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This study characterizes by serological and molecular methods the HLA class I and class II alleles in a group of celiac disease children, their parents and a control group of Sardinian descent. We found the DR3-DQw2 haplotype in all patients which was, in almost all cases (84%), associated with the HLA-A30, B18, DR3, DRw52, DQw2 extended haplotype named "Sardinian haplotype" because of its frequency (12-15%) in this Caucasian population. This is the first time that this DQw2-linked haplotype has been reported with such a high frequency in CD. However, no different distribution of "Sardinian haplotype" was found comparing CD patients with 91 haplotyped DQw2-positive controls. This finding indicates that the DQw2 antigen in Sardinians is almost always associated with the A30, B18, DR3, DRw52, DQw2 extended haplotype. The DQA1 and DQB1 second exon sequence analysis of the B18,DR3 and B8,DR3 haplotypes showed the DQA1*0501 and DQB1*0201 alleles which shared the already published sequences. DPB1 subtyping showed the DPB1*0301 allele more frequently (p less than 0.005) in CD patients but this difference was no longer significant when patients and controls, both heterozygous for the DR3-DQw2 haplotype, were compared. We suggest that the divergent HLA extended haplotypes and DP allele associated with CD, described in different Caucasian populations, can be explained by the particular DQw2 linkage disequilibrium in each population.  相似文献   
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Objectives In this case-control study we tested the hypothesis of an association between some psychosomatic skin diseases, attachment style and stress. Patients and methods A total of 177 cases and 194 controls seen between November 1992 and November 1993 at the Istituto Dermopatico dell'lmmacolata (IDD) in Rome, were enrolled into the study. Cases were outpatients with first diagnosis of hyperidrosis, chronic urticaria, generalized pruritus or alopecia areata. Controls were outpatients seen in the same period of time with first diagnosis of pigmenled nevi, keratosis or mycosis. The presence and weight of life stress events were assessed by u standard precoded questionnaire based on the Schedule of Recent Experiences (SRE) and on the Life Experiences Survey (LES). The attachment style was assessed by a modified version of the Shaver and Hazan questionnaire about feelings in a love relationship. We calculated 3 scores for each individual and classified study subjects in 2 groups: 1) "free" (= secure attachment); 2) "not free" (not secure attachment: anxious-ambivalent or avoidant). Questionnaires were self-administered in the presence of a trained psychologist. Adjusted odds ratios (OR) were calculated using a multiple logistic function. Results No association was found between the different stress scores and the skin diseases considered. The crude odds ratio for life stress events in the previous year was 1.4 (95% CI 0.8–2.7). After multiple adjustment for age, sex, marital status and education, the estimated OR was 1.6 (95% CI 0.8–3.0). One significant association emerged between the adult attachment style defined as “not free” and psychosomatic skin diseases: the adjusted OR was 4.0 (95% CI 1.4–12).  相似文献   
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Recent evidence suggests a direct antiproliferative effect of LHRH agonists on the prostatic carcinoma cell line LNCaP. In the present study the possible presence of a LHRH degrading activity (LHRH-DA) in soluble fractions of LNCaP cell homogenates has been investigated. The results obtained show that an LHRH-DA is present in the soluble fraction of LNCaP cells with apparent Km and Vmax values of 31.6 mu M and 4.5 pmol/min/mu g protein respectively. The degradation pattern of LHRH is characterized by two major initial degradation products identified as LHRH 1-5 and LHRH 1-6 fragments. The degradation of the tracer [pGlu-H-3]LHRH, used as a substrate, is inhibited by synthetic unlabelled LHRH (IC50 7.9 mu M) and by several LHRH agonists with different kinetics and potencies; the LHRH agonist [DSer-(tBu)(6),Gly(10)-Aza]LHRH was the most potent blocker of LHRH-DA present in LNCaP cells; this enzymatic activity is also inhibited in a dose dependent manner by somatostatin, TRH, bacitracin and dithiothreitol. The LHRH-DA present in the soluble fraction of LNCaP cells does not seem to be modified by the deprivation of steroids from the culture medium, In conclusion, the presence in LNCaP cells of a soluble peptidase able to degrade LHRH might reinforce the possibility that the prostate is a target for the action of LHRH and of LHRH analogs.  相似文献   
5.
Objectives: The therapy of advanced, relapsed or refractory primary cutaneous lymphomas is often unsatisfactory. Recent data indicate a favourable pharmacokynetic, pharmacodynamic and toxicity profile of pegylated liposomal doxorubicin (Peg‐Doxo) in primary cutaneous T‐cell lymphomas, while in primary cutaneous B‐cell lymphomas (PCBCLs), the drug efficacy has never been assessed so far. Methods: We performed a prospective phase II pilot clinical trial of Peg‐Doxo monotherapy (20 mg/m2) in PCBCLs. One patient had a marginal zone B‐cell lymphoma and four were affected by diffuse large B‐cell lymphoma‐leg type, all with widespread nodular lesions. Results: All the patients achieved a complete response (CR = 100%) in a short period of time (median 3 months), even when pretreated with radio‐chemotherapy. Two experienced a relapse. At follow‐up, one patient died for progressive disease; four are in CR after 5, 52, 63 and 69 months. As concerning the toxicity profile, the treatment was well‐tolerated, no one decreased or delayed the dose. The haematological toxicity was mild with only one case of grade III neutropenia; a patient showed a grade I neurotoxicity. Dermatological toxicity, in particular the palmar–plantar erythrodysesthesia, did not occurred, probably because of both the low dosages of Peg‐Doxo monotherapy and the oral prophylaxis with pyridoxine. Conclusions: In spite of the small number of patients, it emerges that monochemotherapy with Peg‐Doxo has a significantly high clinical activity and a good safety profile in PCBCLs, even in aggressive forms, compared with other therapeutic regimens, which are completely reviewed. It suggests the need of further investigations in this field.  相似文献   
6.
