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Brooke T. Mossman Arti Shukla Nicholas H. Heintz Claire F. Verschraegen Anish Thomas Raffit Hassan 《The American journal of pathology》2013,182(4):1065-1077
Malignant mesothelioma (MM) is a relatively rare but devastating tumor that is increasing worldwide. Yet, because of difficulties in early diagnosis and resistance to conventional therapies, MM remains a challenge for pathologists and clinicians to treat. In recent years, much has been revealed regarding the mechanisms of interactions of pathogenic fibers with mesothelial cells, crucial signaling pathways, and genetic and epigenetic events that may occur during the pathogenesis of these unusual, pleiomorphic tumors. These observations support a scenario whereby mesothelial cells undergo a series of chronic injury, inflammation, and proliferation in the long latency period of MM development that may be perpetuated by durable fibers, the tumor microenvironment, and inflammatory stimuli. One culprit in sustained inflammation is the activated inflammasome, a component of macrophages or mesothelial cells that leads to production of chemotactic, growth-promoting, and angiogenic cytokines. This information has been vital to designing novel therapeutic approaches for patients with MM that focus on immunotherapy, targeting growth factor receptors and pathways, overcoming resistance to apoptosis, and modifying epigenetic changes.CME Accreditation Statement: This activity (“ASIP 2013 AJP CME Program in Pathogenesis”) has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint sponsorship of the American Society for Clinical Pathology (ASCP) and the American Society for Investigative Pathology (ASIP). ASCP is accredited by the ACCME to provide continuing medical education for physicians.The ASCP designates this journal-based CME activity (“ASIP 2013 AJP CME Program in Pathogenesis”) for a maximum of 48 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.CME Disclosures: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.Malignant mesotheliomas (MMs), among the most aggressive tumors, arise most often from the mesothelial cells that line the pleura, peritoneum, and, occasionally, the pericardium. Because of the multifaceted properties of mesothelium that maintain a protective barrier but also produce components of the extracellular matrix, hyaluronan and other lubricants, chemokines and cytokines, and fibrinolytic and procoagulant factors, understanding its complex biology is a challenge. The intermediate filament pattern of mesothelial cells, suggesting an epithelial–mesodermal hybrid morphology, and their several patterns of differentiation during the neoplastic process suggest their transformation to malignancy is complicated and raises the question of whether one is studying a single tumor type or multiple subgroups of tumors.MMs are most commonly attributed to occupational exposures to asbestos, a regulatory term for a group of fibrous silicates that occur as needle-like amphiboles (crocidolite, amosite tremolite, anthophyllite, and antigorite) or curly serpentine (chrysotile) fibers. Although each of these fibers has its own distinctive properties, the fibrous nature and biopersistance of these inhaled fibers may be key to carcinogenic events that occur during the long latency periods (mean, 30 to 45 years) of most MMs. Most intensely investigated are chrysotile, the most commonly used type of asbestos historically (>90% use worldwide), and crocidolite, the asbestos type associated most often with MMs in humans1,2 (Figures 1 and 2). The morphology of crocidolite asbestos is similar to nonasbestos fibers of erionite or Libby amphibole, other naturally occurring minerals associated with the development of MMs.5,6 However, 20% to 25% of individuals with MM have no documented exposure to asbestos or other fibers, suggesting familial susceptibility (sporadic or idiopathic MM), unknown exposure to in-place or naturally occurring asbestos, or other causative agents, such as chemicals, radiation, and viruses.7Open in a separate windowFigure 1Properties of chrysotile (white) asbestos. A: Image of bundle of curly chrysotile fibers before processing. B: Scanning electron micrograph of chrysotile fibers (arrows) causing deformation of red blood cells. Chrysotile is positively charged, hemolytic, and cytolytic, primarily due to its magnesium content. Leaching of magnesium renders chrysotile less toxic and also results in chrysotile fiber dissolution over time. C: Scanning electron micrograph of interaction of long chrysotile fiber with the respiratory epithelium of the alveolar duct junction after inhalation by rats. Arrowheads show points of contact with and between epithelial cells. Subsequent penetration into and between cells leads to fiber deposition in the lung interstitum and access to the visceral pleura and pleural space. D: Polarized microscopy showing chrysotile fibers and fibrils.Photomicrograph is a courtesy of Lee Poye (J3 Resources, Inc., Houston, TX) Original magnification, ×100.Open in a separate windowFigure 2Properties of crocidolite, or blue, asbestos. A: Riebeckito ore showing veins of crocidolite asbestos