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91.
OBJECTIVE: Since its foundation in 1948, Israel has received large waves of immigrants, mainly from Europe (Ashkenazic Jews, or Ashkenazim) and from North Africa and other Middle Eastern countries (Sephardic Jews. or Sephardim). In Israeli society, Ashkenazic Jews are an advantaged ethnic group, whereas Sephardic Jews are relatively disadvantaged. Little is known about the differences in drinking patterns between these two groups. The relationship between ethnicity and alcohol consumption is investigated in a 1995 data set from a sample of 4,984 subjects (60% women). METHOD: The data were collected as part of a national Israeli survey. Standardized questions covered drinking and becoming drunk in the last 12 months and drinking in the last 30 days. Unadjusted odds ratios (ORs) indicated the association of group status with the drinking variables. ORs adjusted for potential confounders were created with logistic regression. RESULTS: Unadjusted ORs indicated a negative association between all alcohol measures and Sephardic group status. ORs adjusted for such factors as socioeconomic status and religiosity produced similar results. CONCLUSIONS: This study indicates that Sephardim were less likely to drink or become drunk than were Ashkenazim. Further work is required to determine if these differences are stable or changing over time and whether such differences can be attributed to cultural or genetic factors. Similarities to U.S. patterns are discussed.  相似文献   
92.
Five unrelated patients (a male and 4 females) were affected with a previously undefined multiple congenital anomalies/mental retardation syndrome which has been designated the facio-cutaneous-skeletal (FCS) syndrome and which includes mental retardation with specific sociable, humorous behavior, characteristic facial appearance, excessive generalized skin, postnatal growth failure, and skeletal involvement. Consanguinity was noted in 2 patients, thus autosomal recessive inheritance is suggested. © 1992 Wiley-Liss, Inc.  相似文献   
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95.

Purpose

To describe the identification of a new mutation responsible for causing human severe combined immunodeficiency syndrome (SCID). In a large consanguineous Israeli Arab family, this served as a diagnostic tool and enabled us to carry out preimplantation genetic diagnosis (PGD). We also demonstrated that PGD for homozygosity alleles is feasible.

Methods

We carried out genome-wide screening followed by fine mapping and linkage analysis in order to identify the candidate genes. We then sequenced DCLRE1C in order to find the familial mutation. The family was anxious to avoid the birth of an affected child, and therefore, because of their religious beliefs, PGD was the only option open to them. The embryos were biopsied at day 3, and a single blastomere from each embryo was analyzed by multiplex polymerase chain reaction for the SCID mutation and 5 additional polymorphic markers flanking DCLRE1C.

Results

Linkage analysis revealed linkage to chromosome 10p13, which harbors the DNA Cross-Link Repair Protein 1 C (DCLRE1C) ARTEMIS gene. Sequencing identified an 8 bp insertion in exon 14 (1306ins8) of DCLRE1C in all the affected patients; this causes an alteration in amino acid 330 of the protein from cysteine to a stop codon (p.C330X). One cycle of PGD was performed and two embryos were transferred, one homozygous wild-type and one a heterozygous carrier, and healthy twins were born.