OBJECTIVE: To evaluate the reliability of contrast-unenhanced power Doppler (CUPD) and contrast-enhanced power Doppler (CEPD) ultrasound (US) assessment of synovial vascularity of knee joint synovitis by prospective comparison with the "gold standard," arthroscopy. METHODS: A total of 18 knees of 17 patients with refractory rheumatoid and psoriatic knee joint synovitis were examined by US. Recognition of PD synovial vessel flow and its spatial arrangement in relation to the pannus/cartilage interface (P/CI) or fluid/synovium interface (F/SI) were studied by CUPD- and CEPD-US after a single intravenous bolus of galactosel palmitic acid (Levovist). Arthroscopy video recordings were reanalyzed by computer image analysis to assess synovial vascular marking. CUPD and CEPD flow signal scores were compared with each other and with corresponding vascular marking scores. Using villous vascular marking as reference, CUPD and CEPD sensitivity and specificity were measured. Interobserver variability was evaluated. RESULTS: Compared with the unenhanced PD method, contrast administration increased the PD flow signal score in 13/18 knees (72.2%), allowing increased detection of F/SI PD flow signal configuration (p < 0.018) and of the coexistence of P/CI and F/SI PD imaging (p < 0.0078). With arthroscopy as reference, contrast-enhanced PD was found to be more useful than the unenhanced method, showing more reproducible PD signal scores (p = 0.05 vs p = nonsignificant), as well as higher sensitivity (80% vs 30%), but lower specificity (62% vs 87%), in the recognition of increased vascularity of synovial villi. Interobserver agreement was 100%. CONCLUSION: The prospective comparison with arthroscopy showed the reliability of the CEPD method in synovial vessel recognition and its potential clinical usefulness in assessment of knee joint synovitis.  相似文献   
7.
The molecular mechanisms that coordinate cell morphogenesis with the cell cycle remain largely unknown. We have investigated this process in fission yeast where changes in polarized cell growth are coupled with cell cycle progression. The orb6 gene is required during interphase to maintain cell polarity and encodes a serine/threonine protein kinase, belonging to the myotonic dystrophy kinase/cot1/warts family. A decrease in Orb6 protein levels leads to loss of polarized cell shape and to mitotic advance, whereas an increase in Orb6 levels maintains polarized growth and delays mitosis by affecting the p34cdc2 mitotic kinase. Thus the Orb6 protein kinase coordinates maintenance of cell polarity during interphase with the onset of mitosis. orb6 interacts genetically with orb2, which encodes the Pak1/Shk1 protein kinase, a component of the Ras1 and Cdc42-dependent signaling pathway. Our results suggest that Orb6 may act downstream of Pak1/Shk1, forming part of a pathway coordinating cell morphogenesis with progression through the cell cycle.  相似文献   
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Autoimmune diseases (ADs) are chronic conditions initiated by the loss of immunological tolerance to self-antigens. The pathogenic hypothesis comprises a complex interaction between genetic, environmental and hormonal factors that interact with an individual over time generating a dysregulation of the immune system leading to disease development. Several polymorphic genes contribute to the development of ADs. Furthermore, age and gender play a major role by influencing hormone levels that can represent the fulcrum unbalancing from susceptibility to protection. Evidences suggest that while all these steps occur, the susceptible individual develops autoantibodies over a long time lapse. Such autoantibody production is genetically determined and finally, their presence seems to determine the clinical presentation of ADs. The genetic predisposition to the developments of autoantibodies and toward the disease process may overlap. The unveiling of these mechanisms could allow not only to treat but also to prevent the development of autoimmune diseases.  相似文献   
10.
Electrochemotherapy (ECT) is a novel treatment for recurrent or in-transit unresectable melanoma metastases based on the administration of anti-neoplastic drugs followed by cancer cell electroporation. Whether ECT can also induce anti-tumour immunity is unclear. We addressed this issue investigating the presence of dendritic cells (DCs) in the inflammatory infiltrate of ECT-treated lesions. Biopsies from melanoma patients (n = 9) were taken before ECT (T0), at d7 and d14 after treatment and studied by immunofluorescence with DCs-related antibodies. Epidermal Langerin+ Langerhans cells (LCs) were the most represented subset before treatment. ECT induced a significant reduction in epidermal LCs number at d7 (p < 0.001), while they were completely replaced at d14. Similarly, the few LCs observed intermingled with metastatic melanoma cells at T0 decreased after treatment (p < 0.001), suggesting an ECT-induced activation of LCs. Consistently, at d1 after ECT (n = 3 patients), LCs were found to express CCR7, which mediates LCs migration to regional lymph nodes, and CD83, the typical DCs maturation marker. In contrast, plasmacytoid DCs (pDCs) were not present at T0, but significantly increased after ECT both in melanoma metastasis (p < 0.001) and perilesionally (p < 0.05). Similarly, CD1c+ dermal DCs (dDCs), observed in low number before ECT, strongly increased at d7 and even more at d14 (p < 0.05 and p < 0.001, respectively). Notably, some dDCs expressed CD83. These data suggest that ECT promotes LCs migration from the tumour to draining lymph nodes and pDCs and dDCs recruitment at the site of the lesion. These findings may help to design new strategies of in situ DCs vaccination in cancer patients.  相似文献   
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