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1.
Although there were essential achievements in understanding the pathogenesis of rheumatoid arthritis (RA), the mentioned pathologies still remain one of the most complicated problems in practical medicine. Rheumatologists arrived, during the last decade, at a conclusion on a need in an early aggressive therapy, because the destructive changes develop in joints yet during the first 4 months starting from the onset of initial RA clinical signs. The approach towards treatment by non-steroid anti-inflammatory drugs changed with respect to the risk factors related with the onset of potential complications and to choosing the safest drugs, which became possible owing to the development of drugs, whose action is aimed at suppression of cyclo-oxygenase-2 (COG-2). The group of "disease-modifying antirheumatic drugs" (DMARD) was added two new cytotoxic drugs, i.e. cyclosporin A and leflunomid. A concept of combined therapy by 2 or 3 DMARD was elaborated to ensure an effect in case of tolerance to monotherapy. The feasibility and safety of therapy by glucocorticosteroids both with small daily doses and with pulse therapy in extra aggressive RA variations were proven. The use of biological agents, i.e. of monoclonal antibodies to TNF alpha and IL-4 or of their receptors antagonists, is an absolutely new trend in RA treatment. Treatment safety is in the focus of attention; monitoring methods were designed to ensure such safety.  相似文献   
2.
High incidence rates of isoniazid-, rifampin-, and multiple-drug-resistant tuberculosis have been reported in countries of the former Soviet Union (FSU). Genotypic (unlike phenotypic) drug resistance assays do not require viable cultures but require accurate knowledge of both the target gene and the mutations associated with resistance. For these assays to be clinically useful, they must be able to detect the range of mutations seen in isolates from the population of tuberculosis patients to which they are applied. Two novel macroarrays were applied to detect mutations associated with rifampin (rpoB) and isoniazid (katG and inhA) resistance. In a sample of 233 isolates from patients in Samara, central Russia, 46.5% of isolates possessed mutations in both the rpoB and the katG (or inhA) genes. Combined results from the macroarrays demonstrated concordance in 95.4 and 90.4% of phenotypically defined rifampin- and isoniazid-resistant isolates, respectively. The contribution of different mutations to resistance was comparable to that reported previously for non-FSU countries, with 90% of rifampin-resistant isolates and 93% of isoniazid resistant isolates due to rpoB531 and katG315 mutations, respectively. The percentage of phenotypically resistant rifampin isolates with no mutations in the rpoB codons 509 to 536 was 4.2%, which was similar to previous reports. Novel macroarrays offer a rapid, accurate, and relatively cheap system for the identification of rifampin-, isoniazid-, and multiple-drug-resistant Mycobacterium tuberculosis isolates.  相似文献   
3.
Testicular seminoma is characterized by a prominent lymphoid infiltrate and an excellent prognosis. Cytotoxic T-lymphocytes (CTLs) infiltrating seminoma tumour nests constitute a major subset of the lymphoid infiltrate. The objective of this study was to determine whether CTLs express markers of cytotoxic potential and activity and whether the number of activated CTLs correlates with the extent of apoptosis in testicular seminomas, as opposed to non-seminomatous testicular germ cell tumours (NSTGCTs). Twenty cases of pure seminoma as well as 20 cases of NSTGCTs including 16 mixed germ cell tumours (MGCTs) were studied. Immunohistochemistry for the cytotoxic markers TIA-1 (cytotoxic potential) and granzyme B (cytotoxic activity) and the T-cell markers CD3 and CD8 was performed on formalin-fixed, paraffin-embedded sections. The apoptotic index (AI) was determined by the TUNEL method. The number of CD3(+), CD8(+), TIA-1(+), and granzyme B(+) cells in tumour cell nests was markedly increased in testicular seminomas, compared with NSTGCTs (p<0.01). Activated granzyme B(+) cells numbered 25.6+/-5.2 per high power field in seminomas and 8.9+/-3.2, 8.1+/-3.9, and 0.4+/-0.2 for embryonal carcinomas, yolk sac tumours, and immature teratomas, respectively. Double immunohistochemical staining for granzyme B and CD8 revealed that 82.6+/-8.5% of granzyme B-expressing cells were CD8(+). The tumour cell AI was significantly increased in embryonal carcinoma, compared with the seminoma, yolk sac tumour, and immature teratoma subgroups (6.7+/-1.3, 2.3+/-0.3, 3.0+/-1.1, and 2.3+/-1.1, respectively, p<0.001). TUNEL/CD3 double immunostaining revealed that a significant proportion of the apoptotic seminomatous tumour cells were in direct contact with one or more CD3(+) lymphocytes (47.2+/-6.2%). The number of activated granzyme B(+) CTLs showed a strong linear correlation with the AI in the seminoma group (r=0.71, p<0.0001) but not in other subgroups. TUNEL/granzyme B double immunolabelling revealed that a proportion of activated granzyme B(+) lymphocytes (20%) were often seen in close contact with apoptotic tumour cells. The presence of increased numbers of activated cytotoxic lymphocytes in testicular seminomas suggests that apoptotic tumour cell death in this neoplasm may be triggered by cytotoxic granule effectors. This phenomenon may be one of the key host immune mechanisms leading to the excellent prognosis in this tumour.  相似文献   
4.
