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71.
72.
Defects in human methionine synthase in cblG patients   总被引:6,自引:0,他引:6  
  相似文献   
73.
74.
目的:研究Down’s 综合征动物模型trisomy 16 结肠神经系发育和先天性巨结肠(HD) 病变肠管蛋白基因产物9-5(protein gene product9 .5 ,PGP9-5) 的神经表达。方法:Trisomy 16 鼠培育;细胞遗传学分析;Trisomy 16 鼠结肠和HDPGP9-5 免疫组织化学。结果:(1)Trisomy 16 鼠结肠神经系发育异常,肌间神经丛发育迟缓,粘膜下神经丛缺失,结肠末端有5 mm 的无神经节区,但结肠系膜神经发育良好;(2)HD狭窄段肠管PGP9-5 阳性神经纤维大量增生,神经节细胞缺如。结论:(1)Trisomy 16 鼠具有稳定的遗传学特征,可能伴先天性巨结肠。(2) 由于HD 狭窄段肠管神经节细胞缺失,增生的PGP9-5 阳性神经纤维是肠道外源性神经的代偿,对其神经元的性质尚有待确定。(3)HD有遗传倾向  相似文献   
75.
BACKGROUND: There is currently an epidemic of tinea capitis in urban areas of developed countries caused by Trichophyton tonsurans. Recurrence or re-infection with dermatophyte is not uncommon after adequate oral treatment. Asymptomatic carriers who are household contacts may partly explain this observation by forming a reservoir for infection. PATIENTS/METHODS: Two-hundred and nine household contacts of patients with tinea capitis were examined and screened for asymptomatic carriage of dermatophyte. RESULTS: Only 7.2% had clinically evident disease yet 44.5% had silent fungal carriage on the scalp. Children under 16 years were much more likely to be carriers than adults (P < 0.001) and males were less likely than females to be affected (P < 0.01). CONCLUSION: This evidence poses questions about factors relevant in transmission of dermatophytes. The authors propose that all household contacts of patients with tinea capitis should be offered screening to eradicate a potential reservoir of infection.  相似文献   
76.
As of April 2022, the Omicron BA.1 variant of concern of SARS-CoV-2 was spreading quickly around the world and outcompeting other circulating strains. We examined its stability on various surfaces and found that this Omicron variant is more stable than its ancestral strain on smooth and porous surfaces.  相似文献   
77.
Collection of pluripotential hematopoietic stem cells by cytapheresis   总被引:1,自引:1,他引:1  
Lasky  LC; Ash  RC; Kersey  JH; Zanjani  ED; McCullough  J 《Blood》1982,59(4):822-827
Successful complete hematopoietic reconstitution (CHR) using nonleukemic peripheral stem cells (PSC) after marrow ablation has been reported in animals but not man. Previous studies of cytapheresis products from humans, as a prelude to use for CHR, have documented the presence of committed myeloid (CFU-GM) and erythroid (BFU-E) precursors. We have examined mononuclear cell (MNC) products collected on the Fenwal CS3000 Blood Cell Separator for these plus the more primitive mixed (granulo-, erythro-, mono-, and megakaryocytic) cell colony-forming units (CFU-GEMM) and for various lymphocytic subpopulations (LSP). One to two-hour products contained 36 +/- 7 CFU- GEMM/10(6) MNC (mean +/- SE, n = 8) or 490 +/- 131/ml product. This compared favorably with blood (23 +/- .4/10(6) MNC or 46 +/- 8/ml, n = 14) and bone marrow (146 +/- 58/10(6) MNC, n = 12). Collection efficiency for E-rosette-positive cells approximated that for total lymphocytes and was variable for other LSP. Recovery of CFU-GEMM after freezing in 10% dimethylsulfoxide at a controlled rate and storage in liquid N2 was 54% +/- 8% (n = 8). Cytapheresis collection of large numbers of pluripotent hematopoietic precursors and demonstration of adequate recovery of these after cryopreservation, both previously unreported, are significant steps toward eventual CHR using nonleukemic PSC.  相似文献   
78.
Perineal hernia is a rare complication following laparoscopic abdominoperineal resection (APR) for rectal cancer. We present two case reports of perineal hernia following laparoscopic APR and discuss their management. We suggest that they developed because the pelvic peritoneum was left open during laparoscopic APR and propose that closure of the pelvic peritoneum should be routine in this operation.  相似文献   
79.
BACKGROUND: Chemokines are involved in leucocyte chemotaxis. Infiltrating leucocytes play an important role of tissue injury in systemic lupus erythematosus (SLE). OBJECTIVE: To investigate the role of inflammatory chemokines and their association with interleukin 18 (IL18) in SLE pathogenesis and disease activity. METHODS: Plasma concentrations and ex vivo peripheral blood mononuclear cell production of inflammatory chemokines IP-10, RANTES, MIG, MCP-1, TARC, IL8, and GROalpha, and proinflammatory cytokines IL18, IFNgamma, IL2, IL4, and IL10 were assayed in 80 SLE patients with or without renal disease and 40 healthy controls by immunofluorescence flow cytometry and enzyme linked immunosorbent assay. RESULTS: Plasma IP10, RANTES, MIG, MCP-1, GROalpha, and IL18 concentrations in all SLE patients were higher than in controls, and correlated significantly with SLEDAI score (all p<0.05). In SLE patients without renal disease, IP10, RANTES, MIG, MCP-1, IL8, and IL18 correlated positively with SLEDAI score, while in those with renal derangement, IP10, IL8, IL10, and IL18 correlated with disease activity (all p<0.05). Plasma IL18 concentration correlated positively with IP10, MIG, GROalpha, and IL8 in all SLE patients (all p<0.005). Mitogen induced increases in ex vivo production of IP10, MCP-1, TARC, IFNgamma, IL4, and IL10 were higher in all SLE patients regardless of their difference in disease activity (all p<0.05). Patients with renal disease had an augmented ex vivo release of RANTES. CONCLUSIONS: The correlation of raised plasma concentration and ex vivo production of inflammatory chemokines with disease activity, and their association with IL18, supports the view that chemotaxis of Th1/Th2 lymphocytes and neutrophils is important in SLE pathogenesis.  相似文献   
80.
The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large‐sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)‐positive chronic HBV infection (n = 588), HBeAg‐positive chronic hepatitis B (n = 596), and HBeAg‐negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (= .000), with the highest (4.60 log10 IU/mL [10%‐90% confidence interval: 3.52 log10 IU/mL‐4.99 log10 IU/mL]) in patients with HBeAg‐positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg‐positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg‐negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg‐positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg‐negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.  相似文献   
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