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61.
Meningoencephalic herniation into the middle ear is a rare and potentially life-threatening condition that may require prompt surgical intervention. Preoperative diagnosis is based on a high index of suspicion. Sometimes, however, meningoencephalic herniation is discovered during surgery. High-resolution computed tomography and magnetic resonance imaging should be performed to confirm the diagnosis and to evaluate the extension of the herniated tissue. This article discusses the diagnostic approach, management strategy, and surgical technique used in 27 patients with meningoencephalic herniation. In an attempt to avoid infective complications, the authors used the middle cranial approach in patients with large herniations.  相似文献   
62.
Various H-2 and Qa/Tla region encoded class I glycoproteins expressed on the surface of resting and activated T- and B-lymphocytes were compared by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). The isoelectrophoretic patterns of the H-2K, H-2D, Qa-2 and Qa-1 molecules isolated from activated T-lymphocytes were more isoelectrically heterogeneous and/or possessed species with a more basic pI than the same molecules isolated from resting T- and B-cells or activated B-lymphocytes. The differences in charge heterogeneity of class I molecules between activated T-cells and the other cell subpopulations were abolished by treatment with: (1) endoglycosidase F which removes N-linked oligosaccharides from glycoproteins, and (2) neuraminidase which removes sialic acids from carbohydrate side chains. Thus, the increased charged heterogeneity of class I molecules expressed by activated T-cells is due to altered sialylation of their N-linked oligosaccharides. These results indicate that a mechanism exists, upon activation of T-lymphocytes, for alteration (desialylation) of the carbohydrate moieties of class I molecules.  相似文献   
63.
Background: Papillary thyroid carcinoma (PTC), which may be sporadic (95%) or familial (5%), has a prevalence adjusted for age in the general population of 1:100 000. Somatic rearrangements of the RET proto-oncogene are present in up to 66% of sporadic tumours, while they are rarely found in familial cases.

Purpose: In order to determine if some variants of this gene, or a combination of them, might predispose to PTC, we looked for an association of RET haplotype(s) in PTC cases and in controls from four countries matched for sex, age, and population.

Methods: Four single nucleotide polymorphisms (SNPs) across the RET coding sequence were typed and haplotype frequencies were estimated. Genotype and haplotype distributions were compared among these cases and controls.

Results: Ten haplotypes were observed, the seven most frequent of which have been previously described in sporadic Hirschsprung patients and controls. The single locus analyses suggested association of exon 2 and exon 13 SNPs with sporadic PTC. The haplotype analysis showed over-representation of one haplotype in French and Italian sporadic PTC, whereas a different haplotype was significantly under-represented in French familial PTC.

Conclusions: Our data suggest that some variants of RET and some specific haplotypes may act as low penetrance alleles in the predisposition to PTC.

