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101.
Achalasia is an esophageal motor disorder characterized by abnormal relaxation of the lower esophageal sphincter and absence of progressive peristalsis in the esophageal body. Previous studies evaluating esophagomyotomy and esophageal resection specimens have shown the presence of myenteric inflammation to be a consistent and early pathologic change in patients with achalasia. Thus, the goal of this study was to determine the immunohistochemical characteristics of the inflammatory infiltrate within the myenteric plexus in patients with clinically early and end-stage achalasia. Using formalin-fixed tissue, we analyzed the immunohistochemical features of the myenteric lymphocytes using antibodies that recognize B cells (CD20), T cells (CD3), T cell subsets (CD8), and the activation state of T cell subpopulations (TIA-1 and granzyme B) in nine patients with clinically early achalasia who underwent esophagomyotomy and 13 patients with clinically endstage achalasia who underwent esophageal resection. The myenteric infiltrate in all nine esophagomyotomy specimens was composed predominantly of T cells (CD3-positive), the majority of which also stained for CD8. In five of nine specimens, the majority of CD8-positive cells stained for TIA-1. In the esophageal resection specimens, the myenteric infiltrate was composed predominantly of CD3-positive T cells in seven of 13 cases. In three cases, there was a predominance of CD20-positive B cells, and in the remaining three cases there were relatively equal numbers of T and B cells. In eight of 13 cases, the majority of T cells stained for CD8. TIA-1 immunoreactivity was found in the majority of CD8-positive cells in nine of 13 cases. In all esophagomyotomy and esophageal resection specimens studied, rare granzyme B-positive cells were detected. In conclusion, the majority of myenteric inflammatory cells in patients with achalasia are CD3-positive T cells, most of which are also CD8-positive, although the relative percentage of such cells appears to decrease with disease progression. Furthermore, many of the CD3-positive/CD8-positive myenteric lymphocytes also express TIA-1, suggesting they are resting or activated cytotoxic T cells. The immunohistochemical demonstration of granzyme B in a subpopulation of these cells supports the contention that achalasia is an immune-mediated disease, although the inciting antigen remains an enigma.  相似文献   
102.
Parental awareness of risk factors for sudden infant death syndrome (SIDS) and infant care practices were compared in an area of relative deprivation and one of relative affluence in Cardiff. Awareness was high in both areas. More infants slept on the side in the deprived area (p < 0.02). One in three babies was exposed to cigarette smoking, significantly more in the deprived area (p < 0.001). Health professionals should discourage side sleeping and smoking, especially in areas of deprivation.  相似文献   
103.
104.
We treated 20 women with locally advanced breast cancer between January 1991 and September 1996, The treatment regimen included 4 cycles of intensive doxorubicin (30 mg/m2/ d on 3 consecutive days every 2 weeks with G-CSF support), followed by appropriate surgery, followed by high dose therapy with cyclophosphamide, carboplatin and thiotepa (STAMP V, CTCb). Of the 20 patients, seven presented with inflammatory breast cancer, three with Stage HIB, seven with stage IIIA, one with multifocal Stage IIB and two with Stage IV M1 (ipsilateral supraclavicular lymph node involvement) (including one who had an inflammatory primary) disease. Six patients had not undergone mastectomy at the time of entering the protocol. These six received the doxorubicin in a neoadjuvant fashion and were thus evaluable for tumor response. The remaining 14 received doxorubicin as adjuvant therapy prior to intensification and transplantation. All patients underwent local-regional radiation therapy and were placed on oral tamoxifen. Doxorubicin was well tolerated in this schedule with ali but three patients receiving all their cycles on schedule. Both BM and PBPC were easily collected after this regimen and, when reinfused, resulted in the prompt recovery of granulocytes (median 11 days to 500 absolute granulocyte count) and platelets (median 13 days to 20000 platelets). The six patients who received doxorubicin prior to mastectomy all had major clinical responses, but were found to have microscopic focii of breast cancer in the mastectomy specimens. The overall treatment was well tolerated with the exception of one treatment-related death (5%). The overall and relapse free survival are 70% and 58% respectively with a median follow-up of 40 months (range 12–74 months). When the Stage IV patients are censored, the relapse-free survival rate is 69%. In the bone marrow transplant phase of treatment, the major non-hematologic toxicities were stomatitis (70%) and anorexia requiring parental nutrition (75%).  相似文献   
105.
The innervation of the digits on the raccoon forepaw was examined by using immunochemistry for protein gene product 9.5, calcitonin-gene related peptide, substance P, neuropeptide-Y, tyrosine hydroxylase, and neurofilament protein. The larger-caliber axons in the ventral glabrous skin terminate as Pacinian corpuscles deep in the dermis, small corpuscles and Merkel endings around the base of dermal papillae, and Merkel endings on rete pegs in dermal papillae. Extensive fine-caliber innervation terminates in the epidermis and on the microvasculature. The innervation is more dense in the distal than in the proximal volar pads. Pacinian endings are also concentrated in the transverse crease separating the distal and proximal pads. In the dorsal hairy skin, hair follicles are well innervated with piloneural complexes. Merkel innervation is located under slight epidermal elevations and in some large Merkel rete pegs located at the apex of transverse skin folds just proximal to the claw. No cutaneous Ruffini corpuscles were found anywhere on the digit. The claw is affiliated with dense medial and lateral beds of Pacinian endings, bouquets of highly branched Ruffini-like endings at the transition from the distal phalanx and unmyelinated innervation in the skin around the perimeter. Encapsulated endings are located at the lateral edge of the articular surface of the distal phalanx. Extensive fine-caliber innervation is affiliated with sweat glands and with the vasculature and is especially dense at presumptive arteriovenous sphincters. Virtually all of the sweat gland and vascular innervation is peptidergic, whereas most of the unmyelinated epidermal innervation is nonpeptidergic.  相似文献   
106.
