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41.
Aims: To estimate the size of the drug-using population in Lambeth, an inner city London borough, and the prevalence of blood-borne virus (BBV) infections in the drug-using population. To identify possible shortfalls in service provision for drug users.

Methods: Direct and indirect estimates of the drug-using population size using national and local data sources. Prevalence estimates for BBV infections were derived from local survey data. Routine data and a survey of borough services for drug users were compiled.

Findings: Based on indirect methods we estimated there were 3117 drug users in Lambeth in 2001-2002 (20 per 1000, 15- to 44-year-olds), of whom 1641 were injecting users (11 per 1000); 1353 were reported as being in drug treatment programmes. BBV prevalence rates: hepatitis B, 37%; hepatitis C, 71%; HIV, 6%. Estimated demand for needle exchange services, in terms of one syringe per injection, and methadone maintenance may be up to double local provision.

Conclusions: More accurate and feasible methods are needed for the routine estimation of the population of drug users. Accurate information is needed for service planning.  相似文献   
42.
A group of 16 male patients with infertility had dermatitis of the scrotum and groins giving lichenified oedematous skin; the resulting thickening and loss of rugosity produced a characteristic appearance that we have termed wash leather scrotum. Treatment of the dermatosis resulted in an improvement in sperm count and motility in most patients, and 5 couples produced one or more pregnancies.  相似文献   
43.
Neonatal adrenal haemorrhage with renal vein thrombosis, an almost exclusively left-sided phenomenon, may occasionally be bilateral in the presence of inferior vena cava thrombus but has only twice been reported as confined to the right side. These cases required a combination of ultrasound (USS), excretion urography, cystoscopy with retrograde pyelography, radioisotopes, and CT to diagnose this rare right-sided combination. We report a case of right adrenal haemorrhage causing right renal vein thrombosis accurately diagnosed using only duplex USS and radioisotopes. The potential complications of renal vein thrombosis and hypertension associated with adrenal haemorrhage requires accurate diagnosis and this paper emphasises the value of duplex USS.  相似文献   
44.
Seventy-six subfertile men with significant titers of antisperm antibodies were treated with a new corticosteroid regimen, consisting of prednisolone, 40 mg daily, rising to 80 mg daily if antibody titers did not fall, given from days 1 to 10 of the partner's menstrual cycle, for up to nine cycles. Twenty-five (33%) of the partners became pregnant during a treatment cycle, more than twice the expected incidence without treatment. No serious complications occurred, although one half of the patients had transient minor side effects. This regimen appears to be encouraging and suitable for further assessment in a prospective controlled trial.  相似文献   
45.
A retrospective study was made of 9 patients with congenital lobar emphysema who presented over the past 13 years. The ages of the patients at diagnosis ranged from 2 weeks to 10 years. The earlier the presentation, the more severe were the symptoms. Two patients were misdiagnosed initially at the referring hospitals with near disastrous results. Pitfalls in diagnosis are outlined and the various investigative procedures discussed. A flow chart for the diagnostic approach is presented. Treatment was usually by lobectomy but 2 older children presenting late with mild symptoms were managed conservatively with satisfactory results.  相似文献   
46.
Phosphatidylinositol 3-kinase (PI3-kinase) and phosphatidylinositol 4-kinase (PI4-kinase) enzymes are an important family of signaling molecules that have been implicated in the regulation of intracellular vesicle trafficking. It has previously been shown that PI3-kinase and PI4-kinase enzymes regulate neuronal survival and the retrograde axonal transport of nerve growth factor in sympathetic and sensory neurons. We have extended these studies to examine the role these enzymes play in the regulation of the retrograde axonal transport of neurotrophin-3 (NT-3) and neurotrophin-4 (NT-4) in sympathetic and sensory neurons in vivo. Wortmannin (0.1 nmol/eye), a PI3-kinase and PI4-kinase antagonist, reduced the amount of (125)I-NT-3 retrograde transport in sympathetic neurons by approximately 50% and (125)I-NT-4 in sympathetic neurons by approximately 40% and sensory neurons by approximately 20%. The PI3-kinase antagonist LY294002 (100 nmol/eye) reduced the retrograde axonal transport of (125)I-NT-4 in sympathetic and sensory neurons, and (125)I-NT-3 in sympathetic neurons. Phenylarsine oxide (PAO), a PI4-kinase antagonist, significantly inhibited (125)I-NT-4 retrograde axonal transport in sympathetic and sensory neurons. These results show that wortmannin-sensitive PI3-kinases and PI4-kinases may be involved in NT-3 and NT-4 retrograde axonal transport. The retrograde axonal transport of neurotrophic factors in sympathetic and sensory neurons in vivo appears to depend upon the activation of different receptors and second messenger cascades at the nerve terminal.  相似文献   
