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1.
To test the reported antipanic efficacy of clonazepam, the authors randomized 72 subjects with panic disorder to 6 weeks of treatment with either alprazolam, clonazepam, or placebo. Endpoint analysis demonstrated a significant beneficial effect of both active treatments, but not placebo treatment, on the frequency of panic attacks, overall phobia ratings, and the extent of disability. Comparison of the two active treatments revealed no significant differences and no consistent tendency for one agent to be favored over another, although power to detect small differences was limited. Sedation and ataxia were the most common side effects reported, but these effects were mild and transient and did not interfere with treatment outcome. The results of this double-blind, placebo-controlled trial are consistent with previous reports of clonazepam's antipanic efficacy.  相似文献   
2.
W S Updike  M Tesar  E Ehrenfeld 《Virology》1991,185(1):411-418
Hepatitis A virus (HAV) is distinguished from other picornaviruses by its tropism for the liver in infected hosts, a nonlytic infection in hepatocytes, and a slow and nonlytic growth cycle in cultured cells. Although the genome structure and organization of HAV appear to be similar to those of the other picornaviruses, the viral proteins synthesized in infected cells have not been previously characterized. We have utilized specific antisera raised in rabbits to recombinant HAV proteins expressed in Escherichia coli in an effort to identify both structural and nonstructural proteins in BS-C-1 cells throughout the course of a viral replication cycle. Replication was monitored by dot blot hybridization of viral genomes. Structural proteins VP0, VP1, VP2, and VP3 were found to accumulate during the infection cycle as did viral RNA. Nonstructural proteins 2C and 3D were not detected on immunoblots, although a minor amount of 2C could be detected by immunoprecipitation of lysates of radiolabeled, infected cells. The relative sensitivities of the various antisera were determined, and the failure to observe nonstructural proteins was shown not to be due to decreased sensitivity of the detection reagents. Thus, it appears that HAV nonstructural proteins do not accumulate in infected cells to levels comparable to those of capsid proteins.  相似文献   
3.
Cytokines and adhesion molecules in renal vasculitis and lupus nephritis   总被引:20,自引:1,他引:19  
Background: Plasma levels of some pro-inflammatory cytokines and soluble adhesion molecules have been suggested to be useful parameters to assess the activity of antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis and lupus nephritis. We hypothesized that the renal activity of these diseases is better reflected by the urinary excretion and fractional excretion of these molecules. Methods: Plasma levels and urinary excretion of tumour necrosis factor-&agr; (TNF-&agr;), interleukin (IL)-6, IL-8, and the soluble cell adhesion molecules sICAM-1 and sVCAM-1 were measured by enzyme-linked immunosorbent assay (ELISA) in 15 patients with ANCA-positive renal vasculitis (eight active, ANCA-A; six in remission, ANCA-R), six patients with active lupus nephritis (LN), 15 patients with IgA nephropathy (IgAN) and nine healthy subjects. Fractional excretion of selected cytokines and adhesion molecules was also calculated. Results: Patients with ANCA-A had increased urinary excretion and fractional excretion of TNF-&agr; (9.27±3.19% vs 0.58±0.02%, P<0.01), IL-6 (120.79±65.83% vs 1.89±0.34%, P<0.01) and increased fractional excretion of IL-8 (23.34±6.38% vs 2.56±1.07%, P<0.01) and sVCAM-1 (0.81±0.33% vs 0.03±0.02%, P<0.01) compared with controls. Urinary excretion of TNF-&agr; and IL-6 and fractional excretion of TNF-&agr;, IL-6 and IL-8 were higher in ANCA-A than in ANCA-R. Patients with LN had increased plasma TNF-&agr; (20.52±2.01 pg/ml vs 12.33±0.23 pg/ml, P<0.05) and sVCAM-1 (1537.88±276.36 ng/ml vs 692.26±44.42 ng/ml, P<0.05) and increased urinary excretion of TNF-&agr; (2.81±0.51 &mgr;g/mol creat vs 0.98±0.05 &mgr;g/mol creat, P<0.01), IL-8 (35.78±14.03 &mgr;g/mol creat vs 12.46±5.19 &mgr;g/mol creat, P<0.05) and sVCAM-1 (48.98±20.20 &mgr;g/mol creat vs 2.92±1.35 &mgr;g/mol creat, P<0.01) compared with controls. Patients with IgAN had, in comparison with controls only increased plasma TNF-&agr; (18.10±0.57 pg/ml vs 12.33±0.23 pg/ml, P<0.05). Conclusions: Urinary excretion and fractional excretion, but not plasma levels of selected proinflammatory cytokines (TNF-&agr;, IL-6 and IL-8) were increased in patients with active ANCA-positive renal vasculitis, but not in ANCA positive vasculitis in remission. These parameters may be useful to monitor the activity of this disease.  相似文献   
4.
