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21.
Group I Burkitt lymphoma (BL) cell lines, which retain the original biopsy phenotype, have been shown to enter apoptosis in response to a number of external stimuli including serum deprivation, thermal shock, addition of calcium ionophore, and ligation of surface immunoglobulin (Ig) by antibody. Transforming growth factor-beta 1 (TGF beta 1) is known to cause growth arrest in BL lines. Here we show that while it is by itself capable of promoting some degree of apoptosis in group IBL cells, TGF beta 1 cooperates with anti-immunoglobulin to this end. Trimeric soluble recombinant human CD40 ligand (sCD40L) was able to inhibit apoptosis induced by the combination of agonists to some degree, but such rescue proved to be short-lived. Both TGF beta 1 and anti-Ig individually caused BL cells to undergo growth arrest at the G1 phase of cell cycle before their entry into apoptosis: the consequence of sCD40L addition was to maintain the cells in cycle for longer. No induction of the apoptosis-protecting gene, bcl-2, occurred in the presence of sCD40L. These findings are discussed, particularly highlighting the relationship existing between survival and the cell cycle. The strong cooperative effects observed between anti-Ig and TGF beta 1 in promoting apoptosis and the inability of CD40 to signal for long-term rescue raise the potential for a novel therapeutic attack on B-cell lymphoma.  相似文献   
22.
Moderation of hemophilia A phenotype by the factor V R506Q mutation   总被引:11,自引:1,他引:11  
Although many examples of unrelated hemophilia A patients carrying identical point mutations in the factor VIII (FVIII) gene have been reported, the clinical phenotype is not always the same among patients sharing the same molecular defect. Possible explanations for this discrepancy include undetected additional mutations in the FVIII gene or coinheritance of mutations at other genetic loci that modulate FVIII function. We report molecular genetic analysis of potential modifying genes in two sets of unrelated patients carrying common FVIII missense mutations but exhibiting different levels of clinical severity. Both mutations (FVIII R1689C and R2209Q) are associated with severe hemophilia A in some patients and mild/moderate disease in others. The common von Willebrand disease type 2N mutation (R91Q) was excluded as a modifying factor in these groups of patients. However, analysis of the recently described factor V (FV) R506Q mutation (leading to activated protein C resistance) identified a correlation of inheritance of this defect with reduced hemophilia A severity. Two moderately affected hemophilia A patients, each with either of two FVIII gene mutations, were heterozygous for FV R506Q, whereas two severely affected patients and two moderately affected patients were homozygous normal at the FV locus. Our results suggest that coinheritance of the FV R506Q mutation may be an important determinant of clinical phenotype in hemophilia A and that modification of the protein C pathway may offer a new strategy for the treatment of FVIII deficiency.  相似文献   
23.
Chan  WC; Link  S; Mawle  A; Check  I; Brynes  RK; Winton  EF 《Blood》1986,68(5):1142-1153
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA.  相似文献   
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Immunolocalisation of androgen receptor (AR) and steroid contents were analyzed in the ovaries of 7- and 14-day-old bank voles, reared in a long (LD) and short (SD) photoperiod. The strongest AR immunoreaction was found in the stromal cells, especially in the ovaries of 7-day-old animals, and in the granulosa cells of all types of ovarian follicles. Oocytes and the cells of surface epithelium were AR positive. The amount of ovarian androgens was relatively high, whereas the level of estradiol was negligible. This finding, and the presence of numerous ARs in various ovarian compartments, suggest that aromatization was very low during development and the primary function of androgens was hormonal action via a receptor-mediated pathway. Age- and photoperiod-related differences in ovarian progesterone (P4) levels were higher in animals kept in LD than in SD, rising significantly on day 14. Androgen content tended to be lower in LD voles and slightly decreased on day 14. Photoperiod-related differences concerning AR immunolabeling were apparent only in 14-day-old animals. In LD, ovaries already possessed early antral follicles, showing strong AR immunolabeling in the cumulus cells. Immunoreaction of 3β-hydroxysteroid dehydrogenase (3β-HSD) showed that the primary interstitial and theca cells were the first to be active in ovarian steroidogenesis. In conclusion, AR is present in juvenile vole ovaries as early as day 7. The influence of the photoperiod on their number is observed beginning on day 14. Differences in steroid contents due to LD conditions occur in 7-day-old, and progresses in 14-day-old animals.  相似文献   
27.
