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61.
A previously healthy man from eastern Kansas, USA, sought medical care in late spring because of a history of tick bite, fever, and fatigue. The patient had thrombocytopenia and leukopenia and was given doxycycline for a presumed tickborne illness. His condition did not improve. Multiorgan failure developed, and he died 11 days after illness onset from cardiopulmonary arrest. Molecular and serologic testing results for known tickborne pathogens were negative. However, testing of a specimen for antibodies against Heartland virus by using plaque reduction neutralization indicated the presence of another virus. Next-generation sequencing and phylogenetic analysis identified the virus as a novel member of the genus Thogotovirus.  相似文献   
62.
Serum antibodies from myriad species, particularly birds, can provide key information regarding the transmission and the expansion of the territory of emerging pathogens. Expedient antibody analysis is constrained by a lack of species-specific reagents, a deficiency potentially highlighted by the recent swine-origin influenza A virus (H1N1) outbreak. Available methodologies present difficulties that discourage thorough serologic monitoring of potential disease vectors or hosts. Rapid high-throughput procedures that combined serum amine labeling via biotinylation, contaminant removal, and microsphere-based immunoassays for antibodies to three arboviruses were developed. Agent-specific adaptations of this simple format should facilitate expanded surveillance and diagnostic capabilities regarding pathogens of human and veterinary importance.Serologic analysis of samples obtained from nondomestic animals, birds in particular, can provide key information regarding the transmission and the expansion of the territory of emerging pathogens (1). Unfortunately, species-specific reagents such as antispecies capture antibodies and detection conjugates, necessary for most rapid diagnostic methods, are frequently unavailable due to a lack of commercial interest. Traditional methods for circumventing species constraints often use live pathogens, are technically challenging, or are so time-consuming that large-scale testing becomes impractical (2). Methods that utilize protein G (4) are able to capture and detect mammalian IgG but cannot be used when the antibodies of interest are IgM and IgY, the former being the first of the Igs to be generated after infection and the latter being the avian and reptilian equivalent of IgG. The results of blocking enzyme-linked immunosorbent assay (ELISAs) (3) are sometimes inconsistent, and test sensitivities are dependent on the relative affinities of the competing monoclonal and serum antibodies to the antigens. Disease surveillance that involves the analysis of antibodies in nondomestic species is thus limited.The ideal method for the detection of antibodies in a range of species would be rapid, be capable of high throughput, provide a positive signal (as opposed to a signal reduction via competition), and require a small sample volume. Total antibody measurement would be advantageous, because surveillance is usually conducted without knowledge of the timing of infection. Biotin (vitamin H) is well-known to react with free amine groups on proteins (18). We determined that virus-specific serum antibodies independent of the species of origin could be biotinylated and directly detected in microsphere immunoassays (biotin-MIAs) that were modified from established protocols (11). Here we describe the development of two species-independent antibody detection methods for use with arboviruses, which involve animals as vectors or hosts. The first is a duplex procedure for the detection of antibodies to West Nile (WN) and St. Louis encephalitis (SLE) viruses, and the second is a procedure for the identification of anti-eastern equine encephalitis (anti-EEE) virus antibodies.  相似文献   
63.
64.
Background  The relationship between elevated basal FSH and embryo quality remains a topic of heated discussion among practitioners of ART. Some authors suggest a negative effect of raised FSH on the quality of embryos and therefore on IVF treatment outcome. We postulate that women with elevated FSH who respond well to ovarian stimulation and have embryos to transfer, have the same chance of conceiving like women of a similar age with normal FSH. To test this hypothesis, we studied women with elevated basal FSH who made enough embryos to qualify for blastocyst culture and day 5 embryo transfer. Methods  Analysis of data collected prospectively, on women age 25–43 years, who underwent IVF between January 2005 and December 2006. The women were divided into: those with high FSH (≥10 IU/L) and women with normal FSH (<10 IU/L). We analysed data to show treatment outcome in the two groups, following embryo transfer on day 3 and after transfer on day 5. Outcome measures include number of oocytes retrieved, number of embryos available, implantation rate, pregnancy and live birth rate. Results  Among the 1,858 women who under-went a day 3 transfer, 1,368 had basal FSH ≤ 10 IU/L, and in 492 basal FSH was above 10 IU/L. The average number of oocytes retrieved was lower among women with elevated FSH (10.12 ± 5.6 Vs 6.16 ± 3.9). Women with a normal FSH, had a higher pregnant and live birth rate than those with elevated FSH (43.3% vs 27.9% p = 0.021) and (30.8% vs 17.6% p = 0.028) respectively. 398 women made enough embryos to qualify for extended embryo culture to blastocysts. Of these 366 had an FSH ≤ 10 IU/L and 32 had FSH > 10 IU/L. In this group, there was no significant difference in the pregnancy and live birth rates between women with elevated and those with normal FSH, (67.2% vs 65.6%) and (51.9% vs 43.8%) respectively. In this selected group of women where quantity is not an issue, the quality of embryos was same irrespective of whether the basal FSH was low or high. Conclusion  Women with elevated basal FSH who respond well to stimulation and generate a good number of oocytes / embryos have a chance of becoming pregnant and having a live birth similar to that of women of their age. Women should therefore not be denied the benefits of IVF based solely on the basal FSH level as a subset may respond well and therefore have a good chance of taking home a baby.  相似文献   
65.
