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1.
A female infant with nesidioblastosis who showed mild clinical symptoms is reported. In this patient, insulin levels and insulin to glucose ratios (IRI/G) were often normal. Regular milk feedings supplemented with continuous glucose infusion (0.7-2 mg/kg per min) or oral glucose feedings (4.5 mg/kg per min) prevented hypoglycemia. As leucine-sensitivity was diagnosed at 2 months of age, she was started on diazoxide. This was, however, ineffective, and adverse effects appeared. Subtotal pancreatectomy (95%) was therefore attempted at 5 months of age, and persistent normoglycemia as well as normal growth and development followed up to 3 years after the operation. The pancreas showed characteristic signs of nesidioblastosis. The above clinical observation suggests that a patient with nesidioblastosis whose blood glucose level is easily controllable may develop an unexpected episode of hypoglycemia in the presence of a leucine sensitivity. In such a patient, diazoxide or, when it is of no avail, surgical intervention should promptly be instituted to prevent possible neurologic sequelae induced by hypoglycemia.  相似文献   
2.
A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
3.
We studied T cell responses to four glutathione S transferase (GST)-fused mite antigens prepared in our laboratory using peripheral blood lymphocytes from mite-sensitive patients with bronchial asthma. Of the four recombinant antigens, purified GST-Mag3 had the strongest ability to cause patients' lymphocytes to proliferate, and its potency was almost comparable to that of crude mite bodies (Dfb) and faeces (Dff) antigens and a purified major antigen, Der f 2. The responder lymphocytes were mainly T cells, because the proliferative response was depleted by the treatment of lymphocytes with anti-CD3 antibody and complement, but not with anti-CD20 antibody and complement. The responsiveness of lymphocytes to GST-Mag3 correlated with that to Der f 2, but GST-Mag3 displayed slightly higher activity to stimulate lymphocytes than Der f 2. Simultaneously, the levels of Dff- and GST-Mag3-specific IgE antibodies correlated with the responsiveness of lymphocytes to GST-Mag3. These results suggest that Mag3 is a new valuable antigen for the response of T cell proliferation in mite-sensitive patients.  相似文献   
4.
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity, in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5 cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
5.
Structural changes in the developing rat lung were studied by a combined use of light microscopy including immunohistochemistry for a-smooth muscle actin (alpha-SMA) and scanning electron microscopy (SEM) using the KOH-collagenase digestion method. In the embryonic stage (E11-E13), the lung bud appeared as an outgrowth from the ventral wall of the foregut which grew caudally into the splanchnic mesoderm to form a pair of bronchial buds at the end. At E13, the airway smooth muscle cells first appeared around the bifurcation of the trachea. These smooth muscle cells were restricted to the dorsal surface of the tracheal epithelium, suggesting a difference in character between the dorsal and ventral sides of the mesenchymal cells in this region. During the pseudoglandular stage (E13-E18.5), the bronchial buds repeatedly gave off branches in the mesenchymal tissue. The smooth muscle cells in the bronchioles were spindle-shaped and arranged completely circularly around the epithelial tube, except that the terminal bud of bronchioles lacked the smooth muscles. The neck of the terminal bud was constantly surrounded by flat and irregularly-shaped immature smooth muscle cells, representing an early event in the smooth muscle cell differentiation from mesenchymal cells. In the canalicular to saccular stages (E18.5 to birth), the terminals of bronchioles became saccular, thus forming prospective alveolar acini. At birth, the alveolar wall became thinner than before birth, and the individual smooth muscle cells in bronchioles were elongated like a tape. As to the blood vessel differentiation, various sized sinusoidal spaces indicating the primitive blood vessels were already present in the mesenchymal tissue at E11.5. The endothelial cells of these sinusoidal spaces were irregularly shaped and sometimes extended their processes into the lumen. The network of tubular vessels appeared from E14.5. These vessels had tapering ends as well as transluminal trabeculae, suggesting that capillary growth proceeds by both the sprouting and partitioning (i.e., intussusception) of vessels in the pseudoglandular stage.  相似文献   
6.
Peripheral lymphocytes from eight patients with congenital immunodeficiency diseases were infected with Epstein-Barr virus (EBV) in an attempt to establish B lymphoblastoid cell lines (LCL). These patients included three boys with congenital agammaglobulinaemia, two girls with hypogammaglobulinaemia, one boy with common variable immunodeficiency, one boy with severe combined immunodeficiency with adenosine deaminase deficiency, and one boy with DiGeorge syndrome. Five of the patients bore no surface immunoglobulins (slg) on their peripheral lymphocytes. LCL were established from seven of the eight patients. All the LCL established formed rosettes with EAC3 and had the ability to produce cytoplasmic immunoglobulins (clg) of various classes. Culture supernatants concentrated up to 100-fold developed precipitin bands by Ouchterlony's method with antisera to human Ig in all the established LCL. These results suggested that both slg-, clg- and C3+ cells and slg+, clg- and C3+ cells might be the target cells for EBV and that slg-, clg- and C3+ cells might be the precursor cells of B lymphocytes.  相似文献   
7.