Sudan staining of gross specimens with correlated histologic sections was used to localize the accumulation of fat in the aortas of genetically susceptible and resistant strains of pigeons. The birds were maintained on a cholesterol-free grain diet, and studies were done sequentially from ages 1 month to 4 years. Evidence suggests that the accumulation of lipids in musculoelastic cushions located at the origin of small branches is not necessarily a precursor of complicated lesions, but that it occurs concurrently in susceptible and resistant strains. In contrast, in the "lesion area," lipid accumulation is more striking and occurs earlier in the susceptible strain. It precedes proliferation by three to six months. Thus, in this model, two distinct types of fatty streaks can be identified and their biologic features can be defined and related to their propensity for atherogenesis.  相似文献   
5.
Identification of critical quality attributes (CQAs) is an important step for development of biopharmaceuticals with intended performance. An accurate CQA assessment is needed to ensure product quality and focusing on development efforts where control is needed. The assignment of criticality is based on safety and efficacy. Efficacy is related to PK and bioactivity. Here, we developed a novel approach based on antibody-antigen complex structure and modeling as a complementary method for bioactivity assessment. To validate this approach, common product related quality attributes and mutagenesis data from several IgGs were assessed using available antibody-antigen complex structures, and results were compared with experimental data from bioactivity or binding affinity measurements. A stepwise evaluation scheme for structural based analysis is proposed; based on systematic assessment following the scheme, good correlation has been observed between structural analysis and experimental data. This demonstrates that such an approach can be applied as a complementary tool for bioactivity assessment. Main applications are 1) To decouple multiple attributes to achieve amino acid resolution for bioactivity assessment, 2) To assess bioactivity of attributes that cannot be experimentally generated, 3) To provide molecular mechanism for experimental observation and understand structure function relationship. Examples are provided to illustrate these applications.  相似文献   
6.
Plasma exchange (PE) is an effective therapeutic method used in patients with myasthenia gravis (MG) refractory to common therapy and/or with life-threatening respiratory complications. Except for acetylcholine receptor antibodies (AChRAbs), some other inflammatory mediators possibly activated in MG may also be removed during PE. Serum levels of soluble adhesion molecules (sICAM-1 and sVCAM-1), IL-6 and soluble receptors for IL-2 (sIL-2R), IL-6 (sIL-6R) and TNF alpha (sTNF-R II) were measured in 20 MG patients assigned to treatment with PE. On the basis of the serum levels of AChRAb the patients were subdivided into 2 groups (8 patients with low AChRAb, 12 patients with high AChRAb). Soluble adhesion molecules and cytokines were measured before the first and last PE, at the end of the first PE and in the samples of plasma filtrate obtained during the first PE. Before the first PE patients with MG had higher serum levels of sICAM-1, sVCAM-1, sIL-2R and sTNF-R II than controls. Both after the first PE and during the course of PE, a substantial decrease in serum levels of AChRAb, sICAM-1 and sVCAM-1 was recorded. However, serum levels of sIL-2R and sTNF-R II were not significantly influenced by either a single treatment or during the course of PE. There were high levels of AChRAb, soluble adhesion molecules and soluble cytokine receptors in plasma filtrates too. Patients with high circulating AChRAb had higher serum levels of sICAM-1 and sVCAM-1 than patients with low AChRAb. Increased serum levels of soluble adhesion molecules and soluble cytokine receptors in patients with MG suggest some systemic activation of the immune response which is more pronounced in patients with high circulating AChRAb. PE led to the decrease in serum AChRAb and soluble adhesion molecules due to their effective filtration but, on the other hand, serum levels of soluble cytokine receptors were not influenced by PE, in spite of their effective filtration which is probably counteracted by their increased production, possibly stimulated by the contact of the blood with the synthetic membrane.  相似文献   
7.
