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111.
The presence and distribution of anionic sites in the glomerular basement membrane and visceral epithelial cell coat has been demonstrated. No definite decrease in intensity or periodicity of staining of basement membrane particulate sites was seen in protein overload proteinuric animals and only one staining technique employed for electron microscopy (alcian blue 8GX) demonstrated a focal decrease in visceral epithelial cell coat staining in severely damaged glomeruli. A decrease in overall glomerular staining was also demonstrated by quantitative analysis of colloidal iron staining by light microscopy. The findings differ from those described in puromycin aminonucleoside nephropathy and nephrotoxic nephritis. Staining was demonstrated also in other basement membranes, in Bowman's capsule and along interstitial collagen fibres.  相似文献   
112.
Biliary tract obstruction in a 30-year-old man was found to be caused by a malignant melanoma in the common bile duct. Melanin pigment was demonstrated by immunohistochemistry and electron microscopy. Extensive search for a primary malignant melanoma elsewhere was unsuccessful. No pigmented lesions had been removed previously. There were junctional changes in the mucosa of the common bile duct close to the tumor. The malignant melanoma in the common bile duct therefore is considered to be primary. Only one other case of primary malignant melanoma in the common bile duct has been described in the literature, whereas metastases to the major bile ducts in one autopsy study of malignant melanoma in the more common locations were found with a frequency of 6 per cent.  相似文献   
113.
In most HIV-1-infected patients, clinical and immunological progression develops within a few years. Few infected people, termed long-term non-progressors (LTNP), remain healthy and immunologically stable for a long time. The factors governing the maintenance of this condition are not well known, but it is conceivable that CD8+ lymphocytes, cells that play a central role in controlling in vitro HIV replication, may have a part in vivo in this process. The aim of this study was to characterize the phenotypic profile and the cytokine production of CD8+ cells in a group of LTNP patients who had stable CD4+ cell counts (>500/mm3) for at least 7 years. Their CD8+ absolute numbers were similar to a control group composed of HIV-1+ patients who have a progressive decline of their CD4+ cell counts. However, our multiparameter immunofluorescence studies show that a clinical and immunologically stable condition is associated with the presence of a CD28+, CD95 strongly positive CD8+ population, while disease progression is marked by the CD28CD95+CD8+ subset. Purified CD8+ cells from LTNP retain their ability to produce IL-2, interferon-gamma (IFN-γ) and, to a lesser degree, to produce IL-10 and IL-4. In contrast, CD8+ cells from progressors are unable to secrete IL-2 and IL-10. Although CD8+ cytokine profile does not fit with the proposed T helper (Th)1/Th2 switch in progressive HIV infection, LTNP CD8+ T cells maintain their capacity to produce IL-2 and IL-10 (Th0-like), a pattern very similar to that observed in normal HIV healthy controls. We suggest that CD8+ cells expressing CD28, CD95 and having a Th0-like profile may be considered to be associated with long-term survival.  相似文献   
114.
A Caucasian female patient with repetitive attacks of ventriculartachycardia and fibrillation caused by annular submitral leftventricular aneurysm is reported. During a follow-up periodof six years after aneurysmectomy, the patient remained symptom-free.  相似文献   
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117.
In Situ Study of Haemopoiesis in Human Fetal Liver   总被引:4,自引:0,他引:4  
The anatomy of haemopoietic cells in human fetal liver was examined using immunohistological techniques on frozen sections of 31 fetuses (10-28 weeks gestational age). The immunohistological findings were consistent with reported cell suspension data. With regard to the location of haemopoietic activity no particular relationship existed between the various haemopoietic cell lineages. A large number of proliferating cells was present; only a few of these were reactive with haemopoietic progenitor cell monoclonal antibodies (MoAb) CD34. A population of haemopoietic cells expressed CD43 antigen (MoAb MT1) alone or together with anti-vimentin MoAb reactivity; this population needs further delineation. Erythropoiesis and myelopoiesis occurred in clusters around sinusoids and portal triad vessels respectively. Lack of MoAb reacting exclusively with early developmental stages of erythropoiesis and myelopoiesis precluded dissection of these lineages. Lymphopoiesis occurred in a loosely scattered pattern without any sign of focal development. Pre-B and B-cell numbers increased with gestational age. Cells expressing markers of more mature B cells (surface IgD, CD35, and CD21) were rare. Also, few cells reacted with mature T-cell markers, but CD7+ cells were obviously present. This expression of CD7 on haemopoietic fetal liver cells suggests that T-cell precursors develop in fetal liver as well as B cells.  相似文献   
118.
In search for an alternate treatment for inoperable cancer of the lung in humans, we investigated the possibility that introduction of radioactive material into a selected lobe of the canine lung would effectively destroy that lobe without systemic effects or radiation injury to adjacent organs. Ten million ion exchange microspheres labeled with 740 MBq of phosphorus-32 (32P) were injected through a catheter placed in a selected lobar branch of a pulmonary artery in 12 anesthetized dogs. Six additional dogs served as controls and received 10 million microspheres not labeled with 32P. Organs were harvested from 1 wk to 12 mo after injection and examined grossly and histologically. There was progressive organization and contraction of each necrosed 32P treated lobe which was reduced to a scarred remnant by 12 mo, whereas only minimal inflammatory changes occurred in controls. Of the 32P injected dose, 94% remained in injected lobe, 4%-5% in nontargeted lobes and less than 0.08% in blood. Radioactivity in liver, kidneys, spleen, heart, and bone marrow was less than 0.1% for each organ. Thus, large doses of radiation in the order of 1,500 Gy can be effectively delivered to a selected lobe to produce a "radioisotopic pulmonary lobectomy."  相似文献   
119.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
120.
The aim of this study was to assess the prevalence of long-termcomplications in all patients with non-insulin-dependent diabetesmellitus, who were known to their general practitioners (GPs).During one year 19 GPs in the area of Hoogeveen in the Netherlandsexamined their non-insulin-dependent (NIDDM) patients, includingthose under specialist's care. A detailed protocol was used;the GPs were trained in the diagnostic procedures. Complicationswere either already known from the records or newly discoveredduring screening. In a population of 41940 14.5/1000 patientswith diabetes were identified: 12/1000 NIDDM and 2.5/1000 insulin-dependent-diabetesmellitus (IDDM). Of the 509 NIDDM patients, 387 (76%) couldbe screened for late complications. Signs and symptoms of latecomplications were found in many patients: retinopathy (14%),nephropathy (57%), neuropathy (68%) and macroangiopathy (53%).The prevalence of serious complications was: proliferative retino-and maculopathy (3.3%); diabetic foot (2.6%); renal failure(2.5%). The systemic screening revealed a high number of previouslyunknown cases. It is concluded that many patients with NIDDMdevelop signs and symptoms of late complications. Most casesare identified by systemic screening only. More long-term studiesof the prognosis of late com plications in NIDDM are needed.  相似文献   
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