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61.
Lyons ET Delong RL Nadler SA Laake JL Orr AJ Delong BL Pagan C 《Parasitology research》2011,109(3):581-589
The peritoneal cavity (PNC) and intestine of northern fur seal (Callorhinus ursinus) pups and California sea lion (Zalophus californianus) pups that died in late July and early August, 2003, on San Miguel Island, California, were examined for hookworms. Prevalence
and morphometric studies were done with the hookworms in addition to molecular characterization. Based on this and previous
molecular studies, hookworms from fur seals are designated as Uncinaria lucasi and the species from sea lions as Uncinaria species A. Adult hookworms were found in the PNC of 35 of 57 (61.4%) fur seal pups and of 13 of 104 (12.5%) sea lion pups.
The number of hookworms located in the PNC ranged from 1 to 33 (median = 3) for the infected fur seal pups and 1 to 16 (median = 2)
for the infected sea lion pups. In addition to the PNC, intestines of 43 fur seal and 32 sea lion pups were examined. All
of these pups were positive for adult hookworms. The worms were counted from all but one of the sea lion pups. Numbers of
these parasites in the intestine varied from 3 to 2,344 (median = 931) for the fur seal pups and 39 to 2,766 (median = 643)
for the sea lion pups. Sea lion pups with peritoneal infections had higher intensity infections in the intestines than did
pups without peritoneal infections, lending some support for the hypothesis that peritoneal infections result from high-intensity
infections of adult worms. There was no difference in intestinal infection intensities between fur seal pups with and without
peritoneal infections. Female adult hookworms in the intestines of both host species were significantly larger than males,
and sea lion hookworms were larger than those in fur seals. Worms in the intestine also were larger than worms found in the
PNC. Gene sequencing and (RFLP) analysis of (PCR) amplified (ITS) ribosomal DNA were used to diagnose the species of 172 hookworms
recovered from the PNC and intestine of 18 C. ursinus and seven Z. californianus hosts. These molecular data revealed that U. lucasi (hookworm of C. ursinus) and Uncinaria species A (of Z. californianus) infrequently mature in the intestine of the opposite host species in California rookeries. However, there is no support
from molecular data for the hypothesis that cross-infection with “the wrong” Uncinaria species is a contributing factor in these cases of host peritonitis. The major significance of this research is the unusual
finding of adult hookworms in the PNC of so many dead pups. No obvious explanation for this occurrence could be determined.
Further research, like in the present study, should help understand and monitor the apparent ever changing role of hookworm
disease in the health of northern fur seal and California sea lion pups on SMI. 相似文献
62.
Ectodermal dysplasias (EDs) are a group of developmental disorders (more than 100) mainly affecting ectodermal tissues and organs. The X-linked hypohidrotic ED (HED) is the most common form of EDs, involving defects in teeth, sweat glands, and hair. In a few reports, HED has been associated with reduced salivary function. In the present case report, a dramatically reduced salivary fluid and acidic proline rich protein production was identified in a 38-year-old man with HED. Computed tomography was performed, revealing that one submandibular gland and both parotid glands were hypoplastic, whereas the right submandibular gland seemed to be absent. These findings are in line with a general developmental disturbance also involving the salivary glands. As salivary tests are inexpensive and easy to perform, it is suggested to routinely evaluate salivary secretion in persons with HED, to prevent a possible negative impact on oral health. 相似文献
63.
Oyen RH; Gielen JL; Van Poppel HP; Verbeken EK; Van Damme BJ; Baert LV; Baert AL 《Radiology》1988,169(3):705-707
Abdominal radiography, excretory urography, retrograde pyelography, and computed tomography were performed in two patients who had undergone retrograde pyelography with thorium dioxide (Thorotrast) approximately 40 years ago. Both patients developed a transitional cell carcinoma due to suburothelial thorium deposition. Typical thorium densities were demonstrated at CT in the peripelvicalyceal area as well as in retroperitoneal lymph nodes. Elderly patients in whom radiographic examination reveals retained Thorotrast in the kidney should be followed up because of the high risk of renal carcinoma. 相似文献
64.
Eleanor Race Mackey Alexandra Olson Stephanie Merwin Jichuan Wang Evan P. Nadler 《Obesity surgery》2018,28(2):421-426
Objectives
Bariatric surgery is an effective treatment for youth with severe obesity. However, outcomes are variable and there remains sparse understanding of predictors of weight loss following surgery. The current study examines the role of adolescent-reported pre-operative social support around exercise, binge eating, and exercise to predict excess body mass index (EBMI) loss from 3 to 12 months post-surgery.Method
Participants were 101 adolescents ages 12–21 (M age = 16.6, SD = 1.8). Pre-operative body mass index (BMI) ranged from 35 to 87 (M = 50.3, SD = 8.6). Structural equation modeling (SEM) was used to evaluate a model of the association of adolescent report of perceived social support for exercise with less binge eating (items from the Eating Disorder Diagnostic Scale) and more self-reported exercise (items from the Youth Risk Behavior Surveillance System). The model was used to predict EBMI loss at 3, 6, 9, and 12 months post-surgery.Results
Social support significantly predicted exercise and demonstrated a trend for predicting binge eating, such that more social support was associated with more exercise and a trend for less binge eating. Binge eating was associated with less EBMI loss. However, there was no association of exercise with EBMI loss.Conclusions
Pre-operative binge eating should be a target for identification and treatment prior to sleeve gastrectomy in adolescents. Although not directly or indirectly associated with EBMI loss, perceived social support around exercise was associated with increased exercise, which may make it a consideration for a target for intervention as well.65.
