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61.
Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder characterized by corneal endothelial abnormalities, which can lead to blindness due to loss of corneal transparency and sometimes glaucoma. We mapped a new locus responsible for PPCD in a family in which we excluded the previously reported PPCD locus on 20q11, and the region containing COL8A2 on chromosome 1. Results of a 317-marker genome scan provided significant evidence of linkage of PPCD to markers on chromosome 10, with single-point LOD scores of 2.63, 1.63, and 3.19 for markers D10S208 (at (circumflex)theta = 0.03), D10S1780 (at (circumflex)theta = 0.00), and D10S578 (at (circumflex)theta = 0.06). A maximum multi-point LOD score of 4.35 was found at marker D10S1780. Affected family members shared a haplotype in an 8.55 cM critical interval that was bounded by markers D10S213 and D10S578. Our finding of another PPCD locus, PPCD3, on chromosome 10 indicates that PPCD is genetically heterogeneous. Guttae, a common corneal finding sometimes observed along with PPCD, were found among both affected and unaffected members of the proband's sib ship, but were absent in the younger generations of the family. Evaluation of phenotypic differences between family members sharing the same affected haplotype raises questions about whether differences in disease severity, including differences in response to surgical interventions, could be due to genetic background or other factors independent of the PPCD3 locus.  相似文献   
62.
1. The rostromesial agranular frontal cortex of macaque monkey (Macaca fuscata), traditionally defined as the supplementary motor area (SMA), was studied using various physiological techniques to delineate two different areas rostrocaudally. 2. Field and unitary responses to electrical stimulation of the primary motor cortex were distinct in the caudal part, but minimal or absent in the rostral part. Intracortical microstimulation readily evoked limb or orofacial movements in the caudal part, but only infrequently in the rostral part. Neuronal responses to visual stimuli prevailed in the rostral part, but somatosensory responses were rare. The opposite was true in the caudal part. 3. The rostral part, roughly corresponding to area 6a beta, was operationally defined as the presupplementary motor area (pre-SMA). The caudal part was redefined as the SMA proper. 4. Single-cell activity in the pre-SMA was quantitatively compared with that in the SMA proper in relation to a trained motor task. 5. Phasic responses to visual cue signals indicating the direction of forthcoming arm-reaching movement were more abundant in the pre-SMA. 6. Activity changes during the preparatory period, which lasted until the occurrence of the trigger signal for the reaching movement, were more frequent in the pre-SMA. 7. Phasic, movement-related activity was more frequent in the SMA, and its onset was often time locked to the movement onset. In the pre-SMA, the occurrences of response time locked to the movement-trigger signal were more frequent than in the SMA. 8. Among neurons in both areas, directional selectivity was found in all the cue, preparatory, and movement-related responses.  相似文献   
63.
The influence of intestinal microflora and aging on the lipid metabolism in germfree (GF) and conventional (CV) rats, 8 and 40 weeks old, was investigated. Serum cholesterol at the age of 8 and 40 weeks and serum triglyceride (TG) at the age of 40 weeks was higher in GF than in CV rats. Serum cholesterol decreased and serum TG and corticosterone tended to increase in both GF and CV rats with aging. In the rats 40 weeks of age, lipase activity of the pancreas and the duodenal, jejunal, and colorectal contents in GF rats increased, but that of the ileal and cecal contents in GF and CV rats decreased. Intestinal microflora tended to depress the age-related increase of serum TG and lipase activity of the pancreas and the duodenal and jejunal contents Lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) activities of the epididymal adipose tissue were higher in CV than in GF rats at both 8 and 40 weeks of age. The LPL activity increased and the HSL activity decreased in both GF and CV rats with aging. The concentration of cholesterol increased and that of bile acids decreased in the cecal contents of 40-week-old GF rats.  相似文献   
64.
Five cases of primary sclerosing scrotal lipogranuloma were examined histologically and immunohistochemically. Every case lacked a history of injection or trauma, and revealed Common histologicat features; a typical granuloma composed of epithelioid cells and multinucleated giant cells, and inflammatory infiltrates of eosinophils, lymphocytes and macrophageimonocytes in the interstitium. lmmunahistochemistry disclosed the epithelioid cells and multinuclaated giant cells of the granuloma to be monocytetr in nature, as bath types of cells were positive for lyso-yme, α-1-antltrypin, α-1-antichymotrypsin, and KP-1. In the interstitium, KP-1 positive monocytes, L-26 positive B lymphocytes, UCHL-1 positive T lymphocytes and 5–100 protein positive Langerhans-like cells were frequently found. 5100 protein positive cells could not be detected in the granuloma. Primary sclerosing lipogranuloma of the scrotum, therefore, is a peculiar inflammation characterized by granulomas consisting of monocytes and marked tissue eosinophilia of unknown etiology.  相似文献   
65.