Conclusions

Identifying the familial mutation enabled us to design a reliable and accurate PGD protocol, even in this case of a consanguineous family.  相似文献   
96.
A large amount of evidence shows that the subjective evaluation of health is a predictor of survival in many different populations. Subjective health (SH) is measured using different types of measures such as a general evaluation of health or a comparative evaluation of health. The aim of this study was to compare the prediction of survival by two measures of SH (a general measure and an age-related measure) and evaluate the association with other variables in an elderly population. The baseline survey was conducted during 1994, covering 1138 men and women aged over 70. The survival status was ascertained 7 years later. After adjustment for age, sex, education, marital status, perceived socioeconomic status and presence of diseases the two SH measures were found to be predictors of mortality, but only in men. In men, there was no significant difference between the two types of SH measures in their prediction of mortality. Also in men, when there was only one or no disease, being married had a protective effect compared with not being married when both types of SH measures were used. In elderly women, the association between the two types of SH and survival diminished after adjusting for the various variables. However, the general SH measure may be the preferable measure to use when needed. Education in women was associated with mortality only via the age-related SH measure.  相似文献   
97.
Current noninvasive methods to detect structural plasticity in humans are mainly used to study long‐term changes. Diffusion magnetic resonance imaging (MRI) was recently proposed as a novel approach to reveal gray matter changes following spatial navigation learning and object‐location memory tasks. In the present work, we used diffusion MRI to investigate the short‐term neuroplasticity that accompanies motor sequence learning. Following a 45‐min training session in which participants learned to accurately play a short sequence on a piano keyboard, changes in diffusion properties were revealed mainly in motor system regions such as the premotor cortex and cerebellum. In a second learning session taking place immediately afterward, feedback was given on the timing of key pressing instead of accuracy, while participants continued to learn. This second session induced a different plasticity pattern, demonstrating the dynamic nature of learning‐induced plasticity, formerly thought to require months of training in order to be detectable. These results provide us with an important reminder that the brain is an extremely dynamic structure. Furthermore, diffusion MRI offers a novel measure to follow tissue plasticity particularly over short timescales, allowing new insights into the dynamics of structural brain plasticity.  相似文献   
98.
What goes wrong in a schizophrenia patient''s brain that makes it so different from a healthy brain? In this study, we tested the hypothesis that the abnormal brain activity in schizophrenia is tightly related to alterations in brain connectivity. Using functional magnetic resonance imaging (fMRI), we demonstrated that both resting‐state functional connectivity and brain activity during the well‐validated N‐back task differed significantly between schizophrenia patients and healthy controls. Nevertheless, using a machine‐learning approach we were able to use resting‐state functional connectivity measures extracted from healthy controls to accurately predict individual variability in the task‐evoked brain activation in the schizophrenia patients. The predictions were highly accurate, sensitive, and specific, offering novel insights regarding the strong coupling between brain connectivity and activity in schizophrenia. On a practical perspective, these findings may allow to generate task activity maps for clinical populations without the need to actually perform any tasks, thereby reducing patients inconvenience while saving time and money.  相似文献   
99.
Developing novel anti-platelet therapies is an important clinical strategy for the prevention of arterial thromboses which cause heart attacks and most strokes. Thrombin activates platelets via protease-activated receptors (PARs), and PAR antagonists are currently under investigation as antithrombotics. Yet despite these clinical advances, the importance of PARs to platelet activation during thromboses formed under pathological conditions has not been investigated. To this end, we examined the role of PAR-dependent platelet activation in thrombus formation in the presence of elevated blood shear rates. We used two in vivo thrombosis models and an ex vivo whole blood flow approach in PAR4(-/-) mice, whose platelets are unresponsive to thrombin, to show that the contribution of PAR-mediated platelet activation to thrombosis is diminished at pathological blood shear rates as a direct result of decreased incorporation of thrombin-activated platelets into growing thrombi. Our ex vivo observations were replicated in human whole blood treated with a PAR1 antagonist. These results define a novel, shear-regulated role for thrombin/PAR-dependent platelet activation during thrombosis and provide important insights into the conditions under which PAR antagonists may best be used for the prevention of acute coronary syndromes.  相似文献   
100.

Purpose

To retrospectively analyze the evolution of indeterminate hepatocellular nodules in cirrhotic patients on serial Gd-EOB-DPTA-enhanced MRI, and to identify predictors of HCC development.

Materials and methods

This IRB approved study included 33 cirrhotic patients with 69 indeterminate hepatocellular nodules (mean diameter 1.1 cm) at baseline Gd-EOB-DPTA-enhanced MRI and a Gd-EOB-DPTA-enhanced-MRI follow-up of at least 2 years. Two radiologists evaluated size and signal intensity of each nodule at baseline and follow-up. Age, cirrhosis etiology, and HCC history were recorded. Data were compared between nodules that became HCCs at follow-up (HCC) and those that did not (no-HCC).

Results

On follow-up, 5/69 nodules became HCCs and 64/69 showed indeterminate characteristics. HCC history was more frequently found in HCCs than in no-HCCs. Age, sex, and cirrhosis etiology were not significantly different between HCCs and no-HCCs. HCCs had a significantly greater baseline diameter and increase in size than no-HCCs. Hepatobiliary phase hypointensity was significantly more common in HCCs than in no-HCCs. Multivariate regression analysis showed that increase in size (OR 10.48; sensitivity, 100%; specificity, 81.2%; p?<?0.001) and hepatobiliary phase hypointensity (OR 1.02; sensitivity, 100%; specificity, 78.1%; p?<?0.001) was associated with HCC development.

Conclusion

Indeterminate hepatocellular nodules at Gd-EOB-DPTA-enhanced MRI in cirrhotic patients rarely became HCCs. Hepatobiliary phase hypointensity had a weak association with HCC development.
  相似文献   
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