  相似文献   
64.
OBJECTIVES: To evaluate and compare epidermal growth factor type-1 receptor (EGF-R1) expression in short term and established cervical cancer cell lines generated from primary and metastatic/recurrent sites of disease. To evaluate the sensitivity of cervical cancer cell lines to treatment with a chimeric MAb against EGFR-1 (Cetuximab). METHODS: EGFR-1 expression was evaluated by flow cytometry on 22 cervical cancer cell lines including 14 primary cervical cancer cell lines obtained from cervical biopsies (11 patients) and recurrent sites of disease (three patients) as well as eight established cell lines. Tumor cell lines were tested for sensitivity to Cetuximab-mediated complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) in 51Cr release assays. Finally, Cetuximab-mediated inhibition of cell proliferation was also tested. RESULTS: Fourteen out of fourteen (100%) primary tumors and seven out of eight (87.5%) established cervical cancer cell lines expressed EGFR-1 by flow cytometry. Cell lines from recurrent/metastatic sites of disease expressed higher levels of EGFR-1 when compared to those obtained from primary sites (p>0.05). Minimal CDC was detected in the majority of cervical cancer cell lines exposed to complement+/-Cetuximab in the absence of peripheral blood lymphocytes (PBL). In contrast, cervical tumor cell lines were found highly sensitive to Cetuximab-mediated ADCC when challenged with PBL from either healthy donors or cervical cancer patients. Importantly, ADCC was further increased in the presence of complement. Finally, tumor proliferation was significantly inhibited by Cetuximab in all cervical tumors tested. CONCLUSIONS: EGFR-1 is highly expressed in primary and recurrent cervical tumors. Cetuximab might be a novel and attractive therapeutic strategy in patients harboring chemotherapy-resistant, recurrent, or metastatic cervical cancer.  相似文献   
65.
PURPOSE: There are several options in the treatment of fecal incontinence; it is often difficult to choose the most appropriate, adequate treatment. The consolidated experience gained in the urologic field suggests that sacral nerve stimulation may be a further option in the choice of treatment. The aim of our study was to evaluate the preliminary results of the peripheral nerve evaluation test obtained in a multicenter collaborative study on patients with defecatory and urinary disturbances. METHODS: Forty patients (9 males; mean age, 50.2; range, 26–79 years) underwent the peripheral nerve evaluation test, 28 (70 percent) for fecal incontinence and 12 (30 percent) for chronic constipation. Fourteen (35 percent) patients also had urinary incontinence; six had urge incontinence, two had stress incontinence, and six had retention incontinence. Associated diseases were scleroderma (2 patients), spinal injuries (4 patients), and syringomyelia (1 patient). All the patients underwent preliminary investigations with anorectal manometry, pudendal nerve terminal motor latency testing, anal ultrasound, defecography, and if required, urodynamic tests. The electrode for sacral nerve stimulation was positioned percutaneously under local anesthesia in the S2 (4), S3 (34), or S4 (1) foramen unilaterally (1 patient not accounted for because of no response to acute test), based on the best motor and subjective responses of paresthesia of the pelvic floor. Stimulation parameters were average amplitude, 2.8 (range, 1–6) V and average frequency, 15 to 25 Hz. RESULTS: The mean duration of the tests was 9.9 (range, 7–30) days; tests lasting fewer than seven days were not evaluated. There were four early displacements of the electrode. In 22 of the 25 evaluable patients with fecal incontinence, there was an improvement of symptoms (88 percent), and 11 (44 percent) were completely continent to liquid or solid stools, whereas in 7 symptoms were unchanged. Mean number of episodes of liquid or solid stool incontinence per week was 8.1 (range, 4–18) in the prestimulation period and 1.7 (range, 0–12) during the peripheral nerve evaluation test. (P=0.001; Wilcoxon's signed-rank test). The most important manometric findings were: increase of maximum rest pressure (39.4 ± 7.3vs. 54.3 ± 8.5 mmHg;P=0.014, Wilcoxon's test) and maximum squeeze pressure (84.7 ± 8.8vs. 99.5 ± 1.1 mmHg;P=0.047), reduction of initial threshold (63.6 ± 5.2vs. 42.4 ± 4.7 ml;P=0.041) and urge sensation (123.8 ± 0.6vs. 78.3 ± 8.9 ml;P=0.05). An improvement was also found in patients with constipation, with reduction in difficulty emptying the rectum, with prestimulation at 7 (range, 2–21) episodes per week and end of peripheral nerve evaluation test at 2.1 (range, 0–6) episodes per week, (P<0.01) and in the number of unsuccessful visits to the toilet, which dropped from 29.2 (7–24) to 6.7 (0–28) per week (P=0.01). The most important manometric findings in constipated patients were an increase in amplitude of maximum squeeze pressure during sacral nerve stimulation (prestimulation, 63 ± 0 mm Hg; end of peripheral nerve evaluation test, 78 ± 1 mm Hg;P=0.009) and a reduction in rectal volume for urge threshold (prestimulation, 189 ± 52 ml; end of peripheral nerve evaluation test, 139 ± 45 ml;P= 0.004). CONCLUSIONS: In functional bowel disorders short-term sacral nerve stimulation seems to be a useful diagnostic tool to assess patients for a minor invasive therapy alternative to conventional surgical procedure.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, June 24 to 29, 2000.  相似文献   
66.
