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排序方式: 共有480条查询结果,搜索用时 31 毫秒
101.
Background
Studies show that tuberculosis notification declines with increasing altitude. This can be due to declining incidence or declining case detection. In Vietnam notification rates of new smear-positive tuberculosis in the central mountainous provinces (26/100,000 population) are considerably lower than in Vietnam in general (69/100,000 population). In order to clarify whether this is explained by low incidence or low case detection, we aimed to assess the prevalence of new smear-positive tuberculosis among adults with prolonged cough in three mountainous provinces in central Vietnam. 相似文献102.
Humphrey RW; O'Brien TR; Newcomb FM; Nishihara H; Wyvill KM; Ramos GA; Saville MW; Goedert JJ; Straus SE; Yarchoan R 《Blood》1996,88(1):297-301
Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed. 相似文献
103.
Masood R; Zhang Y; Bond MW; Scadden DT; Moudgil T; Law RE; Kaplan MH; Jung B; Espina BM; Lunardi-Iskandar Y 《Blood》1995,85(12):3423-3430
Interleukin-10 (IL-10) is an acid-sensitive protein of 35 kD that has pleiotropic effects including inhibition of cytotoxic T-cell response, induction of major histocompatibility complex type II in B lymphocytes, induction of B-cell growth and differentiation, and autocrine growth factor activity in monocytes. We and others have shown that IL-10 is produced spontaneously by blood mononuclear cells from human immunodeficiency virus-seropositive patients. In an attempt to ascertain the potential role of IL-10 in acquired immunodeficiency syndrome (AIDS)-related B-cell lymphoma, we evaluated the expression of human IL-10 in both tumor-derived B-cell lines and primary tumor cells. Expression of human IL-10 (hIL-10) mRNA and protein was detected in four of five cell lines examined. An IL-10 antisense oligonucleotide inhibited IL-10 mRNA expression and IL-10 protein production. The proliferation of all B-cell lines was inhibited by an antisense oligonucleotide in a dose-dependent manner that was abrogated by the addition of recombinant hIL-10 protein. No effect of antisense oligonucleotide was observed in the B-cell line not producing hIL-10. Evaluation of primary tumor cells from patients with AIDS-lymphoma cells showed similar production and response to IL-10. These data suggest an autocrine growth mechanism for IL-10 in AIDS-related lymphoma cells and that IL-10 may be important in its pathogenesis. 相似文献
104.
Urba WJ; Baseler MW; Kopp WC; Steis RG; Clark JW; Smith JW d; Coggin DL; Longo DL 《Blood》1989,73(1):38-46
Immune function in patients with hairy cell leukemia (HCL) was examined serially during treatment with alternating monthly cycles of recombinant interferon alpha-2a and 2'-deoxycoformycin (dCF). At presentation, most patients had normal numbers of T lymphocytes and their cells had normal proliferative responses to mitogens [phytohemagglutinin (PHA) and concanavalin A (Con A)] and alloantigens. Patients had severe monocytopenia, decreased delayed-type hypersensitivity (DTH) reactions, and decreased peripheral blood natural killer (NK) activity. Treatment caused a profound decrease in all lymphocyte subpopulations. T cells were more affected than B cells or NK cells. Numbers of CD4+ and CD8+ lymphocytes decreased to levels less than 200 cells/microliters in all patients during treatment. This decrease in T cell number was associated with a marked decrease in proliferative responsiveness to PHA, Con A, and alloantigens. These abnormalities persisted throughout the 14 months of treatment and have continued for up to 6 months beyond discontinuation of treatment. NK cell activity increased during treatment, but cycled depending on the phase of treatment; highest activities were observed after interferon (IFN)-alpha and lower levels of activity were observed after dCF. DTH responses generally did not improve during therapy. Levels of IgM, IgG, IgA, and IgD did not change during treatment, but IgE levels rose in most patients. All immunosuppressive effects were attributable to dCF since patients receiving IFN-alpha 2a alone did not exhibit these same immunosuppressive effects, and patients receiving dCF alone after IFN failure exhibited similar abnormalities. Despite this severe immunosuppression from dCF, life-threatening opportunistic infections have not been observed in our patient population. Six patients developed localized Herpes zoster infection among 21 patients who had received dCF. Pending the results of long-term follow-up, we recommend that dCF be reserved for patients who have failed splenectomy and IFN therapy. 相似文献
105.