fibers (arrow) before processing. B: Scanning electron micrograph showing morphology of needle-like fibers. C: Early penetration of a crocidolite fiber into the differentiated tracheobronchial epithelium in tracheal organ culture. D: Growth of metaplastic cells over long fibers of crocidolite observed at 1 month in this model.3 These events have not been captured in the pleura in animal inhalation models or in clinical specimens in humans, but mesothelial cells undergo proliferation, as measured by cell counts, or immunochemical markers have been observed in response to crocidolite asbestos in vitro and after inhalation by rats.4Because asbestos fibers neither appear to be metabolized nor directly interact with DNA, they are unlike most chemical carcinogens. The sensitivity of human mesothelial cells to fibers of high aspect (length to diameter) ratio is also perplexing, as are the phenomena governing fiber transport to the parietal pleura where most MMs are thought to develop. Although much insight exists on understanding how fibers (particularly high iron-containing amphibole asbestos types) generate reactive oxygen and nitrogen species to induce inflammation and cell signaling pathways important in proliferation and transformation, how these cellular events converge in the pathogenesis of MM remains enigmatic. This review amalgamates current observations in the field and their implications in strategies to prevent and manage MMs in patients. 相似文献
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The aim of the study was to explore whether expression of proliferation and hypoxia-related proteins differs in the central parts and the invasive front in endometrial carcinomas. Proliferation-associated proteins Ki67 and cyclin A; cell cycle regulators p16, p21, p53, cyclin D1, cyclin E, and cdk2; and hypoxia-inducible factor 1alpha and its downstream factors glucose transporter 1, carbonic anhydrase IX, and vascular endothelial growth factor were immunohistochemically stained in paraffin-embedded specimens from endometrioid (n = 33), mucinous (n = 1), and serous (n = 5) endometrial carcinomas. The percentages of positive cells at the invasive front and central tumor parts were scored and compared. Ki67 (P < .001), cyclin E (P = .018), p16 (P = .003), and cdk2 (.001) were expressed higher at the invasive front than centrally (Wilcoxon signed ranks test). Higher expression of these antigens at the invasive front was seen in 31 of 38 cases for Ki67, in 16 of 39 cases for cyclin E, in 15 of 39 cases for cdk2, and in 11 of 39 cases for p16. The other cell cycle proteins and the hypoxia-related factors did not show significant differences in expression between the central parts and the invasive front. Endometrial carcinomas clearly show an invasive front that is characterized by higher proliferation and progressive derailment of the cell cycle regulators cyclin E, p16, and cdk2, but not by an increased hypoxic response. 相似文献
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26.
Marian K. Engberts MD Banut S. M. Verbruggen MD PhD Mathilde E. Boon MD PhD Maarten van Haaften MD PhD A. Peter M. Heintz MD PhD 《Cancer cytopathology》2007,111(5):269-274
BACKGROUND.
The objective of this study was to investigate whether the presence of vaginal Candida or dysbacteriosis predisposes women to an increased susceptibility for (pre)neoplasia over time.METHODS.
A retrospective, longitudinal, cohort study was performed and was conducted in a population of 100,605 women, each of whom had 2 smears taken over a period of 12 years as part of the Dutch Cervical Screening Program. From these women, a cohort of 1439 women with Candida and a cohort of 5302 women with dysbacteriosis were selected as 2 separate study groups. The control cohort consisted of women who had completely normal cervical smears (n = 87,903 women). These groups were followed retrospectively over time. The odds ratios (OR) for squamous abnormalities in the follow‐up smear for the women in these 3 cohorts were established.RESULTS.
The dysbacteriotic cohort was significantly more likely to have low‐grade squamous intraepithelial lesions (LSIL) and high‐grade squamous intraepithelial lesions (HSIL+) in their follow‐up smear (OR, 1.85; 95% confidence interval [95% CI], 1.28–2.67 and OR, 2.00; 95% CI, 1.31–3.05, respectively) compared with women in the control group. In contrast, the Candida cohort had no significantly increased or decreased risk of developing SIL. The equivocal diagnosis ‘atypical squamous cells of undetermined significance’ was rendered significantly more often in the follow‐up smear of both study cohorts (Candida cohort: OR, 1.42; 95% CI, 1.03–1.95; dysbacteriotic cohort: OR, 1.44; 95% CI, 1.22–1.71).CONCLUSIONS.
The results from this study indicated that the presence of Candida vaginalis was not associated with an increased risk for SIL over time. In contrast, women with dysbacteriosis had a significantly increased risk of developing (pre)neoplastic changes. These findings should be taken into account in further research concerning predisposing factors for cervical carcinogenesis. Cancer (Cancer Cytopathol) 2007. © 2007 American Cancer Society. 相似文献27.
