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21.
Metabolic Brain Disease - mTOR has been shown to be involved in the regulation of immune responses and differentiation of immune cells. This protein is a candidate molecule for unraveling the...  相似文献   
22.
Gastrointestinal hemorrhage in children is a critical condition that demands quick and effective management. The differential diagnosis of gastrointestinal hemorrhage is wide. Heterotopic pancreas is a rare congenital anomaly and usually discovered incidentally. It is generally asymptomatic, but symptoms may occur when complicated by inflammation, bleeding, obstruction or malign transformation. Heterotopic pancreas may present throughout the gastrointestinal tract, but it is most commonly found in the stomach, duodenum and proximal jejunum. Juvenile polyps are common during childhood and present most often with painless rectal hemorrhage. They remain the most common colonic polyps in children. Colonoscopic polypectomy is the most effective procedure in the treatment of juvenile polyps. In this study, we describe rare causes of gastrointestinal system hemorrhage in infancy and discuss some diagnostic and therapeutic approaches.  相似文献   
23.
Hyperviscosity syndrome (HVS) develops most commonly in Waldenström's macroglobulinemia (WM) and multiple myeloma (MM). Plasmapheresis is the immediate therapy and very effective at relieving symptoms by removing paraprotein. The most commonly used replacement fluid is 4%–5% human albumin in physiologic saline. FFP may be used in patients with coagulation abnormalities. Plasmapheresis should be continued until acute symptoms abate. Hyperviscosity impairs the circulation in the retina and causes hemorrhages around the small retinal vessels. Early diagnosis and urgent plasmapheresis may reduce blindness caused by retinal hemorrhages and/or retinal detachment. In HCV related mixed cryoglobulinemias, plasmapheresis is indicated if rapidly evolving life-threatening disease with immunosuppressive agent exists. In non-infectious mixed cryoglobulinemia plasmapheresis is indicated when the disease manifestations are severe, as a second line option. In WM patients with hyperviscosity symptoms and IgM?>?4?g/dL, preemptive plasmapheresis is recommended to prevent an IgM flare with rituximab. Certain IgG/A MGUS-associated neuropathy patients may benefit from plasmapheresis. For cast nephropathy (suspected or biopsy proven), plasmapheresis is recommended when the sFLC?≥?500?mg/l and as early as possible (<1 month with kidney injury). Theoretically, extracorporeal removal alone, without efficient tumor killing, could not reduce sFLC due to high production by the tumor mass and rapid rebound between compartments.  相似文献   
24.

Objectives

Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern.

Methods

UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded.

Results

Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients'' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers.