Neuropeptide Y (NPY) has at least three receptors (Y1, Y2 and Y3) through which it influences different mechanisms in many cell types. Previous data suggest that the Y2 receptor may be divided into prejunctional and postjunctional subgroups. We have examined the intracellular signalling pathways of the postjunctional Y2 receptor in rat renal proximal tubules. The results indicate that NPY regulates Na+,K+-ATPase through several signalling pathways: (1) In proximal tubule (PT) cells NPY increased intracellular calcium. The response was blocked by removing extracellular calcium and was also blocked by using nifedipine. This suggests that calcium was increased by influx from the extracellular space through L -type calcium channels. (2) NPY increased Na+,K+-ATPase activity in PT segments and this effect was also blocked by nifedipine. CaMKII-Ala286[281–302] a blocker of Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibited the NPY-stimulated Na+,K+-ATPase activity. This implies that increased intracellular calcium activates CaMKII which subsequently increases Na+,K+-ATPase activity. CaMKII thus appear to act similar to what has been proposed for protein phosphatase 2B. (3) Calphostin C, an inhibitor of protein kinase C (PKC), did not inhibit NPY-stimulated Na+,K+-ATPase activity. PKC is, therefore, unlikely to be involved. (4) Y2 receptors are negatively coupled to the cAMP pathway. NPY attenuated forskolin-stimulated cAMP production in renal tubules and exogenous cAMP counteracted the NPY-stimulated Na+,K+-ATPase activity. This illustrated the importance of NPY for the regulation of renal sodium handling. We also propose that the renal tubule cell is a good model for studying the function and mechanisms of postjunctional Y2 receptors.  相似文献   
8.
The effect of temperature on the potencies of neuromuscularblocking agents remains unclear. This study was undertaken toexamine the effects of different neuromuscular blocking agentsat 37 and 27 °C at a constant carbon dioxide content ( statprinciple). The effect of neostigmine 1 µmol litre–1induced antagonism of these agents was also investigated. Phrenicnerve-hemidiaphragm preparations of rats were mounted in modifiedKrebs solution, maintained at 37 CC and aerated with a 5% carbondioxide-95% oxygen gas mixture, and at 27 °C with 4% carbondioxide to maintain the carbon dioxide content of the solutionconstant. Phrenic nerves were stimulated with 0.1 -Hz supra-maximalimpulses of 0.2-ms duration and the elicited tension of thediaphragm recorded. The potencies of the steroidal neuromuscularblocking agents (rocuronium, vecuronium, pancuronium and pipecuronium)increased significantly at 27 °C (P<0.05), while thepotencies of the benzyliso-quinolinium agents (tubocurarineand dimethyl-tubocurarine) did not change. Neostigmine-inducedantagonism of the steroidal agents did not differ significantlybetween each other but differed significantly from the benzylisoquinoliniumagents (P<0.05) at both temperatures. The ratios of IC50(inhibitory concentration, 50%) with and without neostigmineat hypothermia were slightly higher for the steroidal agents,indicating slight enhancement of antagonism by neostigmine at27 °C. In contrast, the ratios were significantly greaterat 27 °C (P<0.05) for isoquinolinium agents, implyingsignificant enhancement of antagonism. Our results indicatethat at 27 °C the potency of all steroidal agents increasedand neostigmine-induced antagonism was slightly enhanced. Withthe isoquinolinium agents, hypothermia caused no change in potencyalthough neostigmine-induced antagonism was enhanced significantly.These findings suggest that the relative effects of steroidaland isoquinolinium agents on the neuromuscular junction aredifferent or that they have a different mechanism of actionon the neuromuscular junction.  相似文献   
9.
Pancreas-sparing duodenectomy (PSD), which allows preservation of the pancreas in its entirety, is a promising procedure for low-grade malignancies of the duodenum, the periampullary region, and the neighboring retroperitoneum. We report a case of recurrent retroperitoneal liposarcoma involving the second and third parts of the duodenum, which was extirpated using PSD, after a right hemicolectomy for tumor invasion of part of the colonic hepatic flexura. The Roux-en-Y jejunal limb was sutured to the duodenal bulb in an end-to-end fashion, and the biliary and pancreatic duct systems were reconstructed with end-to-side anastomoses, placing the jejunal limb distal to the bulbo-jejunostomy after a septoplasty to repair the adjacent pancreatic and biliary ducts. Because retroperitoneal liposarcoma has a low incidence of lymph node metastasis, pancreaticoduodenectomy may be inappropriate, especially if minimally extensive surgery can ensure organ preservation. Pancreas-sparing duodenectomy could be the most appropriate procedure for nonepithelial malignant tumors located around the duodenum distal to the pylorus, which have no involvement with the pancreatic parenchyma or periduodenal lymph nodes.  相似文献   
10.
Dermatitis herpetiformis (DH) is common in some Caucasian populations but extremely rare in Japanese, probably because of different immunogenetic backgrounds. We report two Japanese DH cases with typical clinical, histological and direct immunofluorescence features. However, no symptom of gluten‐sensitive enteropathy was shown. The diagnosis was confirmed by eliminating other autoimmune blistering diseases by indirect immunofluorescence, enzyme‐linked immunosorbent assays and immunoblotting. However, circulating immunoglobulin (Ig)A anti‐endomysium, reticulin and gliadin antibodies were not detected. IgA antibodies to tissue and epidermal transglutaminases were also negative. One case was associated with lung cancer and the other one with autoimmune pancreatitis. On review of 17 cases of DH reported in Japan over the previous 10 years, including our cases, one case was associated with gluten‐sensitive enteropathy, four with malignant neoplasms, two with autoimmune systemic disorders and one with psoriasis. Although our cases were typical of DH in clinical, histopathological and IgA deposit features, they showed different human leukocyte antigen haplotypes, no gluten‐sensitive enteropathy and no DH‐specific IgA antibodies, including those to epidermal and tissue transglutaminases. These results suggest that studies of unique characteristics in Japanese DH patients should facilitate further understanding of pathogenesis in DH.  相似文献   
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