47.
Hypertolerance to morphine in G(z alpha)-deficient mice   总被引:2,自引:0,他引:2  
Our laboratory has generated a mouse deficient in the alpha (alpha) subunit of the G protein, G(z), (G(z alpha)) gene and we have examined the involvement of G(z alpha) in spinal and supraspinal analgesia and tolerance mechanisms. Spinal analgesia was tested by the response times to heat or cold tail flick times in a water bath at 50 degrees C or -5 degrees C and supraspinal analgesia was tested by the times for paw licking and jumping from a plate at 52 degrees C or 0.5 degrees C. Tolerance to morphine was induced in wild type and G(z alpha)-deficient mice over a 5 day period and the behavioral tests were performed daily. The tail flick reaction times to both hot and cold stimuli did not differ between the wild type and G(z alpha)-deficient mice. Analysis of the reaction times from the hot and cold plate tests showed the G(z alpha)-deficient mice developed tolerance to morphine to a greater degree and at a faster rate than wild type mice. Opioid binding assays were performed on synaptic membranes prepared from naive and morphine tolerant wild type and G(z alpha)-deficient brains. No changes in the affinity of morphine for its receptor or in the density of mu and delta opioid receptors were found between the two groups of mice in the naive or morphine tolerant state. This indicates that the absence of G(z alpha) does not affect opioid receptor affinity or receptor up or down regulation. Our results suggest that the presence of G(z alpha) delays the development of morphine tolerance and represents a possible therapeutic target for improving the clinical use of morphine.  相似文献   
48.
OBJECTIVE: To assess the impact on patterns of recurrence of adjuvant chemotherapy in patients with stage 1 nonseminomatous germ cell tumours (NSGCT) of the testis, who have a high likelihood of relapse on surveillance if certain risk factors are identified in the orchidectomy specimen, and thus the theoretical need for retroperitoneal lymph node dissection (RPLND). PATIENTS AND METHODS: The incidence of abdominal relapse was recorded in 417 men presenting with stage 1 NSGCT over the past 18 years. Up to 1986, 161 men were managed by surveillance alone, and abdominal relapse occurred in 26. From 1986 onwards, men with positive risk factors in the orchidectomy specimen were offered two courses of chemotherapy; 60 accepted and one relapsed in the abdomen, and 196 underwent surveillance and 19 relapsed in the abdomen. RESULTS: Abdominal relapse was significantly reduced from 16% before 1986 to 8% afterward (P = 0.014). Mortality from testicular tumour or treatment toxicity remained low, at 0.6% before 1986 and 2.0% since then. CONCLUSION: The need for RPLND in stage 1 NSGCT remains highly doubtful.  相似文献   
49.
50.
Plasma samples obtained from 97 children enrolled in a longitudinal study of HIV-1 perinatal transmission in S?o Paulo, Brazil, were tested for the presence of specific V3-loop antibodies in order to determine the HIV-1 subtype circulating among them. A set of seven synthetic peptides representative of the predominant HIV-1 subtypes detected in Brazil was employed in an in-house enzyme immunoassay (EIA) using two different protocols, one of which permits identification of high avidity antibodies (HAAb). Using these approaches we were able to detect antibodies in 64 out of 97 children, independently of the HIV-1 infection status, indicating the presence of subtype B in all cases, except one, which could be considered to be of subtype F. Among subtype B cases, half of the samples reacted with the GWGR motif (type W is representative of Brazilian B strains). In the main, concordant results were obtained between peptide-EIA and HIV-1 status among infants, although in several cases of truly HIV-1 infected children, negative results could be observed. Thirteen mother-child pairs and four fathers were also evaluated, and the results confirmed subtype B to be the prevalent one among them, showing similar proportions of P and W types. Taken together, the results obtained identified subtype B (W and P) uniformly among adults and HIV-1 infected children from S?o Paulo, Brazil, and confirm vertical and sexual transmission of the predominant strains.  相似文献   
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