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Memory deficits have been reported in schizophrenia and bipolar disorder. However, the precise impact of semantic memory deficits on word comprehension, particularly across grammatical categories, has not been adequately investigated in these disorders. Furthermore, previous studies examining semantic memory have predominantly been designed so that most healthy controls perform at ceiling, questioning the validity of observed differences between patient and control groups. A new word definition task examined word comprehension across grammatical categories, i.e. nouns, verbs and adjectives, and was designed to overcome the ceiling effect. It was administered to 32 schizophrenia patients, 28 bipolar disorder patients and 32 matched healthy controls. Schizophrenia patients had a global impairment on the task but bipolar patients were only impaired on a recognition memory component. Word comprehension, however, across grammatical categories was comparable across groups. 相似文献
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目的发育迟缓是儿科常见病,许多发育迟缓的患儿首选MR成像。本研究为优化MR方案和病例选择的持续审计过程的一部分。材料与方法我们对157例发育迟缓的患儿进行常规MR成像及MR波谱检查。通过观察相关病理的总检测率来分析这些措施的效果,尤其是患儿的亚组分 相似文献
55.
Association of the steroid synthesis gene CYP11a with polycystic ovary syndrome and hyperandrogenism 总被引:12,自引:0,他引:12
Gharani N; Waterworth DM; Batty S; White D; Gilling-Smith C; Conway GS; McCarthy M; Franks S; Williamson R 《Human molecular genetics》1997,6(3):397-402
Biochemical data implicate an underlying disorder of androgen biosynthesis
and/or metabolism in the aetiology of polycystic ovary syndrome (PCOS). We
have examined the segregation of the genes coding for two key enzymes in
the synthesis and metabolism of androgens, cholesterol side chain cleavage
(CYP11a) and aromatase (CYP19), with PCOS in 20 multiply-affected families.
All analyses excluded CYP19 cosegregation with PCOS, demonstrating that
this locus is not a major determinant of risk for the syndrome. However,
our results provide evidence for linkage to the CYP11a locus (NPL score =
3.03, p = 0.003). Parametric analysis using a dominant model suggests
genetic heterogeneity, generating a maximum HLOD score of 2.7 (alpha =
0.63). An association study of 97 consecutively identified Europids with
PCOS and matched controls demonstrates significant allelic association of a
CYP11a 5' UTR pentanucleotide repeat polymorphism with hirsute PCOS
subjects (p = 0.03). A strong association was also found between alleles of
this polymorphism and total serum testosterone levels in both affected and
unaffected individuals (p = 0.002). Our data demonstrate that variation in
CYP11a may play an important role in the aetiology of hyperandrogenaemia
which is a common characteristic of polycystic ovary syndrome.
相似文献
56.
Summary: Activation of platelets and the coagulation pathway are factors which may contribute to the progression of renal disease in IgA nephropathy (IgAN). Of 21 patients with IgAN and serum creatinines between 1.6 and 3.0 mg/dL, 10 were assigned to treatment with dipyridamole and low-dose warfarin (keeping the thrombotest between 30 and 50%) and 11 to no treatment in a prospective randomized 3-year study. At entry into the trial, patients in the treatment group were younger (35 ± 6 years vs 42 ± 9 years) and had worse histological scores for tubular atrophy (1.7 ± 0.7 vs 1.1 ± 0.5) and arteriolar hyperplasia (1.4 ± 0.7 vs 0.7 ± 0.8) than those in the non-treatment group. There were no differences in serum creatinine values, creatinine clearances, urinary protein excretions, serum albumins or urinary erythrocyte counts. At the end of the trial, patients on treatment did not experience a significant increase in serum creatinine values (1.9 ± 0.3 mg/dL to 2.5 ± 1.2) or reduction in creatinine clearances (52 ± 20mL/min to 52 ± 27). Untreated patients, however, experienced a significant rise in serum creatinine values (2.1 ± 0.5 mg/dL to 3.3 ± 1.1, P < 0.01) and a fall in creatinine clearances (51 ± 26 mL/min to 31 ± 22, P = 0.06). There was no significant change in the proteinuria in either group (treatment group: 1.2 ± 1.2 g/day to 1.3 ± 1.1, non-treatment group: 1.9 ± 1.4 to 1.5 ± 1.1) and there was also no change in serum albumins and urinary erythrocyte counts. Four untreated and one treated patient developed end-stage renal failure during the course of the trial. This study suggests that treatment of patients with IgAN and renal impairment with dipyridamole and low-dose warfarin retards the deterioration of renal function, as measured by the serum creatinine and creatinine clearance. 相似文献
57.
R E Hind M Loizidou J Fleming V Batty S Birch I Taylor 《European journal of surgical oncology》1992,18(2):162-167
Lipiodol, a derivative of poppy seed oil, has been used angiographically to improve visualisation of small liver tumours. We have utilised this finding to determine whether intrahepatic arterial injection of lipiodol can be used as a vehicle to deliver selectively 131I into liver tumours. Two groups of rats were studied. Group 1 (control, no liver tumour) received 0.1 ml 131I-lipiodol (1 microCi) into the hepatic artery. Animals were killed at regular time intervals over 30 days and organs were submitted to well-counting. Over 90% of activity remained in the liver at 6 h. Eighty per cent activity was lost from the normal liver, to be excreted in the urine over 30 days. Group 2 animals received intraportal injections of 7.5 x 10(5) MC28 sarcoma cells. Multiple liver metastases were present after 14 days. Animals were similarly studied at each time interval and samples from tumour and normal liver were submitted to well-counting. Lipiodol was selectively retained within tumour and cleared from normal liver. 131I-lipiodol may prove valuable as a delivery agent for radio/chemotherapy to liver metastases. 相似文献
58.
Hajduch E Balendran A Batty IH Litherland GJ Blair AS Downes CP Hundal HS 《Diabetologia》2001,44(2):173-183
Aims/hypothesis. Increased cellular production of ceramide has been implicated in the pathogenesis of insulin resistance and in the impaired
utilisation of glucose. In this study we have used L6 muscle cells to investigate the mechanism by which the short-chain ceramide
analogue, C2-ceramide, promotes a loss in insulin sensitivity leading to a reduction in insulin stimulated glucose transport and glycogen
synthesis. Method. L6 muscle cells were pre-incubated with C2-ceramide and the effects of insulin on glucose transport, glycogen synthesis and the activities of key molecules involved
in proximal insulin signalling determined. Results. Incubation of L6 muscle cells with ceramide (100 μmol/l) for 2 h led to a complete loss of insulin-stimulated glucose transport
and glycogen synthesis. This inhibition was not due to impaired insulin receptor substrate 1 phosphorylation or a loss in
phosphoinositide 3-kinase activation but was caused by a failure to activate protein kinase B. This defect could not be attributed
to inhibition of 3-phosphoinositide-dependent kinase-1, or to impaired binding of phosphatidylinositol 3,4,5 triphosphate
(PtdIns(3,4,5)P3) to the PH domain of protein kinase B, but results from the inability to recruit protein kinase B to the plasma membrane.
Expression of a membrane-targetted protein kinase B led to its constitutive activation and an increase in glucose transport
that was not inhibited by ceramide. Conclusions/interpretation. These findings suggest that a defect in protein kinase B recruitment underpins the ceramide-induced loss in insulin sensitivity
of key cell responses such as glucose transport and glycogen synthesis in L6 cells. They also suggest that a stimulated rise
in PtdIns(3,4,5)P3 is necessary but not sufficient for protein kinase B activation in this system. [Diabetologia (2001) 44: 173–183]
Received: 5 May 2000 and in revised form: 30 October 2000 相似文献
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