We have previously observed an increased frequency of liver failure in human immunodeficiency virus (HIV)-infected hemophiliacs. The purpose of this study was to quantitate hepatitis C virus (HCV) RNA levels in serial samples from HIV-seropositive (HIV+) and HIV-seronegative (HIV-) hemophiliacs before and after HIV seroconversion, and to examine the relationship of HCV RNA levels to CD4 cell counts and to hepatic dysfunction over time. HCV RNA levels were measured on serial samples of serum stored frozen from 17 HCV+/HIV+ and 17 HCV+/HIV- subjects matched within 5 years of their birth dates. All were HCV+ before study entry. HCV RNA levels were quantitated by a branched DNA-enhanced label amplification (bDNA) assay. For samples less than the cut off, HCV RNA was measured by the nested polymerase chain reaction. Individual changes over time, clinical groups, and mean values within predetermined time windows were compared with Wilcoxon rank sum tests. Mean HCV RNA levels increased from 2.76 (standard error [SE] 1.33) x 10(5) to 2.84 (SE 1.39) x 10(6) eq/mL during the first 2 years after HIV seroconversion (P = .006). Baseline HCV RNA levels in the pre-HIV seroconversion group were not significantly different from the baseline levels in those who remained HIV (P = .79). Over the entire period of study, HCV RNA levels increased nearly threefold in those who remained HIV- (mean 9.47 [SE 4.78] x 10(5) to 2.81 [SE 1.13] x 10(6)/mL; P = .02). Among those who became HIV+, HCV RNA levels increased 58-fold (mean 2.85 [SE 1.26] x 10(5) to 1.66 [SE 0.57] x 10(7) eq/mL; P = .0001). The rate of increase in HCV RNA levels was eightfold faster for HIV+ subjects than for subjects who remained HIV- (P = .009). HCV RNA levels increased twofold higher in 5 subjects who developed liver failure compared with the 12 who did not (P = .43). HCV RNA levels correlated significantly with CD4 counts (R = -.33, P = .01) and serum aspartate aminotransferase levels (AST) (R = .36, P = .007). We conclude that HCV RNA levels are significantly higher in HIV+ than in HIV- multitransfused hemophiliacs. HCV load increases over time, is enhanced by HIV, and further increases as immune deficiency progresses. HCV RNA levels are directly associated with high AST levels. These findings suggest that HIV-induced immune deficiency may promote increased HCV replication. 相似文献
106.
107.
Studies on the structure of bovine factor V by scanning transmission electron microscopy 总被引:2,自引:0,他引:2
We studied purified bovine factor V (mol wt 330,000) by scanning transmission electron microscopy (STEM) of freeze-dried unstained or negatively contrasted preparations. Freeze-dried molecules revealed discrete shapes ranging from roughly spheroidal (100 to 120 nm) to oblong (140 to 200 nm in length X 50 to 100 nm in width). Oblong shapes could often be resolved into two or three distinct domains, ranging from 60 to 100 nm in diameter. A "satellite" nodular structure (30 to 50 nm in diameter) connected to the main molecule by a thin stalk (approximately 10 nm wide) up to 80 nm in length was occasionally seen. Glutaraldehyde-treated preparations yielded the same shapes as were seen in unfixed preparations but revealed better definition of submolecular features and "satellite" nodules. STEM mass analysis confirmed that each of the different shapes represented a monomolecular form of factor V. Negatively stained images revealed objects having the same general shapes as freeze-dried molecules, although greater detail was evident. Some images suggested that molecules consist of five or more discrete parts. Taken together, these observations indicate that factor V molecules are multidomainal, flexible structures that tend to have an irregular oblong shape with an axial ratio between 3:2 and 2:1. 相似文献
108.
