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1.
S. Süreyya
zbek Remide Arkun Refik Killi Ayenur Memi Aynur Dadeviren Erkan Sevin 《Journal of clinical ultrasound : JCU》1995,23(4):233-238
Image-directed color Doppler ultrasonography (ICDUS) studies of 86 patients with superficial solid masses yielded significantly lower resistive index (RI) values in acute inflammatory lesions, but no significant difference between the maximum systolic flow velocities (S) of the patient groups with malignant, benign, and acute inflammatory lesions. When analyzed separately, the malignant soft-tissue tumor subgroup was shown to have significantly higher mean RI compared to that of the malignant node subgroup. We conclude that RI may be useful in the differentiation of acute inflammatory masses from other pathological entities. Malignant soft-tissue tumors, especially sarcomas, may have different Doppler features from those of carcinomatous tumors. © 1995 John Wiley & Sons, Inc. 相似文献
2.
Stereological evaluation of liver volume in living donor liver transplantation using MDCT via the Cavalieri method. 总被引:4,自引:0,他引:4
Cihan Duran Bulent Aydinli Yaman Tokat Yildiray Yuzer Mecit Kantarci Metin Akgun Kamil Yalcin Polat Bünyami Unal Refik Killi S Selcuk Atamanalp 《Liver transplantation》2007,13(5):693-698
In living donor liver transplantation (LDLT), obtaining the precise volume of the graft is very important to decrease volume-related postoperative complications, especially in cases with suspected small-for size grafts. We used stereology based on the Cavalieri method (CM), a new method to measure liver graft volume, and compared the results with those obtained through intraoperative measurement (IOM) and through multidetector computed tomography (MDCT) measurement. Liver volumes estimated using the 3 methods were well-correlated with each other (r(2) = 0.94 and P < 0.001 for IOM and CM; r(2) = 0.91 and P < 0.001 for IOM and MDCT, and r(2) = 0.95 and P < 0.001 for CM and MDCT); however, they were different from each other (in descending order, 908 +/- 124 cm(2), 861 +/- 121 cm(2), and 777 +/- 168 cm(2) for MDCT, CM, and IOM, respectively). Although MDCT and CM overestimated the volumes, the results of CM were almost similar to those obtained via IOM. In conclusion, our results suggest that CM measured the liver graft volume more reliably. Thus, its use, particularly in cases with suspected small-for-size graft, may prove useful. 相似文献
3.
Aravind Kumar Naresh Kumar Anirudh Gadgil 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2006,16(1):80-82
We present a case of wooden foreign bodies in the foot with delayed diagnosis. Unreliability of plain radiographs in these situations is emphasized. The comparative utility of computed tomography, magnetic resonance scans and ultrasonography is evaluated from a literature review. We utilized a sinogram which showed the splinters and also indicated their location and orientation in a region of complex anatomy, thus reducing surgical time and morbidity. Management of a suspected radiolucent foreign body is fraught with pitfalls and we provide a possible algorithm for management. 相似文献
4.
Liana Beni-Adani Naresh Biani Liat Ben-Sirah Shlomi Constantini 《Child's nervous system》2006,22(12):1543-1563
Background and objective The classification of hydrocephalus in newborns and in infants is different from the classification in adulthood. This difference
exists due to disparity in the source pathologies that produce the hydrocephalus, and the practical distinctions in prognosis
and treatment choices. The objective of this paper is to present the spectrum of obstructive-communicating hydrocephalus,
which is more complex in the pediatric group, and to propose the relevance of this particular classification to treatment
options.
Materials and methods The authors categorized infants with active hydrocephalus at time of presentation into the following four groups along the
spectrum of communicating vs obstructive HCP. Group 1: patients with a purely absorptive (communicating) HCP. In these patients,
tetraventricular dilatation is usually observed with occasional extraaxial fluid accumulation. An extracranial CSF diversion
(shunt) is the treatment of choice. Group 2: patients with an obstructive component together with a persistent absorptive
component. In these patients, a technically successful endoscopic procedure will not prevent progression of clinical symptoms
of HCP. An extracranial CSF diversion (shunt) should be the treatment of choice even though some of these patients are currently
treated by endoscopy. Group 3: patients with an obstructive component together with a temporary absorptive component. In these
patients, a technically successful ETV should be followed by temporary CSF drainage [via LP, continuous spinal drainage (CLD),
or ventriculostomy] with or without supplemental medical treatment (i.e., Diamox) for several days. Such temporary drainage
may decrease failure rate in this subgroup. Group 4: patients with a purely obstructive HCP. In these patients, an endoscopic
procedure (ETV) is the treatment of choice. According to this spectrum classification, the authors classify different entities
with representative cases and discuss relevancy to treatment options and prognosis.