Yang Z Chen M Deng S Ellett JD Wu R Langman L Carter JD Fialkow LB Markmann J Nadler JL Brayman K 《Transplantation proceedings》2004,36(5):1532-1533
Pancreatic islet transplantation can replace functional insulin-secreting beta cells for patients with type 1 diabetes. More than 300 patients who have received islet transplantation have returned to a euglycemic condition without using insulin. Therefore, islet transplantation has gained public attention and interest. Unfortunately, shortages in organ donations, suboptional antirejection regimens, and difficulties in islet isolation limit clinical utilization of this therapy. Recently, successful islet transplantation has been reported using a centralized islet isolation facility. The advantage of this experience is that it avoids the high costs in building an isolation facility and maintaining an experienced technical team. However, a private airplane carrier was required for transporting islets back to the transplantation site in a remote hospital. The cost of this specialized transportation was still too high to be considered as a routine procedure. In this study, we report our experience using commercial carriers to deliver isolated human islets from an established isolation facility to a remote medical center. 相似文献
66.
Taxol, a microtubule stabilizing agent, blocks the replication of Trypanosoma cruzi. 总被引:4,自引:4,他引:4
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S G Baum M Wittner J P Nadler S B Horwitz J E Dennis P B Schiff H B Tanowitz 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(7):4571-4575
Taxol, an experimental antitumor agent and stabilizer of microtubules, inhibits in vitro replication of the human pathogenic hemoflagellate Trypanosoma cruzi. Micromolar concentrations of the drug prevent the completion of cell division in these organisms but allow the multiplication of cell organelles such as the nucleus, kinetoplast, and flagellum. The result is the formation of motile organisms that have extra organelles but cannot fully replicate. Division proceeds to a relatively fixed locus on the long axis of the organism, suggesting the presence of a specific affected structure or function at this site. It is postulated that taxol produces these effects by stabilizing a portion of the microtubular cytoskeleton of T. cruzi. 相似文献
67.
P Stashenko L M Nadler R Hardy S F Schlossman 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(6):3848-3852
The fate of two recently described human B lymphocyte-specific antigens (B1 and B2) was studied after B-cell activation in vivo and in vitro. Whereas both B1 and B2 were present on virtually all B cells from normal lymph nodes, B2 was absent from approximately 50% of B cells from hyperplastic lymph nodes. When B cells from spleen, tonsil, or peripheral blood were stimulated in vitro with pokeweed mitogen, activated cells were found to lose B2 (days 4-5) and subsequently B1 (days 6-7). Temporally, B2 loss was accompanied by loss of surface IgD, expression of T10, and the development of intracytoplasmic IgM; B1 loss was correlated with the acquisition of surface IgG and the appearance of intracytoplasmic IgG. Peripheral blood B cells, on which B2 is normally only weakly expressed (B1++++B2+) in contrast to B cells from secondary lymphoid organs (B1++++B2++), exhibited a transitory increase in B2 expression to the B1++++B2++ phenotype prior to B2 disappearance during activation. Taken together with other findings, this observation suggests that peripheral blood may contain a relatively immature subpopulation of B cells. 相似文献
68.
D C Roy R Tantravahi C Murray K Dear B Gorgone K C Anderson A S Freedman L M Nadler J Ritz 《Blood》1990,75(1):296-304
Mixed hematopoietic chimerism (MC) is a common finding after allogeneic bone marrow transplantation (BMT), but the natural history of this phenomenon remains unclear. To understand the evolution and the implications of this finding, we performed a prospective analysis of the development of mixed chimerism in 43 patients with hematologic malignancies who received bone marrow (BM) from human leukocyte antigen (HLA)-identical sibling donors. T-cell depletion in vitro with anti-T12 (CD6) monoclonal antibody and rabbit complement was used as the only method of graft-versus-host disease (GVHD) prophylaxis. Overall, MC was identified in peripheral blood (PB) and BM in 22 of 43 (51%) patients evaluated. MC was found by restriction fragment length polymorphism (RFLP) analysis in 21 of 40 (53%) patients, by cytogenetic analysis in 6 of 29 (21%) patients, and by red blood cell phenotyping in 4 of 9 (44%) patients. RFLP studies were performed at 0.5, 1, 3, 6, 9, and 12 months post-BMT and then every 6 months, and showed a high probability of developing MC in the first 6 months after BMT followed by stabilization after 12 months. Cytogenetic analysis was less sensitive in detecting MC. Once MC was detected after BMT, the percentage of recipient cells increased very slowly over more than 3 years of follow-up, and no patient reverted to complete donor hematopoiesis (CDH). Thus, recipient and donor cells remained in a relative state of equilibrium for prolonged periods that seemed to favor recipient cells over donor cells. Patient's disease, remission status, or intensity of the transplant preparative regimen did not influence the subsequent development of mixed chimerism. Early immunologic reconstitution was the only factor that correlated with the subsequent chimeric status of the patients. The percentage and absolute number of T3 (CD3) and T4 (CD4) positive cells at day 14 after BMT were significantly higher in the patients who maintained CDH but NK cell reconstitution was similar in both groups, suggesting that early reconstitution with T cells may play a role in preventing recovery of recipient cells after BMT. GVHD was also associated with maintenance of CDH, but the probability of relapse, survival, and disease-free survival was identical in patients with MC and CDH. 相似文献
69.
