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31.
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Abramson  JS; Hudnor  HR 《Blood》1994,83(7):1929-1934
Patients infected with influenza A virus (IAV) are at increased risk for bacterial superinfections, and this occurs in association with depressed polymorphonuclear leukocyte (PMNL) function. Recently, we reported that in vitro exposure of human PMNL to granulocyte-macrophage colony-stimulating factor (GM-CSF) reverses IAV-induced cell dysfunction. The present study used an established animal model of IAV infection to examine whether G-CSF and/or GM-CSF can overcome IAV- induced PMNL dysfunction and thereby prevent secondary infections. Preliminary studies determined a dosing schedule of these cytokines that caused significant priming of chinchilla PMNL. In subsequent studies, animals were inoculated intranasally with IAV (day 1) followed 3 days later by Streptococcus pneumoniae, and administered daily intraperitoneal injections with a cytokine or placebo on days 3 through 9. Animals had blood obtained on multiple occasions for PMNL studies, and were followed-up for evidence of pneumococcal disease. Both cytokines caused significant priming of the PMNL chemiluminescence response and this was associated with reversal of the IAV-induced PMNL dysfunction. However, neither cytokine decreased the incidence of pneumococcal disease.  相似文献   
33.
OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
34.
Miller  JS; Alley  KA; McGlave  P 《Blood》1994,83(9):2594-2601
We have recently described a marrow stroma-dependent long-term culture system that supports differentiation of CD34+ human marrow primitive progenitors into natural killer (NK) cells. We postulate that CD7 expression may be an early event in commitment of hematopoietic progenitors to the NK lineage. Here we compare the characteristics of CD34+7- and CD34+7+ marrow cells cultivated in the stroma-based NK culture system. These CD34+ populations were further compared with a marrow derived, more committed, CD34-7+ progenitor to emphasize the continuum of NK development and to highlight differences between progenitors in our assays. No progenitor proliferated when plated in media without stroma, underscoring the importance of stroma in NK differentiation. Plating progenitor populations in interleukin-2 containing media directly on preestablished, allogeneic, irradiated marrow stroma for 5 weeks resulted in CD56+CD3- NK cells; however, characteristics of the cultured populations differed. Fold expansion and cloning efficiency of the CD34+7+ population, determined by a functional limiting dilution assay was significantly higher than of the CD34+7- or CD34+7+ populations. This suggests that the CD34+7+ population is highly enriched for an NK progenitor and a possible intermediate in NK lineage differentiation. Further dividing the CD34+7+ population by the relative fluorescence of CD7 into CD34+7+dim and CD34+7+bright populations showed that the CD34+7+bright population exhibited a significantly higher cloning frequency than parallel experiments with CD34+7+dim cells (11.8% +/- 2.4% v 2.4% +/- 0.7%, n = 6; P = .005). Plating of the more primitive CD34+7- population in a transwell system (which separates progenitors from stroma by a microporous membrane) prevents differentiation into NK cells. In contrast, plating of CD34+7+ progenitors in transwells resulted in generation of NK cells. These data suggest that primitive, but not more mature NK progenitors may require direct contact with stroma for the initial differentiation steps. Finally, differentiation of the NK progenitors in this stroma-dependent model results in expression of CD2 not present on any of the starting populations. This observation suggests that marrow stroma can stimulate CD2 expression on NK progenitors in a previously undescribed fashion that may be analogous to the thymic effect on CD2 expression in immature T lymphocytes. These observations identify early steps in the commitment of primitive marrow CD34+ hematopoietic progenitors to a lymphoid lineage and underscore the importance of coexpression of CD7 with CD34 as an early lymphoid commitment characteristic and direct progenitor-stroma interactions in this process.  相似文献   
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Background

Because of the time-consuming aspect of geriatric assessments, cancer specialists are seeking shorter screening tools to distinguish fit and frail patients. We analyzed the predictive value of the Geriatric 8 (G8) and Identification of Seniors at Risk for Hospitalized Patients (ISAR-HP) in elderly patients with lung cancer.