Bone mineral density at distal forearm can identify patients with osteoporosis at spine or femoral neck 总被引:1,自引:0,他引:1
Forearm bone mineral density (BMD) was investigated in women to identify
osteoporosis at the spine or femoral neck (or both) defined by WHO criteria
(T score -2.5) without requirement for fracture. BMD was measured by
single-energy X-ray absorptiometry (DTX100) and by dual- energy X-ray
absorptiometry (DXA) in the lumbar spine and femoral neck in 422 subjects
aged 22-90 yr. A total of 62% of subjects with osteoporosis (at the spine,
femoral neck, or both sites) were detected with 89% specificity [receiver
operating characteristics (ROC) analysis] and included all subjects below
forearm BMD 0.34 g/cm2. Conversely, above 0.419 g/cm2, only 10% of patients
had osteoporosis. A total of 71.8% of women could be assigned either to
those who warranted therapy (<0.34 g/cm2) or to those who did not
(>0.419 g/cm2) with 90% certainty. Subjects with forearm BMD between
0.34 and 0.419 g/cm2, who constituted 28.2% of the total group and included
31% of subjects with osteoporosis, had a 40% chance of having osteoporosis.
This leads to a high identification rate on subsequent DXA scanning, which
is thus used efficiently.
相似文献
109.
Dale DC; Bonilla MA; Davis MW; Nakanishi AM; Hammond WP; Kurtzberg J; Wang W; Jakubowski A; Winton E; Lalezari P 《Blood》1993,81(10):2496-2502
Patients with idiopathic, cyclic, and congenital neutropenia have recurrent severe bacterial infections. One hundred twenty-three patients with recurrent infections and severe chronic neutropenia (absolute neutrophil count < 0.5 x 10(9)/L) due to these diseases were enrolled in this multicenter phase III trial. They were randomized to either immediately beginning recombinant human granulocyte colony- stimulating factor (filgrastim) (3.45 to 11.50 micrograms/kg/d, subcutaneously) or entering a 4-month observation period followed by filgrastim administration. Blood neutrophil counts, bone marrow (BM) cell histology, and incidence and duration of infection-related events were monitored. Of the 123 patients enrolled, 120 received filgrastim. On therapy, 108 patients had a median absolute neutrophil count of > or = 1.5 x 10(9)/L. Examination of BM aspirates showed increased proportions of maturing neutrophils. Infection-related events were significantly decreased (P < .05) with approximately 50% reduction in the incidence and duration of infection-related events and almost 70% reduction in duration of antibiotic use. Asymptomatic splenic enlargement occurred frequently; adverse events frequently reported were bone pain, headache, and rash, which were generally mild and easily manageable. These data indicate that treatment of patients with severe chronic neutropenia with filgrastim results in a stimulation of BM production and maturation of neutrophils, an increase in circulating neutrophils, and a reduction in infection-related events. 相似文献
110.
Behavior of plasminogen at the luminal surface of the normal and deendothelialized rabbit aorta in vivo and in vitro 总被引:1,自引:0,他引:1
The behavior of purified rabbit plasminogen at the luminal surface of the uninjured and deendothelialized rabbit aorta has been studied in vivo and in vitro. After intravenous injection, 125I-plasminogen associated rapidly with the endothelium (approximately 0.1 pmol/cm2 at saturation) and passed through to accumulate in the subendothelium. At two to 15 hours after injection, 11 to 15 times more radioactivity was associated with the subendothelium than with the endothelium. Removal of the endothelium by balloon catheter led to a rapid adsorption of 125I-plasminogen by the luminal surface of the vessel; saturation (9.1 pmol/cm2) was attained at ten to 20 minutes after deendothelialization. Of the adsorbed plasminogen (radioactivity), only 2% to 4% was associated with the adherent platelet monolayer. Uptake of 125I- plasminogen by the deendothelialized vessel was not significantly inhibited by epsilon-aminohexanoic acid whether injected before or after the 125I-plasminogen. No evidence of plasmin activity at the aorta surface was found from either transmission electron microscopy studies or from amidolytic assays of plasminogen-saturated deendothelialized aorta samples before or after urokinase treatment. Balloon catheter treatment in vivo, however, generated significant antiplasmin activity of the deendothelialized aorta surface. We conclude that plasmin formed in vivo is probably inactivated by the antiplasmin activity that is associated with the subendothelium. 相似文献