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1.
In 1985, the Pan American Health Organization adopted the goal of eradication of poliomyelitis from the Americas by 1990. Strategies to accomplish this included high vaccination coverage, aggressive outbreak control, and active surveillance for acute flaccid paralysis (AFP). Although the sensitivity of AFP surveillance for detecting paralytic poliomyelitis cases is high, studies have shown the specificity to be low. In 1990, 2497 notified cases of AFP were investigated in the Americas of which 2146 had stool specimens collected. However, only 18 were confirmed as poliomyelitis by isolation of wild poliovirus from stool specimens, 71 were classified as being compatible with poliomyelitis. Cases of AFP due to causes other than poliomyelitis result in extensive but unnecessary outbreak control measures. To predict, at initial clinical evaluation, the likelihood of future confirmation as a case of poliomyelitis, likelihood ratios (LR) were calculated for different combinations of clinical characteristics of AFP cases (249) from Mexico in 1989 and 1990. The best predictors in a child with AFP were proximal muscle involvement which progressed '4 days together with fever at onset of paralysis, and proximal and unilateral involvement with either fever at onset or paralysis which progressed '4 days. The odds would increase by 12 that the child would eventually be confirmed as poliomyelitis (19), based on a stool culture positive for wild poliovirus (95% confidence interval (CI) 2.6-55.9). A guide for use in the field is proposed whereby local health officials, often with little training in neurological evaluation, can predict at initial clinical examination the likelihood that an AFP case will subsequently be confirmed as poliomyelitis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Regulations controlling the manufacture and use of carcinogens in the industrial setting of various countries are examined. In addition, the occupational exposure limits (OEL) of chemicals known or suspected to be carcinogenic in humans are listed, and criteria for the establishment of OELs are discussed. It is also stressed that control measures should not be confined to a few developed countries, and it is hoped that attracting attention to their unevenness will contribute to the implementation of a more efficient primary prevention of cancer.  相似文献   
3.
The intercellular distribution of O6-methylguanine-DNA methyltransferase (MGMT) mRNA expression has been investigated at the individual cell level in the liver of rats treated with dimethylnitrosamine using in situ hybridization. Male BDIV rats were orally administered with a single dose of dimethylnitrosamine (5 or 10 mg/kg) and were killed at 24, 48, and 96 hours after exposure. Constitutive MGMT mRNA expression was found in bile duct cells, vascular endothelial cells, and fibrous cells; however, weak or negative expression was detected in hepatocytes and Kupffer cells. On the other hand, after exposure to dimethylnitrosamine, inducible MGMT mRNA was rapidly expressed in hepatocytes, especially in the centrilobular area at earlier time points, confirming our previous studies in which enzymatic activity has been measured in different purified cell populations obtained by differential centrifugation. Immunohistochemical detection of the O6-methylguanine-DNA adduct formation was demonstrated in a dose-dependent fashion and was mainly found in the centrilobular hepatocytes where high levels of MGMT mRNA were present. These results suggest a correlation between the induction of this repair activity and DNA damage; however, the relationship between MGMT mRNA and enzyme activity remains to be fully established for all cell types.  相似文献   
4.
5.
Distinct species differences exist between BDIV rats and Syrian Golden hamsters in the repair of methylated DNA lesions, after single exposures to dimethylnitrosamine (DMN). The promutagenic lesions O6-methylguanine (O6-MeG) and O4-methylthymidine were actively repaired in rat liver; in contrast, in hamster liver the levels of O6-MeG remained relatively stable while O4-methylthymidine levels were reduced. Species differences in the levels of two enzymes involved in the repair of DNA alkylation damage were also noted. An increase in the methylpurine-DNA glycosylase levels was seen in both species following DMN exposure; however, significant species differences in the inactivation and subsequent time course of recovery of the "suicide protein" O6-MeG-DNA methyltransferase were observed. In the rat a rapid recovery of activity began within 24 h of DMN exposure (20 mg/kg) and an approximately 3-fold induction in enzyme levels was observed at 96 h. In hamster liver, in which the constitutive level of expression of this enzyme is similar, no activity was detectable up to 96 h after treatment (25 mg/kg DMN). Only in animals in the lowest treatment group (2.5 mg/kg DMN) was a significant recovery seen, 264 h after treatment. The data presented suggest that the schedule of DMN treatment, in particular the time between doses of the carcinogen and the regeneration of the O6-MeG-DNA methyltransferase, would evoke different carcinogenic responses in hamster and rat liver following chronic exposure to alkylating agents.  相似文献   
6.
This article outlines a new supervision practice of narrative therapy-informed reflecting team-based relational interviewing for a high-conflict stuck case of a separated middle-aged couple. The article demonstrates the supervision method consisting in five parts. First, the supervisor interviews the couples' relationship while the team watches from behind the one-way mirror. Second, the team responds to the interview while the couple and the supervisor witness their conversation. The couple is then invited to respond back to the team. Furthermore, there is a meta-conversation about the supervision in collaboration with the couple. The intervention ends with therapeutic letter writing to the relationship. The couple showed a meaningful shift in their positioning towards a more relational awareness and found valuable ways for continuing their therapy. The theoretical elements of the approach underpinning practice to tackle high conflict are considered through the illustration of the case.  相似文献   
7.