The organization of several laminated structures in the brain is controlled by a signaling pathway activated by Reelin, a large glycoprotein secreted by pioneer neurons in the developing brain. Reelin binds to transmembrane receptors, including VLDLR and ApoER2, and stimulates tyrosine phosphorylation of Disabled-1 (Dab1), which associates with an NPxY motif present in the cytoplasmic domain of the receptors. Disruption of reelin, dab1, or both the vldr and apoer2 genes results in similar cell positioning defects in laminated brain regions including the cerebellum, hippocampus, and cerebral cortex. Although retinal ganglion cells express reelin during development, there is no obvious disruption of cell positioning in the retina of reeler mice. Here, we examine the expression pattern of Dab1 as a first step toward understanding the function of the Reelin signaling pathway in neural retina. Immunohistochemical analysis of the adult retina revealed that Dab1 is expressed in a specific type of amacrine cell. These cells display a narrow dendritic field and they project to two distinct sublaminae within the inner plexiform layer. Dab1 co-localizes with the high-affinity glycine transporter, indicating that these amacrine cells are glycinergic. Cells that express Dab1 are surrounded by dopaminergic fibers originating from wide-field amacrine cells. These features are characteristic of type AII amacrine cells described in other mammalian species. Analysis of the retina at several stages of development revealed that Dab1 is expressed shortly after birth during the time at which AII amacrine cells extend neurites and form synaptic connections in the inner retina. This raises the possibility that the Reelin/Dab1 signaling pathway contributes to formation of intraretinal circuitry in the neural retina.  相似文献   
107.
The surgical resection of Wilms' tumor can be complicated by tumor thrombus extension into the inferior vena cava. In cases of suprahepatic Wilms' tumor thrombus that may extend into the right atrium, a median sternotomy and cardiopulmonary bypass (CPB) are used to facilitate tumor resection. However, if the tumor can be localized and controlled below the atrium, resection without the use of cardiopulmonary bypass may limit morbidity. The authors describe a novel approach to tumor thrombectomy for a Wilms' tumor extending to the suprahepatic vena cava without the use of CPB. The authors used transesophageal echocardiography to localize the tumor thrombus and detect any tumor or air embolization and a minimal lower sternotomy to obtain intrapericardial control of the inferior vena cava. This technique may be useful in selected cases of Wilms' tumor as an alternative to median sternotomy and use of cardiopulmonary bypass.  相似文献   
108.
109.
G.E. Rice  G.D. Thorburn 《Placenta》1986,7(6):533-542
Phospholipid metabolites have previously been implicated in receptor-mediated stimulation of protein hormone secretion. As the factors which regulate the release of choriomammotrophin remain to be elucidated, we investigated the potential involvement of phospholipase C-induced phospholipid metabolism in the release of this placental hormone. Phospholipase C (PLC) caused a dose-dependent release of choriomammotrophin from ovine placenta, incubated in vitro. At a concentration of 0.2 units/ml (0.25 microgram protein/ml), PLC caused the release of choriomammotrophin from placental tissue to approximately double that observed in control incubations (7.08 +/- 0.4 micrograms/50 mg/h and 3.26 +/- 0.3 micrograms/50 mg/h, respectively). PLC treatment did not significantly alter plasma membrane permeability, as indicated by the release of lactate dehydrogenase and protein. PLC-stimulated release of oCM was completely abolished by incubation in calcium-free medium or by preincubation with the inorganic calcium-channel blocking agents cobalt chloride (4 mM) and lanthanum chloride (1 mM). The effects of PLC treatment on ovine choriomammotrophin (oCM) release were also inhibited by preincubation of placental tissue with inhibitors of arachidonic acid metabolism: ibuprofen (10(-5) M), naproxen (10(-4) M) or nordihydroguaiaretic acid (NDGA) 5 X 10(-6) M). These results suggest that the effects of PLC on the release of choriomammotrophin are mediated via metabolites of arachidonic acid.  相似文献   
110.
A new hereditary syndrome characterized by a frontoparietal lobe pseudotumor and retinal capillary abnormalities is described. A pedigree is presented in which characteristic ophthalmic findings have been found in ten family members and are suspected in eight additional family members spanning a total of four generations. Typical retinal findings include perifoveal capillary obliteration, peripheral focal capillary occlusion, and microvascular abnormalities, particularly involving the posterior pole. Eight patients spanning three generations had a central nervous system pseudotumor with identical histopathology. Histopathologic analysis of brain tissue shows a characteristic pattern of an unusual vasculopathy without vasculitis characterized by fibrinoid necrosis and resulting in necrosis of white matter with sparing of cortical brain tissue. The pedigree shows an apparent autosomal dominant pattern of inheritance with delayed expression of abnormalities. Of note, two patients unrelated to the pedigree having similar neuropathologic and retinal findings also have been seen at the authors' institution.  相似文献   
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