Results The data suggest that obstructive hydrocephalus in the very young population may be rather a combination of obstructive and
absorptive problem. The outcome of the patient depends mainly not only on the basic pathology causing the hydrocephalus but
also on the treatment that is chosen and its complications. While bleeding and infection represent the major causes for communicating
hydrocephalus, patients with complex pathologies of congenital type and intra- or interventricular obstructions may reflect
obstructive hydrocephalus. Treatment of these patients may be successful by shuntless procedures if the absorptive problem
is not the major component. In transient absorptive hydrocephalus, temporary measures were effective in many cases leading
to successful procedures of ETV and/or posterior-fossa decompression in selected cases.
Conclusions Shuntless procedures are the dream of a pediatric neurosurgeon provided it solves the problem and does not imply unacceptable
risk. However, the benefit has to be evaluated years after the procedure is performed, as only prospective multicenter studies
will truly show which procedure may have the best overall results in the developing child. Until such studies are available,
understanding the basic pathology or the combination of pathologies leading to hydrocephalus in a given child may open the
window of opportunities for other than shunt surgery in many hydrocephalic children with major obstructive component. 相似文献
5.
Naresh Agarwal Rajnish Monga A S Puri 《Indian journal of gastroenterology》2003,22(6):238; author reply 238-238; author reply 239
6.
The entire genome of SfV, a temperate serotype-converting bacteriophage of Shigella flexneri, has recently been sequenced (Allison, G.E., Angeles, D., Tran-Dinh, N., Verma, N.K. 2002, J. Bacteriol. 184, 1974-1987). Based on the sequence analysis, we further characterised the SfV virion structure and morphogenesis. Electron microscopy indicated that SfV belongs to the Myoviridae morphology family. Analysis of the proteins encoded by orf1, orf2, and orf3 revealed that they were homologous to small and large terminase subunits, and portal proteins, respectively; the protein encoded by orf5 showed homology to capsid proteins. Western immunoblot of the phage with anti-SfV sera revealed two antigenic proteins, and the N-terminal amino acid sequence of the 32-kDa protein corresponded to amino acids 116 to 125 of the ORF5 protein, suggesting that the capsid may be processed. Functional analysis of orf4 showed that it encodes the phage capsid protease. The proteins encoded by orfs1, 2, 3, 4, and 5 are homologous to similar proteins in the Siphoviridae phage family of both gram-positive and gram-negative origin. The capsid and morphogenesis genes are upstream and adjacent to the genes encoding Myoviridae (Mu-like) tail proteins. The organisation of the structural genes of SfV is therefore unique as the head and tail genes originate from different morphology groups. 相似文献
7.
BACKGROUND: Daytime sleepiness is common in patients with sleep-disordered breathing. Although respiratory events during sleep are associated with the occurrence of daytime sleepiness, the differential impact of these events during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep on daytime sleepiness has not been well characterized. STUDY OBJECTIVES: To determine the effect of respiratory events during REM sleep and NREM sleep on daytime sleepiness, as assessed by the multiple sleep latency test (MSLT). DESIGN: Cross-sectional study. SETTING: University-based sleep disorders laboratory. PARTICIPANTS: Patients referred for polysomnography and daytime MSLT (n=1,821). INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: The study sample was initially divided into quartiles based on the level of the apnea-hypopnea index (AHI) during NREM sleep. Within the first NREM-AHI quartile (NREM-AHI < 8.3 events/hr), the association between REM-related respiratory events and daytime sleepiness was examined using the method of Kaplan-Meier analysis and Cox proportional hazards regression. After adjusting for age, gender, body mass index, and the duration of NREM and REM sleep, REM-AHI was not associated with daytime sleepiness (Relative Risk: 1.01; 95%CI: 0.94-1.10). Similarly, no significant association was observed between REM-AHI and the MSLT in patients within the second through fourth NREM-AHI quartiles. In contrast, increasing severity of disordered breathing during NREM sleep was associated with daytime sleepiness. For a 10-point increase in NREM-AHI, the adjusted relative risks for daytime sleepiness in the second through fourth NREM-AHI quartile were 1.21 (95%CI: 1.01-1.46), 1.20 (95%CI: 1.05-1.37), and 1.10 (95%CI: 1.04-1.16), respectively. CONCLUSION: Sleep-disordered breathing during NREM sleep, but not REM sleep, is associated with increased risk of daytime sleepiness. 相似文献
8.