Patients and Methods

From January 2014 to April 2016, the data from patients with lung cancer aged > 70 years at 2 teaching hospitals in the Netherlands were included in a database. The patients were classified as potentially frail if they had a G8 of ≤ 14 or ISAR-HP of ≥ 2.

Results

Of the 142 included patients (median age, 77 years; interquartile range, 73-82 years), 108 (76%) were potentially frail. After correction for possible confounders, the potentially frail patients had a significantly greater risk of 1-year mortality (hazard ratio [HR], 4.08; 95% confidence interval [CI] 1.67-9.99; P = .02). Higher disease stage (HR, 1.72; 95% CI, 1.40-2.12; P < .001) was also a significant predictor of mortality; however, initial treatment (standard or otherwise) and age were not. When using both screening instruments separately, an impaired score on the G8 and higher disease stage were the variables remaining in the regression analyses (HR for impaired G8, 3.01; 95% CI, 1.35-6.72; P < .001). Patients with impaired scores on the ISAR-HP and G8 had more geriatric impairments than did patients with only an impaired G8 score.

Conclusion

G8 screening is useful for the prognostication of elderly patients with lung cancer and could be used in combination with ISAR-HP to increase specificity at the cost of sensitivity. Using the ISAR-HP as the only screening tool would be insufficient.  相似文献   
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Objectives

Staging in case of a borderline tumor of the ovary (BOT) is a controversial issue. Upstaging is not uncommon, but this occurs especially with presumed stage I serous borderline tumors. There are only a few documented cases of BOTs of non-serous histology that were not confined to the ovary. The aim of this study was to assess the incidence of non-invasive and invasive implants in the omentum and other (extra)pelvic peritoneal surfaces in patients with a mucinous BOT (mBOT).

Methods

A retrospective cohort study was performed in three hospitals in the Netherlands. All patients with a histopathological diagnosis of mBOT diagnosed from January 1st 1990 to December 1st 2015 were identified and included when the inclusion criteria were met.

Results

In total, 74 patients were included. Of these 74 patients, 46 (62.2%) underwent a staging procedure. In 12 (26.1%) patients, only omental tissue was obtained, in 32 (69.6%) patients, omental tissue and peritoneal biopsies were obtained and in two (4.3%) patients, only peritoneal biopsies were obtained. No implants were seen upon microscopic examination in any of the patients. Two patients (3%) developed a recurrence.

Conclusions

Because no extra-ovarian disease was found, staging procedures in the case of an mBOT may be omitted. However, the actual perioperative decision for staging or not should be taken in the context of a frozen section diagnosis, which is not always accurate and straightforward. Recurrence with malignant disease is rare after mBOT. The value of post-treatment surveillance seems limited after bilateral salpingo-oophorectomy.  相似文献   
40.
Objectives: We examined the associations between preterm birth and low birth weight and maternal caries history, maternal periodontal status, and salivary levels of mutans streptococci and Lactobacilli. Design: This study was a matched case–control study in women during their pregnancy or up to 8 weeks after delivery. Subjects and methods: Thirty‐four women delivering before 37 weeks gestation were recruited along with 73 term controls matched for age and race/ethnicity. Demographic and obstetric information was collected from questionnaires and medical records and oral examinations along with commercial salivary tests were completed within the study groups. Main outcome measures: The main outcome variables were the preterm birth and low birth weight status. The independent variables measured were the salivary levels of Lactobacilli and mutans streptococci and the caries and periodontal status of the subjects. Results: The odds ratio comparing low levels of bacteria in preterm mothers and controls was statistically significant for Lactobacilli (odds ratio (OR) = 3.45, 95% confidence interval (CI) = 1.27 to 10.00) and almost significant for mutans streptococci (OR = 2.63, 95% CI = 0.95 to 8.33). Clinical caries and periodontal disease measures did not differ significantly between groups. Conclusion: Within the limitation of our study, low levels of Lactobacilli in saliva were found to be associated with preterm birth.  相似文献   
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