OBJECTIVE: The radiographic diagnosis of osteoarthritis (OA) in the peripheral skeleton is dependent on the skilled examination of several morphological characteristics of the condition as visualised on plain radiographs. However, the process is perceptual and generally enhanced by comparison against photographic standards. This study assessed the intra-rater and inter-rater reliability of radiologists experienced in reporting hand, hip and knee films derived from a community-based sample when using the photographic atlas recently developed by Burnett et al. METHODS: This study was part of a multifaceted diagnostics protocol, evaluating methodological issues, in the conduct of genetic research in osteoarthritis. From a cohort of 118 twin pairs, registered with the Australian Twins Registry (ATR), standard clinical examinations were performed on 74 complete and 11 incomplete pairs of twins over age 50 years, followed by standard AP hand, AP pelvis and AP standing radiographs of the knees. The pairs were selected both to represent twin pairs who had previously self reported a diagnosis of OA, as well as those who had not. Radiologists read the films blind to the original self reported diagnosis and without reference to their pairing. The films were read by comparison against photographic standards and were scored according to specific features. All films were read independently by two consultant radiologists blind to one another's assessments, and selected films were thereafter assigned for rereading. Inter-rater and intra-rater agreement were different for different features, different anatomic areas, and, for the former, were different for the two radiologists. RESULTS: Inter-rater agreement was different for different anatomic areas, different radiographic features, and the two radiologists. Intra-rater agreement for the presence or absence of OA was as follows: actual observed agreement = 0.79 to 0.97 and 0.83 to 0.98; adjusted kappa statistic = 0.58 to 0.94 and 0.67 to 0.96; inter-rater agreement was as follows: actual observed agreement = 0. 77 to 0.97; adjusted kappa statistic = 0.54 to 0.94. Agreement was generally high in most of the principal target joints for OA: DIP, PIP, 1st CMC, hip and knee. CONCLUSIONS: Although assessor agreement was not perfect, it is concluded that for genetic epidemiology purposes, while duplicate assessments may be advantageous, it is possible for radiographs to be examined accurately by a single experienced assessor. However, for less experienced assessors independent examinations should be made by at least two assessors and either a consensus reached on disparate examinations or an algorithm developed to adjudicate any discrepancies.  相似文献   
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BACKGROUND: The response of hepatocellular carcinoma (HCC) to therapy is often disappointing and new modalities of treatment are clearly needed. Active immunotherapy based on the injection of autologous dendritic cells (DC) co-cultured ex vivo with tumor antigens has been used in pilot studies in various malignancies such as melanoma and lymphoma with encouraging results. METHODS: In the present paper, the preparation and exposure of patient DC to autologous HCC antigens and re-injection in an attempt to elicit antitumor immune responses are described. RESULTS: Therapy was given to two patients, one with hepatitis C and one with hepatitis B, who had large, multiple HCC and for whom no other therapy was available. No significant side-effects were observed. The clinical course was unchanged in one patient, who died a few months later. The other patient, whose initial prognosis was considered poor, is still alive and well more than 3 years later with evidence of slowing of tumor growth based on organ imaging. CONCLUSIONS: It is concluded that HCC may be a malignancy worthy of DC trials and sufficient details in the present paper are given for the protocol to be copied or modified.  相似文献   
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