The gammacoronavirus avian infectious bronchitis virus (IBV) is a highly contagious respiratory pathogen of primary economic importance to the global poultry industry. Two IBV lineages (GI-11 and GI-16) have been widely circulating for decades in South America. GI-11 is endemic to South America, and the GI-16 is globally distributed. We obtained full-length IBV genomes from Argentine and Uruguayan farms using Illumina sequencing. Genomes of the GI-11 and GI-16 lineages from Argentina and Uruguay differ in part of the spike coding region. The remaining genome regions are similar to the Chinese and Italian strains of the GI-16 lineage that emerged in Asia or Europe in the 1970s. Our findings support that the indigenous GI-11 strains recombine extensively with the invasive GI-16 strains. During the recombination process, GI-11 acquired most of the sequences of the GI-16, retaining the original S1 sequence. GI-11 strains with recombinant genomes are circulating forms that underwent further local evolution. The current IBV scenario in South America includes the GI-16 lineage, recombinant GI-11 strains sharing high similarity with GI-16 outside S1, and Brazilian GI-11 strains with a divergent genomic background. There is also sporadic recombinant in the GI-11 and GI-16 lineages among vaccine and field strains. Our findings exemplified the ability of IBV to generate emergent lineage by using the S gene in different genomic backgrounds. This unique example of recombinational microevolution underscores the genomic plasticity of IBV in South America.  相似文献   
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6.
The treatment of choice for Stenotrophomonas maltophilia is trimethoprim-sulfamethoxazole (SXT). Fluoroquinolones (FQs) have in vitro activity against S. maltophilia; however, there is limited published information on their effectiveness. The purpose of this study is to compare the effectiveness of FQs and SXT for the treatment of S. maltophilia. A retrospective review of 98 patients with S. maltophilia infections who received SXT or FQ monotherapy was conducted. Patients ≥18 years old with a positive culture for S. maltophilia and clinical signs of infection who received treatment for ≥48 h were included. Microbiological cure and clinical response were evaluated at the end of therapy (EOT). In-hospital mortality and isolation of nonsusceptible isolates were also evaluated. Thirty-five patients received SXT, and 63 patients received FQ; 48 patients received levofloxacin, and 15 patients received ciprofloxacin. The most common infection was pulmonary. The overall microbiological cure rate at EOT was 63%. Thirteen of 20 patients (65%) who received SXT and 23 of 37 patients (62%) who received FQ had microbiological cure at EOT (P = 0.832). The overall clinical success rate was 55%, 52% for those who received FQ and 61% for those who received SXT (P = 0.451). In-hospital mortality was 24%, with similar rates in the two groups (25% for FQ versus 22% for SXT; P = 0.546). Development of resistance on repeat culture was 30% for FQ and 20% for SXT (P = 0.426). Fluoroquinolone and SXT monotherapies may be equally effective for the treatment of S. maltophilia infections. Resistance was documented in subsequent isolates of S. maltophilia in both groups.  相似文献   
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8.
Case We describe a second case of fluconazole associated agranulocytosis with thrombocytopenia and recovery upon discontinuation of therapy. The patient began to have changes in white blood cells and platelets within 48 h of administration of fluconazole and began to recover with 48 h of discontinuation. This case highlights that drug-induced blood dyscrasias can occur unexpectedly as a result of treatment with a commonly used drug thought to be “safe”. Conclusion According to Naranjo’s algorithm the likelihood that our patient’s agranulocytosis and thrombocytopenia occurred as a result of therapy with fluconazole is probable, with a total of six points. We feel that the weight of the overall evidence of this evidence is strong. In particular the temporal relationship of bone marrow suppression to the initiation of fluconazole and the abatement of symptoms that rapidly reversed immediately following discontinuation.  相似文献   
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10.
Donor‐specific anti‐HLA antibodies (DSA) causing CAMR are responsible for a high proportion of long‐term graft failures after RTX. We studied the prevalence of DSA in RTX children biopsied for creeping Cr, its relationship with NA, and patient and graft survival according to histopathology. Between 2008 and 2013, 92 children were biopsied at a median of 38 months post‐RTX. At biopsy, the prevalence of DSA was 49% and C4d 70%. NA rate was 45%, higher in adolescents (60%). Most frequent diagnoses were CAMR (72%) and interstitial fibrosis with tubular atrophy (IFTA) (28%). Forty‐five of 66 patients with CAMR (68%) had detectable DSA. Twenty‐one DSA‐negative patients with CAMR had histological damage (IFTA + C4d positivity). C4d was detected in 64 of 66 biopsies with CAMR. Recipients with IFTA alone had neither C4d, nor detectable DSA, and were adherent. Graft survival at five yr was 89% in patients with CAMR, 79% in those with CAMR + TCMR Banff I, 33% in those with CAMR + TCMR Banff II, and 96% in those with IFTA. ABMR and complement activation were frequent in children biopsied for creeping Cr. Recipients with DSA were more likely to be non‐adherent and have CAMR or CAMR + TCMR and worse graft survival.  相似文献   
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