Association between clonogenic cell growth and clinical risk group in B-cell chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
Chronic lymphocytic leukemia of B-cell origin (B-CLL) is a disease with a variable clinical course, despite the fact that the neoplastic cells in this disorder are homogeneous with respect to morphology, immunophenotype, and cell cycle stage. To further investigate the heterogeneity observed in the clinical behavior of B-CLL, we determined the phenotype and growth requirements of clonogenic cells from 28 patients with B-CLL from low-, intermediate-, and high-risk groups as defined by the Rai staging system. Using methyl-cellulose as a semi-solid media with feeder cells and/or growth factors, colonies were observed with one or more of the culture conditions tested in 25 of 28 CLLs. Phenotypic analysis of colonies demonstrated that the clonogenic cells uniformly expressed la, CD19, CD20, CD5, and the identical light chain as the original CLL cell cultured. However, heterogeneity was observed in clonogenic B-CLL cell growth among the three different CLL risk groups. Clonogenic cells from patients with low-risk CLL required either irradiated unstimulated T cells, with or without conditioned media (CM) or irradiated activated T cells alone for colony formation. Both the number of colonies (227 +/- 15) as well as the number of cells per colony (220 +/- 82) were large, with a mean cloning efficiency of 0.39%. In contrast, clonogenic cells from patients with intermediate- and high-risk CLL required the combination of both irradiated activated T cells and CM. As compared with the low-risk CLLs, both the number and size of the colonies formed by the intermediate- (74 +/- 17, 70 +/- 39) and high- (83 +/- 28, 40 +/- 14) risk groups were significantly lower (P less than .0001). Similarly, the mean cloning efficiency was significantly reduced to 0.15% and 0.14%, respectively. None of the recombinant cytokines (interleukin 1 [IL-1] to IL-7, tumor necrosis factor, alpha and gamma-interferon, B-cell growth factor, and granulocyte macrophage colony-stimulating factor) alone or in combination with each other could entirely replace the stimulatory effect of the activated T cells. These data suggest that clinical progression of B-CLL is associated with a loss of clonogenic potential in the circulating pool of neoplastic cells, which require as yet undefined factors provided by activated T cells and CM. 相似文献
70.
Key role of diacylglycerol-mediated 12-lipoxygenase product formation in angiotensin II-induced aldosterone synthesis 总被引:2,自引:0,他引:2
We have shown earlier that the 12-lipoxygenase product of arachidonic acid (AA), 12-hydroxyeicosatetraenoic acid (12-HETE), plays an important role in mediating angiotensin II (AII)-induced aldosterone secretion (J. Clin. Invest. (1987) 80, 1763). In the present study, we have evaluated whether diacylglycerol (DG) is the source of arachidonic acid giving rise to this 12-HETE. Treatment of rat adrenal glomerulosa cells with a DG lipase inhibitor, RHC 80267, which prevents conversion of DG to AA and HETEs, blocked AII-induced aldosterone and 12-HETE formation. In contrast, a DG kinase inhibitor, R59022, which prevents conversion of DG to phosphatidic acid, potentiated AII-induced aldosterone and 12-HETE formation. These two inhibitors block DG metabolism which would be expected to lead to increased DG levels and protein kinase C activity and AII-induced steroidogenesis. However, only R59022 potentiated AII action while RHC 80267 was inhibitory. This suggests that conversion of DG to AA and 12-HETE is important for AII action. Further proof for this was obtained by measuring [3H]AA-labeled DG levels. The combination of the inhibitors significantly potentiated AII-induced DG formation even though this same combination was inhibitory on AII-induced aldosterone and 12-HETE. Thus, the inhibitory effect of RHC 80267 is due to blockade of AA release and not of DG formation. These results suggest that DG plays a dual role in AII action, both as an activator of protein kinase C and as a source of AA for 12-HETE formation. 相似文献