Conclusion

This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients'' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.  相似文献   
25.
Folayan  Morenike Oluwatoyin  Ibigbami  Olanrewaju  Brown  Brandon  El Tantawi  Maha  Uzochukwu  Benjamin  Ezechi  Oliver C.  Aly  Nourhan M.  Abeldaño  Giuliana Florencia  Ara  Eshrat  Ayanore  Martin Amogre  Ayoola  Oluwagbemiga O.  Osamika  Bamidele Emmanuel  Ellakany  Passent  Gaffar  Balgis  Idigbe  Ifeoma  Ishabiyi  Anthonia Omotola  Jafer  Mohammed  Khan  Abeedha Tu-Allah  Khalid  Zumama  Lawal  Folake Barakat  Lusher  Joanne  Nzimande  Ntombifuthi P.  Popoola  Bamidele Olubukola  Quadri  Mir Faeq Ali  Rashwan  Maher  Roque  Mark  Shamala  Anas  Al-Tammemi  Ala’a B.  Yousaf  Muhammad Abrar  Abeldaño Zuñiga  Roberto Ariel  Okeibunor  Joseph Chukwudi  Nguyen  Annie Lu 《AIDS and behavior》2022,26(3):739-751
AIDS and Behavior - The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living...  相似文献   
26.
BACKGROUND: Most current guidelines state that antiretroviral therapy should be considered for HIV-infected patients with plasma HIV RNA > 5000-10000 copies/ml and CD4 cells > 500 x 10(6) cells/l. However, there is increasing concern about whether this is the optimal point to begin treatment or whether it is better to delay the initiation to more advanced stages. OBJECTIVE: To study the immunological and virological benefits of starting antiretroviral therapy at these early stages. METHODS: A total of 161 HIV-infected asymptomatic patients with CD4 cell count > 500 x 10(6) cells/l and viral load > 10000 copies/ml were randomly assigned to one of five treatment groups: no treatment, twice daily zidovudine and thrice daily zalcitabine (ZDV-ddC), twice daily zidovudine and didanosine (ZDV-ddI), twice daily stavudine and didanosine (D4T-ddI), or a twice daily three-drug regimen with stavudine and lamivudine and ritonavir. The endpoints were progression to < 350 x 10(6) cells/l CD4 cells, to < 500 x 10(6) cells/l with either two Centers for Disease Control class B symptoms or an increase of viral load > 0.5 log10 copies/ml above baseline, or to AIDS or death. In various substudies, the lymphoid tissue and cerebrospinal fluid viral load, development of genotypic resistance, proliferative responses to mitogens and cytomegalovirus, and HIV-1 specific antigens and other immunophenotypic markers were also analysed. RESULTS: Progression rates to study endpoints within 1 year were greater in the control group (31%) than in all groups receiving antiretroviral therapy pooled together (5%; estimated hazard ratio 7.41; 95% confidence interval 5.72-74.55; P < 0.001). The peak mean viral load decrease was greater in the three-drug group when compared with any of the three groups with a two-drug regimen (2.32, 1.65, 1.72 and 1.84, respectively; P < or = 0.001). At 1 year, viral load remained below 20 copies/ml in 30 out of 33 patients in the three-drug group (91%) and in only eight out of 94 patients (9%) in two-drug groups (P = 0.001). The peak mean increase in CD4 cells was also greater in the three-drug group than in the double treatment arms (259 versus 85, 144 and 145 x 10(6) cells/l, respectively; P = 0.001). By comparison, 36% of patients in the three-drug group regimen had to change the therapy as a result of adverse events. Substudies were performed in 60 patients recruited at two sites. Tonsillar tissue HIV RNA was measured in seven patients (two in the two-drug groups and five in the three-drug group) in whom plasma HIV RNA was < 20 copies/ml at 1 year. It was 15151 and 133333 copies/mg tissue in the two patients from the two-drug group, < 40 copies/mg tissue in four patients in the three-drug group, and 485 copies/mg in one patient in the three-drug group. At 1 year there was a mean increase of 4.21+/-2.94% in CD8+CD38+ cells in the control group and a decrease of 9.48+/-3.36% in the two-drug groups (P = 0.01), and 19.87+/-3.64 in the three-drug group (P = 0.001 and P = 0.05, for comparisons with control group and two-drug groups, respectively). Although proliferative responses to cytomegalovirus antigens were significantly greater in those receiving antiretroviral therapy, response to HIV-1 p24 antigen was not detected in any patient in either treatment group. CONCLUSIONS: This study supports the recommendation to start antiretroviral therapy with a three-drug combination during very early stages of HIV-1 disease, at least if viral load is above a cut-off point (10000 copies/ml in our study). The risk of progression was sevenfold higher in non-treated patients at 8 months of follow-up. Some immune system parameters improved toward normal values after 1 year of antiretroviral therapy, but the proliferative response of CD4 T lymphocytes against the p24 HIV-1 antigen was not recovered. Therapeutic approaches with more potent, better-tolerated and more convenient regimens will increasingly favour early intervention with antiretroviral t  相似文献   
27.
28.
Multiple myeloma (MM) is associated with amyloidosis in approximately 15% of the patients. The most frequent presenting signs of such an association are nephrotic syndrome, cardiomyopathy and peripheral neuropathy. Amyloid arthropathy is not a frequent feature. We report a patient with immunoglobulin D (IgD) lambda type MM with presenting symptoms related to mucocutaneous amyloidosis and also amyloid arthropathy. He had no clinical and laboratory involvement due to nephrotic syndrome or cardiomyopathy. IgD myeloma is a rare form of MM and therefore much of the information about the disease is derived from case reports describing patients with associated symptoms. Our case also shows an unusual organ distribution of amyloid.  相似文献   
29.
OBJECTIVE: To investigate the molecular and biochemical profile of skeletal muscle mitochondria of patients with isolated polymyalgia rheumatica (PMR). PATIENTS AND METHODS: We included patients with a recent diagnosis of PMR and as control healthy individuals submitted to orthopedic surgery. Skeletal muscle was obtained from quadriceps, thus was mitochondria immediately isolated. Long polymerase chain reaction and Southern blot transference were performed to detect deleted mtDNA molecules. Mitochondrial oxidative activity using different substrates and individual enzyme activity of respiratory chain complexes were assessed to search for any biochemical dysfunction. RESULTS: Fifty-one individuals (PMR=25, controls=26) were included. Mean age was 72 (11) years; 45% were females. We found no significant increase of deleted mtDNA molecules in PMR patients compared to controls. Both groups differed neither on oxygen consumption (p=NS for all substrates) nor enzymatic activity (p=NS for all complexes). CONCLUSIONS: Skeletal muscle mitochondria are molecularly and biochemically unaffected in PMR.  相似文献   
30.
ObjectivesTo compare the characteristics of patients undergoing treatment with continuous intestinal infusion of levodopa-carbidopa (CIILC) for advanced Parkinson's disease and the data on the effectiveness and safety of CIILC in the different autonomous communities (AC) of Spain.MethodsA retrospective, longitudinal, observational study was carried out into 177 patients from 11 CAs who underwent CIILC between January 2006 and December 2011. We analysed data on patients’ clinical and demographic characteristics, variables related to effectiveness (changes in off time/on time with or without disabling dyskinesia; changes in Hoehn and Yahr scale and Unified Parkinson's Disease Rating Scale scores; non-motor symptoms; and Clinical Global Impression scale scores) and safety (adverse events), and the rate of CIILC discontinuation.ResultsSignificant differences were observed between CAs for several baseline variables: duration of disease progression prior to CIILC onset, off time (34.9-59.7%) and on time (2.6-48.0%; with or without disabling dyskinesia), Hoehn and Yahr score during on time, Unified Parkinson's Disease Rating Scale-III score during both on and off time, presence of ≥ 4 motor symptoms, and CIILC dose. Significant differences were observed during follow-up (> 24 months in 9 of the 11 CAs studied) for the percentage of off time and on time without disabling dyskinesia, adverse events frequency, and Clinical Global Impression scores. The rate of CIILC discontinuation was between 20-40% in 9 CAs (78 and 80% in remaining 2 CAs).ConclusionsThis study reveals a marked variability between CAs in terms of patient selection and CIILC safety and effectiveness. These results may have been influenced by patients’ baseline characteristics, the availability of multidisciplinary teams, and clinical experience.  相似文献   
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