First reported prairie dog-to-human tularemia transmission, Texas, 2002   总被引:1,自引:0,他引:1  
A tularemia outbreak, caused by Francisella tularensis type B, occurred among wild-caught, commercially traded prairie dogs. F. tularensis microagglutination titers in one exposed person indicated recent infection. These findings represent the first evidence for prairie-dog-to-human tularemia transmission and demonstrate potential human health risks of the exotic pet trade.  相似文献   
66.
患者,女性,54岁,中国籍,因急性左下肢水肿就诊。既往有子宫肌瘤史2年。腹部及盆腔凹显示左髂总静脉血栓及子宫左下部肌瘤(直径6cm)。考虑静脉血栓系肌瘤压迫髂静脉所致,予抗凝治疗,为缩小子宫体积以减轻其对髂静脉的压力,皮下注射促性腺激素释放激素类似物(GnRHa)3个月。患者对GnRHa冶疗无不良反应,治疗后闭经。4月后复查腹部及盆腔CT显示子宫明显缩小,  相似文献   
67.
Objective: The incidence of Chlamydia pneumoniae and Chlamydia trachomatis infection was studied among infants and young children admitted to hospital for the management of lower respiratory tract infections, over a 12 month period.
Methodology: Respiratory secretions were examined for chlamydiae by cell culture, enzyme-linked immunosorbent assay and polymerase chain reaction-enzyme immunoassay. Sera were tested by micro-immunofluorescence for chlamydial IgG, IgM and IgA. Other bacterial and viral pathogens were also looked for by standard cultural and serological methods.
Results: Of 87 patients aged 2 months-3 years, an aetiologic diagnosis was made in 41 (47.1%). C. pneumoniae and C. trachomatis were each detected in 1 (1.2%) of the patients. Among common bacterial pathogens, Haemophilus influenzae (13.8%) and Streptococcus pneumoniae (8.1%) were the most frequently identified. Respiratory viruses and elevated Mycoplasma pneumoniae antibodies were found in 10.3% and 9.1% of patients, respectively.
Conclusion: Chlamydiae are infrequent causes of community-acquired acute lower respiratory tract infections in infants and very young children in Malaysia.  相似文献   
68.
This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.   相似文献   
69.
The aim of this study was to determine the prognostic value of single and paired measurements of serum concentrations of human chorionic gonadotrophin (HCG) for successful pregnancy following in-vitro fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG concentrations 15 and 22 days after IVF or TET in 198 conception cycles. Cut-off values of serum HCG were determined by a receiver operating characteristic (ROC) curve. On the basis of single HCG samples on day 15 (HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the sensitivity was 71% and the specificity was 77%. The positive predictive value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%, while the negative predictive rate (HCG15 < 150 mIU/ml indicating an abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy. However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio < 15, there was an 84% chance of an abnormal pregnancy. We conclude that a single HCG15 determination combined with the ratio of HCG22 to HCG15 has a higher diagnostic accuracy for prediction of pregnancy outcome than either analysis alone.   相似文献   
70.
To explore the role of nitric oxide (NO) and oxidative stress in the pathogenesis of adhesion formation and in endometriosis-associated infertility, we examined the peritoneal total antioxidant status (TAS) and the concentrations of products of NO metabolism in women with endometriosis (early stage, n = 12; advanced stage, n = 12) and in fertile women without endometriosis (n = 10). Peritoneal CA 125 and oestrogen and progesterone concentrations were also measured to examine their contributions to TAS and the production of NO. We failed to demonstrate any significant difference in TAS and in the products of NO metabolism in peritoneal fluids among women with early and advanced stages of endometriosis compared with fertile women without endometriosis during the early follicular phase. TAS and the concentration of the products of NO metabolism were not related to concentrations of CA 125, oestrogen or progesterone. The concentration of CA 125 in serum, but not in peritoneal fluid, was positively correlated with the severity of endometriosis. The volume of peritoneal fluid and the progesterone concentration were significantly increased in the group with advanced endometriosis. TAS and the concentration of the products of NO metabolism did not increase in peritoneal fluids from women with endometriosis during the early follicular phase. Their role in the pathophysiology of endometriosis needs to be explored further.   相似文献   
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