition, a double-point mutation (V28R-L31R) was created in the hydrophobic region of the enzyme. The introduction of two
arginines (R) at positions 28 and 31 respectively, in the helix disrupted the native tetrameric state of TPH. According to
size-exclusion chromatography analysis, the double-point mutant (V28R-L31R) formed dimers of 127 kDa. Thus, it is concluded
that there is information within the amino-terminus that is necessary for tetramer formation of TPH. This additional intersubunit
binding domain in the amino-terminus is similar to that found in the carboxyl-terminus. 相似文献
8.
Daniel R Christie Faheem M Shaikh John A Lucas IV John A Lucas III Susan L Bellis 《Journal of ovarian research》2008,1(1):1-8
Background
Ovarian adenocarcinoma is not generally discovered in patients until there has been widespread intraperitoneal dissemination, which is why ovarian cancer is the deadliest gynecologic malignancy. Though incompletely understood, the mechanism of peritoneal metastasis relies on primary tumor cells being able to detach themselves from the tumor, escape normal apoptotic pathways while free floating, and adhere to, and eventually invade through, the peritoneal surface. Our laboratory has previously shown that the Golgi glycosyltransferase, ST6Gal-I, mediates the hypersialylation of β1 integrins in colon adenocarcinoma, which leads to a more metastatic tumor cell phenotype. Interestingly, ST6Gal-I mRNA is known to be upregulated in metastatic ovarian cancer, therefore the goal of the present study was to determine whether ST6Gal-I confers a similarly aggressive phenotype to ovarian tumor cells.Methods
Three ovarian carcinoma cell lines were screened for ST6Gal-I expression, and two of these, PA-1 and SKOV3, were found to produce ST6Gal-I protein. The third cell line, OV4, lacked endogenous ST6Gal-I. In order to understand the effects of ST6Gal-I on cell behavior, OV4 cells were stably-transduced with ST6Gal-I using a lentiviral vector, and integrin-mediated responses were compared in parental and ST6Gal-I-expressing cells.Results
Forced expression of ST6Gal-I in OV4 cells, resulting in sialylation of β1 integrins, induced greater cell adhesion to, and migration toward, collagen I. Similarly, ST6Gal-I expressing cells were more invasive through Matrigel.Conclusion
ST6Gal-I mediated sialylation of β1 integrins in ovarian cancer cells may contribute to peritoneal metastasis by altering tumor cell adhesion and migration through extracellular matrix. 相似文献9.
Xiang Li Chun-Hao Huang Francisco J. Snchez-Rivera Margaret C. Kennedy Darjus F. Tschaharganeh John P. Morris IV Antonella Montinaro Kevin P. O'Rourke Ana Banito John E. Wilkinson Chi-Chao Chen Yu-Jui Ho Lukas E. Dow Sha Tian Wei Luan Elisa de Stanchina Tinghu Zhang Nathanael S. Gray Henning Walczak Scott W. Lowe 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(17)
10.