Data comparing the treatment outcomes of the two most frequently recommended empirical antibiotic regimens for community-acquired pneumonia (CAP)--combination therapy with an extended-spectrum beta-lactam and a macrolide (BL+M) or fluoroquinolone (F) monotherapy--for patients with severe CAP are sparse. The purpose of this study was to compare empirical BL+M combination therapy with F monotherapy for Veterans Affairs (VA) patients with severe CAP. This retrospective study included patients with CAP who received empirical therapy with BL+M or F between October 1999 and May 2003 in the Upstate New York VA Network. Outcome measures were 14-day mortality, 30-day mortality, and length of hospital stay (LOS). Severe CAP was defined as a class V pneumonia severity index (PSI). During the study period, 261 patients received BL+M and 254 received F. Disease severity was similar for the two treatment groups at admission, and the presence of tachycardia was the only difference noted. For PSI class V patients, there were lower 14-day and 30-day mortality rates with BL+M than with F (14-day rates, 8.2% versus 26.8% [P = 0.02]; 30-day rates, 18.4% versus 36.6% [P = 0.05]). No differences in mortality between treatment groups were noted for the lower PSI classes. The overall median LOS was significantly longer for the BL+M combination group than for the F monotherapy group (6.0 days versus 5.0 days, respectively [P = 0.01]), but no difference in LOS was noted among PSI class V patients. Our study showed that improved outcomes may be realized with BL+M in cases of severe CAP. A randomized clinical study is warranted based on these results.  相似文献   
28.
The treatment of burn wounds by enzymatic debridement using bromelain has shown promising results in our burn center. However, inadequate debridement occurred in a few cases in which the etiology of the burn was attributed to relatively low temperature burns. We hypothesized that bromelain is ineffective in burns in which collagen denaturation, which occurs approximately at 65°C, has not taken place. Our objective was to assess whether there is a relationship between the denaturation of collagen and the ability of bromelain to debride acute scald burn wounds of different temperatures. Ex vivo human skin from four different donors was cut into 1x1 cm samples, and scald burns were produced by immersion in water at temperatures of 40°C, 50°C, 60°C, 70°C, and 100°C for 20 minutes. Denaturation of collagen was assessed with histology, using hematoxylin and eosin (H&E) staining and a fluorescently labeled collagen hybridizing peptide (CHP), and with second harmonic generation (SHG) microscopy. Burned samples and one control sample (room temperature) were weighed before and after application of enzymatic debridement to assess the efficacy of enzymatic debridement. After enzymatic debridement, a weight reduction of 80% was seen in the samples heated to 70°C and 100°C, whereas the other samples showed a reduction of 20%. Unfolding of collagen, loss of basket‐weave arrangement, and necrosis was seen in samples heated to 60°C or higher. Evident CHP fluorescence, indicative of collagen denaturation, was seen in samples of 60°C, 70°C and 100°C. SHG intensity, signifying intact collagen, was significantly lower in the 70°C and 100°C group (P <.05) compared to the lower temperatures. In conclusion, denaturation of collagen in skin samples occurred between 60°C and 70°C and strongly correlated with the efficacy of enzymatic debridement. Therefore, enzymatic debridement with the use of bromelain is ineffective in scald burns lower than 60°C.  相似文献   
29.

Background

Ovarian cancer arising in women with BRCA mutations is known to have a more favorable outcome and to be more responsive to platinum-based regimens than in those without a hereditary background. We analyze our previously published intraperitoneal (IP) studies in relation to BRCA mutation status and update their outcomes.

Methods

Among 62 patients with ovarian cancer enrolled in IP platinum doublet studies in clinical trials (with etoposide (n = 18), with floxuridine (n = 30), and with topotecan (n = 14)), a deleterious BRCA mutation was eventually identified in 10 patients. The outcomes in these BRCA mutation carriers are described and compared with survival of others in respective trials.

Results

Ten patients that were confirmed to have BRCA mutations—all with high-grade and stages IIC to IV disease—survived a median of 10 years (range: 4–18+) after receiving IP cisplatin-based regimens. Two continue with no evidence of disease since their IP treatment, while four others remain alive with recurrences after 8, 9, 10, and 11 years, respectively.

Conclusions

This experience suggests that IP cisplatin leads to favorable long term outcomes in advanced ovarian cancer in women with defective homologous recombination (i.e., with deleterious BRCA mutations). Whether such cisplatin dose-intensification from IP relative to (intravenous) IV drug administration leads to superior results in these mutation carriers requires further study.  相似文献   
30.
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