The incidence of second primary lung cancer (SPLC) seems to have increased in recent years. In our series that included more than 4000 patients with lung cancer and 1600 operations, we observed 26 cases of SPLC up until June 1999. We considered the standard criteria accepted by most authors for the selection. Characteristics of patients and tumors at the time of the first operation were compared with the statistical data of our general series. Age, sex, performance status and smoking were all considered, as well as cancer site, histology, stage and type of first surgical operation. No significant independent factor could be identified for the prediction of a new tumor at that time. A second operation was possible in 16 cases: two patients died in the postoperative period, two survived for 12 and 24 months, respectively, 12 are still alive 8-87 months after the new resection. The high rate of surgical cases (16/26 = 62%) and a good survival rate is clearly correlated with an early diagnosis of SPLC.  相似文献   
8.
BACKGROUND: The surgical treatment of large wall defects conventionally defined as an extension over 10 cm is discussed. The difficulty to contain the bowels that have lost law of domicile in the abdominal hollow, constitutes motive for notable increase of the endo-abdominal Pressure with serious consequences in the postoperative course and this leads to the use of prothesis meshes that allow the closing of the abdominal hollow with the Tension-Free technique. METHODS: Personal experience embraces 45 patients, with large wall defects, divided into 21 patients with overumbilical location, 14 with umbilical location, 10 with periumbelical location; a simple suture has been used in 7 cases, the reconstruction of the wall according to Stoppa in 36 cases and the apposition of Goretex net internally and Marlex net externally in 2 cases. RESULTS: There have been neither mortality, neither recidivists of illness, but only some complications: 9 cases of superficial infection, 1 case of intestinal occlusion and 2 of subcutaneous seroma. CONCLUSIONS: According to their experience and wide literature review, the authors draw some conclusions: an accurate toilet and a careful evaluation of the respiratory functionality are fundamental; it's necessary to postpone surgical intervention in presence of local inflammation and, where this is improrogable it's opportune to avoid the use of prothesis meshes or refold on readsorbible prothesis; special care must be taken to the hemostasis and an aspirative drain for 24-48 hrs preserves from the risk of postoperative hematomas and following local infections. The submuscular mesh permits a Tension-Free suture and for this reason it would have nowdays a more extensive use. Finally it's pointed out the choice of a PTFEe mesh in contact with the intestinal skein.  相似文献   
9.
Over the past 30 years, there has been considerable controversy regarding the role of segmental and wedge resections in the management of stage I (T1-T2N0M0) non-small-cell lung cancer. Recently, a prospective randomized trial (Lung Cancer Study Group, 1995) revealed unfavorable results after limited resection, which, in early stage lung cancer, remains a reasonable option for patients with compromised pulmonary reserve, especially those in whom a previous contralateral resection has been performed. The following report describes the role of limited resection in the management of patients with T1-T2N0 non-small-cell lung cancer and presents a retrospective review of our series of 125 limited resections out of 1356 resections performed for lung cancer. In particular, long term survival and the frequency of local/regional recurrence were noted in 92 cases operated on with a curative intent. 26.6% vs 12.5% local/regional recurrence rates were observed among patients undergoing limited resections for T2 and T1 lung cancer, respectively. The five year survival in the limited resection group was 13.5% for T1 and 60% for T2 vs 51% and 72% in the standard procedure group, respectively. The lobectomy results were superior to those of sublobar resection. The latter should be reserved for patients in poor general condition contraindicating a standard lobectomy.  相似文献   
10.
High rates of hepatocellular carcinoma (HCC) in The Gambia, West Africa, are primarily due to a high prevalence of chronic hepatitis B virus infection and heavy aflatoxin exposure via groundnut consumption. We investigated genetic polymorphisms in carcinogen-metabolizing (GSTM1, GSTT1, HYL1*2) and DNA repair (XRCC1) enzymes in a hospital-based case-control study. Incident HCC cases (n = 216) were compared with frequency-matched controls (n = 408) with no clinically apparent liver disease. Although the prevalence of variant genotypes was generally low, in multivariable analysis (adjusting for demographic factors, hepatitis B virus, hepatitis C virus, and TP53 status), the GSTM1-null genotype [odds ratio (OR), 2.45; 95% confidence interval (95% CI), 1.21-4.95] and the heterozygote XRCC1-399 AG genotype (OR, 3.18; 95% CI, 1.35-7.51) were significantly associated with HCC. A weak association of the HYL1*2 polymorphism with HCC was observed but did not reach statistical significance. GSTT1 was not associated with HCC. The risk for HCC with null GSTM1 was most prominent among those with the highest groundnut consumption (OR, 4.67; 95% CI, 1.45-15.1) and was not evident among those with less than the mean groundnut intake (OR, 0.64; 95% CI, 0.20-2.02). Among participants who had all three suspected aflatoxin-related high-risk genotypes [GSTM1 null, HLY1*2 (HY/HH), and XRCC1 (AG/GG)], a significant 15-fold increased risk of HCC was observed albeit with imprecise estimates (OR, 14.7; 95% CI, 1.27-169). Our findings suggest that genetic modulation of carcinogen metabolism and DNA repair can alter susceptibility to HCC and that these effects may be modified by environmental factors.  相似文献   
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