Obstructive jaundice was produced in rats by ligation and transection of bile duct outside the liver; the control group underwent laparotomy alone. Pancreatic wet weight, amylase, lipase, protein, DNA, RNA, RNA/DNA ratio, and weight/100 g DNA were significantly increased in jaundiced rats when compared to control rats. Histologic evaluation of pancreatic tissue obtained from jaundiced rats revealed the appearance of large or multiple nuclei in pancreatic acinar cells. Basal plasma levels of immunoreactive CCK were significantly increased in haundiced rats at two weeks and four weeks but, when compared to the levels obtained in laparotomized controls at those time intervals, CCK levels were not significantly different. In jaundiced rats, plasma immunoreactive gastrin was found to be significantly decreased at two and four weeks. Plasma gastrin levels were also found significantly decreased when the jaundiced group was compared with laparotomized control group. The results suggest that obstructive jaundice induced enlargement of the pancreas, probably due to hyperplasia and hypertrophy of pancreatic cells. Whether or not this phenomenon is related to changes in gastrin and CCK is not known.This work was presented in part at the 36th Kinki Section Meeting of Japanese Gastroenterological Association (January 1982) in Osaka, Japan; at the Annual Meeting of the Japanese Pancreatic Association (March 1982) in Hiroshima, Japan; and at the American Gastroenterological Association (May 1983) in Washington, D.C.; and appeared in abstract form inGastroenterology 84: 1095, 1983.  相似文献   
66.
Recent reports have described midterm natural courses of osteochondral lesion of the talus (OLT) and lack of progression of ankle osteoarthritis (OA) in adult patients. The relationship between the OLT managed with nonoperative treatment and development of OA in children remains unknown. We report the long-term course of medial OLT in a 12-year-old female who was treated nonoperatively for 10 years. Radiographically, no osteoarthritic changes were observed at the first examination. She initially returned to her basketball club after nonoperative treatment. Although daily activities were not restricted, limitation of recreational activities began to appear at 4 years of follow-up. Subsequently, plain radiographs revealed bone absorption around the osteochondral fragment and osteophyte formation at the medial gutter, then ankle OA was advanced at the final follow-up.  相似文献   
67.
Summary Defibrotide is known to enhance prostacyclin (PGI2) release from the vascular endothelium. We investigated the vasoactive effects of defibrotide in isolated rat hearts perfused at constant flow subjected to ischaemia and reperfusion. Defibrotide at 10–7 or 100 g/ml did not exert any direct vasoactive effect on normal rats hearts. However, ischaemia and reperfusion resulted in an impaired vasodilation to acetylcholine, an endothelium-dependent vasodilator. In contrast, the vasodilator response to the endothelium-independent dilator, nitroglycerin, was unaffected. Defibrotide, at 10–7 or 100 g/ml, markedly restored the vasodilation to acetylcholine 10–7 nmol/l to 1 mol/l (P < 0.01) without influencing the vasodilator response to nitroglycerin (2 to 200 g/1). Haemoglobin (150 nmol/l) inhibited the dilation to acetylcholine in response to defibrotide. However, no evidence of (PGI2) release was observed with acetylcholine-induced vasodilation in the presence or absence of defibrotide. Additionally, 10–100 g/ml of defibrotide did not significantly decrease superoxide radicals generated by a xanthine-xanthine oxidase synthetic system under conditions in which superoxide dismutase was effective. Thus, defibrotide appears to exert an endothelium-protective effect preserving endothelium-derived relaxing factor (EDRF) without directly scavenging free signals.Supported in part by Research Grant No. HL-25575 from the National Heart, Lung and Blood Institute of the NIH Send offprint requests to A. M. Lefer at the above address  相似文献   
68.
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.  相似文献   
69.
Cerebral amyloid angiopathy is observed in several brain degenerative disorders, but this pathological condition has received little attention in Gerstmann-Sträussler-Scheinker disease (GSS). We report a 69-year-old man who showed the cardinal features of GSS together with typical and extensive congophilic angiopathy. Immunohistochemical studies revealed that the vast majority of the amyloid plaques present in the brain of this patient were consistently labeled by anti-prion protein (PrP) antibody. Double immunostaining disclosed many additional -protein immunoreactive plaque-like lesions, including a special type of hybrid plaque with colocalization of PrP and -protein (-PrP). The vascular amyloid deposits seen in both the cerebellum and cerebrum were immunoreactive only to anti--protein antibody. It seems likely that the extensive deposition of -protein amyloid (including brain vascular amyloidosis) seen in this and other similar cases is part of pathology of GSS, although the possibility that this finding is due to ageing or concomitant Alzheimer's disease cannot be completely ruled out.Supported by a research grant from the Intractable Disease Division, Ministry of Health and Welfare, Primary Amyloidosis Research Committee, Japan  相似文献   
70.
In the testis, several types of heat shock proteins (HSPs) have been identified and characterized, although the cellular basis of the HSPs remains elusive. In the present study, alterations in the cellular localization of HSPs, including HSP 25, 60, 70, and 90, were studied during the developing and degenerating periods in the rat testis using immunohistochemistry and Western blotting. HSP25 was expressed in neither germ cells nor somatic cells on all days examined. In contrast, HSP 60 was expressed in Leydig cells during neonatal and prepuberty periods, and only in spermatogonia and primary spermatocytes after puberty. HSPs 70 and 90 were expressed in germ cells, Sertoli cells, and Leydig cells during neonatal and early developing testes, and in spermatocytes and round spermatids after puberty. Besides, there was faint expression of HSP 90 protein in spermatogonia in this period. In the degenerative condition, all HSP proteins were markedly expressed in germ cells after surgery. It would appear that HSPs play roles in unique homeostasis in testes.  相似文献   
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