Epstein-Barr virus association and ALK gene expression in anaplastic large-cell lymphoma 总被引:3,自引:0,他引:3
Anaplastic large cell lymphoma of T/null-cell type (ALCL) is associated with a characteristic genetic abnormality t(2;5) that results in the NPM-ALK chimeric gene and the protein product derived thereof. In 10% to 20% of ALCLs, the translocation partners of the ALK gene are genes other than NPM (variant translocations). ALK gene expression limited to the cytoplasm implies a variant translocation. In this study, we have investigated 46 cases of ALCL for expression and localization of ALK protein and its association with Epstein-Barr virus (EBV) (by hybridization to EBV-encoded nuclear RNA-1 [EBER-1] and immunostaining for LMP-1). ALCL patients with a null cell phenotype were significantly younger as compared with those of T-cell phenotype (mean age: 28 years v 42 years; P =.018). Sixteen of 46 ALCL cases (34%) were ALK positive. ALK-positive patients were significantly younger (mean age: 25 years for those with both cytoplasmic and nuclear staining; 22 years for those with exclusive cytoplasmic staining; and 41 years for those negative for the ALK gene; P =.023). EBER-1 was detected in 9 of 46 cases (20%), and LMP-1 expression was noted in 5 of them. By polymerase chain reaction analysis, all EBV-associated cases that were investigated showed type I EBV. Whereas 2 of 23 T-cell ALCLs (9%) were EBER-1+, and 7 of 23 null-cell ALCLs (30%) showed EBV association (P =.057). EBV association was seen in 20% of ALK-negative cases, in 0% of cases with ALK gene expression in both nucleus and cytoplasm, and in 60% of cases with ALK gene expression exclusively in the cytoplasm (P =.02). Further, although ALK-positive-EBER-1+ cases were LMP-1 negative, ALK-negative-EBER-1+ cases were LMP-1 positive. Our study raises the question whether EBV might have an etiological role in the evolution of ALCLs that lack classical t(2;5). 相似文献
9.
Arunaloke Chakrabarti Ashim Das Jharna Mandal M R Shivaprakash Varghese K George Bansidhar Tarai Pooja Rao Naresh Panda Subhash C Verma Vinay Sakhuja 《Medical mycology》2006,44(4):335-342
Zygomycosis is an emerging infection worldwide. A study was conducted to understand its spectrum in the Indian scenario. All patients diagnosed for invasive zygomycosis at a tertiary care center in north India from 2000-2004, were retrospectively analyzed. A total of 178 cases (mean average of 35.6 cases/year) of zygomycosis were diagnosed. Rhino-orbito-cerebral type (54.5%) was the commonest presentation followed by cutaneous (14.6%), disseminated (9.0%), and gastrointestinal (8.4%) zygomycosis. Renal and pulmonary zygomycosis were seen in 6.7% patients each. Uncontrolled diabetes mellitus (in 73.6% of cases) was the significant risk factor in all types (Odds Ratio 1.5-8.0) except renal zygomycosis. Breach of skin was the risk factor in 46.2% patients with cutaneous zygomycosis. However, no risk factor could be detected in 11.8% patients. Antemortem diagnosis was possible in 83.7% cases. The commonest (61.5%) isolate was Rhizopus oryzae followed by Apophysomyces elegans in 27% patients. Combination of debridement surgery and amphotericin B therapy was significantly better in survival of the patients (P<0.005) than amphotericin B alone (79.6% vs. 51.7% survival). Thus, a rising trend of invasive zygomycosis was observed in patients with uncontrolled diabetes mellitus in India. Consistent diagnosis of renal zygomycosis in apparently healthy hosts and the emergence of A. elegans in India demand further study. 相似文献
10.
Leydig cell tumors of the testis are rare, mostly presenting as a testicular mass or as endocrinological symptoms. Here, three patients who were admitted for investigation of primary infertility and one patient presenting with a testicular mass are reported. The histological features were reviewed and an immunohistochemical study was done using a panel of antibodies against cytokeratin, vimentin, inhibin A, S-100, Ki-67, follicle-stimulating hormone, luteinizing hormone, prolactin, p53, bcl-2, and c-erbB2. The latter case (lost during follow up of metastatic disease) demonstrated massive tumor necrosis, extension through the tunica albuginea, and a high mitotic activity and MIB-1 score. Only this malignant case was bcl-2 positive. Of the two oncogenic markers studied, none of the cases were positive for c-erb2, while p53 was positive in more than 50% of cells in the malignant case and in one case of infertility with a large tumor, hemorrhage, focal necrosis and atypical cytological features. We recommend the evaluation of infertile men for Leydig cell tumors, and we believe that a panel of antibodies, including Ki-67, p53 and bcl-2, used for immunohistochemical analysis could be of diagnostic value in the identification of malignant and borderline cases of Leydig cell tumor. 相似文献