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81.
Hydrogen sulfide is formed by the subgingival microbiotas of periodontal pockets. The capacity of these microbiotas to form various volatile sulfur compounds in human serum was studied. Bacterial samples from nine deep periodontal pockets were incubated for 7 days in human serum and the amounts of volatile sulfur compounds and the degradation of serum proteins were determined. Hydrogen sulfide was the predominant volatile sulfur compound, but also methyl mercaptan was formed in significant amounts. Only traces of dimethyl sulfide and dimethyl disulfide were detected. There was an extensive degradation of the serum proteins. In most of the reaction mixtures hydrogen sulfide reached highly toxic levels.  相似文献   
82.
Microflora of the gallbladder related to duration of acute cholecystitis   总被引:4,自引:0,他引:4  
The microflora of the bile and wall of the gallbladder was prospectively investigated in 104 nonselected consecutive patients treated with early cholecystectomy for acute cholecystitis after an average hospital stay of 1.8 days. The chief purpose was to relate the findings of cultures to duration of the illness. Special attention was paid to anaerobic isolation techniques. The cultures yielded 107 strains, representing 36 species, with overall agreement between four different sampling procedures. Aerobic gram-negative rods predominated, followed by streptococci and anaerobes (48, 31 and 15 per cent, respectively). The incidence of positive culture results (always greater than or equal to 10(6) colon forming units per milliliter) was 81 per cent among the patients who underwent operation within two days from the onset of symptoms and 50 to 65 per cent after longer preoperative intervals. The shorter interval was significantly more often associated with growth solely of anaerobes (p = 0.03). Postoperative sepsis was caused by biliary bacteria and not related to preoperative duration of illness. Appropriate perioperative antibiotic coverage significantly reduced sepsis--3 versus 20 per cent (p = 0.05).  相似文献   
83.
In a prospective study aimed at determining the etiology of community-acquired pneumonia in children nasopharyngeal cultures and paired serum samples were obtained from 336 consecutive children ages 6 weeks to 15 years with pneumonia, 167 hospitalized and 169 outpatients. Results regarding Haemophilus influenzae are reported here. Blood cultures obtained from 127 of the hospitalized patients did not yield growth of H. influenzae. H. influenzae was isolated from the nasopharynx of 88 children. Seventy-three strains were noncapsulated, 2 were type b, 2 were type f and 11 were not serotyped. Paired serum samples were available from 38 children with growth of noncapsulated H. influenzae in the nasopharynx as the only potential pathogen. Sixteen of them responded with significant increases in serum antibodies against outer membrane preparations prepared from their own nasopharyngeal isolates. Thirty-eight age- and sex-matched control children with pneumonia without growth of H. influenzae in the nasopharynx served as controls. Sera from each control patient were tested for antibodies against two strains of noncapsulated H. influenzae. Of those, 4 had significant increases in antibodies against one or both outer membrane preparations. The increases in serum antibodies against the outer membrane of noncapsulated strains of H. influenzae indicate that this organism might be a cause of pneumonia in some children.  相似文献   
84.
Young severe combined immunodeficiency (scid) mice completely lack immunocompetent lymphocytes. Limiting numbers of purified CD4+ T cells from allotype-congenic BALB/c (Igha) donor mice were transplanted into 3-week-old scid (Ighb) recipient mice. Splenic CD4+ T cells were recovered from transplanted scid mice 10-12 weeks post-transfer and established as T cell lines in culture. These T cell populations proliferated in vitro in response to syngeneic stimulator cells. T cell clones derived in vitro from these T cell lines displayed selfreactive recognition specificity: these CD4+ T cells proliferated in vitro in response to syngeneic/congeneic but not allogeneic stimulator cells. Cloned selfreactive T cells retransplanted into young scid recipients were engrafted into spleens of secondary recipients, did not induce autoimmune disease but stimulated development of scid-derived (Ighb), IgM-producing B cells (B cell leakiness).  相似文献   
85.
Graft function and histology are predictive of renal transplant survival. The Rapamune Maintenance Regimen study demonstrated that early cyclosporine (CsA) withdrawal from a sirolimus (SRL)-CsA-steroid (ST) regimen improved renal function and blood pressure. We report the protocol-mandated biopsy findings from that study. Renal transplant patients (n = 430) receiving SRL-CsA-ST were randomized at 3 months after transplantation to remain on SRL-CsA-ST, or to have CsA withdrawn (SRL-ST group). Protocol-mandated biopsies were performed at engraftment and at 12 and 36 months. Two pathologists blindly evaluated 484 biopsies to obtain the Chronic Allograft Damage Index (CADI) scores. At 36 months among patients with serial biopsies (n = 63), the mean CADI score was significantly lower with SRL-ST(4.70 vs. 3.20, p = 0.003), as was the mean tubular atrophy score (0.77 vs. 0.32, p < 0.001). All six components of the CADI score were numerically lower in SRL-ST group; moreover, inflammation and the tubular atrophy scores decreased significantly in the SRL-ST group between 12 and 36 months. The calculated glomerular filtration rate at 36 months was significantly better in the CsA-withdrawal group (54.8 vs. 68.2 mL/min, p = 0.009). In conclusion, withdrawing CsA from the SRL-CsA-ST regimen resulted in improved renal histology and function.  相似文献   
86.