Dittmar M Heintz A Hardt J Egle UT Kahaly GJ 《Metabolism: clinical and experimental》2003,52(12):1551-1557
Obesity is considered a primary risk factor for cardiovascular disease and related mortality. The current study aimed to investigate the efficacy of minimal invasive gastric banding (GB) surgery for reducing caloric intake in morbid obesity, and to analyze the effects of weight loss on body composition and metabolic and psychosocial outcomes. Twenty-six adult severely obese patients (mean body mass index [BMI], 48.1 kg/m(2); range, 42 to 56) underwent adjustable silicone laparoscopic GB. Nine additional obese patients who declined surgery were treated with metformin (2 g daily) and served as a small additional group (BMI, 50.5 kg/m(2); range, 41 to 68). Presurgery and 17 +/- 2.2 months postoperatively, body composition (fat mass [FM], lean body mass [LBM], body water) and serum parameters (lipids, glucose, thyrotropin-stimulating hormone [TSH]) were determined. Quality of life (QoL) was evaluated by a standardized self-rating questionnaire (Short Form-36 [SF-36]), and supplemented by measures of physical complaints and psychological distress. After GB, weight loss was 21 +/- 14.9 kg (14%, P <.001). It was associated with a decrease in FM by 14 +/- 8.6 kg (18%, P <.001), LBM by 4 +/- 2.7 kg (5%, P <.001), body water by 4 +/- 3.4 L (7%, P <.01), systolic blood pressure by 16 +/- 26.3 mm Hg (10%, P <.05), total cholesterol by 0.69 +/- 1.29 mmol/L (12%, P <.05), and low-density lipoprotein cholesterol (LDL-C) by 0.38 +/- 0.39 mmol/L (10%, P <.05). Highly significant interactions between surgery and time were noted for weight (P <.005), BMI (P <.005), and FM (P <.007, analysis of variance [ANOVA]). Preoperatively, 14 of 26 patients (54%) had high fasting blood sugar levels (type 2 diabetics) and 11 (42%) had impaired glucose tolerance, whereas postoperatively, for baseline glucose levels a trend to decrease was noted. Neither malabsorption nor anemia was observed. QoL improved after GB; in particular, physical functioning and well being increased (P <.01), and somatic complaints (eg, dyspnea and heart complaints, pain in legs and arms) markedly decreased (P =.008). In the metformin group, neither relevant weight loss nor a significant decrease of biochemical values was observed. Minimal invasive GB is a successful therapeutic tool for reducing FM in morbidly obese patients. Weight loss resulted in improved metabolic parameters, suggesting a lowered atherogenic risk. 相似文献
28.
The JB6 mouse epidermal cell system has been used extensively as an in
vitro transformation model for the study of tumor promotion. The standard
JB6 cell assay for promotion of transformation is carried out in soft agar
or other anchorage independent conditions. The present study was directed
to the development of an in vivo model to distinguish the promotion
resistant (P-) and promotion sensitive (P+) progression phenotypes. Results
indicate that the grafting assay distinguishes P- and P+ cells in vivo with
P+ but not P- cells forming tumors within 7-9 weeks. Expression of dominant
negative mutant jun TAM67 blocks both anchorage independent transformation
response and graft bed tumor formation by P+ cells, suggesting that the
requirement for AP-1 activation in transformation now applies in vivo.
Expression of mutated p53 produced a gain of P+ phenotype in P- cells in
vitro, but not in vivo. Histochemical and Northern blot analysis for
expression of various keratinocyte markers revealed no evidence for
expression, suggesting a loss of keratinocyte markers following
establishment in culture. In summary, the skin-grafting assay described in
this study appears to be a valid in vivo assay for distinguishing the
preneoplastic progression phenotypes represented by JB6 P- and P+ cells.
相似文献
29.
Second-look and second surgery: second chance or second best? 总被引:2,自引:0,他引:2
About 40 years ago, second-look laparotomy (SLL) was introduced to evaluate, surgically and pathologically, primary treatment in case a clinical complete remission was obtained in ovarian cancer patients. But does SLL increase the disease-free or overall survival? Important technical aspects of the procedure as: how many biopsies should be taken, can laparoscopy be replaced by laparotomy and should complete lymphadnectomy be performed at SLL, are still not clarified. This and maybe even more important issues, are disputed in literature: for instance, should a SLL be done at all, or should a SLL be performed in order to do a secondary cytoreduction in case tumour is found at the operation. If clinical remission is reached in more than 50% of the patients with advanced disease, tumour still can be found at SLL. If no tumour is found at SLL, macroscopically or microscopically, the operation is redundant. Apart from this, the recurrence rate after such a "negative SLL" is about 35%. Whether tumour found at SLL should be removed will depend on the fact if the tumour still is responsive to chemotherapy. To minimise the chance of tumour resistance, secondary surgery should be done as early as possible during treatment. Therefore, an interval debulking will be the intervention of choice. So, as long as there is no evidence that SLL increases the survival in ovarian cancer patients, it should be done in a research setting only. Also, the usefulness of secondary surgery for recurrent disease mainly depends on the chemo-sensitivity of the tumour. After a complete remission, which lasts for more than a year, complete secondary cytoreduction, again followed by chemotherapy, improves survival. 相似文献