Cyclooxygenase (COX)-1 and -2 catalyze the formation of prostaglandins (PG). Given the role of COX and PG during intrathymic T cell development in the mouse, we investigated the expression and localization of these isozymes in the human thymus. mRNA and proteins correspondent to COX-1 and -2 were observed from whole thymus extracts. By immunohistochemistry, COX-2 was selectively localized in the medulla and it was predominant in a subset of stromal cells. By contrast, COX-1 was diffusely and exclusively present in the cortex, both in thymocytes at early stages of differentiation and in cytokeratin-positive epithelial cells, as demonstrated by double immunostaining and flow cytometry analysis. COX-2-positive cells in the medulla expressed cytokeratin and HLA-DR molecules, but they were negative for dendritic or macrophagic antigens. In addition, COX-2-positive cells expressed both the epidermal growth factor receptor and its ligand, the transforming growth factor-alpha. The inducible isoform of the PGE(2) synthase was also present in the same cells, while was absent from COX-1-expressing cells of the cortex. Finally, electron microscopy confirmed that COX-2 was mainly localized in the cytoplasm of cytokeratin-positive cells, along the rough endoplasmic reticulum. In conclusion, COX-2 and the inducible isoform of PGE(2) synthase appear to be constitutively and selectively present in medullary epithelial cells of the human thymus, whereas COX-1 is predominantly present in the thymic cortex, both in the stroma and in developing thymocytes.  相似文献   
67.
68.
Anticoagulant prophylaxis for preventing venous thromboembolism (VTE) is a worldwide established procedure in hip and knee replacement surgery, as well as in the treatment of femoral neck fractures (FNF). Different guidelines are available in the literature, with quite different recommendations. None of them is a multidisciplinary effort as the one presented. The Italian Society for Studies on Haemostasis and Thrombosis (SISET), the Italian Society of Orthopaedics and Traumatology (SIOT), the association of Orthopaedists and Traumatologists of Italian Hospitals (OTODI), together with the Italian Society of Anesthesia, Analgesia, Resuscitation, and Intensive Care (SIAARTI) have set down easy and quick suggestions for VTE prophylaxis in hip and knee surgery as well as in FNF treatment. This inter-society consensus statement aims at simplifying the grading system reported in the literature, and its goal is to benefit its clinical application. Special focus is given to fragile patients, those with high bleeding risk, and those receiving chronic antiplatelet (APT) and vitamin K antagonists treatment. A special chapter is dedicated to regional anaesthesia and VTE prophylaxis.  相似文献   
69.
Familial Mediterranean fever (FMF) is a recessive, autosomal, auto-inflammatory disorder characterised by brief, recurring, self-limited episodes of fever and serositis resulting in abdominal, chest, joint and muscular pain; it is the most common of the periodic hereditary fevers and mostly affects Mediterranean populations. Daily administration of colchicine, a tricyclic alkaloid with anti-microtubule and anti-inflammatory properties, prevents the recurrence of FMF attacks and the development of secondary (AA) amyloidosis, the major long-tem complication of FMF. Colchicine is generally safe and well-tolerated; nevertheless, 5–10 % of FMF patients do not respond to conventional treatment, while another 2–5 % of patients are colchicine-intolerant because of toxicity issues, leading physicians to search for alternative therapeutic strategies. Recent new insights into the mechanisms of auto-inflammation add further proof to the efficacy of IL-1 targeting drugs in colchicine non-responder/intolerant FMF patients. A systematic study of relevant literature through PubMed/Medline was performed in order to identify publications reporting IL-1β biological treatment of FMF. Treatment methods, comorbidities, clinical response and side effects in literature case reports were analysed, as well as recent advances in the pathogenesis of auto-inflammation mechanisms in FMF and the causes of colchicine resistance or toxicity in common clinical practice. The paradigmatic experience of an FMF patient with severe FMF mutations (M694V/M694V) suffering from colchicine toxicity and successfully treated with anakinra is also reported. The present data show that anti-IL-1β biological treatment is actually a therapeutic option for FMF patients unresponsive or intolerant to colchicine or in FMF patients with concomitant vasculitis.  相似文献   
70.
In vivo and in vitro effects of different anaesthetics on platelet function   总被引:3,自引:0,他引:3  
Different effects of thiopental, propofol and sevoflurane on platelets have been reported. Patients undergoing thyroid surgery were anaesthetized with thiopental-fentanyl-sevoflurane (n = 11) or propofol-fentanyl-sevoflurane (n = 9). Platelet aggregation and thromboxane A2 generation were studied at baseline, and at the end of anaesthesia induction and surgery. Dose-response experiments were also performed in vitro with single agents. Thiopental-fentanyl-sevoflurane significantly reduced collagen-induced aggregation by the end of induction, while ADP-induced aggregation and thromboxane generation were unaffected. Propofol-fentanyl-sevoflurane had no effect on platelets. Thiopental dose-dependently inhibited platelets in vitro, while fentanyl or propofol did not. In conclusion, thiopental reduces platelet function both ex vivo and in vitro and propofol might be considered haemostatically safer.  相似文献   
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