Interferon‐γ secreting T lymphocytes against pox virus‐derived synthetic 9‐mer peptides were tested by enzyme‐linked immunospot in peripheral blood of individuals vaccinated with vaccinia virus more than 30 years ago. The peptides were characterized biochemically as high‐affinity human leucocyte antigen (HLA) class I binders (KD ≤ 5 nM). However, five of the individuals tested did not show typical CD8+ T cell‐mediated HLA class I‐restricted responses. Instead, these donors showed CD4+ T cell‐dependent responses against four of a total of eight antigenic 9‐mer peptides discovered recently by our group. These latter responses were blocked specifically in the presence of anti‐HLA class II antibody. We conclude that long‐lived memory responses against pox virus‐derived 9‐mer peptides, with high binding affinity for HLA class I molecules, are mediated in some cases by CD4+ T cells and apparently restricted by HLA class II molecules.  相似文献   
87.
88.
To utilize the antibacterial effect of the lactoperoxidase system to prevent bacterial spoilage of raw milk it is necessary to increase the thiocyanate concentration of the milk. Thiocyanate has, however, a potent antithyroid effect which is enhanced by iodine deficiency. In this study the thyroid function has been studied, before and after 4 weeks daily administration of 250 ml of such treated milk, in 55 goitrous subjects living in an endemic goiter region of western Sudan. The iodine content was 0.1 mg/l and the thiocyanate content was either 3.6 mg/l (n 19) or 19 mg/l (n 36) in the milk. At the start of the experiment all subjects were iodine deficient with a urinary excretion of 40-50 micrograms/g creatinine. After 4 weeks daily intake of 4.75 mg of thiocyanate by way of milk the serum thiocyanate level increased by approximately 1.7 mg/l. Both at the beginning and at the end of the experimental period the serum levels of thyroxine, triiodothyronine and TSH were in the normal range for all subjects. After 4 weeks the TSH levels had decreased significantly, (from 2.6 +/- 0.2 to 2.1 +/- 0.2 mU/l, p less than 0.001) probably as an effect of the supplementary intake of iodine. The thyroid hormone levels remained unchanged during the experimental period. In conclusion, the intake of milk with an iodine concentration of 0.1 mg/l and a thiocyanate concentration of 19 mg/l does not have a negative effect on the thyroid function in iodine deficient subjects.  相似文献   
89.
In the presence of serum, 2-mercaptoethanol-treated bovine serum albumin enhances T cell colony formation as does 2-mercaptoethanol. The factor only partially substitutes for FCS, but neither for the mitogen phytohemagglutinin nor for conditioned medium derived from cultures of adherent cells.  相似文献   
90.
STUDY DESIGN: Cross-sectional study. OBJECTIVES: (1) To examine whether the Klein-Bell ADL Scale (K-B Scale) discriminates cervical spinal cord injury (SCI) patients in daily activities and to explore its applicability in this group of patients. (2) To examine the association between basic ADL and upper extremity function. (3) To investigate if grip ability can be discerned in the scale. SETTING: Spinal Cord Injury Unit, Sahlgrenska University Hospital, G?teborg, Sweden. METHODS: Fifty-five patients with cervical SCI with no prior reconstructive hand surgery were included in the study. Analyses of the patient's independence were made according to the K-B Scale. Three additional analyses were carried out, the first examined whether the use of assistive devices and house and car adaptations influenced independence. The last two used different approaches to investigate whether arm and grip function could be detected in the K-B scale. RESULTS: Raw score in the K-B Scale can discriminate for independence in daily activities but the scale's weight scheme does not function for cervical SCI patients. Assistive devices and car and house adaptations can compensate for dependence in daily activities. Lack of grip function decreases the patient's ability to become independent. Diagnosis-related activities cannot be assessed in all items. CONCLUSION: The K-B Scale's raw score was useful assessing daily activities in cervical SCI patients. Its reliability in conjunction with arm and grip function in patients with cervical SCI has yet to be proven.  相似文献   
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