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排序方式: 共有590条查询结果,搜索用时 62 毫秒
1.
Acute appendicitis: CT and US correlation in 100 patients 总被引:19,自引:1,他引:18
2.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
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A L Ney P H Kelly D T Tsukayama M P Bubrick 《The Journal of trauma》1990,30(8):1000-5; discussion 1005-6
The following study was done to assess whether fibrin glue-antibiotic suspension (FGAS) can prevent infection of a PTFE vascular graft in a contaminated wound. METHODS: FGAS was made by combining cryoprecipitate with a mixture of bovine thrombin, aminocaproic acid, and tobramycin (5 mg/cc thrombus). Antibiotic activity was documented by in vitro kinetics which revealed initial elutions to be greater than 8,000 mu gm/cc and elutions at 4 days to be greater than 2 mcg/cc. Twelve dogs had a 1-cm section of infrarenal aorta replaced with a PTFE graft that had been bathed in a 2-cc solution of E. coli 3 x 10(8) CFU/ml and S. aureus 3 x 10(8) CFU/ml. Both organisms were sensitive to tobramycin and cefonicid. Dogs were divided into three groups of four. Group I had a contaminated PTFE graft placed and no further therapy. Group II had a contaminated PTFE graft placed and sealed with fibrin glue. Group III had a contaminated PTFE graft placed and sealed with FGAS. All three groups received daily IV cefonicid. RESULTS: Group I: Four of four dogs were reoperated on the fourth day for suspected sepsis and all four had pseudoaneurysms (one ruptured). Three of four were culture positive for S. aureus and two of four positive for E. coli. Group II: Four of four died of anastomotic disruption by the third day. Four of four were culture positive for S. aureus and E. coli. Group III: All four dogs survived and were sacrificed on Day 17: all anastomoses were normal. Animal survival was significantly associated with the treatment given (p = 0.0025). Three of four tissue cultures of the grafts were weakly positive for S. aureus and one of four for E. coli and Pseudomonas. Serum tobramycin levels were negligible at 12, 24, 72, and 96 hours. CONCLUSIONS: The data show that FGAS was associated with a reduction in vascular graft infection and pseudoaneurysm formation after exposure to a standardized bacterial inoculum. Whether complete eradication of all organisms can be achieved with higher doses of tobramycin is as yet undetermined. 相似文献
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Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献
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